Companion Quarterly Vol28 No1 March 2017 by Companion Quarterly

COMPANION QUARTERLY â&#x20AC;&#x201C; Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA

Companion Quarterly

OFFICIAL NEWSLETTER OF THE COMPANION ANIMAL VETERINARIANS BRANCH OF THE NZVA Volume 28, No. 1 | March 2017

VOLUME 28 NO 1 MARCH 2017

Managing ureteral obstruction

Malocclusions

Guidelines for managing feline hyperthyroidism

Recurrent coxofemoral joint luxation

Challenges and pitfalls of diabetes mellitus

Volume 28 | No. 1 | March 2017 ISSN No. 2463-753X EXECUTIVE COMMITTEE 2017 cas@vets.org.nz

CONTENTS

President

Helen Beattie

Companion Quarterly

Operations Manager Rochelle Ferguson

Treasurer

Aimee Brooker

Committee Members Simon Clark Nina Field John Munday Toni Anns Natalie Lloyd Pauline Calvert

EDITORAL COMMITTEE Sarah Fowler (Editor) Bart Karalus Crystal Loh Ian Millward Juliet Matthews Simon Clark Shanaka Sarathchandra

Address for submitting copy/ correspondence

Sarah Fowler 66 Callum Brae Drive, Rototuna, Hamilton 3210 T (H) 07 845 7455 | M 027 358 4674 E sarah.fowler@gmail.com

Advertising Manager

Christine Moloney 25 Manchester St, Feilding T 06 323 6161 | F 06 323 6179 E christine.moloney@totallyvets.co.nz

NZVA website www.nzva.org.nz CAV website www.cas.nzva.org.nz Copyright

The whole of the content of the Companion Quarterly is copyright, The Companion Animal Veterinarians Branch of the NZVA (CAV) and The New Zealand Veterinary Association (NZVA) Inc.

Cover photograph

Courtesy of Genevieve Rogerson and shows Maddie the Burmese looking very smug after stealing her canine sister's new comfy bed.

Newsletter design and setting Penny May T 021-255-1140 E penfriend1163@gmail.com

Disclaimer The Companion Quarterly is a non peer reviewed publication. It is published by the Companion Animal Veterinarians Branch of the NZVA (CAV), a branch of the New Zealand Veterinary Association Incorporated (NZVA). The views expressed in the articles and letters do not necessarily represent those of the editorial committee of the Companion Quarterly, the CAV executive, the NZVA, and neither CAV nor the editor endorses any products or services advertised. CAV is not the source of the information reproduced in this publication and has not independently verified the truth of the information. It does not accept legal responsibility for the truth or accuracy of the information contained herein. Neither CAV nor the editor accepts any liability whatsoever for the contents of this publication or for any consequences that may result from the use of any information contained herein or advice given herein. The provision is intended to exclude CAV, NZVA, the editor and the staff from all liability whatsoever, including liability for negligence in the publication or reproduction of the materials set out herein.

2 Editorial 4 Highlights from CAS Executive Meeting

6 CAV Noticeboard 14 Managing canine and feline ureteral obstructions Alastair Coomer

18 Malocclusions

Angus Fechney

22 The Nobel Prize-winning G-man is dead

24 Feline hyperthyroidism –

guidelines for management and other information Boyd Jones

32 How I manage recurrent

luxation of the coxofemoral joint Andrew Worth

38 Challenges and pitfalls of

managing diabetes mellitus Dr Pru Galloway

40 Conference report: Valentine Charlton Feline Medicine Conference Orla Fitzpatrick

43 Conference report: Highlights from the 8th World Congress of Veterinary Dermatology Duncan Graham

47 Conference report: 41

st World Small Animal Veterinary Congress Mike Scully

49 Massey News 50 New Zealand Companion Animal Council Update

51 2016 Subject Index

Vets in Stress Programme 24 Hour Freephone Confidential Counselling Service

0508 664 981 Helps you solve personal and work problems, including: Relationship problems Drug and alcohol issues Work issues Change Stress Grief

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

EDITORIAL

2016 was quite a year……. I have to pinch myself from time to time – what’s going on in the world makes me doubt that a) I’m awake, and b) it can be 2017. It was quite a year – for me, for our industry, and for the world, in general. Recently I went to see comedian Jim Jefferies live; there was a sweepstake on how many sentences/minutes would pass, before Trump got a mention. It took Jim about four minutes to get around to it, and strangely here is my fourth sentence! While neither candidate for the US presidency looked particularly appealing to me, I am nevertheless left completely bewildered how such a man, who has openly admitted to so many heinous doings, has been elected to lead one of the world’s superpowers. I’m not well-educated enough to wade in on US politics – but I do feel reasonably well positioned to comment on his sexist and misogynistic comments and actions. It is nothing short of outrageous that despite this, he has been elected to lead the USA. I wonder when, if ever, we are going to see the end of this sort of inequality, where the behaviours that he speaks of, and admits to having committed, are in some way deemed acceptable, or at least that they should not preclude him from taking a position of supreme power. And I belong to but one subset of those that have been defiled. Lost for words…. It’s been quite a year for the world – and this is but one (small?) example. So given this, were we even more highly alert and on guard for such positioning and behaviour, and even less tolerant, given the context within which the world finds itself? Probably rightly so – for I find Trump rattles the very core of what we expect from decent people, in a developed world.

Enter Chris Kelly and some very poorly thought out comments made to the media about our industry. The female veterinary “issue” has raised its head before in my life, not long after I started at veterinary school – I stamped my US size 9 (men’s) feet, and shrieked about the injustice. I thought I had made a difference. Yet nearly 20 years down the track, the very same conversation is occurring, which defies belief, is illogical, and just plain untrue. One can only hope that the outrage about such injustice and inequality is now so widespread, that this, in fact, indicates that our positioning and thoughts, or at least those of the majority, have indeed changed. This is not my own experience necessarily, and Christmas will be less conflict-full next year, if I learn to bite my tongue! It was quite a year for the veterinary industry - and this is but one (small?) example. Never one to shy away from an argument or a challenge, I have also been personally challenged by taking on a new role as an Animal Welfare Inspector for the SPCA indeed the Chief Inspector, managing the Otago inspectorate. The role is challenging. The scenarios can be challenging. The people with whom I have to deal are challenging. Tough decisions have to be made. All of them have to be inside the law (unless you choose to “step off. And then you need to know you have stepped off.” Alan Wilson, pers. comm., 2016). The law can be so limiting – sometimes you just know what is right or wrong, but the law is the law.

explaining to my friends that actually, no, it’s not OK to just drown your unwanted puppies, stitch up your dog, dock your dog’s tail, have skinny pig dogs, or to castrate your own cat. And trying to do this without being seen as an annoying activist and bunny hugger, with radical views. That I am not – but doing this work has radically changed my views on many things, as I am educated and challenged in my thinking. We all wear welfare hats – it’s part of our job as a veterinarian. The challenge, I find, is separating common practise, from the offence, and wilful offending. How do we educate the public to think differently about these issues? Where are our opportunities as veterinarians to contribute to changing thought processes? How does this contribute to our profession and the value that we provide to our clients, and animals? How do we use this knowledge to make us indispensable, in a world with increasing pressures on income and discretionary cash? It’s an evolving journey – life – including realignment and development of more sophisticated, and well-informed positions. Unless you are Trump – then you can still behave like you live in the 1950s. It was quite a year for me – veterinarian, animal welfare inspector – and this is but one (small?) example. Helen Beattie, CAV President. l

But perhaps most challenging is wearing the SPCA hat – not my veterinary hat, not my education hat, and not my high country farmer’s daughter’s hat – but my SPCA hat, and dealing with and

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

WORKING TO PROMOTE AND SUPPORT COMPANION ANIMAL PRACTICE IN NEW ZEALAND

Highlights from the CAV Executive Committee meeting November 2016, by teleconference

Feline renal transplanation policy

This policy is due for review and after consultation with surgical and medical specialists, the committee have altered the NZVA position from being one where this procedure was conditionally supported, to one in which this procedure is not supported. The reasons for withdrawing support are the lack of clear benefits over comprehensive medical management, the ethical dilemmas associated with sourcing a donor kidney and poor access in New Zealand to the team of specialists who can provide the level of expertise needed to support the recipient at all times and ensure their ongoing welfare.

MRSP surveillance

Allan Bell has raised concerns on the lack of surveillance of this organism to allow early notification if imported types are present in New Zealand. The committee will initiate discussions with the laboratories with the view to establishing an informal register that can be used to provide early warning of cases that may be imported into New Zealand.

New Zealand Kennel Club (NZKC)

The NZKC Health and Welfare Committee have invited CAV to be represented on this committee. Cath Watson has agreed to join on behalf of CAV.

The committee also expressed concerns about the legitimacy of advice given by Sarndra Urwin (a holistic natural therapist) on health conditions. It was decided to put these concerns in writing to the DogWorld Editor. CAV had already sent a letter to ACVM earlier this year voicing concerns about the claims that Sarndra Urwin was making regarding homeopathic vaccinations.

Fireworks

Whilst the NZVA supported a ban on fireworks in 2016, it was noted that the fire service had moved to a position of educating the public on how to use them safely, rather than supporting a ban. It was thought that CAV efforts may be better directed at focusing on how to manage pets around fireworks rather than working towards a total ban, in line with the fire service position.

Cath Watson

After serving the committee for 8 years, 5 of them in the role of President, Cath Watson announced that she would resign at the end of 2016. The committee will miss having Cath at the table and thanked her for the amazing contribution she has made to CAV, particularly as the President during the time that CAV was hosting WSAVA in 2013. l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

The CAV Noticeboard Hill’s Pet Nutrition/CAV Educating the Educators Scholarship This scholarship provides assistance for veterinary educators to attend advanced level continuing education events outside New Zealand, in exchange for articles, reports and presentations on their area of interest. Through this partnership, we recognise the importance in supporting our leading veterinarians’ participation in international conferences to ensure they remain up to date, and disseminate this knowledge to the wider CAV membership. This scholarship is open to both CAV members and non-members. Successful applicants are usually specialists in their field but we also support those who have developed advanced skills in a specialist area.

If you would like to partner with us to improve the knowledge of NZ veterinarians, then see our website, or contact cav@vets.org.nz for application forms and a list of the terms and conditions. Applications are usually considered at the end of March and September each year. We have $10,000 per annum to grant and are very keen to have this resource utilised to support and promote companion animal veterinarians. We are very grateful to Hill’s Pet Nutrition as the principle sponsor along with support we receive from the Institute of Veterinary, Animal and Biomedical Sciences and VetLearn.

Hill’s Pet Nutrition/CAV Educating the Educators Scholarship: an update The article titled 'The proaactive management of canine atopic disease' by Duncan Graham on page 28 of the September issue of Companion Quarterly (volume 27 no 3) 2016 has retroactively been accepted as fulfilling part of the requirement of receiving the Hill's Pet Nutrition/CAV Educating the Educators Scholarship.

G SCH RAN OL TS & AR SH Ava IPS ilab CAV le to me mb ers

CAV/CAHF Project Grant 2017 The Companion Animal Health Foundation is a charitable trust that acts as the research funding arm for CAV. Funding applications from CAV members are invited in March and September for research projects that will enhance companion animal health and welfare.

See the CAHF website (www.healthypets.org.nz) to find out how we are supporting projects on elbow dysplasia, bone marrow sampling techniques and FIV prevalence. Any queries on how to make an application or donate contact Rochelle Ferguson (CAV Operations Manager) on cav@vets.org.nz

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

The CAV Noticeboard

WINNER

Article of the Issue

Zoe Kamsma

“The use of pimobendan for the treatment of hypertrophic cardiomyopathy in a cat” June 2016 | Volume 27 (4) | Pages 32–36

EYEVET Services Limited

WINNER

Article of 2016

Philomena Tuohy

“Diskospondylitis – A case-based review” March 2016 | Volume 27 (1) | Pages 26–30

EYEVET Services Limited

WINNER

Undergrad Student Article of 2016

Zoe Kamsma

“The use of pimobendan for the treatment of hypertrophic cardiomyopathy in a cat” June 2016 | Volume 27 (4) | Pages 32–36

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

INDUSTRY NEWS

Ears in Pain When treating otitis externa in cats and dogs, a quick and effective cure is more likely if the outer ear canal is cleared of wax, discharge and debris before administering topical antimicrobial and anti-inflammatory medication. A clear ear canal makes it easier to perform an otoscopic examination and removes barriers allowing treatment to access the target organisms. Epi-Otic® solution softens skin, softens earwax, removes scale and crust, pus, sebum, discharge, foreign debris and dead cells, and flushes them from the ear canal. Used ½–1 hour before treatment for otitis externa, Epi-Otic® dries the ear canal and doesn’t dilute subsequent medication. Epi-Otic® solution contains lactic acid and salicylic acid to soften keratin so antimicrobials can penetrate. They work with propylene glycol which stops bacteria reproducing, removes wax, and is hygroscopic. Sodium docusate helps remove ear wax and is also a drying and spreading agent. It creates a hostile environment to bacteria and yeast and prevents them from adhering to epithelial cells. Epi-Otic® also contains the broad spectrum antimicrobial chloroxylenol which targets common pathogens found in the external ear canal. Because the formula doesn’t contain alcohol, it doesn’t irritate the animal. Warmed solutioni, which is more comfortable for the patient, should be applied liberally to the entrance of the ear canal and the ear gently massaged to disperse the product throughout. Any excess Epi-Otic® and dirt which has been dislodged into the outer ear can be wiped away. The process should be repeated until the ear is flushed clean. Once the ear canal is clear, easOtic® is the ideal solution for treating otitis externa in dogs. There is nothing else like easOtic®. easOtic® contains the aminoglycoside antibiotic gentamicin sulphate, the imidazole antifungal miconazole nitrate and the anti-inflammatory glucocorticoid diester hydrocortisone aceponate. These are effective against major ear pathogens commonly associated with otitis externa in dogs including Staphylococcus intermedius, Pseudomonas aeruginosa, Proteus spp. and Malassezia pachydermatisii. easOtic® is formulated to adhere to the ear canal, allowing it to persistently target microbes. It comes in an easy-to-use airless pump dispenser with a soft nozzle to prevent trauma to dogs’ ears. The dispenser can operate from any angle which helps when medicating dogs that back into corners or roll onto their backs, making medicating easier for non-expertsiii. Ear canals in dogs are a fairly consistent size across all breedsiv. One pump of the dispenser delivers the exact 1 ml daily dose suitable for most dogs. Treatment is for 5 consecutive days, and antimicrobial activity persists 7–10 days after the course of treatment is finishedv. After treatment is completed, Epi-Otic® can be used regularly to maintain clean, dry ears, and help prevent recurrence of otitis externa, especially for dogs that swim, have narrow ear canals, or a history of ear disease. Predisposition to ear disease is very likely to be due to atopy. Inhaled allergens, usually pollens, can cause inflammation anywhere in the body, but the moist dark folds of skin in the ear seem particularly prone. Swelling narrows the canal. Inflamed canals produce excessive wax and debris. Dilated blood vessels make the ear into a warm incubator. Treating a dog’s infection will cure it this time, but recognising and managing the predisposition will help prevent infections and further damage in the future. It is easiest to warm Epi-Otic® by standing it in a jug of warm tap water for 10 minutes. Rigaut D, Sanquer A, Maynard L, Reme C. Efficacy of a topical ear formulation with a pump delivery system for the treatment of infectious otitis externa in dogs: a randomized controlled trial. The International Journal of Applied Research in Veterinary Medicine 9, 15–28, 2011 iii Boda C, Liege P, Reme C. Evaluation of owner compliance with topical treatment of acute otitis externa in dogs: a comparative study of two auricular formulations. The International Journal of Applied Research in Veterinary Medicine 9, 157–65, 2011 iv Forsythe WB. Tympanographic volume measurements of the canine ear. Americal Journal of Veterinary Research 46, 1351–3, 1985 v Budgen DL. Identification and antibiotic susceptibility of bacterial isolates from dogs with otitis externa in Australia. Australian Veterinary Journal 91, 43–6, 2013 i

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

INDUSTRY NEWS

Bravecto® – approved new claims

MSD Animal Health are pleased to announce exciting new claims for the Bravecto® range:

- Treatment and control of Otodectes cynotis and Sarcoptes scabiei var canis mite species in dogs. - Highly effective against fipronil resistant fleas in cats and dogs. - Sustained control of new flea and tick infestations for 3 months in cats and dogs* Bravecto has become a popular and effective licensed treatment for demodicosis, and part of treatment strategies for the control of Flea Allergy Dermatitis (FAD). Its efficacy for treatment and control of Otodectes and Sarcoptes mites will extend its usefulness, all in one easy to give chewable tablet, with 3 full months efficacy. This will make it even easier for clients to remember when their next dose is due, and may fit in well with your recommended worming regimes. To make it easy to remember when to retreat there is a new Bravecto reminder app available for Apple and Android devices. Here we report data from the Sarcoptes study to support these claims. Please refer to MSD Ectoparasiticide Technical Bulletin (2016) for data to support the Otodectes claim, or Companion Quarterly for an Otodectes case study by Dr. Hannah Bain.1

Efficacy of Bravecto against sarcoptic mange in dogs:2

A parallel group, randomised, controlled study involving 29 mixed breed dogs with naturally acquired Sarcoptes scabiei var. canis infestations and mites found on skin scraping was conducted. Results Treatment Assessment time-point Pre-treatment Mean mite counts Count range 4 weeks post-treatment Mean mite counts Count range Efficacy

Saline (n=9)

Bravecto chewable tablet (n=9)

10.6 2–34

12.0 2–163

7.9 1–55 n/a

0 0 100%

Table 1: Geometric mean mite counts and efficacy (%) in dogs with sarcoptic mange after a single oral or topical treatment with Bravecto (fluralaner).

