Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 28-year-old woman develops severe blistering and erosions of the skin and mucous membranes after sun exposure. Histopathology shows suprabasal acantholysis with IgG deposits along the intercellular spaces of the epidermis on immunofluorescence. Serum contains autoantibodies against desmogleins 1 and 3. Which of the following best describes the pathologic mechanism of blister formation?
Answer choices
- AImmune complex deposition at the dermal-epidermal junction
- BComplement-independent neutrophil infiltration causing subcorneal abscess formation
- CAntibody-mediated disruption of cell-to-cell adhesion (Type II hypersensitivity)Correct answer
- DMast cell degranulation triggering local edema and blister formation
- EDelayed-type cellular immune response with keratinocyte apoptosis
- FSerum sickness-like reaction with circulating immune complex formation at the basement membrane zone
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