Skin Diseases of the Dog and Cat (eBook)

Thelma Lee Gross DVM, Director, California Dematopathology Service, and Consultant, IDEXX Veterinary Services, West Sacramento, California Peter J. Ihrke VMD, Professor of Dermatology, Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis Emily J. Walder VMD, Director, propritor of An Independent Biopsy Service, Venice, California Verena K. Affolter DrMedVet, PhD, Associate Professor for Clinical Dermatopathology, University of California, Davis

SKIN DISEASES OF THE DOG AND CAT 3
Contents 9
SECTION ONE: INFLAMMATORY, DYSPLASTIC, AND DEGENERATIVE DISEASES 15
I DISEASES OF THE EPIDERMIS 17
1 Pustular Diseases of the Epidermis 18
Impetigo 18
Superficial spreading pyoderma 20
Candidiasis 23
Superficial pustular dermatophytosis 25
Pemphigus foliaceus 27
Pemphigus erythematosus 32
Subcorneal pustular dermatosis 33
Sterile pustular erythroderma of Miniature Schnauzers 34
Superficial pustular drug reactions 37
2 Bullous and Acantholytic Diseases of the Epidermis and the Dermal–Epidermal Junction 41
Bullous pemphigoid 41
Mucous membrane pemphigoid 44
Pemphigus vulgaris 46
Paraneoplastic pemphigus 50
Hereditary epidermolysis bullosa 52
Epidermolysis bullosa acquisita 54
Canine Darier’s disease 57
Linear IgA disease 59
3 Interface Diseases of the Dermal–Epidermal Junction 63
Ischemic dermatopathy/canine dermatomyositis 63
Discoid lupus erythematosus 66
Systemic lupus erythematosus 69
Pemphigus erythematosus 71
Exfoliative cutaneous lupus erythematosus of the German Shorthaired Pointer 73
Vesicular cutaneous lupus erythematosus of the Shetland Sheepdog and Collie 75
Erythema ab igne 77
Erythema multiforme 79
Feline thymoma-associated exfoliative dermatitis 82
Lupoid onychitis 84
4 Necrotizing Diseases of the Epidermis 89
Erythema multiforme 89
Feline thymoma-associated exfoliative dermatitis 92
Proliferative necrotizing otitis of kittens 93
Toxic epidermal necrolysis 94
Toxic shock syndrome of dogs 98
Superficial necrolytic dermatitis 100
Generic dog food dermatosis 105
Split pawpad disease 106
Burns 108
Irritant contact dermatitis 112
5 Spongiotic and Vesicular Diseases of the Epidermis 119
Allergic contact dermatitis 119
Feline eosinophilic plaque 123
Psoriasiform dermatitis of the pawpads 125
Facial dermatitis of Persian and Himalayan cats 126
6 Ulcerative and Crusting Diseases of the Epidermis 130
Pyotraumatic dermatitis 130
Feline allergic miliary dermatitis 132
Feline eosinophilic plaque 135
Feline mosquito bite hypersensitivity 136
Feline herpesvirus ulcerative dermatitis 138
Feline cowpox virus infection 141
Feline indolent ulcer 142
Feline idiopathic ulcerative dermatosis 144
Canine pyoderma gangrenosum 146
7 Hyperplastic Diseases of the Epidermis 150
Chronic hyperplastic dermatitis 150
Fibropruritic nodules 152
Acral lick dermatitis 154
Malassezia dermatitis 156
Hyperplastic dermatosis of the West Highland White Terrier 160
Actinic keratosis 162
Acanthosis nigricans of Dachshunds 165
Psoriasiform-lichenoid dermatosis 166
Lichenoid keratosis 168
Inflamed linear epidermal nevus 169
Giant cell dermatosis in FeLV-positive cats 171
8 Diseases with Abnormal Cornification 175
