A 30-year-old woman has recurrent flaccid pustules on the trunk and flexures with mild itching. Direct immunofluorescence shows intercellular IgA deposition. Histology reveals subcorneal pustules with minimal acantholysis. Which target antigen is implicated in the subcorneal pustular dermatosis type of this condition?
- A Type VII collagen
- B Desmoglein-3
- C Desmocollin-1 ✓
- D BP180
Correct answer: C. Desmocollin-1
Explanation
IgA pemphigus has two patterns: the subcorneal pustular dermatosis type, targeting desmocollin-1, and the intraepidermal neutrophilic type, targeting desmogleins or other desmosomal proteins. Intercellular IgA recruits neutrophils, producing pustules with little acantholysis, unlike pemphigus vulgaris where IgG against desmoglein-3 causes marked suprabasal acantholysis. Type VII collagen and BP180 are basement membrane antigens seen in EBA and bullous pemphigoid respectively.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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