Flashcards in Lab Dermatopathology Class Deck (15):
refers to diseases of the integumentary system specifically affecting the skin, nails, hair, and glands
Basis of Urticaria
Mast cells degranulate resulting in microvascular hyperpermeability. Clinically presents with wheals which are usually puritic
disease of skin and mucous membranes that resembles lichen, ii. The most common CUTANEOUS presentation is as a well-defined area of purple-colored, itchy, flat-topped papules with interspersed lacy white lines
What type of hypersensitivity is contact dermatitis?
Type IV - CD4+ TH1 cells secrete cytokines that stimulate inflammation and activate phagocytes, leading to tissue injury
Acute form of contact dermatitis
diffuse erythema, edema, oozing, and crusting with formations of vesicles and bulla
Chronic form of contact dermatitis
Scaling, thickening skin
What hypersensitivity reaction is Pemphigus Vulgaris?
autoantibodies react against cell adhesion molecules causing acantholysis (loss of intercellular connections) of the epidermis and different mucosae.
Symptoms of Pemphigus Vulgaris
PV usually starts as oral lesions that make it difficult to eat (odynophagia). This may lead to noticeable weight
loss. Oral lesions are followed by generalized bullae 6-12 months later
Separation of the epidermis upon manual stretching of the skin. Lifting the skin results in separation from the dermis
5. How does the mechanism of blister formation in bullous pemphigoid differ from pemphigus vulgaris?
In bullous pemphigoid the antibody reaction is against hemidesmosomes rather than desmosomes; and it targets skin rather than mucosa
What condition involves CD+8 T cell toxicity along with keratinocyte injury?
keratinized cells with abnormal retention of nuclei at the stratum corneum