CAS Newsletter Vol27 no1 March 2016 by Companion Quarterly

NZVA COMPANION ANIMAL SOCIETY NEWSLETTER

New Zealand Veterinary Association

Companion Animal Society Volume 27 No 1 March 2016

In This Issue ...

• Management of diabetes mellitus in cats • Diskospondylitis – a casebased review • Parasites in NZ cats and dogs - a survey • Conference report: American Veterinary Dental Forum 2015 • Specialist Profile: Robyn Gear • NZVJ Companion Animal Digest • What is your diagnosis?

VOLUME 27 NO 1 MARCH 2016

Newsletter

Volume 27 No. 1 March 2016 ISSN No. 1173-6941

EXECUTIVE COMMITTEE 2016 President

Contents

Brendon Bullen

Editorial......................................................................................2

brendonbullen@gmail.com

Secretary

From your society.......................................................................4

Rochelle Ferguson rochellemf@hotmail.com

Grants & scholarships................................................................6

Treasurer

Aimee Brooker

Article winners...........................................................................8

ollyaimee@gmail.com

Committee Members

AGM 2016 Call for Nominations................................................10

helenbnz@gmail.com

What is your diagnosis..............................................................12

Helen Beattie Hannah Bain

Philip S. Hyndman

hannah.bain@merck.com

Warren Stroud

Practical management of diabetes mellitus in cats....................14

stroud@wellpet.co.nz

Boyd R Jones

John Munday

j.munday@massey.ac.nz

Diskospondylitis – A case-based review...................................26

Catherine Watson

cath@vetservices.co.nz

Philomena Tuohy

Pauline Calvert

pauline.calvert@merck.com

Survey of fleas, ticks and gastrointestinal helminths in cats and dogs in New Zealand.............................................32

EDITORAL COMMITTEE Sarah Fowler (Editor) Genevieve Rogerson Angus Fechney Craig Irving Christine Moloney (Advertising) Janice Thompson Simon Clark

Brooke Woollett, Maureen Forsyth, Frederic Beugnet

Conference Report: 29th American Veterinary Dental Forum 2015.....39 Geraldine Gorman

CAS Specialist Profile – Robyn Gear.........................................42

Address for submitting copy/ correspondence etc.

NZVJ: Companion Animal Digest Volume 64, Issue 2, 2016...... 43

Sarah Fowler

What is your diagnosis: The answer......................................... 44

66 Callum Brae Drive Rototuna Hamilton 3210 Ph H:(07) 845-7455 Mob: 027-358-4674 Email: sarah.fowler@gmail.com

Massey Home Page................................................................. 46 Subject Index: Volume 26: 2015................................................47

Advertising Manager Christine Moloney

25 Manchester St, Feilding Telephone: 06 323 6161 Fax: 06 323 6179 Email: christine.moloney@totallyvets.co.nz

Cover Photograph

http://www.nzva.org.nz

Brock the Border Collie who belongs to Catherine Bryant of Auckland. Photo by Catherine Bryant

CAS Website

Cover Design & Newsletter Setting

NZVA Website

http://cas.nzva.org.nz

The whole of the content of the CAS Newsletter is copyright, CAS/New Zealand Veterinary Association Inc.

Penny May Email: penfriend@xtra.co.nz

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

Disclaimer: The CAS newsletter is a non peer reviewed publication. It is published by the Companion Animal Society (CAS), 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 CAS newsletter, the CAS executive, the NZVA, and neither CAS nor the editor endorses any products or services advertised. CAS 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 CAS 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 CAS, 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.

March 2016

Companion Animal Society Newsletter

Editorial 2015 ended up on a high note for the

climate, with the members of the United Nations signing The Paris Agreement. This agreement set a goal to limit Earth’s warming to 2°C above pre-industrial levels, and to strive for limiting it to a 1.5°C increase. Without this agreement, the world was on track to 4°C+ of warming, a situation that would not support human civilisation as we know it, or potentially not at all. However, the world’s government’s current pledges as part of the Paris Agreement will only hold warming to between 2.7°C and 3°C above pre-industrial levels, and whether governments will reach these pledges is not definite. Citizens and companies will have to step in as well as governments, to do their part for the climate. There are a number of factors that veterinary clinics can look at to reduce their carbon footprint. This is not just about helping with this ‘tragedy of the commons’ that the planet is currently facing. There is a growing, solid business case to move towards sustainable business practices; in many cases they are becoming cheaper than the standard way of doing business. Approximately 80% of electricity in NZ is generated from renewable sources. While this is a high number, this still leaves 20% of NZ’s electricity derived from fossil fuels. Solar panels have roughly halved in price over the last 2 years, with payback periods for capital investment continuing to fall. They also protect against future increases in power costs. As long as there is sufficient roof space, solar is an excellent choice for veterinary clinics, as they operate mostly during the day, when electricity production from solar is at its highest. It is possible to either remain connected to the national grid, drawing additional power as required, use batteries to store any excess power, or a combination of both. Good old-fashioned 2

power usage reduction can also be achieved from small changes. For example, LED and compact fluorescent lighting is continually improving in quality and reducing in price. NZ’s electricity all goes into a single pot when it reaches the national grid, so it is not possible to determine whether electricity being used is coming from a renewable source or not. However it is possible to support NZ’s renewable investment as much as possible while remaining on the national grid, by purchasing electricity directly from generator/retailer power companies that solely use or prioritise renewable electricity production. Unfortunately widespread electric vehicle usage is still likely to be years away in NZ, unlike early adopter countries such as Norway where in 2015, a quarter of new cars sold were electric. For clinics that do have staff vehicles, taking fuel usage into account when making vehicle decisions can be a way to lower their carbon footprint and save money on fuel costs. I have seen several clinics in the UK that are subsidising public transport costs, and active transport modes such as cycling for their employees. While this is not going to be possible in many areas of NZ, for these clinics, it was a way to free up clinic parking space for clients, and generate goodwill from staff. Wellington regional council encourages active and public transport to work through its active a2b programme (www.activea2b.org.nz). Consumers are becoming more discerning when it comes to sustainable business practices. While perhaps unlikely to generate a lot of new clients, for many people, knowing that their vet clinic takes sustainability concerns seriously, will make them feel better about where they take their pets. Brendon Bullen CAS President

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From your society Summary of minutes

Meeting held 4 November 2015 at NZVA Boardroom in Wellington The start was delayed due to weather related flight disruptions Attendance: Catherine Watson, Rochelle Ferguson, Helen Beattie, Brendon Bullen, Hannah Bain, and Sarah Fowler. Apologies: John Munday, Pauline Calvert, Warren Stroud. Matters arising from previous minutes and correspondence: Euthanasia policy to be completed by 1 December and further work to do on the renal policy early in the New Year. EVBF has requested funding from branches – further detail on how this would be used is to be requested. President’s report – Brendon Bullen: Summary of media reports and meetings held including the Veterinary Wellness project group regarding updating the mentor scheme and MPI regarding cat and dog export requirements. Treasurer’s report – Taken as read. Guest: Julie Hood (NZVA CEO) and Caroline Robertson (NZVA President): Julie presented her speech to the Australasians Association Meeting – How you think matters. This related to looking at the professions defining characteristics and seeing where our competitive advantage is. It was noted that members want tangible results and CR was interested in looking at why we are paid lowly, why we aren’t valued, and why physiotherapists supported more highly than veterinarians by the government. They have invited CAS to provide feedback on what is the one thing, which if we did it, would make us feel really engaged? And how we might be able to help with planning for next year. Guest: Helen Beban and Janet Eden (VCNZ) – Topics discussed included treating exotic species, defined informed consent, providing veterinary services at cat shows, controlled drug management, euthanasia when vet believes it is required and owners don’t agree, Section 29 drugs, compulsory CPD recording, changes to the COPC and minimum practising standards.

Guest: Frazer Allan – Frazer gave us a view of companion animal practice from the “other side”. Topics included supporting new graduates in practice, how to utilise the skill set they bring – particularly as digital natives and their ability to connect with subsets of clients not traditionally reached. The discussion also touched on how the NZVA could give value to Massey clinicians, the changing business scape with an increase in corporate practices and disruptive technologies such as teleradiology. Guests: NZVA – Peter Benestead, Brent Mudgeway, Sara Passmore Callum Irvine, Leanne Fecser and Shannon Leader. We discussed continuing education, the veterinary refresher scheme, member communications, AMR, and activity that NZVA can do to support the NAWAC. Newsletter Editor’s report – Sarah Fowler: Discussion around CAS newsletter and plans were made to give it a refresh, along with formatting it to an optional digital version. CAHF and CAS grants update: Chris Hutchings has resigned. Plans made to approach Boyd Jones to chair the Trust. Interest shown in the idea to look at driving the direction of research supported by CAHF rather than passively supporting projects as they come along. NZCAC: The new structure for the NZCAC is now in place. Veterinary Refresher Scheme: Decision made to continue the scheme in 2016 in the same format as it was delivered in 2015 where all modules were available to do at participants own pace with a general format moderated by a CAS committee member. AMR Update: Decision made to adopt FECAVA guidelines on antimicrobial use, in the absence of more specific NZ based guidelines. Next meeting 24/25 February at NZVA, Wellington

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Companion Animal Society Newsletter

NZVA CAS members are encouraged to apply for these Grants and Scholarships:

The New Zealand Veterinary Association Companion Animal Society

Hill’s Pet Nutrition/CAS Educating the Educators Scholarship This scholarship provides assistance for veterinary educators to attend advanced level continuing education events outside New Zealand. We recognise the importance in supporting our leading veterinarians’ participation in international conferences to ensure they remain up to date. With the terms of the scholarship we also encourage the dissemination of this knowledge to the wider CAS membership through articles in the CAS Newsletter and presentations to regional branches. This scholarship is open to both CAS members and non-members – with CAS members being more generously supported. Applications are considered at the end of March and September each year but can also be made on a case by case basis. The scholarship provides $10,000 per annum to be divided between applicants. We are very grateful to Hill’s Pet Nutrition as the principle sponsor along with support from Massey University Institute of Veterinary, Animal and Biomedical Sciences and VetLearn. Please email the CAS Secretary Rochelle Ferguson cas@vets.org.nz for more information or see our website. Thanks to Hill’s Pet Nutrition for their ongoing support

CAS/CAHF Annual Project Grant 2016 Sponsored by Virbac The Companion Animal Health Foundation (CAHF) is a charitable trust established by the Companion Animal Society to fund research projects that will enhance companion animal health and welfare. The CAHF website has a list of the projects that have been supported by the CAHF and details of the papers published following this research. Applications are invited from CAS members each March and September for funding towards research projects that meet the aims and objectives of the CAHF. Application details along with the terms and conditions are also available from the website or by contacting the CAS Secretary Rochelle Ferguson on cas@vets.org.nz

CAS presents: “A week with...” We would like to support a CAS member to upgrade their skills in an area of interest and have enlisted the support of five specialists who have offered to host a CAS member for a week. Applications are invited from practitioners with over 3 years’ experience who would be interested in spending a week with one of the following specialists: • Dr Andrew Worth, BVsc, MANZCVS (Radiology), PGDipVCS, FANZCVS to see orthopaedic surgery at Massey University Teaching Hospital in Palmerston North. • Dr Pru Galloway, BVSc (dist), MANZCVS, FANZCVS (feline medicine), to see feline medical referrals at Catmed Lower Hutt in Wellington. • Dr Warrick Bruce, BVSc(Dist), MVM, DSAS(ortho), CertSAO, MANZCVS, to see orthopaedic surgery at Vet SOS in Hamilton. • Dr Alastair Coomer, BVSc, MS, Diplomate. ACVS, to see small animal referral surgery at the Veterinary Specialist Group in Auckland. • Dr John Munday, BVSc, PhD, Diplomate ACVP to find out what the real diagnosis was in the pathology department at Massey University in Palmerston North. This is a chance to tailor a CPD course to your own specific interest at a time that suits you best. The grant is for $2000 and covers your time away from practice and travel costs. To benefit all CAS members, as a condition of the grant, we request that you share your experience by writing a report about your time seeing practice and an article based on a topic of interest for the CAS newsletter. Further information and application forms available from the CAS Veterinary Resource Manager cas@vets.org.nz Applications close on 31 March 2016.

Companion Animal Society Newsletter

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Companion Animal Society Newsletter

EYEVET Services Limited

Article of the Issue Winner Katherine Reid December 2015, Volume 26(4), p 18

Paper: “Anxiety and pain in companion animals in the clinic.”

EYEVET Services Limited

Article of the Year Winner Tania Krupitza

2015, March, Volume 26(1), p 20 Paper: “Management of a cat with traumatic brain injury.”

Winner of the Undergraduate Student Article 2015 Katherine Reid December 2015, Volume 26(4), p 18

Paper: “Anxiety and pain in companion animals in the clinic.”

Companion Animal Society Newsletter

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Companion Animal Society Newsletter

AGM 2016

Call for Nominations Nominations are called from CAS members interested in serving on the branch committee. All CAS members are eligible and welcome to apply. The term of office for committee members is a minimum of 2 years and a maximum of 3 years. Three positions are available this year – Brendon Bullen and Helen Beattie have both served a three-year term and Rochelle Ferguson resigned to take up the CAS Veterinary Resource Manager role. Brendon Bullen and Helen Beattie have both indicated that they are available for re-election. The 2016 AGM will be held in June, in association with the NZVA World in Fusion Conference in Hamilton 21–24 June 2016. Time and venue to be advised by email in April. Signed nomination forms from a proposer, seconder and containing a declaration from the nominee that he/she is prepared to stand for election must be lodged with the Branch Secretary no later than 23 April 2016. Nomination forms and further information about serving on the committee is available from our Veterinary Resource Manager, Rochelle Ferguson at cas@vets.org.nz.

What is your diagnosis? The Companion Animal Society publishes a regular feature in which an interesting companion animal case is presented to readers. The initial page presents the case history, signalment and initial diagnostic results (physical exam findings, radiographs, ultrasound images, bloodwork etc). Questions are then posed to challenge readers understanding of the case, for example: • What is your list of differential diagnoses? • How would you confirm which is correct? • What treatment options are available? • What other factors must be considered? On a later page the questions are answered and the remainder of the case report revealed (e.g. conclusive diagnosis, treatment or treatment options, outcome). We invite submission of articles following this format from any interested veterinarian (or student). For each case accepted for publication there is a payment of $150 sponsored by MSD Animal Health. The deadlines for submission are the 25th of January, April, July and October, 2015. Please see the Instructions for authors in the December issue of the CAS Newsletter or available from the Editor. Make sure you include your name, qualifications, title and contact details.

