A 40-year-old woman (gravida 2, para 2) presented to the emergency department nine days postpartum with a four-day history of progressive pruritic rash. Exam The rash had initially appeared peripherally on the limbs and later progressed to involve the trunk, abdomen, and back. The palms of the hands and soles of the feet were spared, and there was no mucosal involvement. She had no medical history and was not taking any medication. A previous HIV test and herpes simplex virus titers had been negative.

She had presented following a spontaneous delivery after an uneventful pregnancy. On examination, she had numerous tense fluid filled blisters affecting her hands, feet (image 1), and flexor and extensor aspects of all limbs. Diffuse erythematous pruritic plaques were also present over her torso. Some blisters had burst due to positional pressure, however, Nikolsky’s sign was negative.…