Notes on Small Animal Dermatology

377 Pages·2010·5.449 MB·English

by  Judith Joyce

NOTES ON SMALL ANIMAL DERMATOLOGY

NOTES ON SMALL ANIMAL
DERMATOLOGY
Judith Joyce
This edition fi rst published 2010
© 2010 Judith Joyce
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Library of Congress Cataloging-in-Publication Data
Joyce, Judith.
Notes on small animal dermatology / Judith Joyce.
p.; cm.
Includes index.
ISBN 978-1-4051-3497-2 (pbk. : alk. paper)
1. Veterinary dermatology—Handbooks, manuals, etc. 2. Pet medicine—Handbooks, manuals,
etc. I. Title. II. Title: Small animal dermatology.
[DNLM: 1. Skin Diseases—veterinary—Handbooks. 2. Animals, Domestic—Handbooks.
3. Skin Diseases—diagnosis—Handbooks. 4. Skin Diseases—therapy—Handbooks. SF 901 J89n
2010]
SF901.J69 2010
636.089'65—dc22
2009048319
A catalogue record for this book is available from the British Library.
Set in 9/11.5 pt Sabon by MPS Limited, A Macmillan Company, Chennai, India
Printed in Malaysia
1 2010
Contents
Section 1: The Basic Tools 1
Chapter 1
Terminology and Glossary 3
Chapter 2
Lesions 11
Chapter 3
Investigation and Diagnosis 20
3.1 History 20
3.2 Clinical examination 21
3.3 Examination for ectoparasites 25
3.4 Cytology 31
3.5 Skin biopsies 34
3.6 Fungal examination 38
3.7 Examinations for bacteria and yeasts 40
3.8 Allergy testing 41
3.9 Tests for endocrine disease 43
Section 2: Problem-Orientated Approach 47
Chapter 4
The Pruritic Patient 49
4.1 Causes of pruritus 49
4.2 The pruritic dog 50
4.3 The more mature patient 54
4.4 The pruritic cat 54
4.5 Clinical approach to the pruritic cat 60
Chapter 5
The Scaling Patient 65
5.1 The most common cause of scaling conditions is parasites 65
5.2 Localisation of scaling disorders 68
5.3 Dermatophytosis 68
5.4 Bacterial and yeast infections 68
5.5 Systemic disease 68
5.6 Endocrine disease 69
5.7 Mild scaling 69
5.8 Biopsy 70
5.9 Immune-mediated disease 70
vi Contents
5.10 Primary genetic scaling disorders 71
5.11 Hypersensitivity dermatitis 71
5.12 Treatment of scaling disorders 71
Chapter 6
The Alopecic Patient 72
6.1 Congenital or acquired hairloss 72
6.2 Pattern alopecias 72
6.3 Traumatic hairloss 72
6.4 Infl ammatory hairloss 73
6.5 Screen for alopecia due to systemic disease 75
6.6 Paraneoplastic alopecia 75
6.7 Endocrine alopecia 75
6.8 Biopsy 76
6.9 Non-endocrine alopecias 77
6.10 Long-term palliative treatment is usually necessary in alopecic skin
conditions to address secondary complications 77
Chapter 7
Management of Diseases Presenting with Spots (Papules, Pustules,
Vesicles and Bullae) 78
7.1 Young animals 78
7.2 Severe/recurrent or persistent lesions 80
7.3 Investigation of papular disease 81
7.4 Investigation of vesicular disease 81
7.5 Investigation of pustular disease 81
7.6 Folliculitis 83
Chapter 8
Approach to Changes in Pigmentation 85
8.1 Changes in pigmentation may be generalised or may be localised
in specifi c patterns 85
8.2 Secondary changes in pigmentation should be differentiated from
primary changes 85
8.3 Generalised hyperpigmentation may occur in some endocrine and
non-endocrine conditions 85
8.4 Pigmentary change may be benign and/or transient 87
8.5 Loss of pigmentation of the skin 87
8.6 Reddening of the skin 87
8.7 Increase in pigmentation 88
8.8 Loss of pigmentation of hair coat 88
8.9 Early histopathological examination is essential 88
8.10 Some lesions cannot always be defi nitively diagnosed on biopsy 89
Contents vii
Chapter 9
Management of Raised and Ulcerative Skin Lesions 90
9.1 Papular pustular and vesicular disease 90
9.2 Eosinophilic granuloma complex 90
9.3 Cytology or histopathology 90
9.4 Treatment of neoplastic disease 92
9.5 Raised lesions due to micro-organisms 92
9.6 Defi nitive diagnosis reached 92
9.7 Chronic infl ammatory and bacteria/fungal lesions 93
Section 3: Aetiological Approach 95
Chapter 10
Diseases Caused by Ectoparasites 97
10.1 Dog 97
10.2 Cats 109
10.3 Rabbit 114
10.4 Guinea pigs 118
10.5 Other mites and lice of rabbits, mice and gerbils 120
Chapter 11
Skin Disease Caused by Micro-organisms 121
11.1 Bacterial infections 121
11.2 Leishmaniosis 128
11.3 Fungal infections 129
11.4 Malassezia dermatitis 134
11.5 Skin diseases caused by viruses 136
Chapter 12
Hypersensitivity Dermatitis 138
12.1 Parasitic hypersensitivity 138
12.2 Atopic dermatitis 140
12.3 Adverse cutaneous reaction to food 143
12.4 Insect bite hypersensitivity 149
12.5 Bacterial, fungal and yeast hypersensitivity 150
Chapter 13
Management of Immune-Mediated Disease 152
13.1 Types of immune-mediated disease 152
13.2 The management of immune-mediated disease 152
13.3 Specifi c diseases 156
viii Contents
Chapter 14
Endocrine Disease 163
14.1 Hyperadrenocorticism 163
14.2 Hypothyroidism 167
14.3 Less common endocrine diseases with a primary effect on
the skin 171
14.4 Common endocrine diseases that have a secondary effect on
the skin 174
14.5 Rare endocrine problems 175
Chapter 15
Disorders of the Pilosebaceous Unit (Hair Follicle Disorders) 176
15.1 Primary hair follicle dysplasias 176
15.2 Secondary hair follicle dysplasias 178
Chapter 16
Neoplastic Skin Disease 180
16.1 Primary skin masses 180
16.2 Common types of skin neoplasia 183
16.3 Generalised skin neoplasia 185
16.4 Metastatic skin neoplasia 186
16.5 Paraneoplastic syndromes 186
Chapter 17
Other Skin Diseases 188
17.1 Metabolic disease 188
17.2 Nutritional disease 189
17.3 Environmental causes 190
17.4 Psychogenic dermatoses 191
17.5 Dermatoses of neurological origin 191
Section 4: Anatomically Localised Skin Disease 193
Chapter 18
The Foot 195
18.1 Management of claw disease 195
18.2 Management of footpad disease 201
18.3 Pododermatitis 204
Chapter 19
Skin Disease Affecting the Perianal Region 210
19.1 Management of perianal skin disease 210