A 64-year-old female with a history of uncontrolled diabetes, high blood pressure and chronic diarrhea presents with recurrent, non-painful, mildly pruritic, clear fluid-filled blisters lesions for one year, now occurring more frequently on multiple sites including the upper extremities, hands, abdomen, and feet. She denies any fever, dizziness, dyspnea, difficulty swallowing or breath, nor joint pain. She denies exposure to new medications since the complaint began, new foods, or new skin products, and she denies recent upper respiratory tract infection and known allergies. She has not previously received treatment for this complaint and has only utilized wound care for the “open areas” when the blister pop.

On examination, there are tense and fewer decompressed bullae and both crusted and moist ulcerations on the upper extremities, dorsal hands, abdomen, and dorsal feet. There is no involvement of the scalp, conjunctiva, oral or genital mucosa. You suspect BP and decide to perform punch biopsies for histopathology (H&E) and direct immunofluorescence (DIF) to confirm the diagnosis.