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Companion Animal Society Newsletter

What is your diagnosis? Philip S. Hyndman BVSc, Zoetis Companion Animal Rotating Intern. Massey University Veterinary Teaching Hospital

A 7-month-old female spayed domestic shorthair cat was presented to VetEnt in Havelock North with a history of being missing for a few days. When she returned home the owner noted a quiet demeanor in a normally fiesty cat and mild inappetance. On clinical examination this patient had a sluggish skin tent, tacky mucous membranes, was painful on palpation around the hindend, tender on abdominal palpation and had shredding of her claws on all four feet. As the referring veterinarian was concerned that this patient had been involved in a traumatic accident radiographs were performed. On these radiographs no significant fractures of the hindlimb long bones were identified and the diaphragm appeared intact. The outline of the bladder wall was not visible despite relatively good serosal detail. A ventrally localised loss of detail was noted within the thoracic cavity with soft tissue opacity reducing the visibility of the ventral cardiac silhouette. Intravenous fluid therapy and pain relief were administered with stabilisation and monitoring at VetEnt Havelock North overnight. The following day clinical examination revealed increased respiration rate (66 bpm) with moderate respiratory effort. No urination had occurred since presentation and the cat’s abdomen was distended with a fluidy feel when palpated. Radiographs were repeated with the lateral view shown below in Figure 1. Following radiographic examination, abdominocentesis was performed and watery blood tinged fluid obtained. Due to the clinical deterioration and a high suspicion of bladder rupture, this case was referred to Massey University Veterinary teaching hospital for surgical management. What abnormalities can you identify in the radiograph? What are your differential diagnosis for your radiographic findings? What further testing could you perform?

Figure 1.

Left lateral radiographic view (“catogram”) supplied by Dr Alanda Rafferty VetEnt Havelock North

(Answer on Page 44) Contact Email: P.Hyndman@massey.ac.nz

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Companion Animal Society Newsletter

Practical management of diabetes mellitus in cats Boyd R Jones BVSc, FACVSc, DECVIM-Ca, Emeritus Professor Diabetes mellitus is common and increasing in prevalence. We have all managed clinical cases and developed protocols that work for us. We are victims of our own experience and despite our developing confidence some cats just don’t read the text books. Each patient is an individual and each cat has an owner who may or may not have some knowledge and understanding of diabetes. If they do, they may be able to take an active role in management of their cat’s diabetes. The diagnosis of diabetes mellitus is the easy part. Optimal management can be a problem. Feeding an appropriate diet, weight management and selection of an appropriate insulin type are all important in obtaining glycaemic control, and in reversing glucose toxicity which may provide diabetes reversal in some patients. Monitoring a variety of laboratory parameters is important in assessing the response to insulin and determining adjustments to the dose rate and frequency of administration. In March 2015 The International Society of Feline Medicine published consensus guidelines on the management of diabetes mellitus in cats (Sparkes et al. 2015). The consensus statements are based on a review of existing literature and take into account the quality of the published studies. The panel acknowledges that in some areas data are lacking and further studies are required. The contributors to the guidelines were academics and specialist feline clinicians. The reader should recognise that these are consensus guidelines and are not intended to be a complete review of all aspects of diabetes in cats. I have summarised key parts of this paper and commented where appropriate (italics).

Epidemiology and pathogenesis Type 1 diabetes is rare in cats.

Diagnosis

Classical clinical signs of diabetes mellitus include polydipsia, polyuria, weight loss, lethargy and polyphagia. Plantigrade stance, weakness, depression and anorexia occur less commonly. Confirmation is made by identifying persistent hyperglycaemia and glucosuria. Stress hyperglycaemia must be excluded. Stress seldom elevates the blood glucose to ≥16 mmol/L and frequently resolves in a few hours. Repeat measurement and/or home monitoring will establish persistent hyperglycaemia. Concentration of serum fructosamine, which is indicative of the blood glucose during the preceding week, is not affected by short term stress. Its measurement can be helpful in confirming a diagnosis of diabetes mellitus and in monitoring glycaemic control. Evaluation of the diabetic cat The panel recommended the following should be included: • Complete history and physical examination • Serum biochemistry • Urinalysis: ideally with culture if there is an active urinary sediment The following would ideally be included: • Complete blood count • Serum fructosamine • Serum thyroxine in older cats to exclude hyperthyroidism The panel recognised the high prevalence of concurrent diseases in older cats, including pancreatitis. Ultrasonography and measurement of pancreatic lipase maybe indicated. The panel rightly emphasises that the interpretation of these test results may not be straightforward.

The disease in most cats has similarities to human Type 2 diabetes mellitus resulting from cell dysfunction and insulin resistance. The major risk factors are: - Obesity: obese cats are up to 4 times more likely to develop diabetes mellitus than optimal-weight cats - Increasing age - Breed: Burmese cats have been reported to have a higher risk in studies from Australasia and Europe - Physical inactivity - Gender: male and neutered cats are at greater risk - Drug treatment: glucocorticoids and progestogens may result in insulin resistance and predispose to diabetes mellitus

Diabetic ketoacidosis (DKA) develops in a proportion of diabetic cats. This is confirmed by high blood or urine ketones. It is essential to confirm or eliminate concurrent diseases or confirm DKA. The presence of other diseases or DKA will probably alter the outcome of treatment.

If the factors contributing to insulin resistance can be reduced and β-cell function improved, diabetic remission can be achieved and exogenous insulin therapy may no longer be needed. Remission may be temporary only (we have all had cases that fit this scenario).

The panel agreed that achieving both goals can be difficult but avoiding hypoglycaemic episodes (for most owners) was paramount and should be the priority. Safe and effective glycaemic control can be achieved with good home monitoring by owners. The panel emphasised that dealing with hypoglycaemic episodes was significant for most owners (Table 1).

Goals in managing diabetic cats

The main goals of management are twofold: • To limit or eliminate the cat’s clinical signs using a treatment regimen that fits the owner’s daily routine whilst avoiding insulin-induced hypoglycaemia and preventing other complications (e.g. DKA)

Massey University, Palmerston North

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Hypoglycaemia was defined as a blood glucose <3.0–3.5 mmol/L. Mild hypoglycaemia can be tolerated by the cat and be unnoticed by the owner. Severe hypoglycaemia is life threatening. Maintaining a blood glucose below the renal threshold in most cats avoids osmotic diuresis and may reduce the risk of glucose toxicity. Good exogenous insulin control of hyperglycaemia may increase the β-cells’ capacity to regain insulin secreting ability and ameliorate the effects of glucose toxicity. Remission of diabetes can occur in a proportion of treated cats when they are under better glycaemic control. Minimising the negative impact of diabetes mellitus on the owner is important, in order to maintain their compliance and avoid euthanasia of the cat. The veterinarian can amend treatment protocols to reduce such owner concerns (Table 1). Table 1.

Owner considerations Owner concerns

Difficulties in boarding

Vet’s response Simplification of treatment

Difficulties leaving the cat with friends or family Adapting social life and work to the disease Worries about costs Wanting more control of the diabetes General worry about the diabetes Worry about possible hypoglycaemia

Use of home monitoring of blood glucose (HMBG) Avoid tight glucose regulation and /or increase home monitoring

Role of diet

Body weight and body condition should be monitored regularly (every 1–2 weeks). Calorie restriction to promote weight loss is essential to improve glycaemic control. Feeding exclusively wet foods is preferred as calorie intake is reduced and water intake increased. Close monitoring of the blood glucose was recommended during any weight loss programme. The optimum diet A restricted carbohydrate (≤ 12% metabolisable energy or 3g /1000 Kcal) diet was recommended. Wet and dry foods formulated for diabetes are low in carbohydrate. The panel notes that good control can be achieved with insulin therapy and higher carbohydrate diets. (There may be other health reasons why a low carbohydrate diet may not be indicated.) Feeding The optimum feeding regimen for cats with diabetes mellitus has been poorly investigated. In practice post prandial changes in blood glucose maybe unpredictable therefore some clinicians prefer to feed the cat at the same time as insulin is administered. For owners too, injecting the cat while it is eating is easier. Frequency of feeding is not critical but establishing a daily routine is important for an individual cat. If food is withheld for any reason (e.g. anaesthesia) it is safe to administer 50% of the usual insulin dose and then monitor the blood glucose.

Oral hypoglycaemics

There is no good evidence to support their use in preference to insulin therapy in cats. The review by Palin and Feldman (2013) summarises their use in cats. Oral hypoglycaemics are an option if owners refuse

insulin therapy. Glipizide is the one agent with some supportive evidence for its efficacy.

Which insulin?

There are many formulations available which can be used to manage diabetes mellitus safely and effectively especially when combined with an appropriate diet. The choice depends on availability, familiarity with using it and, in some countries, regulatory legislation. The available insulin preparations fall into three main groups (Table 2). The panel emphasised that there is individual variation between cats and between insulin types – in individual cats and in different formulations of the same type of insulin. Insulin glargine and insulin detemir have an activity over 24 hours but some studies show a true clinical duration of activity close to 10–16 hours. Insulin glargine and insulin detemir and PZI last longer in cats than lente insulin and are likely to provide better control when used twice daily. Longer acting insulin may produce a more gradual decline in blood glucose. Table 2.

Insulin types and properties in cats

Type

Example

Typical peak activity (glucose nadir)

Typical duration of effect

Medium acting insulins - Lente - Insulin zinc suspension

Caninsulin (Merck / MSD)

2–8 h post injection

8–10 h

ProZinc (Boehringer Ingelheim)

2–6 h post injection

13–24 h (few studies with ProZinc)

12–14 h post injection

12– >24 h

Longer acting insulins - protamine zinc insulin (PZI)

Longer acting insulin analogues - insulin glargine - insulin detemir

Lantus (Sanofi) Levemir (Novo Nordisk)

Recommendations for insulin preparations and frequency of dosing

The panel recommended that whenever possible the use of longer acting insulin preparations (e.g. glargine, detemir or PZI) 12-hourly was best for optimum control. The panel supported a 12-hourly injection schedule but agreed that many owners could not achieve this schedule. 12 hours ± 2 provided flexibility, or an insulin injection could occasionally be omitted if work, family or social commitments precluded injection at the correct time. The primary goal is to minimise clinical signs with the more specific aims of: - controlling the blood glucose to < 14 mmol/L in any 24 hours (< 11 mmol/L provides better diabetes remission) - avoiding clinically significant hypoglycaemia at all times. If twice daily administration of insulin is proving difficult in obtaining control, more frequent administration or a change of insulin type was recommended. The panel emphasised that the insulin concentration (40 iu/ml or 100 iu/ml) must be appropriate for the dose administered whether from pens or multidose vials. The dose of insulin for most diabetic cats

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is small. Insulin of 40 iu/ml with an appropriately calibrated low dose insulin syringe is most helpful. DO NOT dilute insulin to facilitate dosing. Owners find an insulin pen easier to use and there is one insulin pen (Vetpen: Merck/MSD Animal Health) specifically for veterinary use. The panel emphasised care with insulin vials with regard to storage (refrigeration 3–6 months), and repeated needle puncture (potential contamination). Deviation from the manufacturers’ recommendations must be undertaken cautiously.

Initial management of the diabetic cat

The starting dose of an intermediate or longer acting insulin in a non-ketotic cat: - 0.25–0.5 iu/kg q 12h (rounded down to nearest unit, generally ≤ 2 iu/cat q 12h) - The higher dose 0.5 iu/kg is justified if the blood glucose is > 20 mmol/L - Obese and overweight cats should be dosed according to their estimated weight if they were not obese. - Because hyperglycaemia itself causes insulin resistance and β-cell dysfunction, successful treatment may reduce insulin requirements (this is important!) Dose of insulin is increased if clinical signs persist and blood glucose is elevated (clinic or home measurement 5–7 days after starting treatment). Do not increase the dose more frequently than every 3–7 days. This is important to prevent hypoglycaemia, rebound hyperglycaemia and poor control. Whether the first days of treatment are conducted at home or in-clinic is an owner/veterinarian decision. Some owners/vets prefer in-clinic to assess the initial response to insulin, but stabilisation will not occur in the first days. In preparation for discharge the owner must be educated in the technical aspects of treating a diabetic cat. There should be detailed instruction and demonstration regarding: • optimal diet and feeding • use of insulin syringe and/or pens • correct handling and storage of insulin and the injectors • clinical signs of hypoglycaemia and how to treat if it occurs Written instructions are important and web-based resources are also available (use them, they are very helpful).

Home (outpatient) stabilisation of the diabetic cat Five to ten days post-discharge • The cat should be re-examined in the clinic, either after it has received food and insulin at home, or before the insulin dose is administered if the cat eats well when hospitalised. • A thorough physical examination should be performed, the history of clinical response at home should be reviewed – including home records of daily water intake, urine glucose testing etc – and laboratory parameters re-evaluated as needed. • A blood glucose curve (BGC) should be performed where possible. Ideally, blood glucose is measured

every 1–2 hours (for lente insulin) or every 2–3 hours (for longer acting preparations) for at least 12 hours. Remember that blood glucose can vary from day to day within individuals. • As cats are prone to stress hyperglycaemia, the accuracy of data generated from in-hospital curves may be questionable. Serum fructosamine measurement and/or the use of home monitoring of blood glucose (see later) can, therefore, be helpful. • Some clinics use a continuous glucose monitoring (CGM) system to evaluate the response to insulin; this can reduce the risk of stress hyperglycaemia induced by repeated sampling for blood glucose, allow detection of brief periods of hypoglycaemia and facilitate overnight blood glucose monitoring. CGM systems can also be used in the home, but owners must be able to take blood from the cat for calibration of the machine. The dorsal neck may be the most appropriate site for sensor placement. • Insulin adjustments are made according to results of clinical monitoring, blood glucose concentrations and clinical signs (Table 3). Table 3.