Bravecto spot-on for cats

Bravecto spot-on for cats is changing the game this summer in the fight against fleas and ticks. Three months of effective treatment and control against fleas and ticks in one easy spot-on dose. Bravecto spot-on for cats can be a very useful part of a treatment strategy for the control of FAD and is highly effective against fipronil resistant fleas. A multi-centre field study of 224 client-owned cats from 116 households included cats with clinical signs attributed to FAD3. Of the cats showing signs of FAD, at least 80% of cats treated with Bravecto spot-on for cats had resolution of all signs attributed to FAD at week 12, with no other treatment administered that could affect assessment of FAD.3 For further information regarding these new approved label claims please contact MSD on 0800 800 543 or your local MSD sales representative. * previously 12 weeks in dogs.

Bain H, Hasselman H. Efficacy of Bravecto against earmites in 16 hound puppies. Companion Quarterly 27(3), 36–8, 2016 Taenzler, Liebenberg et al. Efficacy of fluralaner administered either orally or topically for the treatment of naturally acquired Sarcoptes scabiei var. canis infestation in dogs. Parasites & Vectors 9, 392, 2016 3 Meadows, Guerino and Sun. A randomized, blinded, controlled USA field study to assess the use of fluralaner topical solution in controlling feline flea infestations. Parasites & Vectors 10, 37, 2017

Bravecto ACVM No. A11019 and A11261. ®Registered trademark. Schering-Plough Animal Health Ltd. Ph: 0800 800 543. www.msd-animal-health.co.nz. NZ/BRV/0117/0001

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

FEATURE ARTICLE

Managing canine and feline ureteral obstructions This article was written as part of the requirements of receiving the Hill’s Pet Nutrition/CAV Educating the Educators Scholarship

ALASTAIR COOMER

BVSc, MS, Dipl. ACVS, Registered Specialist – Small Animal Surgery, Veterinary Specialists Auckland and Veterinary Specialist Group

Diagnosis of ureteral obstruction

The Merck Manual describes the symptoms of ureteral obstruction in humans to be pain that “…may radiate down the abdomen toward the groin…nausea and vomiting, restlessness, sweating, … an urge to urinate frequently…”. While these symptoms are relatively nonspecific, they are easily described by the patient. These same symptoms can be associated with ureteral obstructions in cats and dogs, but efficiently differentiating between the myriad of other potential causes can be challenging. Many of the cases we see also have intermittent symptoms, and while their symptoms are severe at home, they may seem outwardly normal during consultation. If symptoms are severe enough, or recurrent, then a ureteral obstruction will often become apparent during workup. One of the important aspects of ureteral workup, is that we shouldn’t abbreviate the workup or cut corners. Critical and complimentary information is obtained from full bloodwork, serial blood pressure measurement, abdominal radiography, abdominal ultrasound (or computed tomography), urinalysis and urine culture. The true incidence and prevalence of ureteral obstruction is unknown in New Zealand dogs and cats. I recently surveyed our staff at Veterinary Specialist Group and found that less that 25% of azotaemic animals in our practice have evidence of Contact: Alastair.Coomer@vsnz.co.nz, www.vsnz.co.nz

clinically relevant ureteral obstruction on abdominal ultrasound, and that most of the cases with ureteral obstruction were cats. In our practice more than 75% of azotaemic animals have an abdominal ultrasound, so this is probably an accurate representation of the incidence of ureteral obstruction in referral practice. Abdominal imaging is not necessarily indicated in every azotaemic animal, but if renal or post-renal azotaemia are on your problem list, then abdominal imaging will provide useful information. If both hydroureter to an obstructive lesion and renal pelvic dilation are identified on ultrasound, then ureteral obstruction is diagnosed. Often this diagnosis is not clear-cut, however. Renal pelvic dilitation is relatively obvious when the pelvis is dilated beyond 6–8 mm, but dilitation is technically present if the pelvis is dilated beyond 2 mm. The sensitivity of this assessment is very operator-dependent, but is fairly good at 77% for cats, and 100% for dogs. We always perform abdominal radiographs or CT in combination with ultrasound, as ureterolith location, size, number and shape are best identified with these imaging modalities. If no clear obstructive lesion is seen (but hydroureter and renal pelvic dilitation are present) then ureteral strictures, dried solidified blood stones or trigonal neoplasia are suspected.

Interestingly, ~17% of cats with ureteral obstructions will have a developmental anomaly called circumcaval ureter. In these cases, the right ureter wraps around the caudal vena cava and may become compressed by the vessel. These lesions are relatively easily identified by a proximal right sided ureteral obstruction on imaging, with no evidence of ureterolithiasis. “I have identified a ureteral obstruction, what next?”

Medical management

It is generally accepted that medical management of azotemia either works, or it doesn’t. In many cases of refractory azotaemia, it is assumed that renal injury or failure is to blame. Some of these cases may actually have ureteral obstruction and without identification and specific management of the ureteral obstruction, their symptoms and azotemia will likely persist. When deliberating how to manage ureteral obstructions, there are a few important facts to consider: • Return of normal renal function is not predicted by degree of obstruction or azotemia, but by duration of obstruction; urgent management is essential. • 95% of cats will experience renal recovery after the obstruction is relieved, regardless of azotemia. • Renal pelvis size does not predict the cause or outcome of obstruction. • Diuresis or pyelonephritis may cause renal pelvic dilitation but ureteral obstruction will also cause hydroureter. • Only 15% of cats will resolve with medical management and ony ~8% have documented stone passage. Basic medical management revolves around opioid analgesia, 24–48 hours of intravenous fluid therapy, diuresis with mannitol and possibly alpha blockade (prazosin) as a ureteral smooth muscle relaxant. Broad-spectrum antibiotics are indicated since 35% of cats, and 75% of dogs with ureteroliths have positive urinary cultures. Treatment is usually continued for 48 hours and if azotemia and/or obstruction have not resolved in this timeframe, then intervention is indicated. Importantly, if hyperkalaemia, severe discomfort and/or oliguria/anuria are present at any stage of assessment or treatment, medical management should be abandoned in favour of immediate interventional therapy.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Ureteral interventions

Ureteral interventions come in many flavours, and all have their pros and cons. Most of the risks and complications are related to clinician experience/training, and procedural evolution over the years. Personally, I trained at a Veterinary Teaching Hospital (VTH) with an active kidney transplant programme, so most of my experience is with ureteral surgery. Ureteral surgery is very labour intensive, and hospitalization times can be many days. Many North American VTHs and tertiary referral hospitals now have active interventional radiology programmes, and are therefore offering interventional ureteral procedures on an outpatient basis. The main categories for ureteral intervention are surgery, ureteral stenting (dogs) or ureteral bypass (dogs and cats).

Ureteral surgery Ureteral surgery includes a wide range of techniques, including ureterotomy or reimplantation, ureteronephrectomy and/ or renal transplantation. Complication rates are high, and are clinically very relevant: ~35% of cats and dogs will have immediate post-operative uroabdomen related to ureteral leakage, and ~20% of cats will die in hospital before discharge. A further 25% will survive to discharge, but will fail to recover renal function, and die within the first month. To complete this rather bleak outlook, of the surviving cats, almost half will reobstruct within 12 months. For these reasons, I consider ureteral surgery to be truly palliative in cats, and I include these statistics in my honest conversations with families ahead of surgery. The ureteral surgery story is a little brighter for dogs, in that ~95% dogs will be discharged from hospital alive. Approximately 40% of dogs will have persistent renal dysfunction, however,

with a similar percentage having persistent or recurrent urinary tract infections (UTI). Long term, almost 30% of dogs will succumb to their disease.

Ureteral stenting Ureteral stenting is a minimally invasive intervention, reported to treat ureterolithiasis, neoplastic obstruction and strictures in both cats and dogs. Initial reports of ureteral stenting was relatively positive in the short term, with <10% procedural complications and mortality. Unfortunately almost 30% of feline stents occluded within the first 12 months, and required replacement/stent exchange. For this reason, ureteral bypass is now favoured in cats (see later). Dog have a larger ureter than cats, and can therefore accept a larger diameter ureteral stent. This dramatically reduces the risk of re-obstruction to ~10%. Ureteral stenting is also associated with <2% procedural mortality, making it very safe and effective at relieving ureteral obstruction. With improving clinical experience and caseload, canine ureteral stenting is performed as an outpatient procedure in North American tertiaty hospitals. The major long-term complication is persistent or recurrent UTIs which require ongoing medical management.

Ureteral bypass Subcutaneous Ureteral Bypass (SUB) allows diversion of urine from the kidney, through a subcutaneous injection port, and into the urinary bladder (Figure 1). It has evolved from ureteral stenting, to allow flushing of the ureteral prostheses/catheters in the case of future obstruction. SUB requires surgery to place the device, but operative times are still much shorter than traditional ureteral surgical techniques. Perioperative mortality is low at ~5%, but device reobstruction (~15%) and UTI (~15%) are the most common long-term complications.

Both of these can be managed with flushing of the SUB under sedation, or surgical exchange of the device.

My clinical thought-process The ultimate goal and the end of intervention should be a large-bore patent tube connecting the renal pelvis and urinary bladder. This is achieved in different ways, in cats and dogs.

Cats

Because of my positive experience with ureteral reimplantation in cats, I still recommend neoureterocystostomy (reimplantation of the ureters into the bladder) for distal ureteral obstructions. In my mind, there is no prosthesis (stent or SUB) that will behave as well as a patent and normal ureter. Therefore, if no stricture is present proximal to the clinical obstruction, the remaining ureter will be dilated, relatively easy to suture and be functional. If obstruction is proximal or multisite, then I recommend ureteral bypass with a SUB device. Ureteral stents are fraught with complications in cats, and are therefore not utilized, and almost 50% of cats with multisite obstruction treated surgically will reobstruct and die within 12 months which does not inspire surgical intervention in those cases.

Dogs

Thankfully the canine ureter is relatively large, and therefore amenable to multiple interventional techniques. A majority of dogs (~60%) with ureteral obstruction will have infection of the ipsilateral kidney (pyoneophrosis), so I recommend urgent intervention in any dog with documented ureteral obstruction. Specifically what intervention is utilized is case-dependent, but I try to save the affected kidney if at all possible. Again, in my hands, ureterotomy and neoureterocystostomy are my go-to procedures as they relieve the obstruction, allow natural egress of pyonephrosis and do not leave an implant/prosthesis in place that could harbour infection. With increased experience and confidence in stenting, however, it is likely that we will move towards ureteral stenting in dogs as these procedures are minimally invasive and have post-operative infection rates comparable to surgery.

Conclusion

Photo courtesy of Drs Allyson Berent and Chick Weisse

Considering the clinical urgency of cases with ureteral obstruction, it is encouraging to know that there are multiple management options available to us. It is also important to remember ureteral obstruction as a differential diagnosis for azotaemia in dogs and cats. Ureteral obstruction is uncommon in New Zealand, but it is important to diagnose this aetiology early in the disease process. l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

FEATURE ARTICLE

Malocclusions

This article was written as part of the requirements of receiving the CAS/Hill’s Pet Nutrition Educating the Educators grant

ANGUS FECHNEY BVSc, Companion Animal Dental Service Dental malocclusions in companion animals are a common presentation in veterinary practice. Malocclusion is defined as any deviation from normal occlusion, which may be due to abnormal positioning of a tooth or teeth (dental malocclusion) or due to asymmetry or other deviation of bones which support dentition (skeletal malocclusion) (Roux and Howard 2010). The American Veterinary Dental College defines “malocclusion” as being present when a tooth or teeth are not able to fit comfortably when the mouth is closed. The critical determination is whether there is evidence of tissue damage or loss of ability to chew comfortably. In these cases, treatment is indicated (Anonymous 2016). Etiology of malocclusion includes genetics, nutrition, trauma, environmental factors, as well as the mechanical forces generated by dental interlock (Bellows 2004; Gawor 2013). Normal occlusion in dogs is identified by the following: the upper incisors should overlap just rostrally to the tips/cusps of the lower incisors. The lower canines should sit midway between the maxillary 3rd incisors and canines when the mouth is closed. The cusps of the mandibular premolars should be directed between the maxillary premolars in the interproximal space with the cusps of the maxillary 4th premolars lateral/buccal to the mandibular 1st molars (Ross 1986). In 1890, Dr Edward Angle postulated three classes of malocclusion based around the occlusal relationships of the 1st molars (Proffit 2007). These Contact: A.Fechney@massey.ac.nz, (027) 587 0005

Source: pixabay/com

classifications have been modified into the current veterinary classifications by the addition of two extra classes (Class 0 and 4). l Class 0: normal occlusion l Class I malocclusion (MAL/1) or

neutrocclusion: The mandible and maxilla are in the correct position but a tooth or teeth are out of alignment l Class II malocclusion (MAL/2) or distocclusion: The mandible is shorter than the maxilla l Class III malocclusion (MAL/3) or mesiocclusion: The maxilla is shorter than the mandible l Class IV malocclusion (MAL/4) or mesiodistocclusion (maxillarymandibular asymmetry): a special type of presentation where one side of the jaw may be in mesioclussion whereas the other side may be in distocclusion or either side may actually be in normal occlusion.

In attempting to further assess occlusion, an understanding of different skull types (dolichocephalic, mesaticephalic, or brachycephalic) is necessary along with consideration of what is considered normal (or acceptable) within different species and breeds. For example a typical shih tzu has a pronounced class III malocclusion according to dental and medical standards but due to the breed standard this is considered “normal” and is known as a class 0 normal type 3 malocclusion. Interestingly, perfect bilateral body symmetry is a largely theoretical concept that seldom exists in living animals (Wiggs and Lobprise 1997)

The orthodontic exam

This should always (where possible) be performed in a conscious patient initially. Although aggression, excessive fear and impatience can preclude an extensive conscious oral exam and bite evaluation, remember that the relationship

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between the maxilla and mandible is often not the same under anaesthesia due to loss of natural tension of the masticatory muscles (Tutt 2007). A thorough orthodontic exam (Gawor 2013) should evaluate: 1 Head type (brachycephalic, mesaticephalic, dolichocephalic) 2 The symmetry of the face and relationship of the maxilla to the mandible 3 Dentition 4 Normal dental interlock in incisor teeth 5 Relationship of the canine teeth 6 Interdigitation of the premolars 7 Relationship and position of the molar teeth 8 Mobility of the mandible in a lateral and rostro-caudal direction as well as evaluating function and symmetry of the temporomandibular joint

Managing cases of malocclusion

Appropriate options for managing cases of malocclusion often depend on signalment (age, breed etc.), the type of malocclusion and the severity of disease (Hale 2005). Options include the following: 1 Review (i.e. no therapy with a review at a revist) As used in practice with other disciplines, this can be a very useful tool since many conditions will self-correct with time â&#x20AC;&#x201C; obviously the best outcome. However, more options may be available for dealing with orthodontic cases the earlier the cases are presented for surgery e.g. lingual displacement (linguoversion) of mandibular canines in young dogs. If this option is elected the client must be fully informed of potential outcomes if a procedure is delayed. 2 Exodontics or extraction of the offending tooth/teeth This may be a viable and comparatively inexpensive option where the teeth to be removed are easy to remove with minimal trauma to the animal e.g. lateral maxillary incisor removal to facilitate passage of mandibular canines in a grade III malocclusion. If possible removal of the structurally important teeth should be avoided. Whilst reducing the trauma to the animal, preservation of these teeth maintains the integrity of the jaw and surrounding structures (e.g. retention of the tongue by the mandibular canines). 3 Endodontics Where mandibular canines impinge on structures (both hard and soft tissue) of the maxilla, coronal amputation of the tip of canine teeth and vital pulp therapy is a common treatment option in Class II and sometimes Class III and IV malocclusions. 4 Orthodontics: correction using appliances and/or composite extensions The goal of orthodontic procedures in companion animals is to provide pets with a healthy and functional occlusion. Although it has been suggested that veterinary orthodontics is for cosmetic reasons only, the reality is that with careful case selection and client education, veterinary orthodontics should provide a measurable medical benefit to the animal (Gawor 2013). Even if obvious mouth pathology is associated with one tooth or a certain area of the mouth, all dental treatments should be proceeded by a Comprehensive Oral Health Assessment (COHA). This is particualrly vital for an orthodontic case since Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

it then allows accurate diagnosis and management of specific malocclussions.

