BRITISH VETERINARY DERMATOLOGY STUDY GROUP AUTUMN MEETING l NOVEMBER 2012 Feline Dermatology .................................................................................................................. Radisson SAS Manchester Sat 10th / Sun 11th November 2012 AUTUMN PROCEEDINGS 2012Proceedings sponsored by BRITISH VETERINARY DERMATOLOGY STUDY GROUP AUTUMN MEETING Radisson SAS Manchester Sat 10th / Sun 11th November 2012 Sponsors Diamond: Virbac Pearl: Dechra Veterinary Products Pfizer Platinum: Dechra Laboratory Services Elanco Novartis Gold: ALK-Abelló (Formerly Artu) Bayer IDEXX Royal Canin Vetruus Silver: Dermoscent®; made in France by LDCA and distributed in the UK by Vet Direct The B.V.D.S.G. committee and members would like to thank our sponsors for their generosity and support of this meeting Proceedings designed and printed by Taproom Images for the British Veterinary Dermatology Study Group. Proceedings Editor: Sarah Warren BVetMed MSc (Clin. Onc.) CertVD MRCVS, Regional Veterinary Dermatologist, CVS. Mildmay Veterinary Centre, Winchester Tel: 01962 854088 Fax: 01962 870844 E: [email protected] © British Veterinary Dermatology Study Group. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, photocopying, electronic, mechanical, recording or otherwise, without the prior permission of British Veterinary Dermatology Study Group. 1 BVDSG Autumn Meeting – November 2012 Feline Dermatology Programme Saturday 10th November 2012 MORNING SESSION 0830 - 0900 Registration 0900 - 0945 Feline reaction patterns - cats are not small dogs Craig Griffin 0945 - 1030 Fleas and other little critters: Ectoparasites in cats Craig Griffin 1030 - 1115 COFFEE AND COMMERCIAL EXHIBITION 1115 - 1245 Breed related infections and oddities in cats Ross Bond 1245 - 1400 LUNCH AFTERNOON SESSION 1400 - 1445 Feline Mycobacterial diseases Danièlle Gunn-Moore Speaker - Kerry Simpson 1445 - 1530 Feline Cowpox Virus and Upper Respiratory Tract diseases Danièlle Gunn-Moore Speaker - Kerry Simpson 1530 - 1615 COFFEE AND COMMERCIAL EXHIBITION 1615 - 1715 AGM 1800 - 1900 Drinks, dinner from 1900 2 BVDSG Autumn Meeting – November 2012 Feline Dermatology Programme continued Sunday 11th November 2012 MORNING SESSION 0900 - 0945 Allergic skin conditions Craig Griffin 0945 - 1030 Autoimmune skin diseases Craig Griffin 1030 - 1115 COFFEE AND COMMERCIAL EXHIBITION 1115 - 1200 Feline cutaneous bacteriology and pyoderma Anita Patel 1200 - 1245 Endocrine, paraneoplastic and dermatoses related to systemic disease Craig Griffin 1245 - 1400 LUNCH AFTERNOON SESSION 1400 - 1445 Neurology related skin diseases in the feline patient Claire Rusbridge 1445 - 1530 Abstracts 1530 - 1600 COFFEE AND COMMERCIAL EXHIBITION 1600 - 1645 Behavioural factors in feline dermatological disease Sarah Heath 3 CONTENTS Feline reaction patterns - cats are not small dogs 5 Craig Griffin Fleas and other little critters: Ectoparasites in cats 9 Craig Griffin Breed related infections and oddities in cats 15 Ross Bond Feline Mycobacterial diseases 25 Danièlle Gunn-Moore Feline Cowpox Virus 37 Danièlle Gunn-Moore Upper Respiratory Tract diseases 39 Danièlle Gunn-Moore Allergic skin conditions 55 Craig Griffin Autoimmune skin diseases 61 Craig Griffin Feline cutaneous bacteriology and pyoderma 65 Anita Patel Endocrine, paraneoplastic and dermatoses 73 related to systemic disease Craig Griffin Neurology related skin diseases in the feline patient 79 Claire Rusbridge Abstracts 85 Behavioural factors in feline dermatological disease 87 Sarah Heath 4 FELINE REACTION PATTERNS - CATS ARE NOT SMALL DOGS Craig E. Griffin, DVM, DACVD,Animal Dermatology Clinic, San Diego, California, USA www.animaldermatology.com A reaction pattern is the way the skin reacts to a specific insult or inflammation. This reaction pattern can occur on a gross or microscopic level. At the microscopic level this leads to the development of dermatopathologic interpretation based on pattern analysis. Each pattern is associated with a differential of common and less common causes. At the gross level this leads to clinical differentials.This is often based on the specific physical findings and the lesions that are clinically present. In cats there are a number of distinctive physical findings and lesions that can be associated with specific reaction patterns.There are also some conditions that have been given specific disease identities but are actually groups of lesions that can be associated with a variety of different diseases. Two examples of this include the eosinophilic granuloma complex and miliary dermatitis. Both have even been described as specific diseases but can consist of various types of lesions that are associated with a variety of underlying causes or