Critically appraised topic on adverse food reactions..: duration of elimination diets

Olivry et al. BMC Veterinary Research (2015) 11:225 DOI 10.1186/s12917-015-0541-3

RESEARCH ARTICLE

Open Access

Critically appraised topic on adverse food reactions of companion animals (1): duration of elimination diets Thierry Olivry1*, Ralf S. Mueller2 and Pascal Prélaud3 Abstract Background: Restrictive (i.e. elimination)-provocation dietary trials remain the standard of care to diagnose cutaneous adverse food reactions (CAFRs) in dogs and cats. There is currently no consensus on the duration of elimination diet trials that would permit the highest sensitivity of diagnosis of CAFR in companion animals.

Results: The search for, and review and analysis of the best evidence available as of December 14, 2014 suggests that, by 5 weeks in dogs and 6 weeks in cats after starting an elimination diet, more than 80 % of patients had achieved a remission of clinical signs of CAFR. Increasing the diet trial duration to 8 weeks leads to a complete remission in more than 90 % of dogs and cats with CAFR. Conclusions: For diagnosing CAFRs in more than 90 % of dogs and cats, elimination diet trials should last at least 8 weeks.

Keywords: Allergy, Atopic dermatitis, Canine, Cat, Dog, Elimination diet, Feline, Food allergy, Itch, Pruritus

Background The current standard for the diagnosis of cutaneous adverse food reactions (CAFRs) in dogs and cats involves the performance of dietary restriction-provocation tests. Over time, the recommendations for optimal duration of restrictive dietary trials (i.e. “elimination diets”) have varied from 3 to 12 weeks; there is currently no consensus on the duration of such trials for optimal diagnosis of CAFRs. Clinical scenario

Your patient is a 2-year-old male castrated German shepherd dog that is very itchy. On examination, you notice erythematous macules, patches and papules on the abdomen, axillae and the perineum; it also suffers from intermittent diarrhea. As this dog is already on an optimized flea control regimen, you suspect that food reactions cause all these signs. You would like to perform an elimination dietary trial to confirm this. You wonder how long this elimination diet should last. * Correspondence: tolivry@ncsu.edu 1 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27607, USA Full list of author information is available at the end of the article

Structured question

In dogs and cats suspected of having a CAFR, how long should an elimination diet trial last for highest sensitivity of diagnosis?

Search strategy

The CAB Abstracts and Web of Science (Science Citation Index Expanded) databases were searched on December 16, 2014, using the following string: ((dog or dogs or canine) or (cat or cats or feline)) and (food or diet*) and (reaction or allerg* or hypersensitivity) and (trial or restriction or elimination) and (skin or cutaneous or itch or pruritus). We limited the search to 25 years (1980 to 2014) and we excluded congress proceedings notes and book chapters.

Identified evidence

Our literature search identified 108 and 78 citations in the CAB Abstract and Web of Science databases, respectively; 45 articles were common to both databases.

Abstracts were read and pertinent articles were read in full. Two types of original articles provided data relevant to the question of interest: these articles either reported large case series of dogs or cats with CAFRs or the effect

© 2015 Olivry et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

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Fig. 1 Cumulative percentages of clinical remission in 209 dogs with CAFRs over time (in weeks)

of feeding one or more test diets to companion animals with CAFRs. Among these papers, five [1–5] and three [1, 3, 6] respectively provided specific data on the time needed for manifestations of CAFR to improve in dogs and cats fed a restrictive diet.

Evaluation of evidence

In the selected articles, the diagnosis of CAFR was generally made in dogs and cats with nonseasonal pruritus

after the exclusion of other relevant causes of pruritus and a complete or marked (at least 50 %) reduction of clinical signs after feeding a restrictive (elimination) diet, the latter consisting of novel or partially hydrolyzed ingredients. Cases with partial reduction of itch were then confirmed as having CAFR after recurrence of signs after provocation with previous diets or ingredients.

The cumulative percentages of complete, or near complete, remission of clinical signs of CAFR in dogs

Fig. 2 Cumulative percentages of clinical remission in 40 cats with CAFRs over time (in weeks)

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Olivry et al. BMC Veterinary Research (2015) 11:225

fed a restrictive diet are depicted on Fig. 1. Based on the information gathered from 209 dogs with CAFR, we can estimate that, after 3 weeks of a diet change, approximately half of dogs had achieved a marked reduction of their signs. From 5 weeks onward, signs had returned to normal in more than 85 % of dogs, and this percentage increased to over 95 % if extending the dietary trial to 8 weeks. Fewer than 5 % of dogs needed an elimination diet of up to 13 weeks for a complete remission of signs of CAFR to occur.

