Vancomycin-Induced Linear IgA Bullous Dermatosis Mimicking Stevens-Johnson Syndrome Associated With Anticancer Therapy.

Linear IgA bullous dermatosis (LABD), also known as linear IgA disease, is a subepidermal blistering disorder presenting with linear deposits of IgA along the basement membrane zone. Although LABD is commonly idiopathic, it can also rarely be triggered by certain drugs, including vancomycin. Herein, we document the rare case of a 41-year-old woman with a history of invasive ductal breast carcinoma, receiving an anticancer regimen of pembrolizumab, cyclophosphamide, and doxorubicin, who developed erythema, tense bullae, and extensive sloughing of skin after vancomycin therapy. Initially, the patient was suspected to have drug-induced Stevens-Johnson syndrome/toxic epidermal necrosis; however, biopsies of the right thigh revealed subepidermal bullous dermatosis with neutrophils and necrotic keratinocytes. Direct immunofluorescence revealed 3+/3+ anti-IgA and 1+/3+ anti-C3 deposits that were linear at the dermal-epidermal junction. The clinical and histopathologic findings confirmed the diagnosis of vancomycin-induced LABD. This report examines the complicated relationship between immunobullous disease, neoplasms, and oncologic treatment. Presented is a rare case of vancomycin-induced LABD in a patient receiving concurrent chemotherapy and immunotherapy. Clinician awareness of the increased susceptibility of vancomycin-induced LABD in this population subset can improve clinical outcomes and decrease morbidity/mortality.