Deciduous malocclusions

During the period prior to eruption of the permanent dentition, positional discrepancies that are not considered standard for the breed may be noted. A thorough oral examination when a puppy or kitten is presented for its initial vaccination course should be an essential part of a complete clinical examination. Critically evaluating the position of the teeth along with discrepancies in jaw length can allow timely intervention that may prevent a chronic malocclusion once the permanent teeth have erupted (Niemiec 2010). Severe malocclusions at this age may be permanent. Since the mandible typically grows later than the maxilla, Class II cases tend to have a better prognosis for return to normal occlusion compared to a similar Grade III malocclusion. The deciduous teeth are often trapped by either another tooth or the soft tissue on the opposite arcade which may interfere with the normal genetic growth potential that allows self-correction of malocclusion. This is known as an adverse dental interlock (Wiggs and Lobprise 1997). Due to the shape and sharpness of the deciduous teeth, maloccluded teeth may cause trauma in the opposite arcade resulting in bleeding that may be apparent on clinical examination. It is important to educate the client that occlusal trauma is painful despite often a lack of functional clinical signs. Treatment usually involves expedient and careful extraction of the impinging deciduous teeth. Interceptive orthodontics (selective extraction of certain teeth) may be needed to remove the adverse dental interlock (Harvey 1993; Hale 2005). Although it is often best to perform selective deciduous extractions as early as 6â&#x20AC;&#x201C;8 weeks of age, care is needed with the extraction of these teeth not only because of the fragility of the primary teeth but also as any excessive trauma or incomplete root tip extraction may induce enamel hypoplasia or enamel defects in the erupting permanent teeth. This may necessitate further restoration work at an older age due to exposure of the sensitive dentinal tubules in the damaged tooth. Pre and post-operative radiographs often provide critical information for planning and assessing this extraction process.

Class I malocclusions

Malocclusions associated with jaw length discrepancies (Class II, III and IV) are typically considered genetic in origin (Harris and Johnson 1991). In contrast, Class I malocclusions are generally considered non-genetic with the exception of some breed predilections e.g. mesioversed canines (lance effect) where the maxillary canines are tipped forward in Shetland Sheepdogs and Persian cats or base narrow mandibular canines in standard poodles (Shipp and Fahrenkrug 1992). Class I malocclusions, outside those of genetic origin or due to acute trauma, may result from pressure from oral structures (e.g. tongue, lip or cheek). They may also be secondary to significant systemic, endocrine, cystic or neoplastic issues (Wiggs 1997). Previously persistent deciduous teeth were implicated as a cause of Class I malocclusions. However human studies have shown that retention of these deciduous teeth is caused by improper eruption of the permanent teeth (Harvey and Emily 1993). If trauma or periodontal disease is already present or is likely to ensue, therapy to correct a Class I malocclusion is strongly advised as both of these conditions result in pain and possible premature loss of multiple teeth. For example, a fully erupted mandibular canine whose crown tip (or cusp) impinges on the hard palate may cause significant periodontal disease around the opposing maxillary canine or, at worst, result in an oronasal fistula. Similarly if overcrowding is present then this may increase the chances of advanced periodontal disease. Treatment options for Class I malocclusions include extraction, reduction in the crown length of a tooth with appropriate capping of the tooth (+/- vital pulpotomy) or orthodontic intervention e.g. base-narrow mandibular canine(s) causing trauma to the hard palate.

Class II and III malocclusions

These likely occur secondary to the degree to which achondroplasia is expressed within a patient (Proffit 2007), or if early trauma was documented. However trauma tends to occur unilaterally so more commonly causes Class IV malocclusions. For many dogs the achondroplasia gene is expressed to a different degree in different breeds (particularly in

small breeds). Although an autosomal dominant trait, the gene only has only partial penetrance and therefore the trait will be expressed more dramatically in some individuals than others (Proffit 2007). Class II malocclusions are generally present before the eruption of the permanent teeth and as the permanent teeth will start impacting the palate at around six months of age, an early plan for correction is required. As above, severe palatine trauma and/or periodontal disease can result so although animals with Class II malocclusions may not show any obvious clinical signs, they are painful. In addition, traumatic pulpitis of the mandibular canine may result in endodontic abcessation of this tooth (Brine 1999). Typically Class III malocclusions result in little if any trauma to soft tissues but occasionally may cause periodontal inflammation secondary to gingivitis on the lingual surface of the mandibular incisors. Ulceration to the upper lip may also occur. Tooth-to-tooth trauma (attrition) between the mandibular canine and maxillary incisors may be present and require intervention. Attrition may also be seen on opposing incisors and on premolars. Treatment options for Class II malocclusion are similar to Class I. Endodontic therapy (crown reduction and vital pulpotomy) is usually the treatment of choice with orthodontics sometimes an option. A recommendation to neuter is almost always advisable with Grade II malocclusion. Though the genetic component associated with achondroplasia and other genetic effects is hard to truly quantify, the dominant effect of this gene should not be ignored. Often, treatment of Class III malocclusion is not needed, other than intermittent review. However endodontic or extraction therapy may be indicated if there is impingement or wear of soft or hard tissues. Occasionally orthodontic therapy is an option in mild cases.

Class IV malocclusions

This occurs when there is a shift in the mandibular midline due to one mandible being shorter than the other and neither is the same length as the maxilla. Aetiology is considered similar to Class II/ III malocclusions.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Damage to the soft tissue of the palate, gingiva or lip of the maxilla (as a result of the uneven occlusion in one or both of the lower canines) can cause periodontal disease, oronasal fistulas and traumatic pulpitis. This is a source of significant discomfort even in the absence of obvious outward clinical signs. Where treatment is indicated, crown reduction and vital pulp therapy is usually an option alongside selective extractions or orthodontics in more mild cases. There are an enormous number of species and breeds that are encountered in veterinary practice which makes for a huge variation in occlusion and/or malocclusion. Thorough examinations can afford an animal a better quality of life through careful planning with the client to address any potential occlusive issues sooner rather than later in life.

References

Anonymous. Malocclusions and Orthodontics in Dogs and Cats. http://www.avdc.org/ malandortho.html (accessed 5 May 2016). American Veterinary Dental College, Meridan, ID, USA, 2016 Bellows J. Orthodontic Equipment, Materials and Techniques. Blackwell Publishing, Ames, IA, USA, 2004 Brine E. Endodontic disease of the mandibular first molar tooth secondary to caudal cross bite in a young Shetland Sheepdog. Journal of Veterinary Dentistry 16, 15–8, 1999 Gawor J. Veterinary Orthodontics. Practical Veterinary Publishing, San Diego, CA, USA, 2013 Hale F. Juvenile veterinary dentistry. Veterinary Clinics of North America; Small Animal Practice 35, 789–817, 2005 Harris EF, Johnson MG. Heretability of craniometric and occlusal variables: a longitudinal sib analysis. American Journal of Orthodontic and Dentofacial Orthopedics 99, 258–68, 1991 Harvey CE and Emily P. Occlusion, occlusive abnormalities, and orthodontic treatment. In: Harvey CE and Emily P (eds). Small Animal Dentistry. Pp.

266–96. Mosby, St Louis, MO, USA, 1993 Niemiec B. Pathology in the pediatric patient. In: B. Niemiec (ed). Small Animal Dental, Oral and Maxillofacial Disease - A Color Handbook. Pp. 90–126. Manson, London, UK, 2010 Proffit W. Contemporary Orthodontics 4th ed. Mosby Elsevier, St Louis, Mo, USA. 2007 Ross D. Orthodontics for the dog: Bite evaluation, basic concepts and equipment. Veterinary Clinics of North America: Small Animal Practice 16, 955, 1986 Roux P, Howard J. The evaluation of dentition and occlusion in dogs. Journal of Companion Animal Practice 20, 241¬–51, 2010 Shipp AD, Fahrenkrug P. Orthodontics. In: Shipp AD and Fahrenkrug P (eds). Practioner's Guide to Veterinary Dentistry. Pp. 117–47. Griffin Printing, Glendale, CA, USA, 1992 Tutt C. Small Animal Dentistry, A Manual of Techniques. Wiley-Blackwell, Ames, IA, USA, 2007 Wiggs RB, Lobprise HL. Veterinary Dentistry; Principles and Practice. Lippincott-Raven, Philadelphia, PA, USA, 1997 l

The Nobel Prize-winning G-man is dead Alfred Goodman Gilman died in December 2015. Generations of Massey veterinary students will know his name through the pharmacology text "The Pharmacological Basis of Therapeutics" but it was his father Louis Gilman who, together with close colleague Louis Goodman, authored the first editions of this text. So Arthur came from scientific aristocracy and developed into an outstanding pharmacologist himself. He devised a mechanism for detecting the intracellular messenger cAMP and went on to discover the link between catecholamine hormone receptors in the cell membrane and their intracellular signalling mechanisms, with colleague E.M. Ross. They called this G-protein and further described its structure and DNA sequence. For these investigations he shared the Nobel Prize for Medicine or Physiology with Martin Rodbell who had

predicted such a linkage. Numerous heterotrimeric G-proteins have since been identified, and the understanding of their roles has expanded to almost all physiological processes in organisms ranging from yeasts to mammals. Louis Gilman edited the pharmacology text that intimidated me as a student but Alfred edited a number of later editions. I think it is up to 13 now. A Nobel achievement! There are some cool videos online (google G protein) for those of you who would like to remind yourselves about how the G-proteins work. Lefkowitz RJ. Obituary: Alfred Goodman Gilman (1941–2015). Nature 529, 284, 2016

Allan Bell

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

FEATURE ARTICLE

Feline hyperthyroidism – guidelines for management and other information BOYD JONES ONZM, BVSc, FACVSc,

DipECVIM-Ca

The Journal of Feline Medicine and Surgery published the American Association of Feline Practitioners’ (AAFP) Guidelines for Management of Hyperthyroidism (FHT) in the May 2016 issue (Carney et al. 2016). The editorial (Carney and Ward, 2016) emphasized that the earlier diagnosis of FHT has changed how we treat cases, and the presence of concurrent diseases has altered the approach to treatment. The advisory panel included primary and referral clinicians from feline practices and feline/canine practices. The editorial concludes with: ‘FHT is a disease of senior cats that, more often than not, we can cure or successfully manage thanks to better awareness, routine screening tests and a variety of readily available treatment options. It is our hope that these AAFP Guidelines will help clinicians accomplish this goal.’ It is not the purpose of this short summary article to review the whole paper, but I have selected some areas that I thought might be of interest to practitioners in New Zealand and some that I find of particular interest. The authors noted that there are numerous recent reviews of the history, pathogenesis, epidemiology and incidence of hyperthyroidism and readers are referred to these papers (Peterson 2012: McLean et al. 2014; Peterson 2014). The authors have produced the Guidelines to reflect current evidence-based knowledge. If research was lacking or if a consensus did not exist, the expert panel made recommendations based on their cumulative clinical experience and knowledge of the disease. I do note that the Guidelines reflect experience of experts domiciled in the USA. No references or experience of FHT from New Zealand are recorded. I have included direct extracts from the paper in box format. The majority of hyperthyroid cats have bilateral disease. Early experience indicated that removal of a functional adenoma might be followed by development of a contralateral one. If ablative surgery or radioiodine was not chosen for management of the initial mass, scintigraphic evidence suggested that the adenoma could continue to grow, possibly leading to malignancy as occurs in human patients. Of importance to the practitioner, only 2% of hyperthyroid cats have malignant carcinomas at the time of initial diagnosis.

Contact: IVABS, Massey University, Palmerston North

We do not yet have a clear picture of the causes of FHT in its current presentation. Multiple factors play a role but the relative importance of each is unknown. Our current understanding can be summarised as follows. Genetics may influence susceptibility: in one study, Siamese and Burmese breeds had a decreased risk of developing the disease. Changes in cat husbandry since the 1970s to the present day, including a higher percentage of indoor cats, increased utilization of commercial cat foods and longer life spans, may influence the prevalence. Age has long been understood to be a risk factor for thyroid nodule development in humans. Bilateral disease strengthens the hypothesis of dietary and environmental etiologies rather than mutational causes alone. Epidemiologic studies have produced a list of ‘guilt by association’ compounds, many of which are phenols or halogenated hydrocarbons. More hyperthyroid cats use deodorized kitty litter and/or eat food from cans that may contain bisphenol A and phthalates. Soy isoflavones, a component of many cat foods, and the common environmental contaminant fire-retardant PBDEs (polybrominated diphenyl ethers) may act as goitrogens via thyroid-stimulating hormone (TSH) stimulation or as direct mitogens. Variable iodine content of cat foods also seems to have an influence on the development of the disease. Because no studies have prospectively evaluated lifelong exposure to a specific compound in hyperthyroid cats, advise cautious cat owners that all associations are conjecture, and not proven fact. The epidemiological study of cats in New Zealand by Olczack et al. (2005) provides a perspective on the disease in this country. Recently, Burchell (2016) provided a thoughtful and reasoned argument for a genetic cause. We will wait for the final verdict.

Diagnosis

The section on diagnosis was not contentious but the authors emphasized that FHT may be complicated by concurrent diseases with the common co-morbidities being; hypertension, retinopathy, CKD, insulin resistance, gastrointestinal disease (cobalamin deficiency) and thyrotoxic heart disease.

Myths and realities of hyperthyroidism treatment

The authors of the Guidelines provided information on a variety of contentious aspects of FHT – some myths and realities of treatment of hyperthyroidism. Here are the myths and realities! Importantly the authors emphasized again that evidence-based data should guide treatment.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

MYTH: Methimazole causes kidney damage FACT: Treatment of FHT does not cause kidney damage or renal failure regardless of treatment modality. Side effects of each treatment modality have been described in numerous texts, and none cause direct damage to the kidneys. Treatment of FHT by any means can ‘unmask’ pre-existing CKD, thereby giving the impression of causality where none exists MYTH: Maintaining T4 slightly above the reference interval will help patients with comorbidities like CKD. This ‘renal-protective’ effect is assumed to be the result of improved appetite and increasing blood flow to the kidneys. FACT: This myth is now known to be untrue. On the contrary, left untreated, even mild FHT can cause or exacerbate CKD and glomerular damage; hypertension and proteinuria are possible mechanisms. Early treatment can help reduce damage to the kidneys from hyperthyroidism. Furthermore, unregulated FHT induces a catabolic state that creates a false sense of security in the patient’s health and masks clinical signs of comorbid disease due to increased appetite and activity level. In addition to the negative energy balance created by the catabolic state, increased gastrointestinal transit times and malabsorption contribute to a negative energy balance. MYTH: Cats with creatinine concentrations within the reference interval do not have CKD FACT: Increased GFR and cachexia will artificially lower serum creatinine values in spite of significant renal disease. Monitoring body condition score and muscle condition score will better evaluate whether sarcopenia has occurred. The Panel recommends using the IRIS guidelines for staging, monitoring and treating CKD. MYTH: Isolation after 131I administration is too stressful for the cat FACT: Although any time a cat is away from home it may experience stress, this stress is much less than the stress of the illness of other treatment. It is important to fully explain to the owner that any illness and treatment can be stressful and the risks of treatment must be weighed against the benefits. 131 I may actually be the option best tolerated by the patient. Hospitalisation for 131I is similar to what a cat experiences when boarding when the owner is on vacation. Often the cat is less stressed than the owner fears, and most cats tolerate the required post-treatment isolation reasonably well. Many facilities are addressing the environmental needs of cats with improved mental and physical stimulation during their stay. With availability of scintigraphy and a better understanding of dose titration of 131I, radiation safety can still be ensured with relatively short stays in the hospital. Many stays are shorter than would be required to treat some of the complications associated with poorly controlled FHT.

MYTH: Post treatment T4 should be below the reference interval because producing a hypothyroid state does not harm cats. The patient is not clinically hypothyroid as long as the T4 is in the reference interval and the patient gains weight. FACT: Cats can develop clinically significant hypothyroidism even if the T4 is within the reference interval. While treatment of hyperthyroidism does not cause or exacerbate renal disease and achieving a euthyroid state is beneficial to the patient, overtreatment (iatrogenic hypothyroidism) can cause progression of renal disease and increase patient morbidity and mortality. Newer data suggest that using canine endogenous TSH as a means of ruling out iatrogenic hypothyroidism can be beneficial in optimizing outcome. One study determined that 20% of cats treated for FHT were iatrogenically hypothyroid, and twice as many cats with elevated TSH were azotemic compared with cats without elevated TSH. The goal remains to establish a T4 in the lower half of the reference interval but to ensure a normal (nonelevated) TSH. The patient should show concurrent clinical improvement. Normalised T4 without improvement in clinical signs warrants further diagnostic evaluation.

Whether the cost of radioiodine treatment or cost of feeding y/d (Hill’s Pet Nutrition) for cats in in New Zealand produce the same cost relationship, readers will need to determine for themselves before advising their clients of the most cost effective treatment for cats in this country.