Blood glucose (BG) concentrations and possible alterations in insulin after first 5–10 days of therapy

Blood glucose

Action

Nadir BG <4.5 mmol/L

- Reduce insulin dose by 50% - Consider longer acting insulin if peak BG >14 mmol/L

BG 4.5–14 mmol/L on all samples measured throughout the day

Maintain therapy

Peak BG >14 mmol/L and nadir BG 4.5–8 mmol/L

- Maintain therapy and retest after 1–2 weeks; or - Change insulin (if using lente) to a longer acting insulin; or - Increase dose by 0.5 iu/cat q 12h (depending on peak and nadir BG)

Peak BG >14 mmol/L and nadir BG Increase dose by 0.5–1.0 iu/cat q 12 h >8.0 mmol/L with signs of ongoing hyperglycaemia

Three weeks post discharge The cat is re-evaluated as above, with a BGC performed at home or in the clinic. Home monitoring of blood glucose should, where possible and appropriate, be discussed with the owner and support material provided. Home monitoring of blood glucose The panel encouraged the use of home monitoring, as this helps provide more control over the disease, aids in the identification of hypoglycaemia and may provide better glycaemic control. Although not all owners are able to perform home monitoring, it can be successfully undertaken by most, with sufficient support, and ideally should be introduced early in the management of diabetes. Assistance (by the veterinarian or veterinary nurse) should be readily available for owners. An experienced nurse or veterinarian should teach capillary or marginal ear vein blood sampling using a lancing device and a portable glucose meter validated for use in cats, during an extended consultation. Blood may be obtained interchangeably from the pinnae and metacarpal or metatarsal pads, a procedure that is well tolerated by most cats. (Printed and web-based resources should be made available to owners.) A home BGC can be obtained by measuring blood glucose before the morning insulin injection, and every

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2–3 hours for 12 hours (or hourly if hypoglycaemia is suspected). However, owners must be counselled not to make decisions regarding insulin dosage without prior discussion with the veterinarian.

samples are recommended. An ideal BGC has the shape of a shallow bowl. The highest value should not exceed 14 mmol/L and the lowest not less than 4.5 mmol/L.

(Remember, poor management decisions and mistakes are made because of inadequate monitoring for THAT patient.)

Remember stress can have an effect on blood glucose concentrations and may lead to the erroneous assumption that a diabetic cat is poorly controlled. Home monitoring is the preferred method to evaluate glycaemic control.

Intensive management of feline diabetes mellitus

Intensive management of diabetes has been described, using regular home monitoring of blood glucose (generally at least 3, and on average 5, blood glucose samples daily) and appropriate adjustments of insulin, with the aim of maintaining tighter control of blood glucose concentrations thus keeping it closer to the physiological range. There is some evidence from two small studies using twice daily glargine injections in diabetic cats that tighter control may be more likely to result in remission of diabetes. There is also some evidence that the longer acting insulin analogues (glargine and detemir) may be less likely to produce clinical hypoglycaemia when tighter control is aimed for, although good comparative studies are lacking. Studies involving intensive management of diabetes have often recommended aiming for a blood glucose concentration between a low of 2.8–3 mmol/L and a high of 5.5–11.1 mmol/L throughout a 24-hour period. The panel believed that undertaking multiple daily blood glucose measurements and aggressive, tight control of BG was unrealistic for most owners. Intensive monitoring of BG may allow lower peak BG concentrations (<11 mmol/L) but there was no evidence (no randomised control data) of a clear clinical benefit. Aiming for a nadir of <4.5 mmol/L should be avoided.

Glucose meters

A meter validated for feline use should be used (e.g. AlphTRAK2 – Abbott Animal Health). Meters designed for humans frequently give falsely low results for cats (or high!) but the differences may be acceptable for clinical use.

The use of blood glucose curves

The blood glucose nadir, duration of insulin effect and the pre-insulin blood glucose are the most important parameters on which to base adjustments to the insulin dose. BGCs can provide these data but they have limitations and there is often day-to-day variation in cats with poor glycaemic control. Compared with home BGCs, in clinic BCGs may over or underestimate glycaemic control which can reflect daily variation or the influence of stress, possible variation in food intake and/or variations in insulin dose. The panel warned that BGCs should be interpreted with caution and in light of the clinical data. The initial BGC should be used to detect hypoglycaemia rather than to fine tune therapy for diabetes. It may not be necessary to complete a full BGC on each measurement. Taking blood samples every 2–3 hours (for longer acting insulin) is usually adequate but if hypoglycaemia is suspected, hourly

Long-term management of the diabetic cat Monitoring at home The panel recognised the value of owner-obtained information. Owners should be encouraged to keep a diary and record: - The cat’s overall wellbeing – demeanour/activity - Daily water intake – the reduction in water intake is a good marker of insulin response. The type of diet affects water intake. Assessment can be subjective or measured accurately (e.g. a measuring jug) - Daily urine production – subjective or measured - Daily feeding – type and amount eaten - Daily insulin administration – time and dose - Weekly body weight and body condition score - Urine glucose – especially if owners are unable to perform home blood glucose testing. Owners should be advised not to alter the insulin dose based on their results without discussion with a veterinarian. Persistent glucosuria suggests inadequate control (ketones also) - Blood glucose – where good home glucose monitoring is possible. Record results. Ideally weekly until stable then 3–4-weekly. - Spot checks if concerned - Less frequent (2–6-weekly) if home monitoring is not easy. - Blood glucose measurement prior to insulin dosing as frequently as practical Some or all of these measures may be useful for owners who find performing repeat blood glucose measurement difficult or stressful. If blood glucose is measured prior to insulin dosing, insulin can be withheld or a lower dose administered whenever a low reading is obtained, thus helping to avoid hypoglycaemia. Again, owners must be advised not to adjust insulin dosage without discussion with their veterinarian. ‘In clinic’ monitoring Frequent re-evaluations are required initially to slowly titrate the insulin dose, to detect diabetic remission and to identify difficult-to-stabilise cats that require further work-up. The frequency of clinic visits will depend mainly on the response to treatment and the owner’s ability to monitor blood glucose at home. For in-clinic monitoring a guide would be assessment at 1, 2–3, 6–8, 10–12 and 14–16 weeks after initiating treatment. The frequency of clinic re-examinations can then generally be reduced to approximately every 1–4 months depending on how stable the cat is and the conscientiousness/ability of the owner to undertake home monitoring. If diabetic remission seems likely, more frequent checks maybe appropriate.

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March 2016

Companion Animal Society Newsletter

Each re-evaluation will vary according to clinical needs but may include: • Owner diary (see above) • Body weight and body condition • Physical examination • In-clinic BGC (e.g. after the owner first gives insulin and food at home) may be desirable if home glucose measurement is not regularly performed. • Measurement of serum fructosamine (q.v.)

Adjusting insulin therapy

Clinical signs and blood glucose measurements (at home or in-clinic) are the most important parameters on which to base adjustments in insulin dose. If clinical signs such as PU/PD have resolved and the body weight is stable, cats are usually well controlled (although some may also be overdosed). Conversely, persistent clinical signs and weight loss suggest poor glycaemic control and/or concomitant disease. If there is a discrepancy between clinical signs and results of a BGC, treatment decisions should err on the side of caution – fructosamine concentrations should be re-evaluated, and a BGC repeated after a few days before any treatment decision is taken. During the first 3–4 months of therapy the veterinarian should interpret BGCs and make decisions on treatment adjustments (Table 4). With adjustment of insulin doses it is also valuable to assess the full BGC. The shape of the curve and timing of nadirs may vary between cats. This information may affect decisions on dose adjustment, the aim being to keep blood glucose between a maximum of 10–14 mmol/L and a minimum of 4.5–8 mmol/L. With glargine and detemir for example, in some cats the glucose nadir may occur at the time of insulin dosing. During long-term management, owners may gain sufficient experience with support, to make slight insulin adjustments on their own, but according to written guidelines. Dose adjustments should be made no more often than every 5–7 days (with hypoglycaemia as the exception) to allow time for equilibration to a new insulin dose. Table 4.

Suggested insulin adjustment based on blood glucose (BG) in diabetic cats on long-term management

Blood glucose

Insulin adjustment

Nadir BG <4.5 mmol/L

- Reduce insulin by 0.5–1.0 iu/cat q12h if receiving 0.5–3 iu/cat q12h - Reduce by 25–50% if on a higher dose

Nadir BG >8.0 mmol/L

Increase insulin by 0.5–1 iu/cat q12h

Pre-insulin BG 8-10 mmol/L

Consider reducing insulin by 0.5 iu/cat q12h

Pre-insulin BG <4.5 mmol/L

Withhold insulin; if glucose rises appreciably later, give 30–50% of previous dose.

Primary goal of management The primary goal of management is to maintain blood glucose between a peak of 10–14 mmol/L and a nadir of 4.5–8.0 mmol/L The primary goal of management is defined above. It should be noted that: • During initial stabilisation the insulin dose should be increased gradually in steps of 0.5–1.0 iu/cat until the glucose nadir is 4.5–8 mmol/L

• If the glucose nadir is in the desired range, but the duration of insulin effect is consistently less than 8–10 h and there are clinical signs of inadequate glycaemic control, the cat should be switched to a longer acting insulin preparation. • Ideally blood glucose should be measured 5–7 days after any adjustment in insulin dose or change in insulin preparation. However, it should be repeated sooner (after 1–3 days) where there is a higher risk of hypoglycaemia (e.g. glucose nadir <4.5 mmol/L or pre-insulin glucose <8 mmol/L.) • Where blood glucose measurements are not possible, insulin adjustment should be made with extreme care. The dose should be increased in small steps (0.5 iu/cat q12h) no more often than every 7 days until clinical signs resolve and glucosuria is negative or reduced to trace amounts. Serial serum fructosamine concentrations should also be measured (Table 5). Most cats ultimately require insulin doses between 0.5 and 6.0 iu/cat q12h for diabetic control, but if the dose is >1.5 iu/kg q12h investigation of causes of insulin resistance should be considered (q.v.). Table 5.

Guide to interpretation of serum fructosamine concentrations in cats with diabetes mellitus*

Fructosamine concentration

General interpretation of glycaemic control

<350 µmol/L

Excellent glycaemic control or insulin overdose or diabetic remission

350–450 µmol/L

Good glycaemic control

450–550 µmol/L

Moderate glycaemic control

>550 µmol/L

Poor glycaemic control

* May not be increased in early or recent onset diabetes mellitus

Fructosamine concentrations reflect the mean blood glucose concentration over the preceding week (approximately) providing a helpful indicator of glycaemic control. Reference ranges differ between laboratories and measurement methods, but are around 200–360 µmol/L. Many factors can affect the measured fructosamine concentration: age, serum protein concentration, thyroid status, acid-base balance and hydration status. However, assessing fructosamine concentrations over time in an individual cat is valuable. Table 5 provides guidelines for interpretation.

Diabetic remission

If glucose is absent from urine and/or euglycaemia is maintained for 2–4 weeks without insulin, the cat is probably in remission. Detection and management of diabetic remission can be challenging. If urine is persistently negative for glucose, all blood glucose measurements are within the normal range (<~7.5 µmol/L) and/or serum fructosamine is <350 µmol/L, the insulin dose should generally be reduced by 0.25–1.0 iu/cat q12h every 1–2 weeks. With low or low-normal blood glucose concentrations, more rapid reduction (or temporary withholding of insulin therapy) may be required. When a dose of 0.5 iu/cat/day is reached (0.5 iu/cat q24h or 0.25 iu/cat q12h), and blood glucose remains normal, insulin administration should cease.

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If blood glucose measurements cannot be made, and remission is suspected in a well-regulated cat without glucosuria, the insulin dose may be slowly reduced (0.5–1 iu/cat q12h every 1–2 weeks), either until clinical signs or glucosuria reappear, or until insulin administration can be ceased. Cats in remission should remain on a low carbohydrate diet and should be monitored closely for recurrence of clinical signs. Regular blood glucose or urine glucose measurements (e.g. twice weekly initially) are recommended to be performed by the owner at home where possible.

Management complications Diabetic ketoacidosis (DKA) Not all cats with ketonaemia and ketonuria will have DKA, but cats with DKA will have a low blood pH and are unwell. A ketotic non-acidotic cat can be managed in the same way as a non-ketotic cat, but if DKA is present immediate hospitalisation with intensive treatment is required. The main objectives of treatment are to: • Correct dehydration and electrolyte deficits • Correct acidosis, using bicarbonate only if appropriate fluid therapy is insufficient • Provide adequate amounts of insulin to gradually stop ketogenesis and reduce hyperglycaemia • Provide a parenteral source of carbohydrate in vomiting animals and, when required, during insulin treatment • Identify precipitating factors in the disease process For these cats, a short-acting insulin preparation (e.g. regular/soluble insulin) is generally given either intramuscularly (IM) or by intravenous infusion. If regular/soluble insulin is not available, glargine may also be given IM or IV, although good data on its efficacy by these routes is lacking. When the cat is stabilised, insulin treatment is changed to a longer acting insulin and the cat managed as a stable diabetic. Hypoglycaemia Hypoglycaemia (blood glucose <3.0 mmol/L) occurs more often in diabetic cats than dogs and can be life-threatening. Owners should be advised on the signs (e.g. seizures, recumbency, anorexia, tremors, vomiting, ataxia, lethargy) and home first-aid treatment, including liberal application of honey or glucose to mucous membranes. Ideally, owners should keep dextrose gels (available from human pharmacies) at home, in case of hypoglycaemia. Severe hypoglycaemia appears to be more common in cats receiving >6 iu of insulin per day, and requires in-clinic management with parenteral glucose supplementation. A 50% dextrose solution is diluted 1:2 and an initial dose of 2–4 ml of the 25% solution (i.e. 0.5–1.0 g glucose) administered slowly IV over 5–10 minutes. Blood glucose should be monitored and further dextrose administered to effect. Euglycaemia should result in rapid clinical improvement, but treatment should still be followed with a 5% dextrose constant rate infusion, adjusted to maintain euglycaemia. If insulin therapy needs to be reinstated, this should be done cautiously with careful blood glucose monitoring.