Primary seborrhea and seborrheic dermatitis 175
Vitamin A-responsive dermatosis 179
Canine ear margin seborrhea 181
Nasodigital hyperkeratosis 183
Nasal parakeratosis of Labrador Retrievers 184
Congenital follicular parakeratosis 186
Ichthyosis 188
Familial pawpad hyperkeratosis 193
Schnauzer comedo syndrome 195
Actinic comedones 197
Callus 198
Sebaceous adenitis 200
Zinc-responsive dermatosis 202
Superficial necrolytic dermatitis 205
Inflamed linear epidermal nevus 205
Acrodermatitis of Bull Terriers 207
PART II DISEASES OF THE DERMIS 213
9 Perivascular Diseases of the Dermis 214
Superficial spreading pyoderma 214
Atopic dermatitis 214
Food allergy 220
Canine flea allergy dermatitis 222
Feline allergic miliary dermatitis 225
Urticarial allergic eruption 226
Allergic contact dermatitis 228
Canine sarcoptic acariasis 230
Feline notoedric acariasis 233
Cheyletiellosis 234
Feline superficial demodicosis 236
Cutaneous microfilariasis 239
Hookworm dermatitis 242
Cutaneous anatrichosomiasis 243
Vitiligo 245
10 Vascular Diseases of the Dermis 252
Septic vasculitis 252
Urticaria and angioedema 253
Telangiectasia, phlebectasia, and cutaneous flushing 255
Cryoglobulinemia and cryofibrinogenemia 257
Neutrophilic immunologic vasculitis 258
Cell poor vasculitis 261
Familial cutaneous vasculopathy of German Shepherd Dogs 264
Vasculopathy of Greyhounds 265
Proliferative thrombovascular necrosis of the pinnae 267
Proliferative arteritis of the nasal philtrum 269
Solar vasculopathy 270
11 Lichenoid Diseases of the Dermis 275
Mucocutaneous pyoderma 275
Discoid lupus erythematosus 277
Pemphigus foliaceus 279
Vogt–Koyanagi–Harada-like syndrome 280
Psoriasiform-lichenoid dermatosis 283
Lichenoid keratosis 285
12 Infectious Nodular and Diffuse Granulomatous and Pyogranulomatous Diseases of the Dermis 286
Actinomycosis and nocardiosis 286
Bacterial pseudomycetoma 289
Feline leprosy syndrome 290
Canine leproid granuloma 295
Opportunistic mycobacterial infection caused by rapidly growing mycobacteria 297
Opportunistic mycobacterial infection caused by Mycobacterium avium complex 301
Dermatophytic pseudomycetoma 302
Cutaneous blastomycosis, histoplasmosis, and coccidioidomycosis 305
Cutaneous cryptococcosis 309
Sporotrichosis 312
Cutaneous infections of other opportunistic fungi 315
Cutaneous pythiosis, lagenidiosis, and entomophthoromycosis 317
Cutaneous protothecosis 323
Cutaneous leishmaniasis 326
13 Noninfectious Nodular and Diffuse Granulomatous and Pyogranulomatous Diseases of the Dermis 334
Sterile granuloma and pyogranuloma syndrome 334
Reactive histiocytosis 337
Juvenile sterile granulomatous dermatitis and lymphadenitis 341
Cutaneous xanthoma 344
Canine sarcoidosis 347
Foreign body reactions 348
Palisading granuloma 351
14 Nodular and Diffuse Diseases of the Dermis with Prominent Eosinophils, Neutrophils, or Plasma Cells 356
Arthropod bite reactions 356
Feline mosquito bite hypersensitivity 359
Spider bites 361
Fire ant bites 363
Feline herpesvirus ulcerative dermatitis 365
Feline eosinophilic plaque 366
Feline indolent ulcer 367
Feline eosinophilic granuloma 369
Canine eosinophilic granuloma 372