Treatment approaches Most clinicians recommend definitive therapy with radioactive iodine or thyroidectomy, especially if the cat is fairly young and otherwise healthy. However, in the case of geriatric cats, cats with concurrent non-thyroidal disease (especially CKD) and cats whose owners decline definitive therapy, the long term administration of the antithyroid drugs methimizole and carbimazole or an iodine restricted diet are options. In addition, pretreatment with methimazole or carbimazole, to restore euthyroidism prior to surgery is a common practice for cats. Hyperthyroid cats at increased risk of complications, including those with cardiovascular disease or severe hyerthyroidism, may benefit from treatment with methimazole or beta-adrenergic antagonists before definitive treatment with radioactive iodine or surgery.

The advantages and disadvantages of the different treatments for hyperthyroidism are listed in Table 1. This chart may be downloaded from www.catvets.com/hyperthyroidism for use with clients, and is also available as supplementary material at http://jfms.com. DOI:10.1177/1098612X16643252

MYTH: The cost of 131I is prohibitive FACT: Over the life of the patient the cost of treating uncomplicated FHT is similar if one chooses radioactive iodine, medication or surgery. The cost of feeding y/d each year is approximately the same as the cost of any of the other three options. The cost of radioiodine or surgery is borne up front, while the costs of oral antithyroid drug therapy and dietary therapy are separated over time. 26

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Table 1. Advantage and disadvantages of treatments for FHT

Treatment Radioactive iodine

Advantages - kills abnormal cells in any location - cure rate ≥95%; most successful treatment for carcinoma - relapse rate 5% - simple treatment – one injection or oral capsule - serious side effects are rare - limited testing needed after successful treatment - minimal risk of permanent hypothyroidism - preferred method for humans

Oral or transdermal medication

- response rate ≥95% while on medication - small pills, liquid or topical gel - requires no hospitalization - no risk of permanent hypothyroidism - reversible if kidney function declines

Surgical thyroidectomy

- ≥90% cure rate if both glands are removed - 35–60% cure rate if one gland is removed - relapse rate 5% if bilateral procedure; ≤ 30% if unilateral - requires no special equipment - most general surgeons can perform

Dietary therapy

- only a change in diet is required - response rate ≥82% while on diet - safe in cats with renal insufficiency

The New Zealand experience There are a number of papers published on FHT from New Zealand. The disease was first identified by Jones and Johnstone in 1981. A review of the then current status (Labuc and Jones, 1988), and a description of radioactive iodine treatment (Jones et al. 1991) were published subsequently. The most significant paper from New Zealand was the epidemiological study of hyperthyroidism by Olczack et al. (2005).

In the 1990s, Tartellin et al. (1992) and Kyle et al. ( 1994) investigated the dietary iodine content of pet foods fed to cats in New Zealand and the effect of feeding these foods on thyroid function. Readers are referred to these papers if interested.

Summary points

Veterinarians may have their own views on FHT. Some of the outcomes of the consensus have been provided in this summary. You may or may not agree 28

Disadvantages - requires special licence and facility - hospitalization varies from 3 days to 4 weeks depending on dose cat receives and regional regulations - owner cannot visit - cat is under ”house arrest” for 2 weeks after discharge - owner must collect wastes for 2 weeks after discharge - owner cannot cuddle cat for long intervals for 2 weeks after discharge - not reversible - relapse rate 100% when off medication - daily medication (usually twice daily) for the rest of the cat’s life - frequent lab tests to monitor effectiveness and safety - drug reactions occur in up to 25% of cats: facial itching, vomiting, liver failure, abnormal blood cell levels and bleeding episodes may occur - tumour continues to grow and may become malignant - general anaesthesia in a cat with a compromised cardiovascular system is risky - may damage parathyroid gland and cause transient or permanent calcium crisis - requires hospitalization - not reversible - most cats require stabilisation first with medication - voice or purr may change - absolutely the only food the cat can eat for the rest of its life - only low-iodine treats and water can be used - relapse rate 100% when off diet

with their summary decisions below. If you want to read the full paper, do so, as I have only selected some sections for this summary. There is an excellent client brochure published with the paper which can be downloaded from www. catvets.com/guidelines/client-brochures  Feline hyperthyroidism (FHT) is increasing in prevalence and is now the most common endocrine disorder in middle-aged and older cats, occurring in about 10% of US feline patients over 10 years of age  No one has verified any definitive cause, although epidemiological studies suggest both genetic and environmental influences  Feline geriatric screening panels now routinely include serum T4, which allows detection of elevated T4 levels at an early stage in disease progression and helps enable timely diagnosis and intervention

 Because older age is a risk factor for FHT, clinicians should anticipate the presence of other age-related comorbidities such as heart disease, diabetes mellitus, gastrointestinal dysfunction and CKD in a certain percentage of hyperthyroid patients. FHT case presentations may be ambiguous due to the presence of concurrent diseases or diagnostic inconsistencies  The four common therapeutic modalities, implemented individually or in combination, are radioactive iodine, pharmaceutical therapy, surgical thyroidectomy and dietary therapy  Because FHT is life-threatening, the Panel recommends treatment of all hyperthyroid cats with concurrent management of any comorbidities

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

 Overall success of management of FHT is 83–99%, depending on the patient’s clinical status and treatment modality. Radioiodine and surgery are potentially permanent cures for both adenomas and carcinomas. Methimazole/ carbimazole and dietary therapy will control clinical disease in milder cases and in cats with significant comorbidities  Regular monitoring of a hyperthyroid cat is important not only to assess therapeutic efficacy but also to detect iatrogenic hypothyroidism and to confirm comorbidities that become evident with resolution of the hyperthyroid state  Morbidity and mortality in the wellmanaged hyperthyroid cat are more strongly influenced by the presence and severity of the comorbid disease than by FHT itself.

References

Burchell RK. Putative molecular pathogenesis of feline hyperthyroidism – sifting through the signal transduction crosstalk. Proceedings ANZCVS Small Animal Chapter, Pp 1–5, 2016 Carney HC, Ward CR. Dispelling the myths and providing a way forward for the hyperthyroid cat. Journal of Feline Medicine and Surgery 18, 371, 2016 Carney HC, Ward CR, Bailey SJ, Bruyette D, Dennis S, Fergusson D, Hinc A, Rucinsky AR. 2016 Guidelines for the management of feline hyperthyroidism. Journal of Feline Medicine and Surgery 18, 400–16, 2016 Jones BR and Johnstone AC. Hyperthyroidism in an aged cat. New Zealand Veterinary Journal 29, 70–2, 1981 Jones BR, Cayzer J, Dillon EA, Schmit K. Radioiodine treatment of hyperthyroid cats. New Zealand Veterinary Journal 39, 71–4, 1991 Kyle AH, Tartellin MF, Cooke RR, Ford HC. Serum free thyroxine levels in cats maintained on diets relatively high or low in iodine. New Zealand Veterinary Journal 42, 101–3,1994

Labuc RH, Jones BR. Feline hyperthyroidism. New Zealand Veterinary Journal 36, 71–81, 1998 Mclean JL, Lobetti RG, Schoemann JP. Worldwide prevalence and risk factors for feline hyperthyroidism: a review. Journal of the South African Veterinary Association 85, 1097, 2014 Olczak J, Jones BR, Pfeiffer DU, Squires RA, Morris RS, Markwell PJ. Multivariate risk analysis of risk factors for feline hyperthyroidism in New Zealand. New Zealand Veterinary Journal 53, 53–8, 2005 Peterson ME. Hyperthyroidism in cats: what’s causing this epidemic of thyroid disease and can we prevent it. Journal of Feline Medicine and Surgery 14, 804–18, 2012 Peterson ME. Feline hyperthyroidism: an animal model for toxic nodular goiter. Journal of Endocrinology 223, T97–T114, 2014 Tartellin MF, Johnson LA, Cooke RR, Ford HC, Feek CM. Serum free thyroxine levels respond inversely to changes in levels of dietary iodine in the domestic cat. New Zealand Veterinary Journal 40, 66–8,1992 l

DID YOU KNOW?........... You can access useful articles from the New Zealand Veterinary Journal, grouped by subject from the NZVA Resource page? Go to http://www.nzva.org.nz/?page=resourcecentre, then click on ‘Our Publications’ and select ‘Browse selected papers in the article collections’ under New Zealand Veterinary Journal. There you’ll find a series of collections covering a variety of topics of particular interest to veterinary clinicians including Companion Animals. Each topic contains review articles, scientific articles and clinical communications that have been published in the NZVJ, mostly since 2010. Just select a topic and you will find the title of the articles with a direct link for downloading the paper from SciQuest

Would you like to see your pet on the cover of Companion Quarterly? We now have a new cover photo for each issue of Companion Quarterly. This means we are always on the lookout for suitable photos. Photos selected for the cover must be landscape orientation (or able to be cropped to this), crisp and well focused, and of high resolution (at least 300 DPI). They must also be well composed and interesting. Please send any suitable images to the Editor (sarah.fowler@gmail.com). If however you have a favourite snap of your fur-family that’s not quite up to cover standards, please send that in too: photos that are not selected for the cover may be printed on the back inside cover.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

FEATURE ARTICLE

How I manage recurrent luxation of the coxofemoral joint This article was written as part of the requirements of receiving the Hill’s Pet Nutrition/CAV Educating the Educators Scholarship

ANDREW WORTH BVSc, PGDipVCS, FANZCVS, PhD. Registered Specialist in Small Animal Surgery, Associate Professor, Massey University Traumatic coxofemoral luxation is a common injury following road traffic accidents. Patients should be assessed for other injuries. Whilst not an emergency per se, reducing the hip should be a priority once the animal is stabilised. Some authors state that closed reduction is easier to perform within the first 72 hours and that delayed reduction carries a greater likelihood of reluxation. Additionally a luxated hip is very painful and ongoing cartilage damage may preclude later reduction.

Diagnosis of coxofemoral luxation

The coxofemoral joint is primarily stabilised by the joint capsule and the ligament of the head of the femur (capital ligament). Secondary stabilisation is provided by a fibrocartilagenous extension of the acetabular rim (dorsal labrum) and a ventral ligamentous band that encloses the ventral acetabular notch. Coxofemoral luxation is the most common dislocation encountered in small animals and is almost exclusively seen in mature animals after closure of the proximal femoral physis. In an immature animal with open physes the same degree of trauma will cause a separation of the physis (Salter-Harris fracture) as the physis is weaker than the primary stabilisers of the hip joint. As Contact: Massey University Veterinary Teaching Hospital, Private Bag 11222, Palmerston North 4442

coxofemoral luxation is most commonly caused by external trauma there may be significant concurrent injuries. The patient should be closely examined for chest or abdominal trauma and a neurological examination performed. In animals with isolated luxation of one coxofemoral joint the animal is typically ambulatory on the other three limbs. Cranio-dorsal luxation (of the femoral head relative to the acetabulum) is the most common with ventral and caudal luxation much rarer. The latter may be associated with concurrent avulsion fracture of the greater trochanter. On presentation the animal is typically non-weight-bearing on the affected limb which is held in external rotation and adduction. On palpation there is disparity between the bony landmarks of the ilial crest, the point of the ischium and the greater trochanter. These three points can be compared on either side of the patient and normally describe a triangle. In a craniodorsal luxation the greater trochanter is closer to the ilium and further from the ischium and closer to a line between then, therefore the triangle is more symmetrical and lower (less deep). Manipulation of the hip is typically painful and crepitus may be detected. A useful test of coxofemoral joint integrity is to place a thumb in the notch between the ischium and greater trochanter. External rotation of the femur brings the greater trochanter caudally pivoting on the acetabulum. Pressure is exerted on your thumb which displaces it out of the notch. This is sometimes referred to as the “pinch test”. If the coxofemoral joint is luxated or there is a femoral head or neck fracture there is no fulcrum so no pressure is exerted and there is no ‘pinch’. A further

test I find useful is to stand behind the patient and lift the legs and extend them backwards. The length of the legs is then compared and a cranio-dorsally luxated limb is shorter. Radiographs can be used to confirm the direction of luxation and are also required to detect the presence of intra-articular fracture and any hip dysplasia. The joint capsule can tear mid distance (type I), close to the origin (type II) or close to the insertion on the femoral neck leaving a complete “sock” of joint capsule (type III). Dogs with significant hip dysplasia (CHD) are more prone to luxation following trauma and may warrant additional surgery. Radiographs are also important to rule out concurrent femoral head or neck fracture.

Treatment options for coxofemoral luxation

Coxofemoral luxation should be considered a matter of urgency and reduction should be attempted as soon as the patient is deemed stable. Persistent luxation leads to tightening of the gluteals which will make subsequent reduction more difficult. In addition there can be cartilage damage from prolonged contact between the dorsal acetabular rim and femoral head. Chronic luxation may lead to such severe wear of the head and rim that the hip is not stable after luxation. Whilst it is evident that closed reduction is less successful the longer the hip has been luxated, it is always worthwhile attempting closed reduction. If closed reduction fails then surgery is indicated. I always attempt closed reduction (and an Ehmer sling or strict confinement) regardless of the length of time luxated (within reason!!).

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Closed reduction

Closed reduction should only be attempted under general anaesthesia to a surgical depth as muscle relaxation is required. An assistant should provide counter-traction with a towel wrapped around the down-side leg and pulled opposite the person attempting reduction. The affected leg is externally rotated to disengage the femoral head from the ilium then the leg is placed in traction. The femur is then abducted and internally rotated. After the hip is reduced the femoral head should be rotated and pistoned in and out of the socket to try to eject any blood clots and invaginated joint capsule. The hip should be assessed for stability by attempting to reluxate the hip in the direction it was formerly luxated. The greater the stability that can be appreciated, the better the chance of a successful outcome following closed reduction and placement of an Ehmer sling. Always take a radiograph after sling application (usually a single lateral is fine and avoids too much rolling of the patient). Correct application of an Ehmer sling is paramount to avoid complications such as ischaemic necrosis of the skin of the tarsus or laceration to the inguinal skin. The sling should be monitored by the owner every day and at your clinic every 2–3 days. After 10–14 days, or earlier if there are complications, the sling is removed and the patient is confined for a further 2 weeks. Success rates of as low as 30% and as high as 85% have been reported. Chronicity and poor coxofemoral conformation make reluxation more likely. If the girth of the animal’s thigh muscle prevents a stable sling, pulling the affected leg cranially and bandaging it against the thorax may work. Cats do not tolerate an Ehmer sling well, but they will sit for extended periods with the hip flexed when they are confined to a cage. Rather than struggle to get an effective Ehmer, I consider closed reduction followed by rest for 2 weeks in a small cage in feline patients. When a hip reluxates in a feline patient and the owners cannot afford surgery, is it acceptable to leave the cat without treatment? A study from Norway on free-ranging cats with untreated coxofemoral luxations found that all the owners surveyed felt their cat had acceptable limb function (Perez-Aparicio and Fjeld 1993). This result could be 34

heavily biased due to reluctance/inability of the owner to afford a femoral head and neck ostectomy (FHNO). Indeed, of those re-examined 66% had lameness and 50% had pain on palpation. The best results where seen in animals with long-standing luxation of long-duration in which a neoarthrosis had developed. A complete neoarthrosis was more likely to form in animals injured when very young. In the study, 24/79 of the cats were euthanased soon after diagnosis meaning that even these figures are biased towards those cats that were coping the best. I believe there is an ethical dilemma here; leaving the cat in pain whilst hoping for an eventual outcome that is acceptable, but with a real risk of ongoing pain and dysability. If conservative management is undertaken I believe it is the veterinarian’s responsibility to provide sufficient analgesia and monitoring to ensure the welfare of the patient. Should the cat not be coping well, then FHNO would be indicated. In general a FHNO is a successful procedure when correctly performed. But it is not a substitute for a normal hip joint. In a study by Berzon et al. (1980) 73% of cats had a restricted range of motion, 47% had muscle atrophy and 27% had pain on passive movement following FHNO. Therefore whenever possible attempts should be made to stabilise a luxated hip and not perform a FHNO as an easy option. Cats respond well to many of the intra and extraarticular techniques detailed below.