Cumulative percentages of clinical sign remission in 40 cats with CAFR are illustrated on Fig. 2. It took approximately 4, 6 and 8 weeks of a restriction diet for 50, 80 and 90 % of cats to achieve a remission of their clinical signs, respectively.

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References 1. Carlotti DN, Remy I, Prost C. Food allergy in dogs and cats. A review and report of 43 cases. Vet Dermatol. 1990;1:55–62.

2. Rosser EJ. Diagnosis of food allergy in dogs. J Amer Vet Med Assoc.

1993;203:259–62.

3. Denis S, Paradis M. L'allergie alimentaire chez le chien et le chat. 2. Etude rétrospective (food allergy in dogs and cats. 2. retrospective study). Méd Vét Québec. 1994;24:15–20.

4. Paterson S. Food hypersensitivity in 20 dogs with skin and gastrointestinal signs. J Small Anim Pract. 1995;36:529–34.

5. Loeffler A, Soares-Magalhaes R, Bond R, Lloyd DH. A retrospective analysis of case series using home-prepared and chicken hydrolysate diets in the diagnosis of adverse food reactions in 181 pruritic dogs. Vet Dermatol.

2006;17:273–9.

6. Guaguère E. Intolérance alimentaire à manifestations cutanées: a propos de 17 cas chez le chat [cutaneous adverse food reactions: 17 cases in cats].

Prat Med Chir Anim Comp. 1993;28:451–60.

Conclusion and implication for practitioners

To diagnose CAFR in at least 80 % of dogs and cats, a restrictive (elimination) dietary trial should last a minimum of 5 weeks in dogs and 6 weeks in cats. Increasing the duration of the restrictive diet to 8 weeks will increase the sensitivity of diagnosis to more than 90 % of cases in both species.

The ultimate goal of an elimination diet is to enable the positive confirmation of a CAFR with a provocation with suspected food items. As a result, veterinarians might elect to perform provocation tests soon after a remission of signs is achieved in a patient, even if such remission were to happen before 8 weeks after starting the elimination diet.

Abbreviations CAFR: Cutaneous adverse food reaction; CAT: Critically-appraised topic.

Competing interests In the past three years, the three authors have lectured for, and received research funding and/or consulting honoraria from Royal Canin (Aimargues, France), which paid publication charges for this article.

Authors’ contributions The three authors selected the topic of this CAT. TO performed the literature search, extracted and summarized the evidence and wrote this article. RSM and PP verified the evidence and edited the manuscript. All three authors read and approved the final manuscript.

Acknowledgements The authors thank Drs. Philippe Marniquet, Isabelle Mougeot and Sara Soler from Royal Canin for the initiation and support of this forthcoming series of critically appraised topics on adverse food reactions, and for paying publication charges for this article.

Author details 1 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27607, USA. 2 Medizinische Kleintierklinik, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University, Veterinärstrasse 13, 80539 Munich, Germany. 3Clinique Advetia, 5 rue Dubrunfaut, 75012 Paris, France.

Received: 18 May 2015 Accepted: 12 August 2015

CAT RC-CAT 1_duration 1_duration of elimination of elimination trial_BMC trial_BMC Vet Vet ResRes 2015.indd 2015-4P-A4.indd 3 3

Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit

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mum of 5 weeks in dogs and 6 weeks in cats. Increasing the duration of the restrictive diet to 8 weeks will increase the sensitivity of diagnosis to more than 90 % of cases in both species.

The ultimate goal of an elimination diet is to enable the positive confirmation of a CAFR with a provocation with suspected food items. As a result, veterinarians might elect to perform provocation tests (2015) soon 11:225 after a remission of Olivry et al. BMC Veterinary Research signs is achieved in a patient, even if such remission were to happen before 8 weeks after starting the elimination diet.

Abbreviations fed a restrictive diet are depicted on Fig. 1. Based on the CAFR: Cutaneous gathered adverse foodfrom reaction; CAT: Critically-appraised topic. information 209 dogs with CAFR, we can

estimate that, after 3 weeks of a diet change, approxiCompeting interests mately dogs had authors achieved marked reduction In the pasthalf threeof years, the three have alectured for, and received of their signs. weeks honoraria onward,from signs returned research fundingFrom and/or5consulting Royalhad Canin (Aimargues,to France), paid publication this article. normalwhich in more than 85charges % offordogs, and this percentage increased to over 95 % if extending the dietary trial to Authors’ contributions 8 weeks. Fewer than 5 % of dogs needed an elimination The three authors selected the topic of this CAT. TO performed the literature diet ofextracted up to and 13 summarized weeks forthea evidence complete of signs search, and remission wrote this article.