The unstable diabetic A diabetic cat was considered unstable when: • There is a high insulin requirement (>1.5iu/kg per dose) • Unexplained increase in insulin requirement in a previously stable cat • Unexpected hypoglycaemia during stabilisation or in a previously stable diabetic cat • Difficulty monitoring glycaemic response where blood glucose results are inconsistent with the cat’s clinical signs There are many different problems that may contribute and the clinician must investigate the following: • Checking the owner’s insulin storage and administration • Reviewing the diabetic history to assess: - Starting dose of insulin - Type of insulin, duration of effect and blood glucose nadir - Over what time period insulin has been increased and by how much - BGCs (home versus in-clinic curves) - Fructosamine results - Monitoring of clinical signs, body weight change, dietary history, and any other medications that the cat is receiving • Further assessment for concurrent disease, to include consideration of: - Physical examination including body weight and body condition - Urinalysis and culture - CBC and serum biochemistry - Diagnostic imaging (including evaluation of the pancreas) - Feline pancreatic lipase assay - Evaluation for acromegaly (e.g. insulin-like growth factor-1 assay, growth hormone assay - Evaluation of thyroid function - Evaluation of adrenal function (e.g. low dose dexamethasone suppression test)

Owner Education Resources

The panel emphasised the importance of web-based resources for owners, which provide information on blood glucose sampling, insulin injection, urine collection and testing etc. www.icatcare.org www.youtube.com/user/icatcare Owner education is really important and the web can help!

References

Sparkes AH. Cannon M, Church D, Fleeman L, Harvey A, Noenig M, Petersen ME, Reuch CE, Taylor S, Rosenberg D. ISF Consensus guidelines on the practical management of diabetes mellitus in cats. Journal of Feline Medicine and Surgery 17, 255–250, 2015 (This paper contains all references that support or refute recommendations contained in this article. Read the original if you want further information or details. Free access on the JFMS website www.jfm.sagepub. com) Palm CA and Feldman EC. Oral hypoglycaemics in cats with diabetes mellitus. Veterinary Clinics of North America. Small Animal Practice 43, 407–415, 2013 (This reference is a review of the use and efficacy of oral hypoglycaemics in cats.)

Companion Animal Society Newsletter

Volume 27 Number 1

March 2016

Companion Animal Society Newsletter

Diskospondylitis – A case-based review Philomena Tuohy, BVSc, Zoetis Intern 2014, Veterinary Specialist Group Spinal pain is easily one of the most common reasons for a canine patient to be referred to see a surgical specialist and the makeup of the caseload referred for this reason to the Veterinary Specialist Group is no exception. Diskospondylitis; however, is not so common, with entities like intervertebral disc disease underlying the majority of cases investigated. When Archie, a young Labradoodle, presented during my internship for further assessment of spinal pain, he became a valuable demonstration of how important it is to go back to the basics of diagnostic reasoning in order to recommend and carry out the right testing and treatment. His case showed the importance of taking the complete signalment and history, compiling an appropriate differentials list and making sure a thorough physical examination is carried out. Archie’s case showed that regardless of where you are or what types of facilities you have at your disposal, all of the fanciest equipment cannot replace a full understanding of the typical signalment and etiopathogenesis associated with the common spinal cord diseases. Diskospondylitis is an infection of the intervertebral disc with concurrent osteomyelitis of contiguous vertebrae (Betbeze, McLaughlin 2002). It is a painful condition that may induce neurologic deficits because of extradural spinal cord or nerve root compression later in the course of the disease. It is usually seen in large breed dogs, although dogs of any size may be affected. Also males are twice as likely to be affected as female dogs. In most cases the cause is haematogenous spread of bacteria or fungi from a distant focus. Blood-flow through the vascular loops of the vertebral endplates and the disk space is sluggish and this is thought to predispose to colonisation of the area by pathogens. Occasionally the infection may originate from a migrating foreign body or develop from direct contamination from bite wounds or surgery.

Case: Archie

Archie, a 14-month-old male neutered Labradoodle presented to his regular veterinarian for assessment of pain of at least two months duration that his owners had been unable to localise. Archie appeared painful whenever his spine or abdomen was touched, they also noticed that over time he seemed depressed and was becoming more lethargic. Archie also appeared to have trouble sitting. On initial examination by his regular veterinarian Archie was pyrexic and appeared to have multiple sites of pain during clinical examination but reacted most significantly to spinal palpation. This is the typical description of an animal with diskospondylitis – a slow progression of clinical signs including hyperaesthesia, abnormal gait and reluctance to rise or ambulate. In the beginning, the pain may not appear localised or the owner may only

report a reduction in spontaneous activity. Weight loss, anorexia, depression and various degrees of neurologic deficits may be described in more advanced cases. Dogs with diskospondylitis often will show some response to a non-steroidal anti-inflammatory drug (NSAID) but will eventually relapse. Before specialist referral, Archie had shown a brief, positive response to an NSAID with the addition of gabapentin. This treatment failed to completely resolve the clinical signs so spinal radiography was performed at his regular veterinary clinic. Radiographs showed a narrowed intervertebral disk space at T9–T10. At this stage Archie was referred to VSG for further investigation.

The physical examination

Pyrexia, lethargy and significant spinal pain on palpation localised to the area of the thoracolumbar junction were the major findings of a comprehensive physical examination, including neurologic and orthopaedic examinations, carried out on Archie by a specialist surgeon. The pathogenesis of diskospondylitis often involves a nidus of infection at one or multiple distant sites. Thus in cases in which diskospondylitis is suspected, physical examination should include assessment of the ear canals, skin and teeth, rectal palpation of the prostate in males and cardiac auscultation in case a heart murmur were to be detected in the rare instance of bacterial endocarditis. Also, studies suggest that at least 47% of dogs with diskospondylitis have some degree of spinal cord compression resulting in an abnormal neurologic examination. Similarly, with the possibility of bacterial infection in multiple sites, including joints, abnormalities may be detected during an orthopaedic examination. An orthopaedic examination may also differentiate between an animal with a stiff, stilted gait from spinal pain from an abnormal gait associated with an orthopaedic condition, narrowing down the differentials list. Archie’s physical examination generated a problem list of: spinal pain, pyrexia and a radiographic lesion at T9–T10.

Forming a differentials list:

Once there was the suspicion that the source of the pain was spinal in location we considered the anatomic structures that can serve as a point of origin. Any disease that can affect form or function of any of the structures of the spine can be associated with clinical evidence of pain. Structures to consider include the meninges, intervertebral discs, vertebral facets, joint capsules, dorsal root ganglia, vertebral ligaments and the vertebral periosteum. A review of sources of spinal pain by Webb (2003), has a simple, yet effective, DAMNIT approach to identifying conditions of spinal pain. In Archie’s case, using the DAMNIT scheme to recall all the potential causes of his clinical signs was very useful.

p.p.tuohy@gmail.com, ph 0273058086

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March 2016

Companion Animal Society Newsletter

Just focusing on focal spinal pain: • Developmental: The vertebrae and their associated ligaments develop at approximately the same time. Instability may result from vertebrae not forming properly, or be enhanced by agenesis or malformations of spinal ligaments. Vertebral instability may result in malarticulations between vertebrae which may lead to abnormal wear and tear of joints or nerve root or spinal cord impingements – all of which may lead to pain. • Degenerative: When considering degenerative conditions we nearly always think of Intervertebral Disc Disease (IVDD). Intervertebral discs play an important role in spinal pain when they are compromised as they are partially innervated – the outer third of the fibrous ring is innervated by branches of the sinuvertebral nerve in rats, rabbits and dogs, as well as humans. Many structures become affected by an extruded or protruded disc, so multiple mechanisms come into play in this event. • Autoimmune diseases of the spine include steroid responsive meningitis and, with the joints of the spinal column being just like any other, they are also susceptible to idiopathic immune-mediated arthritis. • Neoplastic disease is possible but was considered unlikely in such a young animal. • Infectious causes include diskospondylitis from haematogenous spread or a migrating foreign body. • Trauma could be considered less likely given that Archie had no known history of trauma or spinal surgery.

Narrowing it down:

The signalment also provided important clues. We were considering a large breed, neutered, male dog. The dog was 14 months old, with a collapsed disc space (T9–10) and pain localised from the caudal thoracic to cranial lumbar spine. It was tempting to think intervertebral disc disease was the cause here. This is when history and signalment really came into play. With knowledge of the anatomy in this area we know IVDD is uncommon in this setting even if there is disc space collapse shown. This is mainly due to the long intercapital ligament extending across the heads of the ribs and therefore across the dorsal surface of the disks themselves. This structure sits between the disc and the floor of the vertebral canal. It is usually absent from the 1st, 11th, 12th and 13th ribs. Disc extrusions are consequently quite uncommon from in the T1– T9 intervertebral disc spaces. Archie’s radiographic lesion described at the ninth intervertebral disc space was therefore unlikely to be IVDD due to the area’s inherent stability with its additional ligamentous and osseous protection of the spinal cord. Also as Archie was so young, we could consider a degenerative aetiology such as IVDD less likely in this particular case, just as we would neoplasia. Another differential to consider at the time was meningitis. A degree of suspicion could have been reasonably justified with a dog that had both spinal pain and fever. However, meningitis did not explain the radiographic spinal lesion seen and there were no

obvious neurologic deficits detected so our short list of differentials for Archie was first, diskospondylitis then meningitis.

The Minimum Database:

Archie, though young, already had quite an extensive medical history, including gastrointestinal and infectious skin disease. This is not an uncommon finding in dogs with a clinical diagnosis of diskospondylitis due to the nature of the disease often requiring an initial focus of infection before haematogenous spread occurs. Blood Tests: Complete blood count and serum biochemistry panels were indicated as they may have shown signs of inflammation associated with an infectious process: a haemogram may show leukocytosis. There also may be a hyperglobulinemia. Urinalysis and Culture: Urinary tract infections are the number one concurrent issue in dogs with diskospondylitis. Thus urine should ideally be cultured after collection by cystocentesis and culture sensitivity testing results used to guide antibiotic therapy. Archie’s blood test results and urinalysis did not appear to show any evidence of significant systemic disease, however, he had only recently finished a seven-day course of amoxicillin/clavulanic acid. Negative culture results become difficult to interpret when antibiotic therapy has already been instituted. Care should also be taken when interpreting positive culture results as well – the organism isolated in the urine or the blood is not always the same as the organism affecting the disc. A wide variety of causative bacterial species have been identified in discospondylitis cases. This underlines the need to at least attempt bacterial isolation and sensitivity testing in every case. Staphyloccocus intermedius is identified most often. Other frequently documented bacterial species include Streptococci and Escherichia coli. Brucella may be isolated in other parts of the world. Fungal entities are more common overseas also.

Imaging:

Survey spinal radiographs are indicated in all patients with clinically detectable spinal pain. It is the most available imaging technique for spinal evaluation and can be used as an important screening tool to rule out the most obvious pathological conditions and then help dictate additional, more specific imaging studies. It is important to ensure patients are heavily sedated or anaesthetised which will increase the quality of the radiographs. Survey radiographs should ideally include the entire spine. It is estimated that 18-28% of diskospondylitis cases involve infection at multiple disc sites. The most common sites for diskospondylitis are reported as the cranial lumbar area and the L7–S1 disc space (Betbeze and McLaughlin 2002). Early radiographic signs of diskospondylitis include disc space narrowing and lysis of vertebral end plates. However, a clinically affected animal may be radiographically normal. The animal may present to a veterinarian 2–4 weeks before changes are able to be detectable radiographically. If the suspicion is high enough for the diagnosis of diskospondylitis

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March 2016

Companion Animal Society Newsletter

in a case and the clinical signs are progressive but the radiographs are initially normal, sequential radiography could possibly be the key to diagnosis. In this case Archie’s survey radiographs were inconclusive, with a narrowed intervertebral disc space on its own not specific enough for a diagnosis of diskospondylitis. Computed tomography (CT) is an excellent imaging modality for evaluation of spinal diseases involving the vertebrae (vertebral bony lysis and fractures). CT can also be useful in evaluating the paraspinal soft tissues. In Archie’s case, where the results of a survey radiographic exam were inconclusive, CT was the modality of choice (Figure 1). Since Archie did not show neurological signs it was assumed that there was no clinically significant extradural compression of the spinal cord. Thus myelography, which may reveal such compressive lesions, was not considered the best diagnostic step, despite also allowing sampling and analysis of CSF. Archie’s CT revealed extensive lysis and marked destruction of the vertebral end plates of T9 and T10. There was also associated sclerosis and early spondylosis with swelling of the surrounding soft tissue. The findings were consistent with an inflammatory process centred at the disc space and therefore the diagnosis of diskospondylitis was made based on these findings.

are other drugs resistant to β-lactamase. Archie was therefore prescribed continuing treatment with oral amoxicillin/clavulanic acid at approximately 20 mg/kg BID. In more severe cases, initial therapy may require parenteral administration of antibiotics or possibly surgical decompression. Once antibiotic therapy is started treatment should stay in place for 4–6 months at a minimum. According to a large retrospective study of diskospondylitis in dogs (Burkert et al. 2005), the median duration of treatment was 53.7 weeks – much longer than the suggested length of treatment in most literature. Results in terms of clinical improvement should be seen within 7 days of starting an appropriate and effective antibiotic. Pain relief in early cases is, surprisingly, usually only needed for a short time. Owners report significant improvement in their pet’s comfort within 3–4 days. Complications include wrong antibiotic choice, premature cessation of treatment, corticosteroid or other immunosuppressive therapies being used concurrently, as well as poor compliance. During resolution bridging spondylosis can be seen radiographically, which occurs in an attempt to stabilise the affected area. As lesions resolve they develop a rim of sclerosis adjacent to the lytic lesions in the endplates and disc space collapse may be seen due to fusion.

Archie’s outcome:

Figure 1. Archie’s CT showed lytic vertebral endplates on either side of the affected disk space with paraspinal soft tissue swelling.

Treatment: Antibiotic choice may be based on culture and sensitivity results if available. Empirical therapy can be started before these results become available by targeting the most common bacterial pathogen, Staphylococcus. Owners should be warned from the start that diskospondylitis has a long recovery time, especially if positive cultures cannot be obtained, as the wrong antibiotic selection may prolong the duration of treatment. This is exactly what was explained to Archie’s owners, as his urine culture returned with a negative result, presumably because of the 7-day course of amoxicillin/clavulanic acid that he had just finished. Amoxycillin/clavulanic acid is a good empirical choice for bacterial diskospondylitis, as

Archie is reported to be doing very well at home. His infection was responsive to amoxycillin/clavulanic acid, the initial antibiotic empirically prescribed. When Archie was clinical evaluated two weeks after treatment commenced there was a stark contrast to the depressed dog that presented initially, proving how quickly these cases can improve. His clinical signs did not return so radiographs were repeated 6 and 12 weeks following the start of treatment to assess for signs of lesion resolution. Following confirmation that there was no further progression of the lesion, antibiotic therapy remained in place for a further 4 weeks.