Surgical intervention

Surgical intervention is warranted when reluxation recurs, when there is acetabular or femoral head fracture or when an animal has other orthopaedic disease and will need to weight-bear quickly on the luxated leg to spare other limbs. There are extra-articular and intraarticular techniques. Extra-articular techniques Closed reduction can be augmented by De Vita pinning where a Steinman pin is passed from below the point of the ischium, across the dorsal aspect of the femoral neck and embedding it in the ilium. The pin is inserted through a stab incision below the lateral edge of the ischium and advanced slowly through the tissue. Placing the pin more medially increases the risk of injury to the sciatic nerve. A threaded pin may provide better initial anchorage but it increases

the risk of sciatic nerve injury. Despite a reasonably high success rate (73%) of an ischioilial pin, the complication rate was high (32%) in one study, and included pin migration, sciatic nerve injury, jont sepsis, and damage to the femoral head. I personally do not use De Vita pinning except in cases of recurrent luxation when the owner cannot afford open reduction and internal stabilisation. As it can be performed transcutaneously and is relatively rapid to perform, it is more affordable than safer operative alternatives. It can be difficult to seat the pin in the ilium in dogs without much lateral flaring of the ilial wing. Such straight pelvii are unsuitable for DeVita pinning. In one small study pin migration was prevented by the implantation of ESF clamps on the pin either side of the ilium. Open reduction is utilised after failure of closed reduction, cases with radiographic evidence of an intraarticular fracture, or in animals with orthopaedic injury to the other hindlimb that will necessitate load sharing on the luxated hip. There are several options for stabilisation after open reduction, either intra-articular of extra-articular in nature. When the joint capsule is minimally injured and the rent is easily reachable, primary capsulorrhaphy may be sufficient. This is especially applicable to type III joint caspule tears. When the attachment to the femoral neck has torn circumferentially leaving a sock of capsule, the femoral head will not go back through the mouth of the sock without open reduction. The sock opening may need to be stretched to accommodate the femoral head and neck back through, but once reduced the hip is typically very stable. Suturing the capsule to adjacent periosteum or femoral muscle bellies is then performed to complete the repair. In cases of type I and II capsule tearing there may be less intact capsule to work with. Dorsal rim augmentation involves the placement of suture anchors along the dorsal acetabular rim. A hole is then drilled through the greater trochanter above the intertrochanteric fossa. Suture material is then passed through the anchor, through the femoral tunnel, then tied, and a second suture is placed after the first. Suture material can be heavy gauge nylon, leader line, or my preference a braided nonabsorbable such as LigaFiba (Veterinary

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Instrumentation UK, Jorvet). With the latter, aspetic technique is paramount to avoid infection. Ileo-femoral suture (internal suturesling) is a versatile technique for craniodorsal luxation that is easy to perform. A standard cranio-lateral approach to the hip is performed (Piermattei 1993). The acetabulum is visualised through the joint capsule rent and flushed and suctioned to remove clots. The luxation is reduced and the joint capsule is sutured. The origin of the rectus femoris muscle, just cranial to the acetabulum, is identified. The ventral edge of the ilium, rostral to this insertion, is cleared with a periosteal elevator. A drill hole if created though the edge of the ilum in a dorso-lateral to ventro-medial direction. A second tunnel is drilled through the cranial aspect of the greater trochanter. A prosthesis is the passed from dorsal to ventral through the ilium, from cranial to caudal through the greater trochanter, then back in a figure-8 pattern before being knotted. The leg is held in adduction and internal rotation during knotting. The original description of

the ileo-femoral suture used a nonabsorbable suture such as polyester tape. The suture needs to maintain reduction for 3–4 weeks. After healing of the soft tissues, the prosthesis becomes a limiting factor for full movement and needs to fail to release the internal rotation and adduction. The dog can be encouraged to exercise after the initial period of healing and the prosthesis will soon break, releasing the hip’s full range of motion. Leader line can be used and will reliably break. Martini et al. (2001) have since demonstrated the utility of using 6–8 strands of 2 USP Vicryl. Knotting is more difficult and all strands shoud be checked individually for tension. I have used this absorbable ileo-femoral suture in both dogs and cats with success. Distal repositioning of the greater trochanter can be used to increase the force the gluteals can provide to reduce the hip. Capsulorrhaphy and caudodistal transposition of the osteotomised great trochanter can be used as the sole procedure for repair of coxofemoral luxation. A greater trochanteric osteotomy may also be used to improve

access to the dorsal acetabular rim for anchorate of a suture anchor. Flexible external fixator – this was published as a small clinical case series following development of the technique first on cadavers and then with surgery on healthy dogs that had the primary stabilizers of the hip severed. It consists of two Ellis pins, one inserted in the femur through the greater trochanter in a vertical to caudal orientation and one in the ilium in a vertical orientation. A rubber band is placed tightly around the pins to keep them from separating but provide a flexible hinge. Whilst it seems like it would work well, I have had reluxation occur in both of the animals I tried this technique on (one bilaterally). I do not recommend it over other methods. Intra-articular procedures A trans-articular pin is a relatively simple technique which is particularly suitable for cats in which closed reduction has failed. A 1.6 or 2 mm pin is driven through the femur to emerge at the insertion of the capital ligament. The hip is then reduced and the pin is

Allan Bell Dermvet-online Consultancy service by a Registered Specialist in Veterinary Dermatology (for veterinarians in the South Island and from Wellington as far north as Lake Taupo) For cases where referral is difficult but help is required. Contact dermvet.bell@xtra.co.nz for cost estimates and protocol

Allan Bell BVSc (canineAnimal med) FACVSc Companion Quarterly: OfficialMACVSc Newsletter of the Companion Veterinarians Branch(dermatology) of the NZVA | Volume 28 No 1 | March 2017

driven into the acetabular fossa, being careful to avoid iatrogenic injury to the cartilage. The pin should protrude no more than 5 mm beyound the medial wall of the acetabulum. At >2 weeks the pin can be removed. Sissener et al. (2009) reported a 77% success rate (good to excellent function without reluxation). The technique requires care to avoid complicaitons including cartilage injury, rectal perforation, inducing subluxation, pin migration or breakage. A toggle pin is a popular option as it replaces the torn capital ligament and empirically seems to provide a stable hip. If fluoroscopy is available it can be performed minimally invasively (Serdy et al. 1999). A drill hole is made from the region between the third trochanter and the greater trochanter to exit the femoral head at the insertion of the capital ligament. The drill should be directed using a C-guide with its tip embedded in the ligament remnant. Alternatively the hole can be drilled from in-to-out by externally rotating the femur. This can be difficult to achieve in well muscled patients. A drill hole is then made in the acetabulum within the fossa. The diameter of the hole needs to be large enough to allow passage of the toggle and the suture material to be used as a prosthesis. The toggle is threaded with the prosthesis and passed through the hole. By pulling on the suture the toggle is pulled back against the medial wall of the acetabulum and checked for stability. A wire loop or dedicated suture passer (Veterinary Instrumentation) is then passed from lateral to medial throught the femoral drill hole and the prosthesis is pulled back through the tunnel. The suture is then tied over a polypropylene button or a second drill hole is placed through the trochanter to allow anchorage for the knot. There are commercial toggles on the market but some of these have sharp edges at the eyelet that I believe can result in premature failure of the suture, especially if leader line is used. I therefore prefer to hand-make a toggle as originally described (Fossum 2007). However a study by Baltzer et al. (2001) showed that commercial toggles were more secure than hand-made ones which can adopt a weaker orientation. The choice of suture material is also somewhat problematic. A braided polyester suture is stronger than leader line of the

same diameter and is less likely to fail acutely. Leader line is prone to complete failure if the outer surface develops a defect. A braided suture can suffer outer fibre abrasion without complete failure. However braided sutures are far more likely to collect bacteria from the surgical environment and trigger a wound infection. At the MUVTH we originally used Ti-Cron suture (Covidien) for toggle procedures but after a few infections converted to leader line. When we experienced a couple of acute failures with leader line we then began to perform ilio-femoral sling sutures instead. More recently I have performed some toggle procedures using LigaFiba. This is similar to FibreWire and very strong. When using non-absorbable sutures we follow several precautions of asepsis. We perform a second sterile prep in the operating theatre, apply an adhesive iodine-impregnated incise drape, place an extra fenestrated drape to isolate the area immediately prior to placing the prosthesis and change gloves before handling the implant. Prophylactic antibiotics (high dose cephazolin, I/V) at induction and a 4-day course post-operatively, are warranted given the seriousness of a joint infection. Finally, do not over-tighten the prosthesis, leave a few millimeters of free play to avoid premature failure. To avoid the use of a synthetic implant both a fascia lata strip and a sacro-iliac band have been described but I have not attempted either in my practice. What if a dog has underlying hip dysplasia? When an animal presents with coxofemoral luxation and radiographs show CHD there are two options; a total hip replacement (THR), or a triple or double pelvic osteotomy. A TPO/DPO can be used (in conjunction with an ileo-femoral suture or toggle-pin) when the dog had good limb function prior to the traumatic luxation (Murphy et al. 1997). But if the animal was persistently lame from arthritic changes associated with the dysplasia prior to luxation, then a THR would be a better option. THR are now available for very small dogs and even cats. Selection of repair technique Overall success of open reduction and stabilization appears to be 85–90% with similar success rates for all the various

procedures. If the joint capsule in minimally injured and can be sutured after reduction then I typically perform a primary capsule repair and an ileofemoral suture (with multiple strands of Vicryl). If there is extensive joint capsule tearing and there is good exposure to the acetabulum then I perform a toggle-pin with a non-absorbable suture (LigaFiba). If there is extensive capsule injury and poor exposure I perform a greater trochanteric osteotomy, and either a screw/prosthesis on the dorsal rim or a toggle followed by distalising the gluteals when securing the greater trochanteric osteotomy. Since I have had failures with most of the techniques, I think combinations have their merits. Thanks to Hill’s Pet Nutrition and CAV for helping fund my trip to the 2016 Veterinary Orthopaedic Society Meeting.

References

Baltzer WI, Schulz KS, Stover SM, Taylor KT, Kass PH. Biomechanical analysis of suture anchors and suture materials used for toggle pin stabilization of hip joint luxation in dogs. American Journal of Veterinary Reseach 62, 721–8, 2001 Berzon JL, Howard PE, Covell SJ, Trotter EJ, Dueland R. A retrospective study of the efficacy of femoral head and neck excisions in 94 dogs and cats. Veterinary Surgery 9, 88–92 1980 Fossum T. Small Animal Surgery, 3rd Edtn. Pp 1250–2. Elsevier Mosby, St Louis, MO, USA, 2007 Martini FM, Barbara Simonazzi B, Del Bue M. Extra-articular absorbable suture stabilization of coxofemoral luxation in dogs. Veterinary Surgery 40, 468–75, 2001 Murphy ST, Lewis DD, Kerwin SC. Traumatic coxofemoral luxation in dysplastic dogs managed with a triple pelvic osteotomy: results in four dogs. Veterinary and Comparative Orthopaedics and Traumatology 10, 136–40, 1997 Pérez-Aparicio, FJ, Fjeld TO. Coxofemoral luxations in cats. Journal of Small Animal Practice, 34, 345–9, 1993 Piermattei DL. An Atlas of Surgical Approaches to the Bones and Joints of the Dog and Cat, 3rd Edn, WB Saunders, Philadelphia, PA, USA, 1993 Serdy MG, Schulz KS, Hornof W, Koehler C, Chiu D, Vasseur PB. Closed toggle pinning for canine traumatic coxofemoral luxation. Veterinary and Comparative Orthopaedics and Traumatology 12, 11–9 1999 Sissener TR1, Whitelock RG, LangleyHobbs SJ. Long-term results of transarticular pinning for surgical stabilisation of coxofemoral luxation in 20 cats. Journal of Small Animal Practice 50, 112–7, 2009 l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

FEATURE ARTICLE

Challenges and pitfalls of managing diabetes mellitus This article was written as part of the requirements for receiveing the Hill’s Pet Nutrition/CAV Educating the Educators Scholarship DR PRU GALLOWAY, BVSc MANZCVS FANZCVS, registered Specialist in Feline Medicine, Hill's Pet Nutrition Adjunct Senior Lecturer in Feline Medicine, Massey University Managing diabetes mellitus (DM) is a combination of science (interpreting clinical and lab findings) and the art of clinical decision making (seeing the 'big picture'). Tricky feline diabetics are one of my most frequent requests for phone consultations, so I pricked up my ears at a couple of presentations by Dr Linda Fleeman at the Australian and New Zealand College of Veterinary Scientists (ANZCVS) Science Week 2016. Linda’s PhD was on DM and she runs Animal Diabetes Australia; in her own words she ‘has probably done more glucose curves than any other vet in the world’. Both presentations were relevant to canine and feline diabetics. The first was about hidden Somogyi and the second a dual presentation with Ann Thompson, DACVIM, about the challenges and pitfalls of managing diabetes. This article discusses highlights from these presentations, plus a few tips in italics from my clinical experience with cats. You can read the full articles on the College website (https://www.anzcvs.org.au/chapterinfo/) and visit Linda Fleeman's website at animaldiabetesaustralia.com.au. For a more in-depth discussion about feline DM, I urge you to read the excellent article in the March 2016 CAS newsletter by Boyd Jones. DM treatment goals: • Resolve clinical signs e.g. polydipsia (PD), polyuria (PU) and polyphagia (PP). • Avoid neuroglycopaenia (i.e. hypoglycaemia with neurological signs]) Contact: Catmed Ltd 38

• Avoid complications of DM such as diabetic ketoacidosis. • In cats achieve diabetic remission. In my opinion this is a secondary goal, as many cats do not have a sustained remission. • Last, but by no means least, ensure the owner is happy with the management protocol and their pet's quality of life. If a cat owner can't manage q12 hourly insulin injections and is considering euthanasia; consider glargine q24 hourly (one study has shown this to be as effective as a lente insulin BID). Successful monitoring of DM: • DM is a dynamic disease. • Measurements taken on one day (e.g. glucose curve, water intake) may not be representative of diabetic control on other days. • Monitoring trends is very important; e.g. owner's home monitoring records, body weight, serum fructosamine +/- serial glucose curves. • Review the pet's history and clinical signs carefully. Interpret all other tests in light of these findings. • Encourage owners of diabetic pets to keep a diary at home and bring a copy to each revisit. Record the insulin dose and time of administration, water intake, appetite and food fed, activity level, daily urine dipstick for glucose and ketones, weekly body weight. For examples see http://www.animaldiabetesaustralia. com.au/. Phone apps are also available. • How is the pet doing at home? With good glycaemic control owners often report they ‘have their old pet back’ and that they are active and bright. A cat’s ability to jump can help establish if subclinical diabetic neuropathy has resolved. • What is its appetite like? If normal, DM may be well controlled. If polyphagic DM is unlikely controlled. If reduced, is intercurrent disease such as pancreatitis present? • What is the body weight? Typically diabetics present with weight loss,

• • •

•

• •

•

so weight gain is expected with appropriate insulin doses. Always weigh them at each clinic visit and ideally owners should weigh them weekly at home on suitable scales. For cats and small dogs scales designed for adult humans are not accurate enough, but electronic baby scales work well and are relatively inexpensive. What is the water intake? Water intake over 24 hours correlates positively with blood glucose concentration. A healthy cat on a dry diet drinks 20–30 mL/kg/day and 0–5 mL/kg/day on wet food. If a cat with DM drinks >40 mL/kg/ day, is losing weight or lethargic, its insulin dose probably needs adjusting. Note if the cat has concurrent disease that causes PD, such as CKD, this needs to be factored in. In multi-pet households, microchipactivated self-opening water dishes allow water intake for individual pets to be monitored. Cat and small dog owners need a measuring jug with 10 ml increments. Don't adjust the insulin dose based on a glucose curve alone (unless of course if hypoglycaemia is detected). The two most common mistakes I see in managing feline DM is focusing too much on glucose curves and/or increasing the insulin dose too quickly. Weight gain, improved activity and resolution of PU/PD/PP are all indicators of improved glycaemic control. When this occurs in a cat, the insulin need will usually reduce substantially, and they may go into remission.

Tips for monitoring urine with Ketodiastix: • Monitoring urine for glucose in multi-cat households: put urine soaked kitty litter or soil in a plastic bag, add some water and dip the Ketodiastix in. The sticks are sensitive enough to detect glucose in a pooled sample. • Interpret the results as just positive or negative i.e. there is no important

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

difference between 1+ and 4+ glycosuria. Glucose curves and their limitations: • Assesses nadir and duration of action of insulin. • There is significant day to day variation in curves even with no change in insulin dosing or food intake. • The timing of the nadir can vary significantly from day to day. A single 'spot' check of blood glucose based on the timing of the nadir on a previous curve can be misleading. • Long-acting insulins like glargine; the nadir is often at ~ 12 hours, when the next insulin dose is due, so 12–24 hour curves are needed. • Cats are especially prone to stress hyperglycaemia. Some show obvious signs of stress (hissing, growling) but in my experience others 'internalise' stress without showing obvious clinical signs. To help minimise stress; obtain blood glucose using the pinna prick technique on a marginal ear vein in a quiet ward with a Feliway Diffuser going. Performing glucose curves at home: • Avoids clinic related stressors and is less costly for the owner. • If a curve on one day shows unexpected/confusing results, it is easy to repeat. • Can test blood glucose whenever clinical signs of hypoglycaemia are suspected. • Set clear boundaries; overzealous owners can test too often and start adjusting insulin doses without consulting a vet. This risks missing the 'big picture' and inappropriately changing the insulin dose. One option is to have these owners monitor daily water intake and urine for ketones/ glucose at home instead. Somogyi effect: • Occurs when the insulin dose is too high. • Physiologic response to low blood glucose. • Period of hypoglycaemia can be brief (minutes), often occurs at night and often goes unnoticed. So diagnosis can be challenging. • Release of counter-regulatory hormones (cortisol, glucagon and epinephrine) causes a rebound in blood glucose by causing insulin resistance. • Somogyi occurs if the rebound hyperglycaemia is excessive, and it can last for hours to days. • Neuroglycopaenia signs only occur if the counter-regulatory response fails. Clinical signs include dullness, hiding, pacing, weakness, ataxia, star gazing, vomiting, collapse, seizure and in cats meowing/yowling and dogs trembling.

