Idiopathic Linear IgA Bullous Dermatosis Complicated by MSSA Bacteremia: A Case Report

Background Linear IgA Bullous Dermatosis is a rare autoimmune dermatological disorder caused by the deposition of IgA autoantibodies along the basement membrane of the dermis. This condition typically manifests as pruritic, erythematous vesicles that may coalesce. It can be idiopathic or associated with medication use, malignancy, or other autoimmune diseases. The incidence is estimated at 0.2–2.3 cases per million people per year. Prompt recognition and dermatology consultation are crucial for diagnosis, management, and prevention of complications such as superimposed infections. Case presentation We report a case of idiopathic linear IgA bullous dermatosis in a 34-year-old female who presented to the emergency department with a worsening pruritic rash involving her arms, legs, and torso persisting for three weeks without improvement. She was initially hemodynamically stable; however, laboratory results were notable for leukocytosis. Dermatology was consulted, and diagnostic workup, including direct immunofluorescence and skin biopsy confirmed a diagnosis of linear IgA bullous dermatosis. The patient was admitted and started on systemic corticosteroids. While she showed mild improvement, her hospital course was complicated by methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia. She was discharged with a midline catheter for outpatient Cefazolin administration and was prescribed Prednisone and Dapsone. Conclusions Linear IgA bullous dermatosis is an important yet rare autoimmune condition to consider in patients presenting to the emergency department with undifferentiated rashes. Early recognition and prompt dermatological consultation can expedite diagnosis and management. Given that fatal outcomes have been reported in drug-induced cases, timely initiation of treatment, particularly corticosteroids, is critical to prevent disease progression.