Canine eosinophilic dermatitis 374
Feline hypereosinophilic syndrome 376
Plasma cell pododermatitis 377
Familial cutaneous vasculopathy of German Shepherd Dogs 378
Canine sterile neutrophilic dermatosis (Sweet’s syndrome) 380
Sterile pustular erythroderma of Miniature Schnauzers 383
15 Degenerative, Dysplastic and Depositional Diseases of Dermal Connective Tissue 387
Calcinosis cutis 387
Calcinosis circumscripta 392
Cutaneous mucinosis 394
Cutaneous amyloidosis 397
Ehlers–Danlos syndrome 400
Feline acquired skin fragility syndrome 403
Topical corticosteroid reaction 406
Perforating dermatitis 408
Morphea 410
Cicatricial alopecia 411
Solar elastosis and fibrosis 413
PART III DISEASES OF THE ADNEXA 419
16 Pustular and Nodular Diseases without Adnexal Destruction 420
Superficial bacterial folliculitis 420
Feline dermatophytosis 424
Canine dermatophytosis 427
Pemphigus foliaceus 429
Sterile eosinophilic pustulosis 431
17 Pustular and Nodular Diseases with Adnexal Destruction 434
Deep bacterial folliculitis and furunculosis 434
German Shepherd Dog pyoderma 438
Postgrooming furunculosis 441
Acral lick dermatitis 443
Actinic furunculosis 443
Interdigital furunculosis 447
Callus pyoderma 447
Canine acne 449
Feline acne 451
Kerion 454
Canine demodicosis 456
Feline follicular demodicosis 461
Pelodera dermatitis 463
Sebaceous adenitis 467
Eosinophilic furunculosis of the face 464
18 Mural Diseases of the Hair Follicle 474
Alopecia areata 474
Mural folliculitis due to demodicosis and dermatophytosis 478
Pseudopelade 480
Eosinophilic mucinotic mural folliculitis in dogs 483
Degenerative mucinotic mural folliculitis in cats 486
Granulomatous mural folliculitis in dogs 488
Follicular mucinosis 491
19 Atrophic Diseases of the Adnexa 494
Hypothyroidism 495
Canine hyperglucocorticoidism 498
Feline hyperglucocorticoidism 501
Canine Sertoli cell tumor-associated skin disease 504
Canine female hyperestrogenism 506
Alopecia X 508
Postclipping alopecia 511
Feline paraneoplastic alopecia 512
Acquired pattern alopecia 515
Ischemic dermatopathy/canine dermatomyositis 517
Post-traumatic alopecia 519
Traction alopecia 521
Telogen effluvium 523
Doxorubicin-induced alopecia 524
Excessive physiological shedding 526
Feline psychogenic alopecia 527
20 Dysplastic Diseases of the Adnexa 532
Color dilution alopecia and black hair follicular dysplasia 532
Canine follicular dysplasia 536
Cyclical flank alopecia 539
Congenital hypotrichosis 542
Follicular lipidosis 544
Sebaceous gland hyperplasia 545
Sebaceous gland dysplasia 547
PART IV DISEASES OF THE PANNICULUS 551
21 Diseases of the Panniculus 552
Postrabies vaccination panniculitis 552
Postinjection panniculitis 555
Sterile abscess of repositol injection 556
Traumatic panniculitis 559
Vasculitic panniculitis of thermal burns 561
Idiopathic sterile nodular panniculitis 562
Vasculitic septal panniculitis 565
Feline pansteatitis 566
Metatarsal fistulation of the German Shepherd Dog 567
Pancreatic panniculitis 569
SECTION TWO: NEOPLASMS AND OTHER TUMORS 573
PART I EPITHELIAL NEOPLASMS AND OTHER TUMORS 575
22 Epidermal Tumors 576
Cutaneous horn of feline pawpad 576
Pawpad keratoma 576