RSM and PP verified evidence and edited the manuscript. All three authors of CAFR to the occur. read and approved the final manuscript.

Cumulative percentages of clinical sign remission in 40 cats with CAFR are illustrated on Fig. 2. It took apAcknowledgements proximately 6 and 8 Marniquet, weeks ofIsabelle a restriction diet for 50, The authors thank4,Drs. Philippe Mougeot and Sara Soler from Royal Canin the cats initiation support ofa this forthcomingof series of 80 and 90 %for of toand achieve remission their critically appraised topics on adverse food reactions, and for paying clinical signs, respectively. publication charges for this article.

Author details Conclusion and implication for practitioners 1 Department of Clinical Sciences, College of Veterinary Medicine, North To diagnose CAFR1060 in William at least 80Drive, % ofRaleigh, dogsNCand cats, Carolina State University, Moore 27607, USA.a 2 Medizinische Kleintierklinik, Centre for Clinical Veterinary Medicine, restrictive (elimination) dietary trial should last 3aLudwig miniMaximilian University, Veterinärstrasse 13, 80539 Munich, Germany. Clinique mum of 5 weeks in dogs and 6 weeks in cats. Increasing Advetia, 5 rue Dubrunfaut, 75012 Paris, France.

the duration of the restrictive diet to 8 weeks will inReceived:the 18 May 2015 Accepted: 12 August 2015 crease sensitivity of diagnosis to more than 90 % of cases in both species.

The ultimate goal of an elimination diet is to enable the positive confirmation of a CAFR with a provocation with suspected food items. As a result, veterinarians might elect to perform provocation tests soon after a remission of signs is achieved in a patient, even if such remission were to happen before 8 weeks after starting the elimination diet.

CAT 1_duration of elimination trial_BMC Vet Res 2015.indd 3

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References 1. Carlotti DN, Remy I, Prost C. Food allergy in dogs and cats. A review and report of 43 cases. Vet Dermatol. 1990;1:55–62.

2. Rosser EJ. Diagnosis of food allergy in dogs. J Amer Vet Med Assoc.

1993;203:259–62.

3. Denis S, Paradis M. L'allergie alimentaire chez le chien et le chat. 2. Etude rétrospective (food allergy in dogs and cats. 2. retrospective study). Méd Vét Québec. 1994;24:15–20.

4. Paterson S. Food hypersensitivity in 20 dogs with skin and gastrointestinal signs. J Small Anim Pract. 1995;36:529–34.

5. Loeffler A, Soares-Magalhaes R, Bond R, Lloyd DH. A retrospective analysis of case series using home-prepared and chicken hydrolysate diets in the diagnosis of adverse food reactions in 181 pruritic dogs. Vet Dermatol.

2006;17:273–9.

6. Guaguère E. Intolérance alimentaire à manifestations cutanées: a propos de 17 cas chez le chat [cutaneous adverse food reactions: 17 cases in cats].

Prat Med Chir Anim next Comp. manuscript 1993;28:451–60. to BioMed Central Submit your

and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit

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Abbreviations CAFR: Cutaneous adverse food reaction; CAT: Critically-appraised topic.

Competing interests In the past three years, the three authors have lectured for, and received research funding and/or consulting honoraria from Royal Canin (Aimargues, France), which paid publication charges for this article.

Authors’ contributions The three authors selected the topic of this CAT. TO performed the literature search, extracted and summarized the evidence and wrote this article. RSM and PP verified the evidence and edited the manuscript. All three authors read and approved the final manuscript.

Acknowledgements The authors thank Drs. Philippe Marniquet, Isabelle Mougeot and Sara Soler from Royal Canin for the initiation and support of this forthcoming series of critically appraised topics on adverse food reactions, and for paying publication charges for this article.

Author details 1 Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27607, USA. 2 Medizinische Kleintierklinik, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University, Veterinärstrasse 13, 80539 Munich, Germany. 3Clinique Advetia, 5 rue Dubrunfaut, 75012 Paris, France.

Received: 18 May 2015 Accepted: 12 August 2015

CAT RC-CAT 1_duration 1_duration of elimination of elimination trial_BMC trial_BMC Vet Vet ResRes 2015.indd 2015-4P-A4.indd 3 4

Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit

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