• Blood glucose curves taken during the day frequently show persistently high blood glucose, indistinguishable from other causes of insulin resistance. This means serum fructosamine is also likely to be high and clinical signs of poor glycaemic control such as PU/PD will be present. • Careful owner questioning may identify a preceding period of ‘good’ control on a lower insulin dose. And/or owners may report unusual behaviours such as night time vomiting/yowling or urinating outside the litter tray. If these early signs are missed, they may present as 'brittle' DM, weight gain with poor glycaemic control or apparent 'insulin resistance' with very variable blood glucose results despite consistent insulin dosing. • Somogyi is more likely to occur when the insulin dose is increased too quickly; allow 1–2 weeks between adjustments in insulin dose. • Small dogs and cats may be at increased risk, as one unit insulin dose adjustments are larger in relation to their body weight. • Using insulin pens allows for accurate insulin dosing especially when doses of 2U or less are used. e.g. Lantus Solo Star for 3 mL glargine cartridges. • Somogyi is easily diagnosed with continuous glucose monitoring systems (CGMS). • Use of CGMS in human diabetics shows nocturnal hypoglycaemia is commoner than previously thought, especially in patients with good glycaemic control. The same is likely in dogs and cats; in the last 5 years at Animal Diabetes Australia almost every hypoglycaemic event has occurred between 12 am and 3 am. • Latest advance in CGMS is ‘flash glucose monitoring’; no lancets, no calibration needed, painless application, cost effective e.g. Freestyle Libre® (Abbott Diabetes Care, Australia) not currently available in NZ, but Abbott are considering making it available. In Aussie the reader costs Aus$95 and the sensor Aus$95. Generates a graph of glucose not actual numbers, provides 8 hours of data. Designed for people and is very accurate in dogs (no published feline data yet). • In the absence of CGMS, the key to diagnosing Somogyi is clinical suspicion (see above). Then reduce the insulin dose and look for signs of improved glycaemic control. Often reducing the insulin dose by 0.5–1 U per injection is enough. If clinical signs were previously well controlled on a lower insulin dose, returning to this insulin dose and

monitoring the response for 2 weeks is a reasonable option. Response may be seen immediately or can be gradual over 1–2 weeks. Importantly if Somogyi is not present most dogs and cats will show a worsening of clinical signs within 12 hours. These pets can be returned to their previous insulin dose while other reasons for insulin resistance are investigated. Pru’s tips re: fructosamine: • Fructosamine is a glycated serum protein that forms through an irreversible, insulin independent, non-enzymatic binding of glucose with serum proteins. • It reflects the average blood glucose in the preceding 1–2 weeks. The higher the blood glucose the more fructosamine is synthesised. • Reference ranges differ a little from lab to lab, but levels over 400 μmol/L strongly supports a diagnosis of DM. • False negatives: very recent onset DM, hyperthyroidism and if serum total protein is reduced. • Fructosamine is a useful addition to the diabetes management tool box when used in combination with other tests (history, clinical signs, blood glucose curve). It can be very helpful to identify transient stress hyperglycaemia in the clinic from poor glycaemic control. The former will have a fructosamine in the adequate control range; while in the latter fructosamine will be high. Note that good home monitoring records should tell you this too. • Run the first fructosamine at the time DM is diagnosed. • Following trends over time more helpful than single tests. The aim is a steady decrease towards the normal range. In healthy cats fructosamine is usually lower than ~ 360 μmol/L, well controlled diabetics usually have levels between 350–450 μmol/L, but adequate control is usually achieved with levels in the 450–550 μmol/L range. • High fructosamine supports inadequate glycaemic control, but doesn't tell you if the insulin dose needs increasing or decreasing. For example pets with Somogyi usually have high fructosamine due to prolonged rebound hyperglycaemia. • Don't get too hung up on laboratory reference intervals for ‘ideal ‘glycaemic control. For example if the history and clinical signs are consistent with good glycaemic control (i.e. resolution of PU/ PD/PP, weight stable/increasing and owners are happy with their pet at home) but the fructosamine is in the 500s, I don't usually change the insulin dose. l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

CONFERENCE REPORT

Valentine Charlton Feline Medicine Conference Melbourne, Australia, June, 2016.

ORLA FITZPATRICK, MVB

MRCVS, VetEnt Queenstown

I was extremely fortunate to attend the Valentine Charlton Feline Medicine Conference in June this year. The Conference was organised by the Centre of Veterinary Education (CVE), a centre of the University of Sydney, which celebrated its 50th anniversary last year. The CVE also offers a variety of high quality distance education, a few of which I have completed and highly recommend. The conference was held in the Intercontinental Hotel, Melbourne, Australia and consisted of 4 days of lectures, followed by a more intimate interactive masterclass with the tutors on the final day. Out of the 170 attendees, seven were from New Zealand. The keynote speaker was Susan Little, a highly sought-after speaker. Susan is a board certified feline specialist, President of the AAFP, a consultant for VIN and co-owner of two feline practices in Ottawa, Canada. Susan is also author and editor of many journal articles and feline medicine texts. Andrea Harvey, Carolyn Oâ&#x20AC;&#x2122;Brien, Kath Briscoe, Steven Holloway and Richard Woolley joined Susan to give an excellent conference that was crammed full of information relevant to general practitioners of all levels of experience.

of pain and assessment of pain could be enhanced. Most vets questioned agreed that a pain scale was a useful clinical tool although only a minority were using a formal pain scoring system in their practices. Two feline-specific pain monitoring systems have become available over the last few years (the UNESPBotucatu Multidimensional Composite Pain Scale and Glasgow Composite Measure Pain Scale for acute pain in cats). The Glasgow researchers are currently working on the incorporation of a facial expression component in their system. Veterinary hospitals should have a clear policy regarding assessment of pain in their feline patients, including when assessments are performed, who performs the assessment, what action should be taken if inadequate pain control is determined and when the assessments should be repeated. Free guidelines on pain management have been published by the AAHA and AAFP in 2015. The acronym PLATTER (Plan, Anticipate, Treat, Evaluate and Return)

allows continuous management of both acute and chronic painful conditions until pain is resolved.

Feline osteoarthritis (OA)

Osteoarthritis is very difficult to diagnose on clinical examination of cats. A recent Canadian study (Klinck et al. 2015) assessing the reliability of the Montreal Instrument for Cat Arthritis Testing for veterinary use, showed inconsistencies and difficulties in diagnosing OA using a number of physical findings. The results reaffirmed the importance of pain scales for use by owners in managing feline OA given the uncertainties that remain regarding the interpretation of physical examination findings. North Carolina State University have produced the Feline Musculoskeletal Pain Index for owners to complete. This questionnaire is best filled out by owners at home and can be reassessed during treatment of osteoarthritis as a monitoring tool. Low scores indicate pain which should be addressed appropriately.

The proceedings for this conference and other previous conferences are able to buy on the CVE website: http://www.cve. edu.au/vetbookshop. The following is a summary of a selection of topics covered that I felt relevant to Kiwi veterinarians:

Pain recognition

In a recent study published in the NZVJ by Kongara et al. (2016), a majority of NZ veterinarians admit that their knowledge Contact: orla.fitzpatrick@vetent.co.nz

Susan Little giving a presentation at the Valentine Charlton Feline Medicine Conference. Photo courtesy of Orla Fitzpatrick.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Gut repoopulation

The benefits of faecal transplantations in humans is well known but there is very limited scientific data on their use in veterinary patients to date. Jergens et al. (2016) have published an article on the key aspects of faecal transplantations in small animals in Veterinary Medicine: Research and Reports following last year’s comparative gastroenterology meeting. These transplantations could potentially be an exciting new frontier in the treatment of animals with chronic enteropathies including inflammatory bowel disease (IBD).

Cobalamin supplementation

A large number of cats with IBD have suboptimal serum cobalamin levels and supplementation may be necessary. The Gastrointestinal Laboratory at Texas A&M University currently recommends 250 μg per cat once weekly for 6 weeks followed by one dose 30 days later then retest serum cobalamin 30 days after last dose. A 2016 paper on oral cobalamin supplementation in dogs by Toresson et al. suggests that oral cobalamin supplementation is effective in normalising serum cobalamin concentrations in dogs with chronic enteropathies but more studies are warranted comparing parenteral versus oral supplementation.

Constipation and megacolon

The first step in management of constipation is correction of dehydration with intravenous fluid therapy followed by removal of obstructing faeces. In mildly affected cats, one or two doses of a microenema usually produce results. More severely affected cats will require warm water or isotonic saline enemas (5–10 ml/ kg). Safe additions to the water include mineral oil (5–10 ml/cat) or docusate (5–10 ml/cat). Soaps or detergents are irritating to an already compromised colonic mucosa and could let bacteria across so are not recommended. Very severe cases may require manual disimpaction under general anaesthetic which has risk in geriatric patients. An alternative to this is the GoLytely approach. Administration of an oral polyethylene glycol (PEG 3350) solution trickle fed through a nasooesophageal tube (6–10 ml/kg/hour) over 4–18 hours in a sufficiently hydrated cat will lead to defecation in 6–12 hours. PEG 3350 has also been shown to be safe for longterm management and is a lot more palatable than lactulose.

Cat-friendly clinics

Andrea Harvey is the Australasian representative of the International Society of Feline Medicine (ISFM), the veterinary division of International Cat Care. She is an advocate for cat friendly clinics and encouraged more veterinary clinics to become accredited. Currently there are only five cat friendly accredited clinics in NZ. In 2014 the Australasian Society of Feline Medicine (ASFM) was formed to advance the health and welfare of cats in conjunction with its partner organisation the ISFM. More information on the ASFM and how to gain membership can be found at http://asfm.com.au/. Making changes in our clinics, including our attitude and approach to handling cats, can significantly reduce stress in our patients. Reducing stress will allow easier examinations, easier interpretation of clinical signs, fewer stress-related changes in clinical parameters and allow us to work more efficiently. Happier cats will also give us happier staff due to the reduction in injuries caused by handling fractious cats and showing we care about reducing stress in cats will give happier clients which is good for business. All veterinary clinics have the potential to become cat friendly, even if building size is

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

restrictive, as there are three accreditation levels that can be obtained. Apply for an information pack on how to become accredited including feline friendly handling guidelines with this link: http:// tinyurl.com/isfmcfc.

hyperthyroidism, particularly where they advocate long-term medical management should be discouraged in favour of tailoring management of hyperthyroidism based on patient and client factors with reference to current literature.

Hyperthyroidism

Update on immune-mediated conditions and infectious diseases in cats

Curative treatments are far superior since controlling thyroxine synthesis does nothing to halt the underlying disease process which will continue to progress, management can become more challenging over time and the thyroid is predisposed to neoplastic transformation. The prevalence of thyroid carcinoma is reported to increase from less than 5% to 19% in cats managed with anti-thyroid medication for over 4 years. Cats treated with methimazole have shorter survival times than those treated with radioiodine; client compliance with drug administration, poor titration of therapy and drug toxicosis may be accountable for these observations. Daily control options do have a place in managing hyperthyroidism, for example, stabilising prior to thyroidectomy to reduce anaesthetic risk and if cats have comorbidities that lower life expectancy. It is no longer considered necessary to trial patients prior to radioactive iodine particularly if pre-existing azotaemia is absent. Iatrogenic hypothyroidism contributes to significant changes in renal function so should be addressed. Some performing radioactive iodine treatment supplement cats with thyroxine immediately post-treatment and wean them off treatment over the following 2 months. A survey of Australians veterinarians in the Journal of Feline Medicine and Surgery by Kopecny et al. (2016) reported that radioiodine was more frequently preferred by Australian veterinarians compared with a previous survey of UK veterinarians, yet anti-thyroid medications were still the most frequently used treatment modality. The authors of this study concluded that recent changes to recommendations on the management and monitoring of hyperthyroid cats do not appear to have been widely adopted by veterinarians at this time. Practice policies for management of feline hyperthyroidism were reported by 25% of vets surveyed, the most common policies recommending anti-thyroid medication. Practice policies for management of

From Steve Holloway, a registered specialist in internal medicine at Advanced VetCare, Melbourne. l Feline morbillivirus – Studies in Japan and Hong Kong isolated a number of paramyxoviruses similar to canine distemper found in the urine of cats which are associated with impaired renal function due to interstitial tubular nephritis. Further research may lead to vaccines and possibly a reduction in the prevalence of feline renal disease. l Feline Calicivirus (FCV) – Two Studies in the JSFM in 2016 – a Spanish study of cats with various disease syndromes by Fernandez et al. showed FCV was strongly associated with gingivo-stomatitis. However a contradictory study by Rolim et al. failed to demonstrate FCV in lesions using immunohistochemistry. l Herpes virus (FHV-1) – An article in BMC Veterinary Research by Bol and Bunnik (2015) reviewed previous studies involving lysine and recommended the immediate ceasation of lysine supplementation due to the complete lack of any scientifically proven efficacy. l FIP – Previous studies have shown that the 3C non-structural protein plays an essential role in virus replication. Research by Kim and Pederson (2016) reports reversal of the progression of coronavirus in cats by a broad spectrum protease inhibitor leading to full recovery in 6/8 cats experimentally induced with FIP. Protease inhibitors could be a promising antiviral treatment option. l Feline Leukaemia virus (FeLV) – In a 2015 paper by Nesina et al. (Retroviral DNA – the silent winner: blood transfusion containing latent Feline Leukaemia provirus causes infection and disease in naïve recipient cats) in Retrovirology, 10 cats that received transfusion of blood from aviraemic provirus carriers had developed active FeLV infections which shows the need for provirus PCR-testing of our blood donors.

Feline cardiology update

From Richard Woolley, a veterinary cardiology specialist who owns and operates CardioRespiratory Pet Referrals in Melbourne. l Pimobendan (Vetmedin) – The package insert of pimobendan states that the drug is contraindicated in cases of hypertrophic cardiomyopathy (HCM) due to the fact that it was assumed that there is some degree of outflow tract obstruction in HCM which may be worsened by treatment with pimobendan. A number of retrospective case series studies on cats with HCM that were treated with pimobendan showed increased survival time with no adverse effects unless dynamic outflow tract obstruction was present where hypotension was seen. The dose of pimobendan used by cardiologists in a recent survey is lower than that of dogs (0.25–0.3 mg/kg PO q12 hours) despite no adverse results in clinical studies using similar dose to dogs since pharmacokinetic studies show peak serum concentrations 10 times higher in healthy cats given same dose as dogs. l Clopidogrel – An article reporting the results of the FAT CAT study was published in the Journal of Veterinary Cardiology (Hogan et al. 2015). Clopidogrel administration was associated with a significantly reduced likelihood of recurrent cardiogenic aortic thromboembolism (CATE) compared to aspirin and had a longer median time to recurrence. Clopidogrel treatment was also associated with a significantly reduced likelihood of the composite end point of recurrent CATE or cardiac death with a longer median time to event. Clopidogrel administration significantly reduces the likelihood of recurrent CATE compared with aspirin in cats. Both drugs were well tolerated. l Atenolol – Only of benefit in cats with systolic anterior motion,of the mitral valve and not beneficial in the early stages of HCM and detrimental in cases of congestive heart failure. Special thanks to Veterinary Enterprises for partially funding my conference trip and funding my CVE Feline Medicine distance education course in 2015. References available on request.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

CONFERENCE REPORT

Highlights from the 8th World Congress of Veterinary Dermatology Bordeaux, France, 31 May –4 June 2016 This article is in partial fulfilment of the requirements for the Educating the Educators Scholarship

DUNCAN GRAHAM BVSc, BSc (hons) Duncan Graham has worked as a referral dermatologist for the past 15 years, visiting Palmerston North, Wellington, Christchurch and Dunedin on a regular basis. He can be contacted by email duncan@animaldermatology.co.nz or through the website www.Animaldermatology.co.nz. He has received support through lecturing fees from Royal Canin, Virbac and Hill’s Pet Nutrition. He had a free dinner courtesy of Royal Canin at the 8th World Congress but couldn’t stay for desert. First, there is no comparison. Forget Opryland, forget barbeque, forget the ridiculous Gaylord Convention Centre, Bordeaux is where all conferences should be held. It is a beautiful old city (see Figure 1), freshly polished, but not destroyed by the upgrade, with a fabulous tram system that works brilliantly, in a beautiful area of France, on a working river, and the food and wine are amazing, and not even too expensive for impoverished Kiwis. If you stay away from the high end places that is. True, knowing French would make for a better experience, and there is a certain truculence among the French populace towards those from other countries. However, to be honest, the folk of Bordeaux did not seem like that – they were friendly and understanding of the mangled Franglish that we spoke. For a change, at the 8th World congress of Veterinary Dermatology, there was a very good representation of veterinarians and dermatologists from New Zealand and the usual cohort from Australia. The good news is that the 9th World Congress in Veterinary Dermatology will be held in Sydney in 2020. The conference itself was well organized although there was grumbling from some. The main problem I think was that the organizers hadn’t anticipated that the entry level presentations would be less popular than the higher level and

Figure 1.(a) Place de la Bourse, also known as Place Royale, is one of Bordeaux’s most beautiful squares and a perfect example of Bordeaux architecture at the end of the 18th century. It is seen here reflected in the largest water mirror in the world, the “Miroir des Quais” – “The Quay Mirror”. (b) A bistro dinner in Bordeaux with the kiwi contingent of derm folk with the authors third from right. Photographs courtesy of Mark Edwards

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specialist state-of-the-art presentations. Consequently some of the practitioneroriented lecturers were given in huge amphitheatres to a handful of people while people were turned away from the specialist presentations. The first day of lectures began with the presentation of two consensus statements: one on the Current Status of Diagnosis and Treatment of Dermatophytosis in Companion Animals (Drs Kim Coyner, Susan Paterson and Karen Moriello; Co-Chairs) and another on the Guidelines for Methicillin Resistant Staphylococcal Infections – Diagnosis, Therapeutic Considerations and Prevention (Dr Dan Morris; Chair). The presentations included a summary of key clinical guidelines for each of the topics with an interactive discussion from attendees. Complete manuscripts for each of these topics are available on the WAVD website (www.wavd.org) and comments for the authors can be lodged using the website. These consensus statements are very comprehensive, and are evidence-based. I would encourage everyone to access them online, and print them out for further reference. Here a few bon mots (as we say in Franglish) from the dermatophytosis consensus statement. • Diagnosis: there is no gold standard. All methods of diagnosis have their place. The Wood’s light fared surprisingly well in the literature, as long as it isn’t a little portable, battery operated one, but a mains powered one in experienced hands. • Treatment: topical treatment speeds the time to negative culture, and lime sulphur gets a big tick, as does miconazole/chlorhexidine. In cats, terbinafine at 30 mg/kg once daily with food, or itraconazole at 5 mg/ kg twice daily or 10 mg/kg once daily, also with food, are the treatments of choice. In dogs terbinafine is used at the same dose rate, but itraconazole is given at 5 mg/kg, once daily with food. Itraconazole, because of its long persistence, is sometimes used in a pulse fashion, full dose for one week, followed by one week off.

