|
|
(13 intermediate revisions by the same user not shown) |
Line 1: |
Line 1: |
− | {{review}}
| + | #REDIRECT[[:Category:Integumentary System - Pathology]] |
− | {{toplink
| |
− | |backcolour = FFCCCC
| |
− | |linkpage =Integumentary System - Pathology
| |
− | |linktext =Integumentary System
| |
− | |maplink = Integumentary System (Content Map) - Pathology
| |
− | |pagetype =Pathology
| |
− | }}
| |
− | <br>
| |
− | | |
− | ==Epidermal growth or differentiation disorders==
| |
− | | |
− | ===Seborrheic disease complex===
| |
− | *Abnormal cornification or function of sebaceous glands
| |
− | *Large amounts of free fatty acids and cholesterol
| |
− | *Decreased amounts of diester waxes in surface lipids
| |
− | *Bacterial population changes to pathogenic [[:Category:Staphylococcus species|coagulase positive staphylococci]]
| |
− | *Chronic disease affecting mainly dogs, sometimes cats and horses
| |
− | *Dry form - white to grey scales
| |
− | *Greasy form - scaly, excess brown to yellow lipids sticking to skin and hair
| |
− | | |
− | ===Primary idiopathic seborrhea===
| |
− | *Abnormal cornification
| |
− | *Epidermal turnover reduced to about 2/3 of normal
| |
− | *Microscopically:
| |
− | **Hyperkeratosis distending follicular ostia causing papillary appearance
| |
− | **Parakeratosis at edges of follicular ostia
| |
− | **Congested, oedematous dermal papillae
| |
− | **Spongiotic epidermis with leukocytes
| |
− | | |
− | ===Secondary seborrhea===
| |
− | *Develops secondarily to many types of disease (''e.g.'' [[Parasitic skin infections - Pathology|ectoparasites]], [[Mycotic skin infections - Pathology|fungal infections]], [[Endocrine effects on the skin - Pathology|endocrine disease]], internal disease or allergy)
| |
− | *Microscopically:
| |
− | **Hyperkeratosis and/or parakeratosis of follicles and epidermis
| |
− | **Lesions relevant to the other disease
| |
− | | |
− | ===Sebaceous adenitis===
| |
− | *Inflammation of sebaceous glands, alopecia, hyperkeratosis
| |
− | *Possibly immune-mediated
| |
− | *Mainly affects dogs
| |
− | **Long haired show multifocal, serpiginous and annular lesions
| |
− | *Microscopically:
| |
− | **Inflammation of sebaceous glands
| |
− | **Possibly orthokeratotic hyperkeratosis
| |
− | **Chronic lesions are deprived of sebaceous glands and contain mild inflammation and fibrosis at follicular isthmus
| |
− | | |
− | ==Pigmentation disorders==
| |
− | ===Hypopigmentation===
| |
− | *Leukoderma or vitiligo - loss of pigment in the skin
| |
− | *Leukotrichia - loss of pigment of the hair
| |
− | *Hypopigmentation or incomplete albinism - generalised reduction of pigment in skin or hair
| |
− | *Albinism - inherited lack of pigment
| |
− | *Dilution - reduced pigmentation
| |
− | *Can be localised or generalised, idiopathic or asociated with other diseases
| |
− | *Examples of hereditary conditions: Maltese dilution of cats, Chediak-Higashi syndrome, leukoderma and leukotrichia of Dobermans, Arabian fading syndrome
| |
− | *Asociated with some immune-mediated disorders, ''e.g.'' [[Skin Immunologic - Pathology#Lupus erythematosus|discoid lupus erythematosus]]
| |
− | | |
− | ===Hyperpigmentation===
| |
− | [http://w3.vet.cornell.edu/nst/nst.asp?Fun=Image&imgID=1782 Image of endocrine hyperpigmentation from Cornell Veterinary Medicine]
| |
− | *Results from irritation or inflammation, pigmented [[Skin Neoplastic - Pathology|neoplasms]] or [[Endocrine effects on the skin - Pathology|metabolic diseases]]
| |
− | *Lentigo - circumscribed macular or slightly raised plaque with epidermal hyperplasia and hyperpigmentation
| |
− | | |
− | ==Eosinophilic infiltration==
| |
− | ===Eosinophilic plaques===
| |
− | *Common in cats
| |
− | *Medial thighs and abdomen mostly involved
| |
− | *Often associated with hypersensitivity
| |
− | *Grossly:raised plaques, erythematous, pruritic, erosed or ulcerated
| |
− | *Microscopically: acanthosis, spongiosis, erosions or ulceration, predominantly eosinophilic dermatitis, possibly areas of collagen degeneration
| |
− | ===Eosinophilic granulomas===
| |
− | *Involves cats, dogs, horses
| |
− | *Collagen degeneration in lesions os eosinophil degranulation
| |
− | *Often involved in reaction to parasites, foreigh bodies or mas cell tumours
| |
− | *Grossly:
| |
− | **Papules, nodules, plaques, ulcers in skin
| |
− | **Nodules or ulcers in oral mucosa of cats and dogs or on foot pads of cats
| |
− | *Microscopically:
| |
− | **Nodular dermatitis or stomatitis
| |
− | **Fragments of degenerated collagen surrounded by eosinophils and macrophages
| |
− | | |
− | ===Eosinophilic folliculitis and furunculosis===
| |
− | *Rare in cats, dogs, cattle and horses
| |
− | *Possibly due to arthropod bites
| |
− | *May be multifocal in horses
| |
− | | |
− | ==Sterile granulomatous disorders==
| |
− | | |
− | ===Juvenile pyoderma===
| |
− | *Also known as '''Juvenile sterile granulomatous dermatitis and lymphadenitis, juveline cellulitis, puppy strangles'''
| |
− | *Involves dogs of less then 4 months of age
| |
− | *Grossly: pustular and nodular dermatitis with oedema involving the face, ears, mucocutaneous junctions
| |
− | *Microscopically: granulomatous or pyogranulomatous perifolliculitis, paniculitis and dermatitis
| |
− | | |
− | ===Equine generalised granulomatous disease===
| |
− | *Also known as '''Sarcoidosis'''
| |
− | *In horses
| |
− | *Rare
| |
− | *Involves cutaneous lesions and systemic disease causing anorexia and weight loss
| |
− | *Grossly: alopecia, scales, crusts, sometimes nodules and masses
| |
− | *Microscopically: multifocal granulomas, multinucleated giant cells
| |