(423) Linear IgA Bullous Dermatosis: Confounding Mimic of Stevens-Johnson Syndrome

Track
Case Reports
Abstract

Background: Linear IgA bullous dermatosis (LABD) is a subepidermal blistering disorder with linear deposits of IgA along the basement membrane zone (BMZ). While often idiopathic, LABD can be medication-induced, with vancomycin representing the most common culprit. LABD can rarely occur with a blistering and sloughing clinical presentation, representing an unusual mimic of Stevens-Johnson Syndrome (SJS)/toxic epidermal necrolysis (TEN).

Objective: A rare case of vancomycin-induced LABD characterized by extensive skin sloughing was initially suspected as SJS/TEN in a patient with multiple medical co-morbidities. Diagnostic challenges and consequent treatment implications are discussed. 

Case Presentation: A 41-year-old female with history of breast carcinoma, intravenous illicit drug use, and cirrhosis developed erythema, few tense bullae, and extensive skin sloughing after vancomycin treatment for suspected tricuspid valve endocarditis. SJS/TEN was suspected based on clinical presentation, and consideration was given to transferring the patient to a burn unit. Skin biopsies were performed to exclude mimickers of SJS/TEN. Two separate biopsies revealed a subepidermal bullous and vesicular dermatosis with linear distribution of neutrophils and necrotic keratinocytes. Direct immunofluorescence from perilesional skin showed linear 3+/3+ anti-IgA and 1+/3+ anti-C3 deposits at the dermal-epidermal junction, confirming the diagnosis of LABD. Due to other comorbidites, the patient's condition rapidly deteriorated, necessitating a transition to comfort care and precluding treatment of her LABD.

Conclusion: It is important to consider drug-induced LABD in the differential diagnosis of SJS/TEN, as treatment, prognosis, and drug culprits differ for these two entities. In this particular case, a potentially unnecessary transfer to a burn unit was avoided.

Published in: ASDP 61st Annual Meeting

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