Itchy, tense blisters

Case #1

A 94-year-old woman presents with a 10-day history of itchy, tense blisters that break open and leave a hemorrhagic crust. She has no other symptoms and was taking lisinopril, hydrochlorothiazide, and simvastatin. Physical exam revealed scattered, tense bullae over normal and erythematous skin in symmetrical distribution on the lower back as patchy coalescing erosions and on the inguinal region; ...