Infectious diseases Bartonellosis

One of the themes of the congress was infectious diseases. Central to this is the emerging importance of bartonellosis and other arthropod-borne diseases associated with cats and dogs. Ed Breithschwerdt from North Carolina State University gave four lectures on this topic, including a supporting review entitled “Bartonellosis: One Health Perspectives on an Emerging Infectious Disease”. What is a one health perspective? The ‘One Health’ concept recognizes that the health of humans is connected to the health of animals and the environment. It involves applying a coordinated, collaborative, multidisciplinary and cross-sectoral approach to address potential or existing risks that originate at the animal-humanecosystems interface. New Zealand is in the fortunate position of not having many of the vectors of arthropod-borne disease, and specifically is spared most of the tick-borne diseases. Of the non-tick borne diseases, only two species of murine Rickettsia each with its own vectors: (rat flea-borne R. typhi and cat flea-borne R.felis) are found here. However the picture changes with regard to bartonellosis. In his supporting review Breitschwerdt pointed out that “Prior to 1990, there was only one named Bartonella (B.bacilliformis) whereas there are now over 34 species, of which 17 have been associated with an expanding spectrum of animal and human diseases.” Bartonella henselae is an agent of cat-scratch disease, bacillary angiomatosis, bacillary peliosis, endocarditis, bacteraemia, and various neurologic and ocular conditions in humans. Cats are the reservoir hosts, and contact with cats and their fleas is an established risk factor for most infections. Veterinarians and veterinary nurses are particularly at risk for bartonellosis. However, as Breithschwerdt says, the diagnostic detection Bartonella infection by culture or PCR in a non-reservoir adapted sick host can be extremely difficult. Most diseases caused by Bartonella spp. occur in accidental hosts. The ability to invade and infect numerous cell types is a unique feature of this vector-borne pathogen and might partially explain a spectrum of waxing and waning symptoms.

Feline Bartonellosis

Bartonellosis in cats is a perplexing problem. Because B.henselae bacteraemia occurs in 25% to 41% of healthy cats through the world, it was considered previously to be non-pathogenic. However recent data has shown variation in virulence among B.henselae strains Breitschwerdt recommended treating cats with disease manifestations consistent with bartonellosis (fever, lymphadenopathy, mild neurologic signs, and reproductive disorders) in sero-reactive or bacteremic cats. Breitschwerdt reported that experimentally and clinically, doxycycline alone was not an effective antibiotic for elimination of Bartonella infections in cats or dogs. His current regime is weeks of doxycycline at 5 mg/kg BID plus enrofloxacin 5mg/kg SID in dogs, and doxycycline at 5 mg/kg BID plus pradofloxacin at the same dose rate for 6 weeks in cats. This latter drug is not available in New Zealand, but may be available next year. Doxycycline and rifampicin may also be used in dogs, but rifampicin should not be used in cats. Ciprofloxacin should not be used in dogs given the variably poor intestinal absorption. Resistance to azithromycin builds up quickly so it is not recommended for first line treatment.

Bartonellosis in New Zealand

What is the situation in New Zealand? There are three published reports. In 1997 a study of 48 healthy cats from Auckland found 17% had B.henselae bacteraemia. An epidemiological study by Kelly et al. (2005) found that of 114 cat fleas (Ctenocephalides felis) tested, DNA of R. felis was found in 19%, B.henselae in 11%, and Bartonella clarridgeiae in 7%. DNA of these species was not amplified from three dog fleas (Ctenocephalides canis). Their conclusion was that “The emerging human pathogens, R.felis, B.henselae, and B.clarridgeiae, are prevalent and widely distributed in cat fleas in the North Island of New Zealand.” In 2010 Kara Dawson published a great article in the then CAS Newsletter, detailing her research and giving an excellent discussion of B.henselae. Kara tested 70 cats in the Waikato area, finding approximately 10% of them were seropositive. This rate of seropositivity was lower than expected.

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We know from previous studies that seroprevalence occurs at approximately twice the rate of bacteraemia. So given the 17% bacteraemia in the Auckland cats, and the 16.2% bacteraemia in cats from Eastern Australia, it was expected that the seropositivity would be in the 20–40% range. In 2005, there was 5% seropositivity in 40 healthy human blood donors.

Haemoplasmas in New Zealand

Mycoplasma haemofelis (formerly Haemobartonella felis) is another potentially flea-borne bacterium. Haemotropic mycoplasmas (haemoplasmas) are small epierythrocytic bacteria that have the potential to cause severe, lifethreatening haemolytic anaemia. The natural route of transmission of feline haemoplasma infection has not been confirmed, but fleas are implicated. When disease results, common clinical signs are pallor, lethargy, anorexia, weight loss, depression, dehydration and pyrexia. Treatment with tetracyclines or fluoroquinolones is usually effective at resolving clinical disease, but clearance of infection may not result. A 2013 study gave some indication of the prevalence of mycoplasma infection in cats in New Zealand. DNA was extracted from 200 blood samples from cats submitted to a diagnostic laboratory for routine haematology over a 12-month period. Species-specific PCR assays identified 62 cats that were positive for haemoplasma DNA, giving an overall prevalence of 31%.

Take home message:

Here is another reason to emphasize good flea control to your clients. Two laboratory studies have found that flea control prevented cat flea transmission of B.henselae to cats. Good flea control was one of the factors that Kara Dawson thought might explain the lower than expected seropositivity in her study. The other take home message is always consider the other, increasingly common, arthropod-borne diseases in dogs and cats that have resided overseas. It should be noted that Dr Breitschwerdt is the chief scientific officer for Galaxy Diagnostics, a company that provides diagnostic testing for the detection of Bartonella species infection in both animal and human patients. He also coholds a patent for media and methods

for cultivation of microorganisms. His lectures frequently suggest using Galaxy diagnostics and their products.

The diagnosis of cutaneous adverse food reaction (CAFR)

One of the recurring themes of the Congress was cutaneous adverse food reaction (CARF), particularly its diagnosis. Adverse food reactions refer to any clinically abnormal response attributed to the ingestion of a food or food additive. Adverse food reactions are categorized as either food allergy or food intolerance reactions. Food allergy reactions refer to an immunologically mediated adverse reaction to food unrelated to any physiological effect of the food or food additive. Food intolerance reactions refer to any abnormal physiologic response to a food that is not believed to be immunologic in nature and may include food poisoning, food idiosyncrasy, pharmacologic reaction, or metabolic reaction. This definition is taken from an article entitled “The ACVD task force on canine atopic dermatitis (X): is there a relationship between canine atopic dermatitis and cutaneous adverse food reactions?” (Hillier and Griffin 2001). The full text of this article is available online. A dietary elimination trial is still the only reliable way diagnose this entity: intradermal testing, serological testing and gastroscopic food sensitivity testing have all been demonstrated to be inadequate for the purpose (Burrows 2015). The principle is to feed a limited antigen diet, usually a single novel protein and a single carbohydrate, neither found typically in maintenance diets, for 8 to 10 weeks. Most dermatologists consider the homecooked diet to be the gold standard (Burrows 2015). However there are a number of drawbacks to home-cooked elimination diets, not the least being the time factor in sourcing the novel protein and preparing the food. There can be problems with unbalanced diets, particularly in young rapidly growing dogs. More disturbing is the strong possibility of contamination of the novel protein with protein from another meat source during the processing stage, i.e. during the mincing, chopping or storage.

In New Zealand, the greatest problem is the difficulty in finding novel proteins that don’t cross react with other proteins. One presentation at the 8th World Congress, given by Tim Nuttall from Edinburgh University looked at the serological cross-reactivity between beef, lamb and cows’ milk extracts in dogs. The aim of the study was to identify patterns of co-sensitisation and cross-reaction among food allergens. An IgE-based serological assay using 19 food allergens was performed on 469 dogs. Pairwise comparisons suggested significant co-sensitization and/or cross reactions among food allergens. Further testing confirmed that the association among related allergens was the result of cross reactivity rather than co-sensitization. Interestingly, this study was supported by Avacta Animal Health, a company that markets a serological test for the diagnosis of allergies both food and environmental. I asked Tim Nuttal about the usefulness of serological testing for the diagnosis of cutaneous adverse food reactions. He replied that “serology is only useful as a guide to choosing dietary ingredients for a food trial. The work with Avacta (and a new CynoDial test is similar) showed a positive predictive value of approximately 30% and a negative predictive value of approximately 80%. Therefore, the diagnostic value is very low. However, a negative titre can be helpful with the history and knowledge of cross-reactions to select ingredients for a diet trial. This is particularly useful where the choice of diet may be limited for palatability or health reasons.” We should note here that he is repeating Mandy Burrows’ statement that serology testing is unsuitable for the diagnosis of CAFR. Unfortunately the Spectrum IgE test, based in Arizona, is still being used for the diagnosis of food allergy in New Zealand. Mandy Burrows (2015) states that “generally, the closer the taxonomic relationship between meat sources, the higher the risk of cross-reactivity. Allergens from beef theoretically may cross-react with those from other ruminants. Thus, lamb and venison may not be the best unique ingredient protein source because most animals have been previously exposed to beef.” We should note that this is a potential problem, not a proven problem. She

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also warns that there is some evidence of common allergens in avian meats, so duck may not be suitable. Extrapolating from this, it would seem for a homecooked diet in New Zealand, the protein source might be beans, possum, rabbit, possibly fish, and possibly horse meat. Both horses and rabbits are monogastric herbivores rather than ruminants. The appropriate novel protein should be selected based on the animal’s previous diet. Even if home-cooking is the so-called gold standard, it may not be feasible for many clients. What about commercially available over-the-counter (OTC) limited ingredient or novel protein foods? There has been a growing interest by pet owners to use OTC commercial diets for diagnostic dietary trials due to cost and convenience. General practitioners not uncommonly give in to client requests (based on expense or palatability) to use OTC diets when attempting to diagnose food allergy. Such OTC diets are often selected based on the product name (i.e., salmon and sweet potato). Unfortunately regulations only ensure that the product contains at least 3% (not 100%) of those ingredients. For the most part, even if the food carries a claim to be 100% free of anything but the listed single protein, commercial limited-ingredient diets that haven’t been made specifically for the diagnosis of adverse food reactions cannot be trusted. Ricci et al. (2013) found that 10 out 12 diets purported to be ‘limitedingredients’ contained undeclared mammalian and avian DNA and bone fragments. Another study (Raditic et al. 2011) found undeclared beef protein in a solely venison-based OTC product and found soy in three out of four OTC diets that claimed to be soy-free. Their conclusion was “Therefore, if the four OTC venison products selected in this study are representative of OTC products in general, then the use of OTC venison dry dog foods should not be used during elimination trials in suspected food allergy patients.” An even more worrying study found that not only did three out of four OTC diets claiming to have no soy tested positive for soy by ELISA, but some veterinary prescription limited antigen diets also tested positive for soy (Willis Mahn et al. 2013). Several of these were hydrolysed

diets. In humans, hydrolysed soy peptides need to be greater than 20 kDa to trigger an adverse allergic reaction. Until the World Congress, no information has been available for dogs, and the size of the hydrolysed soy protein that can potentially trigger an allergic response was extrapolated from human studies but was thought to be between 18 and 36 kDa. This brings us to the thorny topic of prescription hydrolysed protein elimination diets. A systematic review (Olivry and Bizikova 2010) of the evidence that hydrolysed diets had decreased allergenicity and clinical benefit in dogs with CAFR looked at 11 studies that pertained to that question. Their conclusion was that the evidence pointed to reduced, but not eliminated immunological and clinical allergenicity of hydrolysate-based commercial diets. In three of the studies, up to 50% of dogs with CAFR showed increased in clinical signs after being fed partial hydrolysates derived from foods to which they were hypersensitive. The take home message was that partially hydrolysed diets are probably of most benefit in dogs suspected not to be hypersensitive to the constituent protein. In other words, a dog with a suspected chicken based adverse food reaction should not be fed a hydrolysed chicken diet. At that time there were also no independent studies establishing that a hydrolysed diet could be used as an elimination diet. At the 8th World Congress there was an original supporting study (Diagnostic value of home-cooked and extensively hydrolysed diet in the diagnosis of canine adverse food reaction: a randomized prospective multicentre study in 72 dogs by MC Cadiergues et al.) presented which compared the new, extensively hydrolysed diet made by Royal Canin (Anallergenic) with a home-cooked diet as an approach to the diagnosis of canine adverse food reactions (AFR). Dogs with suspected AFR (n=72) were allocated randomly to either a balanced home-cooked diet (HCD) or the extensively hydrolysed diet (EHD). Eighteen of the 34 dogs (52.9%) on the EHD and 19/35 (54.3%) on the HCD had a reduction in pruritus and clinical signs. In each group 12 dogs relapsed (increased pruritus and worsening on clinical lesions) when the elimination

diets were challenged. A diagnosis of AFR was made in 1/3 of each group, showing that the extensively hydrolysed diet may be as reliable as the homecooked diet. This was an independent study but one of the investigators was a Royal Canin employee. A free communication abstract at the 8th World Congress by Olivry et al. investigated further this question of whether the hydrolyzation of proteins into small peptides would prevent allergen specific IgE from recognizing them. It seems astounding that this hasn’t been done previously since we have been using hydrolysed diets for some years. The objective of the study was whether sera from dogs with high levels of chicken-specific IgE would recognize poultry extracts, either standard or hydrolysed. Nonhydrolysed chicken, duck, turkey and beef (negative control) were tested against non-hydrolysed chicken meal, partially hydrolysed and extensively hydrolysed poultry feather extracts. The results suggested that only extensive hydrolyzation of poultry feather extracts fully prevented IgE recognition of poultry meat allergenic epitopes. Partial hydrolyzation was not enough to prevent recognition. It also gave indirect but further confirmation that antibodies to chicken cross react with other members of the poultry group, duck and turkey. This study was funded by Royal Canin and two of the authors had received salary or funding from Royal Canin.

Final snippets

Frequency of urinary tract infection (UTI) in feline patients with dermatologic disease receiving longterm glucocorticoids and ciclosporin. There was no evidence in this study to suggest receiving long-term glucocorticoids and/or ciclosporin was positively associated with UTI in cats. Studies in dogs have shown that dogs receiving long-term glucocorticoids or ciclosporin have an increased frequency of UTI. This was the first study in cats. There were no positive urine cultures in 33 cats receiving treatment; there was one positive urine culture in the control group of 34 cats.

