Case presentation: In this case presentation, an 84-year-old male with Fitzpatrick type IV skin tone experienced blistering due to bullous pemphigoid (BP), first on the distal upper left extremity and then on the distal lower extremities, chest, and back. These symptoms resulted in three visits to the emergency department within a month, as well as an episode of hospitalization. Despite treatment, the blistering did not resolve until future outpatient care with dermatology.
Discussion: Bullous pemphigoid is a rare autoimmune disease where autoantibodies target hemidesmosomal proteins causing basement membrane destruction and tense subepithelial bullae with pruritus. While uncommon, the incidence of BP is increasing. Bullous pemphigoid tends to affect older adults, appearing as a rash prior to bullae formation on the abdomen, extremities, groin, axillae, or mucosa. Bullous pemphigoid may also be drug-related with atypical symptoms. Diagnosis of BP should be based on immunopathology, and initial treatment of BP is through corticosteroid or doxycycline.