References

Betbeze C, McLaughlin R. Canine diskospondylitis: Its etiology, diagnosis and treatment. Veterinary Medicine 97, 673–681, 2002 Burkert BA, Kerwin SC, Hosgood GL, Pechman RD, Fontenelle JP. Signalment and clinical features of diskospondylitis in dogs: 513 cases (1980–2001). Journal of the American Veterinary Medical Association, 227, 268–275, 2005 Budsberg SC. Musculoskeletal infections. In: Greene C E (ed): Infectious Diseases of the Dog and Cat. 899–902, Saunders, Athens, USA, 2011 Shell L. Diskospondylitis – Associate Database. w w w.v i n . c o m / M e m b e r s /A s s o c i a t e /A s s o c i a t e . plx?from=GetDzInfo&DiseaseId=1211 (accessed 27 January 2015). Veterinary Information Network, Inc, Davis CA, USA, 2015. Webb AA. Potential sources of neck and back pain in clinical conditions of dogs and cats: A review. The Veterinary Journal, 165, 193–213, 2003

Companion Animal Society Newsletter

Volume 27 Number 1

March 2016

Companion Animal Society Newsletter

Brooke Woollett is a Technical Services Associate with Merial NZ

Survey of fleas, ticks and gastrointestinal helminths in cats and dogs in New Zealand Brooke Woollett, BAAT, Technical Services Associate – Companion Animals, Merial NZ Maureen Forsyth, DVM, MANZCVS, Technical Services Veterinarian – Companion Animal & Equine, Merial NZ Frederic Beugnet, DVM, PhD, Agregation, Dip. EVPC, Head of Global Veterinary Services Parasitology and Parasiticides, Merial Background

Ectoparasites (fleas and ticks) and endoparasites (gastrointestinal nematodes and cestodes) are a common and persistent problem for cats and dogs worldwide. In addition to their pathogenic effects, some parasites present a zoonotic risk and therefore control is important for both animal and human health. Treatment protocols should take into account epidemiological considerations as well as risk factors such as age and lifestyle. There is minimal current data on the prevalence of internal and external parasites of cats and dogs in New Zealand (NZ) and the prevalence of co-infestations. Historical research in New Zealand includes a survey of flea species prevalence carried out in 1981 (Guzman 1984) involving stray animals in the Wellington area and a winter flea survey conducted by Merial NZ in 19991. In Guzman’s study (1984) 99.2% of fleas collected from cats were Ctenocephalides felis, the cat flea, while the species harboured by dogs included 21.3% C. felis, 74.5% Ctenocephalides canis, the dog flea, and 4.2% Pulex irritans, the human flea. The Merial flea survey found that 28% of all pets examined in winter showed signs of flea infestation, and that C. felis was the most predominant flea species on both cats and dogs. The increased prevalence of C. felis is a trend mirrored around the world including Australia in which a 2010 survey of 291 cats and dogs from five states, identified 98.8% of fleas as C. felis (Slapeta et al. 2011). Research into the prevalence of gastrointestinal helminths includes a post-mortem survey carried out on fifty-five, 6–18-month-old dogs from eleven areas of NZ, which reported 38% were infested with Toxocara canis, 36% with Trichuris vulpis, 36% with hookworm and 6% with Dipylidium caninum (Collins 1981). A post-mortem study on 47 cats, identified Dipylidium caninum in 30%, Taenia taeniaeformis in 13%, Toxocara cati in 28% and Capillaria putorii in 15% (Collins 1973). A more recent survey, carried out in 2010, including 202 working sheep-farm dogs showed a 19% prevalence of infestation with one or more species of intestinal nematodes (O’Connell et al. 2013). From April 2014 to June 2015 Merial NZ conducted a nationwide parasite survey to determine the current level of challenge posed by common ecto and endoparasites of cats and dogs in NZ, and to assess the influence of risk factors on infestation.

Method

A total of 152 animals were enrolled in the multicentre study conducted in 16 veterinary clinics 1

Merial New Zealand, data on file

and three SPCA shelters from both the North and South Islands. Initially the aim was to include 300 animals in the study, however the stringent recruiting criteria and time commitment required for sample collection resulted in fewer pets enrolled. The month of the year that samples were collected was recorded. Selection criteria for owned dogs and cats included no external or internal parasiticide treatment during the previous two months and a generally healthy appearance. Healthy strays from shelters with no known history of parasiticide treatment were also accepted for inclusion. The number of fleas and ticks on each animal was estimated using a systematic five-minute combing technique. Flea infestation was confirmed by adult fleas on the animal or flea dirt (faeces) observed on the hair coat. A maximum of 10 fleas and 10 ticks were sent to NZ Biosecure laboratory for species identification. A faecal sample was collected and sent to Gribbles Veterinary Pathology for coproscopy comprised of gross examination and sugar solution centrifugal flotation. A questionnaire was completed by the owner or agent and, where known, detailed the animal’s age, lifestyle and frequency of parasiticide treatments. C. felis is the most common ectoparasite of cats and dogs and is also the intermediate host for the cestode Dipylidium caninum. Due to the poor sensitivity of coproscopy in diagnosing the prevalence of infestation in cats and dogs, two methods were utilised to investigate the presence of Dipylidium inside fleas. One hundred and nineteen fleas were dissected at NZ Biosecure for visualisation of D. caninum cysticercoid embryos and 186 fleas were sent to ClinVet in South Africa for PCR-specific testing for identification of D. caninum rDNA inside single fleas (Beugnet et al. 2014). Statistical analyses were performed by means of the Clopper-Pearson method. Risk factors were screened by contingency tables, Chi-squared tests and Fisher tests. A p value of <0.05 was considered as significant.

Results Overview The study included a total of 152 animals. Thirty-two cats and 36 dogs were client-owned pets and 66 cats and 18 dogs were from SPCA shelters. Ages ranged from 1 month to 17 years with 40% of cats under six months and 55% of dogs under 1 year. Where lifestyle was known, all cats and dogs had frequent access to outdoors, most lived with other animals in the same household and two-thirds lived in a sub-urban environment.

brooke.woollett@merial.com

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Companion Animal Society Newsletter

More than half (57%) of the dogs and the majority (88%) of cats in the study were infested with at least one endo or ectoparasite (Table 1). Fifteen percent of dogs and 12% of cats had co-infestations with both endo and ectoparasites. Table 1.

Observed prevalence of external and internal parasites in dogs and cats surveyed between April 2014 to June 2015. Cats (98)

Dogs (54)

At least one external or internal parasite

88%

57%

Ectoparasites Fleas (C.felis) Ticks (H. longicornis)

76% 6%

46% 7%

Endoparasites Gastro-intestinal nematodes T. cati T. canis T. vulpis Hookworm* Gastro-intestinal cestodes Protozoans Coccidia spp.

14% 11% NA NA 2% 0

19% NA 13% 6% 4% 0

Co-infestation External + internal parasites

12%

15%

*Eggs identified as hookworm, speciation not performed

Ectoparasites Shelter cats had a slightly higher prevalence of fleas than owned cats, 88% and 78% respectively, while shelter dogs were significantly more flea infested (78%) than owned dogs (42%). All cats with observed adult fleas had flea dirt while 11% with confirmed flea dirt had no observable fleas. Twelve percent of dogs with fleas showed no concurrent flea dirt and 15% of dogs with confirmed flea dirt had no observable fleas. A total of 589 fleas were collected for species identification. Ctenocephalides felis was the predominant flea infesting both cats and dogs and represented 99.5% of all fleas collected. C. felis was the only flea species harboured by owned cats and dogs in this study. One shelter puppy and kitten each had one C. canis flea in addition to C. felis. The same kitten and one kitten from another shelter had the only other flea species identified during the survey, Nosopsyllus fasciatus syn. Ceratophyllus fasciatus, the rat flea. The level of flea infestation through the seasons exhibited a temporal shift, peaking in summer with 92% of animals harbouring adult fleas, 76% in spring, 68% in autumn, and dipping to 49% in winter (Figure 1). Eighty-one percent of the cats surveyed in the North Island harboured adult fleas compared to 22% of South Island cats. Fifty-seven percent of North Island dogs and 9% of the South Island dogs had fleas. Thirty-four percent of cats with fleas and

Figure 1.

Prevalence of infestation with fleas by season

36% of dogs were observed to be harbouring 10 or more fleas. Twenty percent of dogs and 12% of cats had 20 fleas or more. Dogs in sub-urban environments tended to have a higher prevalence of flea infestation than dogs living in a rural environment, 71% and 44% respectively. Cats living in a sub-urban environment had slightly higher observed flea prevalence (86%) than those in a rural environment (74%). When comparing the ownerâ&#x20AC;&#x2122;s estimated frequency of flea treatments during the year and the presence of fleas, 58% of dogs having rare or no flea treatments were infested compared to 35% of dogs with occasional or frequent flea treatments. Cats with rare or no flea treatments also had higher observed flea prevalence than cats with occasional flea treatments, 91% and 67% respectively. No cats were classified as receiving frequent flea treatments. Tick prevalence showed a similar trend to fleas when comparing shelter versus owned dogs, with 22% shelter dogs and 0% owned dogs harbouring ticks. For cats, 3% of owned and 8% of shelter cats had ticks. Two shelter cats harboured over 20 ticks. All ticks collected came from animals in the North Island and were found during the months of July through March. All ticks submitted were Haemaphysalis longicornis (the NZ cattle tick) and all three life stages (larva, nymph and adult) were identified over the study period. Forty percent of animals with ticks harboured more than one life stage of tick at the time of examination, with one hosting all three life stages. With the exception of one cat, all animals with ticks were also infested with fleas. All adult ticks submitted were identified as female. Endoparasites Overall, 19% of dogs and 14% of cats surveyed tested positive for gastrointestinal nematodes based on coproscopy. The correlation between endoparasite infestations and the origin of dogs (shelter versus owned) and the frequency of deworming were significant. Dogs from shelters were more frequently infested (39%) than client owned dogs (9%) and dogs with rare frequency of deworming were significantly more infested (30%) than dogs reported as receiving occasional or frequent deworming (0%). Dogs less than one year of age had a higher observed prevalence of intestinal nematodes (22%) than dogs over one year of age (14%). Dogs living in a sub-urban environment had a higher prevalence of endoparasites than rurally based dogs, 25% and 7% respectively. However when considering solely owned dogs in the survey, the prevalence of endoparasites was 8% for suburban and 9% for rural dwellers. Faecal examination demonstrated Toxocara eggs in 11%, Trichuris in 6% and hookworm in 4% of dogs. Shelter cats showed 16% positive for nematode eggs compared to 9% of owned cats. Cats under one year of age had higher observed endoparasite prevalence than cats over one year of age, 17% and 9% respectively. A significant correlation was found between cat environment and endoparasite infestation: cats living in a rural environment were more frequently infested (26%) than sub-urban cats (5%). For solely client-

Companion Animal Society Newsletter

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Companion Animal Society Newsletter

owned cats, the prevalence of endoparasites was 7% for rural and 6% for suburban cats. Cats with a rare frequency of deworming were slightly more infested (9%) than cats reported as receiving occasional deworming (6%). Toxocara was the most common worm diagnosed in cats (11%), followed by hookworm in two cats and Capillaria species in one cat. Coccidia was identified in four cats. Eight percent of dogs and 6% of cats that were confirmed as hunters by their owners were positive for nematodes. Sixty-seven percent of all owned pets infested with nematodes were classified as non-hunters. No animals were identified with cestodes on coproscopy. Two percent of fleas sent for PCR tested positive for D. caninum and 8% of the fleas dissected were labelled suspicious for containing tapeworm embryos. Co-infestation A total of 15% of dogs and 12% of cats harboured both ectoparasites (flea and/or ticks) and intestinal worms (roundworm, hookworm, whipworm). This is very close to the prevalence expected by chance given the observed prevalence for both ectoparasites and endoparasites. Nine percent of owned animals were co-infested compared to 19% of shelter animals.

Discussion The survey confirms that fleas flourish year round under the New Zealand climate, with 49% of untreated cats and dogs harbouring fleas during winter. C. felis is the predominant flea species and was the only species found on client-owned pets. This follows the trend of a steady decline of C. canis demonstrated in the Merial 1999 winter survey and the 2010 Australian flea survey. The ‘cat flea’ can be found on a variety of wild and domestic hosts and has a broad range of ideal temperature and relative humidity that support its stages of flea development and survival year round (Guerrero 2009). Cats tended to have less claimed flea treatments than dogs during the year and may explain the higher observed prevalence of flea infested cats. The risk factor for flea infestation when comparing suburban versus rural environment can vary greatly in significance and is likely influenced by multiple host habitat factors such as a house versus apartment dwelling (Gracia et al. 2013). In this study, dogs living in suburban environments tended to have a higher prevalence of fleas and may reflect the closer proximity of houses and increased socialisation in common pet areas such as dog parks, gardens and reserves. In this study, fleas and flea dirt were found alone on some animals. The amount of flea dirt was not quantified but its presence indicates recent exposure to fleas, with a natural death or grooming. Finding fleas but no visible flea dirt is possible in the early stages of flea exposure or as a result of grooming. The only tick species identified was H. longicornis and was observed starting in July, with peak numbers during October through March. All animals with ticks

were from the upper North Island (from Hamilton to Whangarei) which is consistent with known climatic regions of NZ suitable for tick survival. Forty percent of animals with ticks harboured more than one life cycle stage. Overlapping of seasonal activity is not uncommon to find in NZ and reflects the variable bioclimatic parameters that effect tick survival and activity (Bingham 2015). Temperature and photoperiod largely dictate the timing and duration of activity and NZ has experienced a slight increase in annual temperatures during the past fifteen years. H. longicornis is represented by various genetic races. It is the obligate-parthenogenetic triploid race that is established in NZ, resulting in the emergence of only female adult ticks (Bingham 2015). All adult ticks in this survey were identified as female which is consistent with a genetic triploid race. H. longicornis is the only recognised tick species of mammals in NZ. In 2015 Rhipicephalus sanguineus (the brown dog tick) was identified by biosecurity agents, on two dogs in Christchurch and one dog in Wellington (MPI 2015, Heath 2015). This species is not established in NZ and the origin of these ticks remains unknown and no further observations have been reported. Toxocara spp. was the most commonly diagnosed gastro-intestinal worm in both cats and dogs. There was a higher prevalence in young animals, but animals of all ages were infested, including a 17-year-old dog that also had whipworm and hookworm eggs identified. Toxocara species pose a zoonotic risk to humans through ingestion of embryonated eggs from the environment. Humans act as a paratenic host in which Toxocara larvae migrate to tissues and organs including the brain and eyes, causing visceral larva migrans and ocular larva migrans; the epidemiological importance of adult dogs and cats as a reservoir of infection should not be underestimated (Overgaauw and van Knapen 2013). A recent European study of owned cats identified outdoor access as a risk factor for both internal and external parasites and cats of a young age and living in a household with three or more cats had an increased frequency of T. cati infection infestation (Beugnet et al. 2014a). In this study, living with other pets was not a relevant risk factor for flea infestation and likely explained by the fact that close-contact is not needed for flea transmission. In NZ all of the animals surveyed had frequent outdoor access and the majority were living in households with other animals. This may explain a similar prevalence of endoparasites infestation for owned pets regardless of rural or suburban habitat or hunting status. While significant risk factors for both ecto and endoparasites in this survey included shelter status and age under one year, these two demographics overlapped as the majority of shelter animals were less than one year of age. The data from shelter animals provides insight to the level of potential risk of multiparasitism that is present in the environment. Overall client-owned pets had a lower prevalence of both endo and ectoparasites

