A man in his 70s with a history of chronic lymphocytic leukemia (CLL) and prescribed cyclosporine, 100 mg twice daily, for pure red cell aplasia was admitted for spreading painful blisters on the hands and feet. He had initially developed rhinorrhea, cough, and low-grade fever 2 weeks prior. The patient was treated with azithromycin and subsequently developed few small, pruritic blisters on the hands and feet. He went to an urgent care facility and was diagnosed as having bronchitis and prescribed doxycycline and diphenhydramine. Over the next several days, he developed worsening fever, chills, and blisters and bullae on the arms, legs, and face. He was admitted to the hospital, and the dermatology service was consulted. Physical examination revealed numerous pink to violaceous macules, papules, and patches on the palms, dorsal hands, forearms, elbows, feet, and distal lower extremities (Figure, A and B). Fewer, scattered macules were on the face, neck, trunk, upper legs, upper arms, and scrotum. Dusky bullae were seen on the bilateral dorsal aspect of the hands, fingers, toes, and heels. In the oral cavity, there was 1 violaceous macule on the right buccal mucosa and a few linear, horizontal, white lines on the left buccal mucosa. Laboratory findings revealed a white blood cell count of 25 600/μL (reference range, 3700-10 500/μL) and a platelet count of 12 400/μL (reference range, 15 000-40 000/μL). Results from a Tzanck smear from the initial lesion on the right dorsal aspects of the third finger were negative for multinucleated giant cells. A punch biopsy was performed on the anterior side of the thigh (Figure, C and D).
Sidey KA, Willis MSJ, Wanat KA. Diffuse Vesicular Eruption. JAMA Dermatol. 2017;153(2):219-220. doi:10.1001/jamadermatol.2016.3751