Track
Case Reports
Abstract

Bullous pemphigoid (BP), an autoimmune blistering disease with antibodies directed at Collagen type XVII NC16A domain with epitope spreading to involve other auto-antigens, classically presents with randomly distributed large, tense bullae. In contrast, vesicular pemphigoid (VP), a morphologic subtype of bullous pemphigoid, presents with symmetrically distributed small tense vesicles. It has been reported primarily in the elderly but has also been seen in children and has a clinically milder course than BP.

Our patient, an 88-year-old female, with a past medical history of chronic kidney disease, coronary artery disease, and dyslipidemia, presented with an acute skin eruption. On exam, there were numerous 2-3 mm severely pruritic pink papules and vesicles scattered on torso, arms, and legs. Hematoxylin and Eosin stain showed eosinophilic spongiosis with an intraepidermal vesicle containing eosinophils, and focal acantholysis. In the superficial dermis, there is a dense lymphocytic infiltrate with many eosinophils. A mite was not identified. Direct immunofluorescence showed 2+ linear IgG along the basement membrane zone in an n-serrated pattern. IgA and C3 did not show immunoreactivity. She responded well to treatment with topical triamcinolone 0.1% cream and doxycycline, and therapy has been completed without disease relapse.

This case highlights a rare presentation of BP that may escape diagnosis, as it is not typical for immunobullous disease. Dermatitis herpetiformis has morphologically similar lesions, but concentrated on elbows and knees, with papillary dermal IgA deposition. Scabies may have a DIF similar to BP and must be excluded by histology or clinical course.

Published in: ASDP 61st Annual Meeting

Publisher: The American Society of Dermatopathology
Date of Conference: November 4-10, 2024