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Companion Animal Society Newsletter

than shelter animals and pets claimed receiving more frequent anti-parasiticide treatments had the lowest prevalence. This trend reflects the study Beugnet et al. (2014a) where cats receiving no anthelmintic treatment were significantly more at risk for T. cati infestations than cats receiving one or two treatments per year, themselves being significantly more frequently infested than cats receiving more than 3 treatments per year. In addition cats treated with an anti-flea product more than 4 times a year were significantly less at risk for flea infestations than cats receiving less than 3 treatments a year. Fleas are the intermediate host of D. caninum, the most common tapeworm infecting dogs and cats in NZ. To help assess the risk from fleas, two methods were used to investigate the level of Dipylidium infection in fleas. The dissection of fleas was labour intensive for the laboratory entomologist and the presence of immature stages of tapeworm could not be positively identified; the PCR testing was simple and specific for D. caninum. In this survey 2% percent of fleas were positive on PCR which is similar to a large European study in which 2.2% of the C. felis fleas collected on cats and 5.2% on dogs were positive for Dipylidium (Beugnet et al. 2014b). Taenia spp. is the group of cestodes that can commonly infect dogs and cats in NZ when they ingest tissue from an intermediate host such as rodents or ruminants. Farm dogs fed offal and scavenging or cats and dogs that hunt will be at risk for these tapeworms.

Summary The data collected from this survey provides information regarding the prevalence of common internal and external parasites infesting cats and dogs in NZ and will be of benefit to veterinarians when providing parasite advice to pet owners. Fleas are prevalent year round with almost 50% of animals infested during winter and both sub-urban and rurally-based pets are at risk. C. felis accounted for 99.5% of all fleas identified and was the only flea species found on client-owned pets. The presence of fleas or flea dirt can be found together or alone, and should be considered indicators of current exposure to flea infested environments. Gastrointestinal nematode infestations continue to be prevalent in cats and dogs in NZ despite the availability of anthelmintics. As some intestinal nematodes pose a zoonotic threat regular worming of cats and dogs is important to minimise the shedding of eggs and contamination of our shared environments. Young animals have a higher risk of Toxocara infections but animals of all ages can become infected. Fleas, ticks, roundworm, hookworm and whipworm are common parasites for dogs and cats in NZ as well as co-infestations. An increase in frequency of parasiticide treatments tended to correlate with a reduced prevalence of endo and ectoparasites respectively.

The risk of cestode infections is determined by the risk of ingestion of an intermediate host and will differ for each individual animal. The most common tapeworm of cats and dogs is the flea tapeworm which can be effectively controlled with consistent flea control. The pets in this survey had frequent and often unlimited access outdoors and lived in multi-pet households. It is likely most pets in New Zealand would enjoy a similar lifestyle and would therefore benefit from regular external and internal parasite treatments advocated by NZ veterinarians.

Acknowledgments We would like to thank the staff of the participating veterinary clinics and SPCA centres for their support and time with recruiting cats and dogs into the study and collecting samples.

References Beugnet F, Bourdeau P, Chalvet-Monfray K, Cozma V, Farkas R, Guillot J, Halos L, Joachim A, Losson B, Miro G, Otranto D, Renaud M, Rinaldi L. Parasites of domestic owned cats in Europe: co-infestations and risk factors. Parasites & Vectors 7: 291, 2014a Beugnet F, Labuschagne M, Fourie J, Guillot J, Farkas R, Cozma V, Halos L, Hellmann K, Knaus M, Rehbein S. Occurrence of Dipylidium caninum in fleas from client-owned cats and dogs in Europe using a new PCR detection assay. Veterinary Parasitology 205, 300–6, 2014b Bingham. Quarterly report of investigations of suspected exotic diseases. Surveillance, 42 (3), 47–55, 2015 Collins GH. A limited survey of gastro-intestinal helminths of dogs and cats. New Zealand Veterinary Journal, 21, 175–176, 1973 Collins GH. A survey of gastro-intestinal helminths of dogs in New Zealand. New Zealand Veterinary Journal, 29, 163–164, 1981 Gracia M, Calvete C, Estrada R, Castillo J, Peribanez M, Lucientes J. Survey of flea infestation in cats in Spain. Medical and Veterinary Entomology 27, 175–180, 2013 Guerrero J. Canine flea and tick control. A reference guide to EPA-approved spot-on products. Technical Monograph. www.hartzultraguard.com, The HARTZ Mountain Corporation, Secaucus, New Jersey, 2009 Guzman RF. A survey of cats and dogs for fleas: with particular reference to their role as intermediate hosts of Dipylidium caninum. New Zealand Veterinary Journal, 32, 71–73, 1984 Heath ACG. Biology, ecology and distribution of the tick, Haemaphysalis longicornis Neumann (Acari: Ixodidae) in New Zealand. New Zealand Veterinary Journal, 64, 10-20, 2016 MPI [Ministry for Primary Industries]. Pests & Diseases: Brown dog tick. http://www.biosecurity.govt.nz/pests/browndog-tick. Accessed 18 June 2015. O’Connell A, Scott L, Cogger N, Jones B, Hill K. Prevalence of gastrointestinal nematode and protozoan parasites, body condition scores of working sheep dogs in New Zealand in 2010. Proceedings of the International Sheep Veterinary Congress. Pp 126, 2013 Overgaauw P, van Knapen F. Veterinary and public health aspects of Toxocara spp. Veterinary Parasitology 193, 398-403, 2013 Slapeta J, King, J, McDonell D, Malik, R, Homer, D, Hannan, P, Emery D. The cat flea (Ctenocephalides felis) is the dominant flea on domestic dogs and cats in Australian veterinary practices. Veterinary Parasitology 180, 383-8, 2011

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Volume 27 Number 1

This article was written as part of the requirements for receiving the CAS/Hills Pet Nutrition Educating the Educators Scholarship

Conference Report: 29th American Veterinary Dental Forum 2015 Geraldine Gorman, MVB MANZCVS Small animal dentistry and oral surgery Held in Monterey, California at the end of Oct 2015 and doubling as the 13th World Veterinary Conference this event was essential viewing for anyone with an interest in veterinary dentistry and oral surgery. It attracted an attendance of over 1100 registrants from all continents. The six concurrent streams, delivered by world class speakers, meant that there was a wide choice of lectures and wet labs to attend at any one time and topics in small animal, equine, and exotic animals were covered at fundamental, intermediate and advanced level. Technicians and marketing/ management were also well catered for. Over 60 trade stands, most connected to veterinary dentistry made lunch breaks extremely interesting and busy. It was a time to meet and greet, browse products and equipment, ask questions and spend money! The fundamental stream, while targeting mainly general practice veterinarians wishing to get started in dentistry, provided information valuable to anyone doing veterinary dentistry. Beginning with talks on client compliance and dental equipment it also covered basics like charting, positioning for dental radiographs, regional oral nerve blocks, extractions and dental pathology. Intermediate level participants were brought through the intricacies of periodontal flap surgery by the entertaining Brooke Niemiec. Maxillary repair techniques were simplified by Loic Legendre. Numerous lectures on extractions and their complications proved extremely popular as always. Antibiotic use, post-operative pain medication and anaesthesia were well covered. Oronasal fistulas, maxillectomy and mandibulectomy, vital pulp therapy, rotary endodontics and composite restorations all featured, as well as the ever popular lingually displaced mandibular canines. The advanced sessions were preceded on Day 1 by the very well attended â&#x20AC;&#x153;On the Cuspâ&#x20AC;? lecture by guest speaker Dr Gregory Farwell MD, FACS, director of Head and Neck Oncology and Microvascular Surgery at University of California, Davis. His 2-hour session gave an insight into the work being done in humans in the management of head and neck malignancies to optimise patient functional and cosmetic outcomes. He showed that the starting point in many of the cases was the correct realignment of the dentition which led to the best return to normal structure and function. While many of the advanced sessions dealt with maxillofacial reconstruction they also found time to discuss oral inflammatory diseases of dogs and cats, difficult anaesthesias, orthodontics, bone grafting,

lasers and stem cell therapy for Feline Chronic Gingivostomatitis. There was a choice of 19 labs ranging from technicians and basic techniques for general practice veterinarians right up to residents in training level. Subjects included extractions in the dog and cat, radiography, periodontal flap surgery, orthodontics, regional nerve blocks, zoo/captive wild animal dentistry, oral surgery, equine radiography, restoratives, charting, maxillary fracture repair and equipment sharpening and maintenance.

Highlights and interesting snippets Mouth gags in cats Judy Force presented a summary of recent research in the last few years with relevance to the dental patient that should affect how we anesthetize and manage our canine and feline dental patients. Many veterinarians use spring-loaded mouth gags to improve visibility and access, especially in the small mouths of cats. These have been shown to be associated with the development of central neurological deficits, including blindness. In this species, the maxillary arteries are the main source of blood supply to the retinae and brain. Springloaded gags generate constant force after placement that could contribute to bulging of the soft tissues between the mandible and the tympanic bulla. Under these circumstances, the maxillary arteries can become compressed as they course between these osseous structures. Electroretinography (ERG) and magnetic resonance angiography (MRA) were performed in healthy cats with different types of mouth gags. Maximal opening of the mouth caused alterations in several indicators of blood flow in some individual cats. No changes were observed with smaller gags. The force applied against the mouth was significantly higher with the spring-loaded gag than with any other gags but even a 42mm plastic mouth gag caused circulatory changes. Judicious use of prophylactic antibiotics in dentistry and oral procedures J.W. Soukup clarified the situation on antibiotic use in dental patients. The oral cavity is a potential reservoir for bacteraemia. Antibiotic prophylaxis for the prevention of bacteraemia associated with dental procedures is a common practice among veterinarians. Bacteraemia most often causes no clinical signs and resolves spontaneously without treatment. Rarely, metastatic infectious foci may develop and lead to more serious consequences such as infective

Pet Dental Vet Ltd, gg4vet@hotmail.com, mob 021-120-3150. Bay of Islands Veterinary Services, Shop 3, Selwyn Road, Paihia, Bay of Islands. 09-402-8584

March 2016

Companion Animal Society Newsletter

endocarditis (IE) or prosthetic joint infections (PJI). Bacteraemia can be provoked by dental procedures but in one study the rate of bacteraemia in a group of dogs undergoing prophylactic dental treatment or extractions was the same as that in two different control groups of dogs which had no dental procedure. In addition bacteraemia rates in humans from common daily activities such as chewing, tooth brushing and flossing have reached 68% in some studies. It has been estimated that cumulative effect of bacteraemia from routine daily activities may be as high as 5.6 million times that resulting from a tooth extraction. “No prospective, randomized, placebocontrolled studies exist on the efficacy of antibiotic prophylaxis to prevent IE in patients who undergo a dental procedure”. On the other hand there are many negative aspects to the routine use of prophylactic antibiotics not least of which is the problem of antimicrobial resistance. Recent updated guidelines from the American Heart Association & European Society of Cardiology recommend a significant reduction in the use of prophylactic antibiotics and in patients that require them they should only be used in cases that “involve manipulation of the gingival tissues or the periapical region of teeth or perforation of the oral mucosa”. Because there is little evidence to clearly link dental procedures and IE and the effectiveness of antibiotic prophylaxis is unproven, due to the risks to the patient and the risk of contributing to the worsening of global antimicrobial resistance, the routine practice of antibiotic prophylaxis should be seriously curtailed and limited to a very select group of patients. Such patients are those with severe congenital or degenerative cardiovascular disease that undergo dental cleanings that cause haemorrhage, any oral or periodontal surgery or endodontic surgery. Because the bacteraemia should only last 2 hours a single IV dose of an appropriate antibiotic is recommended and there is no justification for pre- or post-operative oral dosing. Dental Radiography The importance of dental radiography was once again emphasised in many of the lectures especially with regard to extractions. For example; • The true extent of periodontal disease can only be determined by taking dental radiographs. • Approximately 10% of feline maxillary third premolars have a third root. • Dentoalveolar ankylosis, which makes extraction by traditional elevation practically impossible, can only be diagnosed by dental radiography (Figure 1). In such cases, crown amputation and intentional root retention is acceptable for advanced Type 2 feline tooth resorption, but it is important to make this distinction prior to making treatment decisions. • Fractured teeth, missing teeth, periapical lesions on apparently healthy tooth roots and neoplasia of the mandible or maxilla are all situations where

intraoral radiography is a vital tool in reaching a diagnosis and formulating an appropriate treatment plan.

Figure 1. Radiograph of the left mandible in a cat showing dentoalveolar ankylosis of the 4th premolar tooth.

