This 25-year-old man with psoriatic arthritis and widespread psoriasis, who was treated with combination oral methotrexate 15 mg/week, and subcutaenous tumor necrosis factor blocker (Enbrel) 25 mg twice weekly, developed a minimally pruritic eruption on the back of scalp followed 1-2 days later by a widespread vesicular eruption on the trunk, extremities, and mouth. A Tzanck preparation showed multinucleated giant cells, and aulture for Herpes simplex virus were negative. Treatment was temporarily discontinued pending culture results and the clinical course, and oral valacyclovir was started at 1 gram orally 3 times daily. He never felt ill or developed fever, and within 3 days he stopped developeing new lesions. All lesions had fully crusted 10 days later. He had a history of varicella at under 10 years of age and denied recent exposure to varicella. The generalized eruption was preceded by a crusted eruption on the back of the scalp for 4-5 days consistent with shingles.
2-4 mm scattered red papules and vesicles on a red base