Exam 2: Immunologic Skin Diseases Flashcards
What do hypersensitivity/allergic dermatoses look like histologically?
Eosinophilic and mastocytic perivascular dermatitis with dermal edema
+ changes associated with self trauma due to severe pruritus
+/- changes associated with secondary infections
What lesions are associated with atopic dermatitis?
Pruritic
Skin lesions generally secondary to self trauma
Erythema, wheal, alopecia, excoriation, salivary staining
Chronic = lichenification, hyperpigmentation
What is the lesion distribution of atopic dermatitis?
Face, paws, caudal carpi, distal extremities, ear, and ventrum
What are the primary and lesions associated with food allergy?
Primary lesions generally not present = erythema, papules, and wheals
What is the distribution of food allergy?
Same as atophic dermatitis
Face, paws, caudal carpi, distal extremities, ear, and ventrum
What are the primary lesions of flea allergy?
Crusted papules, somehwat bilaterally symmetrical pattern
What is the distribution of flea allergy?
Caudal half of animal
Dorsal lumbosacral region, tail base, perineum, and medial thighs
Lesions & Distribution: Feline Eosinophilic Plaque
Raised eythematous plaques
Ventral abdomen, perineum, and medial thigh
Lesions & Distribution: Feline Eosinophilic Granuloma
Papular, nodular or linear lesions on skin, mucocutaneous junctions, pawpads, oral cavity
Lesions & Distribution: Indolent Ulcer
Ulcerated lesion on upper lip (unilateral or bilateral)
Lesions & Distribution: Equine Eosinophilic Nodular Disease
Single or multple cutaneous papules or nodules (withers, neck, back, other sites)
Eosinophilic granulomas
What is the mechanism of acantholysis caused by pemphigus complex?
Group of immune-mediated diseases assocaited with formation of pustules and vesicles
Abs target keratinocytes cell-cell adhesion complexes (desmosomes) –> cleavage of desmosomes results in loss of cell-cell adhesion = ACANTHOLYSIS
What does acantholysis caused by pemphigus complex look like histologically?
Subcorneal pustule with acantholytic keratinocytes
What lesions are associated with acantholysis caused by pemphigus complex?
Pustules and vesicles
Erosions, crusts, scales
What is the distribution of acantholysis caused by pemphigus complex?
Dogs = bridge of nose, around eyes and pinnae
Cats = nail beds and face
Horses = face and distal extremities
Footpad keratosis can be only lesion in some dogs and cats
What are the gross lesions associated with discoid lupus erythematous?
Nasal planum = depigmentation, erythema, scaling, loss of “cobblestone” appearance
Dorsal muzzle, lips, perioral, and ears
Lesions exacerbated by UV light