Lingually displaced mandibular canine deciduous teeth in dogs Norman Johnson’s very practical presentation discussed the increase in presentation of lingually displaced mandibular canine teeth in pups in general practice. The Staffordshire bull terrier is one of the commonly affected breeds and it is now believed that the condition is associated with an inheritable complex autosomal recessive mutation that requires both sire and dam to both be recessive carriers for the litter to have pups appearing with the condition. Varying degrees of severity occur with extreme cases having the deciduous mandibular canines occluding into the soft tissues of the hard palate. Many times these pits are medial to the deciduous maxillary canines. This is a painful condition and early intervention not only alleviates the discomfort for the affected animal but also removes the dental interlock between maxilla and mandible and allows the mandible to grow independently again. The third benefit is that the permanent mandibular canines which erupt lingually to the deciduous teeth have a clear path to erupt and have less chance of repeating the situation. He recommends that surgery is performed as soon as possible after the problem is recognised to ensure enough time for the treatment to have benefit – normally around 10 weeks. The deciduous mandibular canines should be fully erupted by 6 weeks of age and the permanent mandibular canines usually start erupting at 22 weeks of age or so (Wiggs 1997). After 16 weeks of age surgical removal is more difficult once the bone mineralises. This is a surgical extraction requiring a buccal mucogingival flap and gently shaving the bone of the length of the curved tooth root. Up to 16 weeks old this is possible using a hand chisel only as the bone is soft. Care is taken to avoid damaging the unerupted permanent tooth and the flap is sutured using 5/0 monocryl sutures. Monitoring the eruption of the permanent teeth is needed and sometimes these may

Companion Animal Society Newsletter

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also require proactive intervention to assist them attaining the correct occlusion. In milder cases ball therapy may be used by the owner to tip the teeth more buccally (Verhaert 1999).

Tracheal ruptures are especially common in cats, possibly due to turning the patients without disconnecting the endotracheal tube (ET) and/or over inflation of high pressure, low volume ET tubes.

In cases where the permanent mandibular canines are lingually displaced Dr. Johnstonâ&#x20AC;&#x2122;s favoured treatment modality is crown amputation and partial coronal pulpectomy and he continued to describe this is detail. This option has many advantages over the others available in that the whole of the root and most of the crown is retained. Pain is eliminated and the soft tissue damage is alleviated in one procedure. The pulp remains alive, the dentine wall strengthens naturally over time and the success rate using MTA (mineral trioxide aggregate), as he does, is very high (92%).

Corneal ulceration occurs due to drugs which impair blinking leading to desiccation of cornea and erosions, contact with products used in endodontic procedures, overzealous use of air/water syringe near the eyes and contact with sharp instruments. After an hour under general anaesthesia tear production may drop to zero so regular use of eye lubricants is very important.

Complications related to anaesthesia for dental patients Maria M. Soltero-Rivera and Alexander M. Reiter discussed the risk of complications particularly in relation to dental procedures. Unfortunately the conscious examination of the animal only reveals part of the picture and in most oral and dental conditions general anaesthesia is usually required for the full diagnosis and treatment. Every general anaesthetic carries a small degree of risk even in healthy animals with reported mortality rates of 0.1â&#x20AC;&#x201C;2% of dogs and cats. However dental procedures have a higher rate of complications risk and even though many are not life threatening they are often avoidable.

March 2016

Swelling of the tongue due to severe inflammation or trauma may obstruct breathing after extubation. This may be treated by wrapping the tongue with gauze sponge soaked in hypertonic solution. Tracheostomy may be necessary. Fatal air embolism has been reported in a cat (possibly associated with over use of the air syringe) during extraction of the mesiopalatal root of the maxillary 4th premolar tooth. This short summary only covers a few take home points from an excellent world class conference and I felt very privileged to be able to attend. I am very grateful to CAS, Hills Pet Nutrition, AVABS and Vetlearn for contributing to my costs via the Educating the Educators scholarship.

Companion Animal Society Newsletter

CAS Specialist Profile – Robyn Gear

The CAS Specialist Profile is a regular feature in the CAS newsletter, aiming to provide an insight into the paths NZ veterinarians have taken to achieve specialisation. In this issue Hannah Bain talks to Robyn Gear who is a registered specialist in Small Animal Internal Medicine. She has been a registered specialist since 2004. What is your specialty, and how many years have you been practicing as a registered specialist? I am a small animal internal medicine specialist and have been since 2004. I was first registered as a specialist in New Zealand in 2009 when I moved back from the UK.

What is the most challenging part of your job? Communicating the multiple different aspects of a patient’s workup, outcomes and cost and ensuring these are all covered and understood in each consultation is challenging.

Where did you obtain your veterinary degree, and did you move directly into a residency from there? I graduated from Massey and then worked for a couple of years in small animal general practice in New Zealand before going on my OE.

I also find my work/life Dr. Robyn Gear, BVSc, DSAM, DECVIMbalance challenging. I CA, Registered Specialist in Small Animal work part time as I have Internal Medicine a young family but I find it very difficult to leave work at work!

What drove you to specialise, and why did you choose internal medicine? While in general practice I always wanted to know and learn more than I felt I did. It was hard to do all the reading and research I wanted to do in general practice so it was a natural progression to focus in on one area and do further training. I chose internal medicine as I enjoy problem-solving and have always enjoyed the debate of a specialty that is not black and white.

What advice would you give to someone thinking of specialisation? Pursue an area you are passionate about but also think about where you want to be in 5 to 10 years time and what opportunities there will be. Talk to specialists, contact universities or private practices who offer specialisation and see what requirements they need.

Explain the process you took to become a registered specialist (briefly include duration, location, how you found the experience, challenges). I initially did a 1-year rotating small animal, general internship at the Royal Veterinary College in London. This involved 1 in 3 weeks on nights which was challenging but very rewarding treating critical care patients in a busy ICU with a great team. I then undertook a 3-year Small Animal Internal Medicine Residency at Cambridge University. Residencies at universities allow you to become immersed in clinical work, teaching and research. The departments work closely together and the debate within and between departments is fun. The exposure to very experienced clinicians, research at the forefront of veterinary medicine and the collegiality with other residents is very rewarding. The challenges were definitely the exams, luckily now a distant memory. What do you like most about your job? The enjoyment and satisfaction I get from my job is still the problem solving and case discussions with first opinion vets and colleagues. I enjoy being able to help my patients, clients and colleagues both out in practice and within the practice I work. I offer phone and internet consults to vets in practice which allows me (I hope) to help them and their patients and gives me the flexibility to work some hours from home. What is the worst part of your job? Unfortunately workups for our patients can be expensive, stressful and unpredictable. Discussing costs at this emotional time is usually the worst part of the job.

What do you think about vets specialising later in their careers, after a significant period of time in general practice? I have always recommended that veterinarians spend some time in practice prior to specialising to ensure that they have an understanding of the challenges of first opinion practice. However, as you spend more time in a job you can be more set in your ways and there is a perception that these people are harder to train. People in other professions often can have 2–3 careers in their working lives and I think veterinarians also want further challenges as their lives progress. Priorities may also switch from family commitments to career as we get older. Traditionally vets have specialised earlier in their careers but it will be interesting to see if this changes as our professional demographic changes. Ultimately it is going to be the employers who determine the residents they train! Do you think NZ needs more specialists, and if yes, in what areas? Yes – there are many specialties and subspecialties that our patients would benefit from: neurologists, cardiologists, oncologists, radiologists, dermatologists and clinical pathologists. It’s always going to come down to what our population size is and therefore the demand to sustain various specialities. What are your passions outside of work? I’m passionate about wildlife and the environment. I love spending time outdoors with my family whether it is running, tramping, on the kayak or lying on the beach!

Robyn can be contacted at Vet Response, ph 0210515215, robyn@vetresponse.co.nz, www.vetresponse.co.nz

Companion Animal Society Newsletter

Volume 27 Number 1

New Zealand Veterinary Journal: Companion Animal Digest Volume 64, Issue 2, 2016

Sarah Fowler, BSc, Msc, PhD, BVSc, CAS Newsletter Editor Here we present brief summaries of the articles from the most recent issue(s) of the New Zealand Veterinary Journal that are likely to be of interest to companion animal veterinarians. Remember, even if you are not a subscriber to the print version of NZVJ, all NZVA members have free online full-text access to the NZVJ at http://www.sciquest.org.nz/nzvj The January 2016 issue of the NZVJ (64(1)) was entirely devoted to the recent and ongoing outbreak of bovine anaemia associated with Theileria orientalis in New Zealand. As such there were no articles in this issues pertaining to companion animals. However this collection of articles presents and interesting and thorough review of the early stages of a significant recent outbreak of veterinary disease in NZ and is worth a look.

What do vet nurses and technicians really think about post-op pain in dogs and cats?

Attitudes and perceptions of veterinary paraprofessionals in New Zealand to postoperative pain in dogs and cats K Kongara, HE Squance, IA Topham and JP Bridges Pages 112-116 Why they did it Knowledge of the attitudes and perceptions of NZ veterinary paraprofessionals (ie nurses and technicians) to post-operative pain in cats and dogs would allow identification of areas that may require improvement. This paper reports a survey assessing these attitudes. What they did The authors invited veterinary paraprofessionals in NZ to participate in an online survey. The survey contained a variety of questions about demographic information, the respondents’ assessment of pain after commonly performed surgeries in dogs and cats, their opinions on provision of analgesia, who had responsibility for pain monitoring and the use of any formal pain scoring system in the practice in which they worked. What they found 165 responses were analysed, (98% of whom were female). Of the procedures asked about fracture repair in dogs and repair of diaphragmatic hernias in cats were seen as the most painful. Cats were seen as experiencing less pain from neutering than dogs. All respondents agreed that animals benefit from perioperative analgesia. Ninetythree percent of respondents reported that their knowledge of pain and analgesia could be better. Take-home message While this survey suggests that the need for perioperative analgesia is well recognised among veterinary paraprofessionals in NZ, it also suggests that this is an area CPD providers should be giving focus to, given that a large majority of respondent thought that their knowledge in this area could be improved.

March 2016

NZ cats and their collars

Use and perception of collars for companion cats in New Zealand M Harrod, AJ Keown and MJ Farnworth Pages 121–124 Why they did it A good knowledge of how clients care for their cats and the perceptions that lead to these practices may help veterinarians provide better care for their feline patients. There is currently very little information about the use of collars on companion cats in NZ. What they did The authors distributed an online survey (via email and social media) to members of the NZ general public. The survey contained questions about respondent’s demographic details, cat ownership and a number of questions regarding the use of collars on cats. Since the survey was based on a self-selected group of respondents conclusions can only be drawn about the group of people who responded and cannot be extrapolated to the NZ wider population. What they found Of the 77% of respondents that were currently cat owners, 89% allowed their cat(s) at least some access to the outdoors. Only 36% used a collar on at least one of their cats. In contrast 54% had at least of their cats microchipped. The most common reasons given for using a collar were to reduce predation and for identification while common reasons given for forgoing collars were the cat’s intolerance, collar loss and concerns about collar safety. Significant differences were found between cat owners and non-owners in their opinions on cat management. Take-home message Among the people who responded to the survey, use of collars on cats was low with more using microchips for identification. A large majority of the cats in the survey were out-door cats.

Companion Animal Society Newsletter

“What is your diagnosis?” The answer (From page 12)

What abnormalities can you identify in the radiograph? • Decreased visualisation of serosal surfaces and margin with increased intra-abdominal fluid opacity • The outline of the bladder is not readily identifiable • Loss of detail within the thorax with suspected pleural effusion • The caudoventral aspect of the heart can be visualised indicating a possible ventral mass effect on the heart • The integrity of the diaphragm cannot be accurately identified in this radiograph

What are your differential diagnosis for your radiographic findings?

Differential diagnosis for peritoneal effusions in this patient (Frank and Mahaffey 2007; Nelson et al. 2014a) • Uroabdomen: trauma to the kidneys, ureters, bladder and/or proximal urethra • Hemoabdomen: traumatic, coagulopathy • Septic peritonitis secondary to traumatic damage to the gastrointestinal tract • Feline infectious peritonitis • Ascites secondary to portal hypertension • Chylous effusion secondary to trauma Differential diagnosis for pleural effusion in this patient (Thrall 2007; Nelson et al. 2014b) • Pure and modified transudates: hypoalbuminemia, diaphragmatic hernia • Nonseptic exudates: feline infectious peritonitis, chronic diaphragmatic hernia, lung lobe torsion, resolving septic exudates • Chylous effusion: Secondary to trauma, diaphragmatic hernia &/or lung lobe torsion • Hemorrhagic effusion: trauma, bleeding disorder, lung lobe torsion

This patient had not urinated since presentation to the referring veterinarian with pain localised to the hindend. Radiographic findings have identifed development of peritoneal and pleural effusion with difficulty accurately identifying the bladder. The top differential for the peritoneal effusion, given the appearance of the abdominocentesis noted by the primary clinician, is a uroabdomen. Likely differentials for the pleural effusion following suspected trauma include haemorrhagic and chylous effusions and/or diaphragmatic compromise with urinothorax. Further diagnostic testing is required for a definitive diagnosis.

What further testing could you perform?

A blood sample was taken for serum biochemistry analysis (Table 1). Significant findings included: • Elevated creatinine kinase indicating muscle disease/damage • Azotemia suspected to be post renal in origin • Electrolyte abnormalities including hyperkalemia and hyperphosphatemia suspected to be secondary to decreased excretion

These findings are supportive of a tentative diagnosis of bladder rupture with uroabdomen. Table 1.

Serum biochemistry results. Result

Note

Reference

Test

9164

0 – 344

Units IU/L

AST

0 – 66

IU/L

0 – 85

IU/L

ALP

ALT

189

0 – 100

IU/L

BIL

0–5

umol/L

63 – 83

g/L

ALB

28 – 42

g/L g/L

GLO

27 – 49

AGR

1.00

0.6 – 1.6

–

URE

84.7

5.7 – 12.9

mmol/L

CRE

633

70 – 159

umol/L

PO4

4.75

1.30 – 2.80

mmol/L

2.14

1.81 – 2.70

mmol/L

CHOL

3.8

1.5 – 6.0

mmol/L

145

147 – 156

mmol/L

9.2

3.5 – 5.0

mmol/L

107

108 – 128

mmol/L

GLU

13.3

3.9 – 6.1

mmol/L

Abdominocentesis and thoracocentesis and analysiss of the fluids obtained. This will allow the type of fluid (blood, urine, transudate, modified transudate, exudate) to be determined facilitating diagnosis of the underlying cause of the fluid accumulation. In this case unfortunately the in-house fluid examination, protein assessment and cytological examination results are not available. Typically fluid suggestive of uroabdomen will range from a transudate to an exudate depending on the chronicity and severity of disease (Connally 2003). Urine is a chemical irritant within the abdomen and can result in nonseptic neutrophilic inflammation. Typically fluid analysis following abdominocentesis will reveal a cell count >5000 nuceleated cells per microliter, specific gravity of >1.025 and total solids of >3.0 g/dL (Stafford and Bartges 2013). However creatinine levels in the abdominal and thoracic fluid samples were measured. In this patient the abdominal fluid creatinine concentration was 1266 μmol/L and the fluid creatinine:serum creatinine ratio was 2:1. The absolute creatinine level in the abdominal fluid was 8-fold the upper serum reference value. The fluid obtained from thoracocentesis had a creatinine level of 989 μmol/L and fluid creatinine:serum creatinine ratio of 1.6:1. These results are highly suggestive of both urinothorax and uroabdomen.