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Diagnosis of canine atopic dermatitis Of 600 dogs presented to a specialty practice with pruritic skin disease, 300 were eventually diagnosed with canine atopic dermatitis. Of the 300 cases, 225 had a “classic” presentation, using Favrot’s criteria but 75 (25%) did not. Of these 75 cases, relapsing otitis externa without any other clinical sign was seen in 24/75 cases, recurrent hot spots in 8/75, and anal pruritus in 10/75. Surprisingly to me, lesion-less pruritus was reported in only 6/75 cases. Dorsolumbar pruritus was seen in 10/75 cases. Not all cases of dorsolumbar pruritus are FAD. All 75 cases had positive intradermal testing with no significant difference in response to immunotherapy. This supports the idea that the clinical presentation of atopic dermatits is complex and varied, with a range of clinical presentations. Conducive hearing loss in three dogs associated with the use of ointmentbased otic medications. The point of this snippet is not the reported conducive hear loss after 1–3

weeks treatment with a medication containing gentamicin, betamethasone and clotrimazole in mineral oil hydrocarbon gel. Rather that hearing improved (as measured subjectively by the owners and by BAER testing) after deep flushing. This emphasizes the importance of a deep ear flush to remove residual otic medications in dogs with acute hearing loss after medication. Don’t give up if there is hearing loss; flush out the residual medication.

Selected publications

Burrows, M. Hydrolysate diets: fabulous or folly? Clinical Dermatology Conference, Proceedings Number 423 DD. Centre for Veterinary Education, Sydney University, Australia. 2015 Dawson K. Bartonella henselae in cats: results of a seroprevalence survey and relevance to New Zealand veterinary practitioners. NZVA Companion Animal Society Newsletter, 21(4), 16–18, 2010 Hillier A, Griffin CE. The ACVD task force on canine atopic dermatitis (X): is there a relationship between canine atopic dermatitis and cutaneous adverse food reactions? Veterinary Immunology and Immunopathology 81, 227–31, 2001

Kelly P, Rolain JM, Raoult D. Prevalence of human pathogens in cat and dog fleas in New Zealand. The New Zealand Medical Journal 118, 1226, 2005 Olivry T, Bizikova P. A systematic review of the evidence of reduced allergenicity and clinical benefit of food hydrolysates in dogs with cutaneous adverse food reactions. Veterinary Dermatology 21, 32–41, 2010 Raditic, D; Remillard R, Tater K. ELISA testing for common food antigens in four dry dog foods used in dietary elimination trials. Journal of Animal Physiology and Animal Nutrition 95, 90–97, 2011 Ricci R, Granato A, Vascellari M, Boscarato M, Palagiano C, Andrighetto I, Diez M, Mutinelli F. Identification of undeclared sources of animal origin in canine dry foods used in dietary elimination trials. Journal of Animal Physiology and Animal Nutrition 97 32–38, 2013 Willis-Mahn C, Remillard R, Tater K. ELISA Testing for Soy Antigens in Dry Dog Foods Used in Dietary Elimination Trials. Journal of the American Animal Hospital Association 50, 383–9, 2014 l

CONFERENCE REPORT

41st World Small Animal Veterinary Congress Cartagena, Colombia, September 2016 MIKE SCULLY, BVSc “Should I stay or should I go now”, were my initial thoughts of Cartagena. After landing I saw soldiers every 400 meters from the airport to the Hotel Caribe and once inside the lobby 20 army/police with sniffer dogs and assault rifles. I thought “Is this place safe?” Well yes it was, and as far as Zika virus goes, not one mozzy bite the whole stay despite Contact: mike.scully55@gmail.com, wadestownvet@clear.net.nz

temperature to 34°C. The large military presence was for the peace signing between the government and the FARC rebel group; 250,000 people were killed in this conflict over the last 40–50 years. Despite the signing, the country voted against it in a referendum; however another proposal has been signed between the senate and the FARC. On the first night, before the assembly meeting, there was an informal cocktail party. Many of the delegates were still raving about the Auckland WSAVA Congress, so well done to the organisers; they really made an impact.

The assembly meeting the next day went smoothly. Guatemala wanted to apply for full membership to WSAVA but they didn’t have all the documentation in place and translated. Some said it’s because of the South American ‘mañyana’ (tomorrow) policy. I asked the question “What is the worst thing that could happen if they were accepted today as full members?” After a few extra votes, protocol was changed and they were “in”. Despite the differences between vets our problems are similar to the world over. Venezuela has it tough; they were exempted from paying as it is so hard to get money out of the country.

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

The next day at the Congress there were a lot of streams in Spanish with no translation, however there were plenty of English streams to choose from. The best lecture was by Luke Gamble about a project called Mission Rabies (which WSAVA is involved in). Rabies kills people as well as dogs. ONE CHILD DIES EVERY 10 MINUTES from this disease. The best way to eliminate the disease is to vaccinate dogs along with humane population control. Using this system, with cell phone-based mapping of cases, they have reduced the death rate due to rabies markedly in some areas of Malawi. If the wealthy 1% of the world paid a little more tax this disease could be eliminated in 3 years.

• Trigeminal nerve lesions in dogs. The dog can’t close his mouth so can’t eat. Solution is to lightly bandage mouth for 3 weeks. • Cats with CKD: - Only 25% have phosphate binders has part of their treatment regime. • If urine protein:creatinine ratio is >0.4 then treat (e.g. ACE inhibitor, Semintra) but monitor BP carefully, especially in end stage, as at risk for hypotension.

Conference experiences

The old city of Cartagena was amazing! It was built to keep Sir Francis Drake out. One night we had a meal in a restaurant built in 1503. For the conference dinner, which had a “white” dress code, the whole town square was taken over (see Figure 1). On the final night, there was a beach party with 2,000 people salsa dancing; good times, great memories (and only three kiwi vets there). l

One thing I like about conferences is that moment when a question often at the back of my mind is answered. This time it was that cats with hyperthyroidism may be prone to spontaneous fractures. This happened to me years ago; a cat fractured its humerus while being handled in the clinic, and ironically the owner fractured her humerus several weeks after the cat. Other conference snippets: • In the USA some cancer drugs cost as little as the consumables used in the delivery of the drug. • Hyperthyroid cats: USG is not a useful predictor for azotaemia after radioactive iodine treatment. Cats with low T4 (after treatment) and chronic kidney disease have poorer prognosis than those with normal/ high T4. However another study showed hypothyroid cats survive as long as euthyroid cats as long as they are not azotaemic. • Epileptic dogs being treated with potassium bromide are at risk of seizures after visiting the beach due to salt intake (Royal Veterinary College has an app for seizure control).

Figure 1. (a) A colourful visitor hoping to share breakfast (courtesy of the author). (b) The Plaza de la Aduana ready for the Dinner Party in White (photo courtesy of WSAVA).

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Massey News Buildings

Massey University’s Wildbase Hospital has moved into new premises 10 times larger than the previous space at the University’s Manawatu campus. The new Wildbase building is adjacent to and shares the entrance hall with the small animal hospital. Shell New Zealand chairman Rob Jager officially opened the new building today at a ceremony attended by Massey's new ViceChancellor Professor Jan Thomas, Veterinary Teaching Hospital staff and supporters of Wildbase. Wildbase Hospital is New Zealand's only dedicated wildlife treatment facility, providing medical, surgical and rehabilitation care to hundreds of sick and injured native animals each year. It is also a respected research and teaching institution. For the past 15 years Wildbase has operated from a 25 square metre facility consisting of a basic operating theatre and two small recovery/holding rooms. When it began in 2001 the space was adequate for the 50 birds treated annually, but with patient numbers rising to 327 last year, a new facility was desperately needed.

People

Our newest surgeon, Dr. Wendy Baltzer has arrived and fully integrated into the team. Wendy is a Diplomat of the American College of Veterinary Surgeons and comes to Massey with a wealth of clinical and teaching experience. Most recently senior faculty at Oregon State University, she has a particular interest in orthopaedics and rehabilitation. Wendy’s research interests include the use of free omental grafts to aid fracture healing. She is also keen to form a clinical research group to utilize the recently acquired pressure mat and force plate technologies at the VTH. We hope to be able to generate objective outcome measures to guide orthopaedic interventions. Wendy is currently on maternity leave and is expected back on clinics full time in April. Jonathan Bray has been in the UK for the last four months locuming at the new Fitzpatrick Referrals Soft Tissue/Oncology Centre alongside UK surgeon Nick Bacon. He is

returning to the VTH briefly in May before a permanent move back to Surrey to work in this practice. This hospital is at the leading edge of oncology and suits Jon’s interest in innovative solutions to reconstructive surgery. The VTH has greatly benefited from his leadership and clinical skills over the last several years and he will be a loss to the University and New Zealand, but let’s hope one day he returns to our shores. From April Andrew Worth is taking a year out from Massey to pursue new challenges. He has accepted an initial six-month appointment at the Royal Veterinary College, London. Working alongside seven other surgeons in the soft tissue department, Andrew hopes to gain valuable exposure to the latest developments at the UK’s leading veterinary school. The RVC has over 200 students in each year of the veterinary program, which is rated in the top three worldwide. After the UK he will explore other opportunities in the US or Australia, hopefully including further development of his research interests in lumbosacral disease. Coverage of the surgical service will be in the very competent hands of Wendy Baltzer and Kat Crosse. Helen Milner and Aparna Tikekar are both providing locum coverage whilst a permanent replacement for Jonathan is sought.

Services

Radioactive Iodine Therapy for Hyperthyroidism in Cats

Oncologist Valerie Poirier has re-established a radiotherapy service using I131 for hyperthyroid cats. It has been many years since the VTH has been able to offer this service due to space and licensing limitations. Cases can once again be referred for this life-changing therapy that offers a cure for this common disease. Unlike alternatives that require constant medication or surgical risk, radioiodide therapy can reverse the clinical signs of the disease with minimal risk to the patient. Contact the VTH reception for more information (vethospital@massey.ac.nz). l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Companion Animal Health Foundation Update With 2017 now well underway, it looks to be a year of change and uncertainty. This means there are opportunities for new ideas and growth. CAHF is looking to capitalise on this with the development of a new website underway, new fundraising ideas to help raise our profile and continuing to support NZ-based research to benefit companion animals. CATH WATSON, Chair

Companion Animal Health Foundation

The current trustees of Kate Hill, Boyd Jones, John Munday, Jodi Salinski, Laura Harvey and myself, Cath Watson continue to be committed to furthering the aims of CAHF, with Boyd in particular doing a fantastic job on the fundraising front. The purpose of CAHF is to fund research, projects and education programmes that will ultimately be of benefit to companion animals in New Zealand. Some examples of past projects undertaken by your colleagues in New Zealand include: 1 Examining the effectiveness of the NZVA hip scoring scheme at reducing hip dysplasia (Soo and Worth 2015). The results of this study initiated the change to PennHip 2 Comparing the effects of several analgesic opioids in cat castrations (Kongara et al. 2016) 3 Investigating the epidemiology of leptospirosis infections in dogs in New Zealand (Harland 2015) Recent projects funded include: 1 Investigation of the role of delta toxin from Staphylococcus pseudointermedius in canine dermatitis by Dr Allan Bell 2 The comparison of the diagnostic quality of bone marrow biopsies taken from different sites by Dr Arnon Gal For a more complete list of the research funded, see www.healthypets.org.nz

There is a range of veterinarians benefiting from grants provided by the CAHF; from academics to general practitioners. For example, those who are studying towards Massey University’s MVM qualification would be potential recipients of grants to go towards funding and completing their dissertation projects, with the assistance of an experienced researcher. So, if you feel that you can take advantage of the funds available, and what you have in mind ticks all the qualifying criteria set up by the fund (see www.healthypets.org.nz), then please do not hesitate in contacting us to discuss how we can help. Currently, CAHF funds are slowly growing with payments for completed projects being similar to donations. Regular donations from the Vet Centre Marlborough’s memorial scheme have continued, which are greatly appreciated. Pet Doctors has also given a generous donation in the latter half of 2016. CAV continues its very much appreciated on-going support of $10,000 each year, without which CAHF would have struggled to survive in the very crowded fundraising market of recent times. These donations make it possible to continue funding veterinary related companion animal research in New Zealand, but there is so much more that could be done. The CAHF trustees would like to encourage you all to consider ways in which you, your classmates, or your business can contribute to the fund. Some ideas for you to consider:

1 Memorial scheme – The Vet Centre Marlborough have a wonderful idea for those special pets or clients in their clinic where a donation is made by the clinic on their behalf, and the client will receive a personal thank you from CAHF. 2 Business donation from the sales of certain products or services e.g. Waikiwi Vets makes 6-monthly donations based on the number of euthanasias performed, with a set amount from each euthanasia going towards CAHF 3 Annual donation from you and your fellow Massey classmates 4 Organise a fundraising event through your workplace or classmates 5 A personal donation 6 Client donations: CAHF can provide brochures for clients about CAHF including donation details We greatly appreciate our donors, and would welcome new benefactors so we can apply these funds to furthering the interests of companion animals in New Zealand.

Works cited

Harland A. Epidemiology of Canine Leptospirosis in New Zealand. Master of Veterinary Science Thesis, Massey University 2015 Kongara K, Johnson CB, Sawicki R. Comparative effects of methadone, buprenorphine and morphine on electroencephalographic responses to castration in cats. Journal of Veterinary Anaesthesia and Analgesia. 2016, in press. Soo M, Worth AJ. Canine hip dysplasia: phenotypic scoring and the role of estimated breeding value analysis. New Zealand Veterinary Journal, 63, 69–78, 2015 l

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

2016 Subject Index Title

Author

Issue

Page numbers

ACVS Surgical Summit, 2015 (conference report)

Alastair Coomer

40–41

American Vet Dental Forum, 2015 (conference report)

Angus Fechney

50–52

American Vet Dental Forum, 2015 (conference report)

Geraldine Gorman

39–41

Angiostrongylosis

Boyd Jones

14–17

ANZCVS Science Week, 2016 (conference report)

Pru Galloway

45–49

Atopic disease: proactive management in dogs

Duncan Graham

28–30

Bravecto to treat earmites in puppies

Hannah Bain, Hugh Hasselman

36–38

Brent Higgins (specialist profile)

Toni Anns

40–41

Can the English Bulldog be fixed

CQ Editor

Cerebellar malformation in a puppy

Bernard Vaatstra

26–29

Cerebrospinal fluid collection

Boyd Jones

16–18

Conference report: ACVS Surgical Summit, 2015

Alastair Coomer

40–41

Conference report: American Vet Dental Forum, 2015

Angus Fechney

50–52

Conference report: American Vet Dental Forum, 2015

Geraldine Gorman

39–41

Conference report: ANZCVS Science Week, 2016

Pru Galloway

45–49

Conference report: Vet Orthopedic Society Meeting, 2016

Andrew Worth

42–43

Debbie Simpson (specialist profile)

Hannah Bain

30–32

Diabetes Mellitus management in cats

Boyd Jones

14–24

Diagnosis and staging of chronic kidney disease

Graham Swinney

24–26

Diskospondylitis: case-based review

Philomena Tuohy

26–30

Displacement of protein-bound drugs

Liz Shackleton

24–30

Feline orofacial pain syndrome: case report

Nikki Frost

32–35

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

Title

Author

Issue

Page numbers

Haemotropic mycoplasma infection in cats

Janice Thompson

20–22

Honest placebos

Allan Bell

Hypertrophic cardiomyopathy: treatment with pimobendan

Zoe Kamsma

32–36

In-clinic safety around dogs

Elsa Flint

20–22

Leptospirosis in a South Island dog

Angela Wright

38–43

Osteosarcoma (What is your Diagnosis?)

Brianna Dalbeth

14, 54–56

Parasites of cats and dogs in NZ

Brooke Woollett, Maureen Forsyth, Frederic Beugnet

32–38

Robyn Gear (specialist profile)

Hannah Bain

Specialist Profile: Brent Higgins

Toni Anns

40–41

Specialist Profile: Debbie Simpson

Hannah Bain

30–32

Specialist Profile: Robyn Gear

Hannah Bain

Thyroid neoplasia (What is your diagnosis)

Philip Hyndman

12, 49–51

Tooth resorption in a cat

Geraldine Gorman

20–24

Understanding reviews and consensus statements

Boyd Jones

16–18

Urinothorax (What is your diagnosis?)

Philip Hyndman

12, 44–45

Urolithaiasis in a guinea pig (What is your diagnosis?)

Brendon Bullen

14, 46–47

Vet Orthopedic Society Meeting 2016 (conference report)

Andrew Worth

42–43

What is your diagnosis? Osteosarcoma

Brianna Dalbeth

14, 54–56

What is your diagnosis? Thyroid neoplasia

Philip Hyndman

12, 49–51

What is your diagnosis? Urinothorax

Philip Hyndman

12, 44–45

What is your diagnosis? Urolithaiasis in a guinea pig

Brendon Bullen

14, 46–47

Companion Quarterly: Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA | Volume 28 No 1 | March 2017

COMPANION QUARTERLY â&#x20AC;&#x201C; Official Newsletter of the Companion Animal Veterinarians Branch of the NZVA

Companion Quarterly

OFFICIAL NEWSLETTER OF THE COMPANION ANIMAL VETERINARIANS BRANCH OF THE NZVA Volume 28, No. 1 | March 2017

VOLUME 28 NO 1 MARCH 2017

Managing ureteral obstruction

Malocclusions

Guidelines for managing feline hyperthyroidism

Recurrent coxofemoral joint luxation

Challenges and pitfalls of diabetes mellitus