specific diseases.For example, eosinophilic granuloma complex can present with three different clinical and histopathologic forms (upper lip ulcers, eosinophilic plaques and eosinophilic granulomas). This complex can be due to insect, dietary and environmental allergies, infectious agents, and genetic or hereditary factors. The hereditary mode of transmission was evaluated in a group of specific pathogen free cats.1 In this study 25 related cats with eosinophilic granuloma complex showed all forms of the disease and no underlying etiology could be detected suggesting an inherent metabolic abnormality or aberrant self-directed inflammatory response. Why these three lesions have been seen together is usually attributed to the underlying disease. However it may relate to something more basic; reaction patterns to pruritus. Another classic pattern in the cat is "barbered" alopecia which results from excessive licking.The licking can occur as a result of grooming behavior or from pruritus.This discussion will focus on barbered alopecia, eosinophilic plaques and lip ulcers which may share a similar underlying cause - pruritus and damage from the tongue - and lead to a common secondary problem, pyoderma. BARBERED ALOPECIA Barbered alopecia is when there is hair loss due to breaking of the hair (loss of hair length not hair growth) near the surface of the skin by licking. In some cases there may be areas with complete hair loss which reflects not just licking but the cat pulling the hair out. In these cases owners may note tufts of hair in the environment. Often the skin is not grossly inflamed though the excessive licking is still due to pruritus. Some cats will hide this grooming behavior and owners will not be aware of why the hair loss is occurring. Determining that the hair loss is from excessive licking is still simple.The skin may be rolled or folded and the margin examined for short stubbles or broken hairs which is relatively easy to visualize. It can also be detected by rubbing the skin with your fingers against the normal pattern of hair growth and feeling the broken hairs. There are two major causes of this type of alopecia. Most commonly the licking is in response to pruritus.The less common reason is the cat has developed excessive grooming behavior unrelated to any skin problem, referred to as psychogenic alopecia though the cat may also be licking due to deeper pain. An uncommon example of deep pain is when cats lick hair just off the abdomen in relation to cystitis. So the first goal in cats with barbered alopecia is to determine if the licking behavior is due to pruritus or not. One clue that indicates pruritus and not self grooming behavior is when the cat is pruritic in areas that it does not or cannot groom. In these situations the cat most likely scratches or rubs against objects. Scratching and even some rubbing may result in linear excoriations and ulcerations from the claws. Another clue is when there is inflammation in the skin. Though sometimes inflammation can result from the grooming it is associated more with pruritus. Another clue used to help is to try and determine if the cat has had other behavioral problems which raise the suspicion that the excessive grooming is also behavioral. One study of 21 cats that had been diagnosed and referred to a behaviorist for psychogenic dermatitis revealed that allergic skin disease was most often the cause.2 Food allergy was diagnosed in 12 (57%) with psychogenic dermatitis only likely in 2 cases. Once the barbered alopecia is determined to be from pruritus then allergic disease is the most likely cause with about 52% of non flea induced allergic cats likely having it.3 Though the author is not aware of any study this does not appear as common in allergic dogs. 5 LIP ULCERS Classic feline indolent ulcers initially occur on the upper lip near the median raphe or adjacent to the canine teeth. Initially there will be erosion and only with chronicity will a proliferative tissue response develop.This is an important distinction as some cases will have a swollen lip first that later ulcerates and that is a different problem. Lip ulcers not swelling are described as an early lesion when cats are experimentally induced to develop flea allergy dermatitis.4 This occurred in 5 of 8 cases and the histopathology of the early lip ulcer was neutrophilic with bacterial "colonization" in contrast to the allergy sites that were eosinophilic.This also fits the controversy that lip ulcers can vary their histopathologic findings from suppurative, eosinophilic to granulomatous. One case was presented where flea allergy likely induced a lip ulcer that then failed to respond to numerous treatments but eventually responded completely