Discussion

Urinothorax is a rare cause of a pleural effusion following urinary tract trauma that is most commonly associated with a diaphragmatic structural deficit and has also recently been described without structural compromise to the diaphragm in a canine patient (Tsompanidou et al. 2015). Urinothorax can be confirmed by analysis of fluid obtained via thoracocentesis. In most cases the fluid has a low pH and low glucose concentration. Pleural fluid:serum creatinine ratio is expected to be >1:1 with some cases having ratios >10:1 (Ranjan et al. 2015). The pleural

Companion Animal Society Newsletter

Volume 27 Number 1

fluid: serum creatinine ratios have been adapted for veterinary patients from human literature (Laskaridis et al. 2012; Ranjan et al. 2015). In human medicine a definitive diagnosis of uroabdomen can be made if at least two of the following criteria are met (S. Klainbart 2011): (1) Abdominal fluid creatinine concentration:serum creatinine concentration ratio >2:1 (2) Abdominal fluid creatinine >4-fold the upper limit of the serum reference range (3) The ratio of abdominal fluid potassium to serum potassium is greater than 1.4:1 This method has been validated in canine patients by Schmiedt et al. in their 2001 study, which included 13 dogs affected by uroabdomen with 8 control animals. Schmiedt et al. 2001 identified criterion (1) to have a sensitivity of 100% and specificity of 86%. When criterion (2) was evaluated, all of the dogs in their study with a uroabdomen had an abdominal fluid creatinine concentration that was at least 4-fold the serum reference range. Criterion (3) was identified to have 100% sensitivity and specificity. If two of these criteria were met, the sensitivity and specificity for diagnosis of uroabdomen increased to 100% (Schmiedt et al. 2001). Similar methodology has been used in feline patients where an abdominal fluid potassium:serum potassium ratio of 1.9:1 and an abdominal fluid creatinine: serum creatinine ratio of >2:1 have been identified as useful indicators of uroabdomen (Aumann et al. 1998). Trauma is the most common cause of diaphragmatic herniation in canine and feline patients, comprising up to 85% of cases, with the remaining cases being typically iatrogenic or congenital/anatomical in origin. Feline patients most commonly have a circumferential diaphragmatic tear (59%) with fewer radial tears (18%) while in canine patients the orientation of tears is more evenly circumferential (40%) or radial (40%) (Tobias and Johnston 2012). The single most useful radiographic view for the diagnosis of diaphragmatic hernia is the lateral thoracic projection. Partial loss of the normal line of the diaphram is present in 66% to 97% of animals with a diaphragmatic hernia (Tobias and Johnston 2012), thus a normal radiographic appearance does not always rule out structural compromise. A number of imaging modalities can be utilized to investigate the integrity of the bladder wall and associated urinary tract structures. Initial imaging may include abdominal ultrasound and orthoganol plain radiographic views. If bladder integrity remains in doubt, rupture of the bladder and other urinary trauma can be confirmed with a high level of sensitivity using positive contrast radiographic techniques where extravasation of the contrast into the abdomen from the bladder, urethra &/or ureteral defect may be seen. On presentation of this case to Massey University further medical stabilization, including crystalloid fluid therapy, calcium gluconate and insulin administration to correct hyperkalemia, oxygen therapy and placement of a closed suction drain within the abdomen was performed prior to proceeding to surgery. The abdomen was surgically approached

March 2016

via a midline coeliotomy. A 2 cm circumferential ventrally orientated diaphragmatic tear was identified and closed using a simple continuous suture pattern. A rupture in the bladder wall was identified which had necrotic edges that required debridement prior to closure using a simple continuous suture pattern. A thoracic drain, abdominal drain and cystostomy tube were placed intraoperatively. This patient recovered over the following days without complication and communication with the owners four months later found the patient to be doing well.

Aknowledments

Dr Alanda Rafferty for the clinical history and radiographic image.

References

Aumann M, Worth LT, Drobatz KJ. Uroperitoneum in cats: 26 cases (1986-1995). Journal American Animal Hospital Association 34, 315–24, 1998 Schmiedt C, Tobias KM, Otto SM. Evaluation of Abdominal Fluid: Peripheral Blood Creatinine and Potassium Ratios for Diagnosis of Uroperitoneum in Dogs. Journal of Veterinary Emergency and Critical Care 11, 275–80, 2001 Connally HE. Cytology and fluid analysis of the acute abdomen. Clinical Techiques in Small Animal Practice 18, 39–44, 2003 Frank PM, Mahaffey MB. The Peritoneal Space. In: Thrall DE (ed). Textbook of Veterinary Diagnostic Radiology. Fifth Edtn. Pp 647–64. Saunders Elsevier, St. Louis, Missouri, USA, 2007 Klainbart S, Merchav R, Ohad DG. Traumatic urothorax in a dog: a case report. Journal of Small Animal Practice 52, 544– 6, 2011 Laskaridis L, Kampantais S, Toutziaris C, Chachopoulos B, Perdikis I, Tahmatzopoulos A, Dimitriadis G. Urinothorax – an underdiagnosed cause of acute dyspnea: report of a bilateral and of an ipsilateral urinothorax case. Case Report Emergency Medicine 2012, 395653, 2012 Nelson RW, Couto CG, Davidson AP, DiBartola SP, Hawkins EC, Lappin MR, Scott-Moncrieff JCR, Taylor SM, Ware WA, Watson PJ, Westropp JL, Willard MD. Disorders of the peritoneum. In: Small Animal Internal Medicine. Fifth Edition Edtn. Pp 492–6. Elsevier Mosby, Canada, 2014a Nelson RW, Couto CG, Davidson AP, DiBartola SP, Hawkins EC, Lappin MR, Scott-Moncrieff JCR, Taylor SM, Ware WA, Watson PJ, Westropp JL, Willard MD. Clinical Manifestations of the Pleural Cavity and Mediastinal Disease. In: Small Animal Internal Medicine. Fifth Edition Edtn. Pp 337–55. Elsevier Mosby, Canada, 2014b Ranjan V, Agrawal S, Chipde SS, Dosi R. Urinothorax: A path, less travelled: Case report and review of literature. Journal of Natural Science Biology and Medicine 6, 213–6, 2015 Stafford JR, Bartges JW. A clinical review of pathophysiology, diagnosis, and treatment of uroabdomen in the dog and cat. Journal of Veterinary Emergency and Critical Care (San Antonio) 23, 216–29, 2013 Thrall DE. The Pleural Space. In: Thrall DE (ed). Textbook of Veterinary Diagnostic Radiology. Fifth Edtn. Pp 555–67. Saunders Elsevier, St. Louis, Missouri, USA, 2007 Tobias KM, Johnston SA. Veterinary Surgery: Small Animal. 1st Edtn. Elsevier Saunders, St Louis, Missouri, USA, 2012 Tsompanidou PP, Anagnostou TL, Kazakos GM, Papazoglou LG, Flouraki ES, Patsikas MN. Urothorax Associated with Uroperitoneum in a Dog Without Diaphragmatic Disruption. Journal American Animal Hospital Association 51, 256–9, 2015

Companion Animal Society Newsletter

MASSEY

UNIVERSIT Y

TE KUNENGA KI PUR EHUROA

VETERINARY TEACHING HOSPITAL Buildings

Radiologist Dr. Bob Bahr, has returned to the USA after a very worthwhile seven-month locum. Dr. Bahr was a great asset in the imaging department, supporting Dr. Ron Green while Paul Wightman is away in Melbourne. Paola Giordano has re-joined us as an anaesthetist, on a permanent basis, having been a locum for us in 2015. We are currently advertising for a second resident in small animal nutrition, sponsored by Royal Canin, and rotating internships within the VTH. See the Massey website for details.

The new Wildbase hospital build is gaining pace with the erection of the concrete wall slabs and major structural elements: see photos accompanying this article. The temporary small animal reception and retail areas are working well with minimal inconvenience to clients. There may be some minor disruption to the consulting rooms later in the process as the “street” is created which will link the VTH, Wildbase and IVABS into one access point.

Services Novel surgical solutions Andrew Worth, Jonathan Bray and Kat Crosse have been pioneering the use of computeraided-design (CAD) and rapid-prototype manufacturing (also known as 3D printing) at the VTH. What started as a unique solution to an angular limb deformity in a toy breed dog, has flourished into projects that include lumbosacral stabilization with targeted drill insertion points and bone replacement/bridging in oncologic cases. Jonathan has used titanium scaffolds customized to replace sections of the mandible in animals with mandibular neoplasia as well as limb-sparing procedures of the fore and hindlimb. Kat and Andrew have continued to refine the use of 3D printed drill jigs to more accurately perform closing wedge osteotomies as well as the installation of titanium scaffolds in an open wedge, preventing loss of limb length. They have set-up a website portal to access these technologies: iO surgical solutions – http://www. ioss.co.nz

People

Richard Burchell has joined the MUVTH and which brings the small animal medicine team back to full strength following Els Acke’s decision to remain in Europe raising her new family. Richard’s professional background includes an honours degree in Microbiology (Rhodes University) and a BVSc from the University of Pretoria. He is a diplomate of the European College of Veterinary Internal Medicine and has been a Senior Lecturer and a specialist veterinarian in private practice in South Africa. He has settled in famously and is a real asset to the team. He is looking forward to managing the many challenging referral cases provided by our patrons. Having completed her residency, Kat Crosse has been offered a permanent faculty position in Small Animal Surgery. Kat has become a pivotal part of the surgery team and we will all welcome her appointment. Once her European Boards examinations are completed she will be embarking on a PhD into Brachycephalic Airway Syndrome as well as a consultant surgeon role in the VTH.

News...

Cardiology in 2016 Dr. Fiona Campbell (specialist cardiologist) will again join us on four occasions through this year. After graduating from the University of Queensland she worked in the United Kingdom and Australia for 2 years before undertaking a PhD. She completed a 3-year residency programme in all-species cardiology at the University of California, Davis and become a Diplomate of the American College of Veterinary Internal Medicine (Cardiology) in 2006. Fiona will be consulting on referral cases, teaching undergraduates and performing interventional radiology procedures. Boehringer Ingelheim are sponsoring Fiona’s trips to NZ. On her last visit Fiona successfully treated two congenital cardiac anomalies with minimally invasive stenting techniques. Having access to this type of cutting edge technology and expertise is a great opportunity for your clients. We will be advising our patrons of the dates for Fiona’s visits.

Companion Animal Society Newsletter

Volume 27 Number 1

Subject Index: Volume 26: 2015 Issue Pages number Alastair Coomer Specialist Profile

34–36

Anxiety and pain in companion animals in the clinic

18–22

Book review – Kirks Current Vet Therapy XV

42–43

Canine Atopic Dermatitis – evaluation of pruritus and lesions

32–34

Conference report: ECVIM Companion Animal Conference 2014

45–47

Conference report: North American Vet Dental Forum 2015

36–37

Conference report: WSAVA Congress 2015

38–39

Dentigerous Cysts: case report

20–25

ECVIM Companion Animal Conference 2014

45–47

Extraction complications and how to avoid them

22–30

Feline Leukaemia Virus

38–40

Feline paraneoplastic alopecia – role of path in diagnosis

Femoral Salter Harris Type 1 fracture – What is your diagnosis?

10/44

Gastrointestinal conditions – use of ultrasound for diagnosis

26–30

Haemangiosarcoma in dogs

12–18

Hemivertebra in dogs

14–16

Insulinoma-induced hypoglycemia – medical management

32–36

Intraocular prostheses

28–30

Kirks Current Vet Therapy XV book review

42–43

Lateral condylar fracture in a puppy – case study

32–38

Hannah Bain

Katherine Reid

Chris Welland and Duncan Graham Duncan Graham Pru Galloway

Duncan Graham David Smith

Craig Hunger Pru Galloway

Craig Hunger Pru Galloway Geoff Orbell

Kevin Frame Kate Heller

Deepti Deshpande and Boyd Jones Boyd Jones Neil Stuttle

Craig Irving

Chris Welland and Duncan Graham Karina Wilde

March 2016

Companion Animal Society Newsletter

Mouth gags – can use cause neurological damage

32–33

Necrotising fasciitis – role of path in diagnosis

36–37

North American Vet Dental Forum 2015 – conference report

36–37

Pancreatitis – diagnosis of

12–15

Practitioner on sabbatical 2014 report

Practitioner on sabbatical 2015 report

Peter Collinson – Specialist Profile

41–40

Pru Galloway – Specialist Profile

Rabbit jaw abcesses – treatment options

24–26

Rubber jaw syndrome in a CKC spaniel

16–20

Specialist Profile – Alastair Coomer

34–36

Specialist Profile – Pru Galloway

Specialist Profile – Peter Collinson

40–41

Traumatic brain injury in a cat

20–26

Ultrasound– review of use for GIT conditions in small animals

26–30

Unusual dermatological conditions – role of pathology (Part 2: necrotizing fasciitis)

36–37

Mike Gieseg Geoff Orbell

Duncan Graham Boyd Jones Kate Heller

Karina Wilde

Hannah Bain Hannah Bain

Brendon Bullen Judith Visser Hannah Bain Hannah Bain Hannah Bain

Tania Krupitza Kate Heller

Geoff Orbell

Unusual dermatological conditions – role of pathology (Part 3: Feline paraneoplastic alopecia 4

Urinary bladder mass – What is your diagnosis?

10/46

Warfare – history of dogs in war

12–18

What is your diagnosis? Urinary bladder mass

10/46

What is your diagnosis? Femoral Salter Harris Type 1 Fracture

10/44

WSAVA Congress 2015 – conference report

38–39

Volume 27 Number 1

Geoff Orbell

Barry Hedgespeth Boyd Jones

Barry Hedgespeth Kevin Frame David Smith

Companion Animal Society Newsletter

NZVA COMPANION ANIMAL SOCIETY NEWSLETTER

New Zealand Veterinary Association

Companion Animal Society Volume 27 No 1 March 2016

In This Issue ...

VOLUME 27 NO 1 MARCH 2016