Linear epidermal hamartoma 578
Dermoid cyst 580
Squamous papilloma 581
Viral papilloma 581
Canine pigmented viral plaque 585
Feline viral plaque 588
Actinic keratosis 589
Bowenoid in situ carcinoma 592
Squamous cell carcinoma 595
Basal cell carcinoma 603
Basosquamous carcinoma 611
23 Follicular Tumors 618
Follicular hamartoma 619
Fibroadnexal hamartoma 619
Follicular cyst 621
Dilated pore 626
Warty dyskeratoma 626
Trichofolliculoma 628
Trichoepithelioma 630
Infundibular keratinizing acanthoma 633
Tricholemmoma 635
Pilomatricoma 638
Trichoblastoma 639
Malignant trichoepithelioma 648
Malignant pilomatricoma 651
24 Sebaceous Tumors 655
Sebaceous duct cyst 655
Nodular sebaceous hyperplasia 655
Sebaceous hamartoma 657
Sebaceous nevus 657
Sebaceous adenoma 659
Sebaceous epithelioma 661
Sebaceous carcinoma 664
Nodular perianal gland hyperplasia and perianal gland adenoma 669
Perianal gland epithelioma 672
Perianal gland carcinoma 673
25 Sweat Gland Tumors 679
Apocrine cyst 680
Canine apocrine cystomatosis 681
Feline ceruminous cystomatosis 681
Apocrine cystadenoma 682
Apocrine secretory adenoma 684
Apocrine ductular adenoma 686
Apocrine secretory adenocarcinoma 691
Apocrine ductular carcinoma 695
Eccrine carcinoma 703
26 Nailbed Epithelial Tumors 709
Nailbed epithelial inclusion cyst 709
Nailbed inverted squamous papilloma 710
Nailbed keratoacanthoma 712
Nailbed squamous cell carcinoma 714
Nailbed basal cell carcinoma 716
Metastatic pulmonary carcinoma in cats 717
PART II MESENCHYMAL NEOPLASMS AND OTHER TUMORS 723
27 Fibrous Tumors 724
Collagenous hamartoma 724
Canine nodular dermatofibrosis 725
Acrochordon and acrochordonous plaque 727
Dermatofibroma 730
Nodular fasciitis 731
Fibroma 733
Canine keloidal fibroma 735
Fibrosarcoma 736
Myxoma 741
Myxosarcoma 742
Feline sarcoid 744
28 Vascular Tumors 749
Angiomatosis 749
Hemangioma 755
Lymphangiomatosis 762
Hemangiosarcoma 763
Lymphangiosarcoma 767
29 Perivascular Tumors 773
Glomus tumor 773
Hemangiopericytoma 776
30 Lipocytic Tumors 780
Lipomatosis 780
Lipoma 780
Spindle cell lipoma 784
Infiltrative lipoma 785
Liposarcoma 786
31 Smooth Muscle and Skeletal Muscle Tumors 792
Leiomyoma 792
Leiomyosarcoma 793
Canine skeletal muscle hamartoma 796
Rhabdomyosarcoma 797
32 Neural and Perineural Tumors 800
Traumatic neuroma 800
Merkel cell tumor 800
Benign peripheral nerve sheath tumor 803
Malignant peripheral nerve sheath tumor 806
33 Other Mesenchymal Tumors 811
Vaccine-induced sarcoma 811
Transmissible venereal tumor 814
Ganglion 817
Granular cell tumor 818
Anaplastic sarcoma with giant cells 820
34 Melanocytic Tumors 827
Lentigo 828
Melanocytoma 829
Melanocytoma–acanthoma 836
Melanoma 839
35 Histiocytic Tumors 851
Reactive fibrohistiocytic nodule 851
Canine cutaneous histiocytoma 854
Feline progressive dendritic cell histiocytosis 859
Histiocytic sarcoma 862
36 Mast Cell Tumors 867
Canine mast cell tumor 867
Feline mast cell tumor 872
Cutaneous mastocytosis 875
37 Lymphocytic Tumors 880
Cutaneous plasmacytoma 880
Cutaneous lymphocytosis 886
Epitheliotropic lymphoma 890
Nonepitheliotropic lymphoma 896
Chronic lymphocytic leukemia with cutaneous lesions 902
Index 909