PAINFUL BLISTERS ON ARMS ...

A 7-year-old girl presented to the emergency department with a 2-week history of fever and with several days of painful blisters on her arms, legs, and face. Two weeks earlier, she had completed a course of penicillin for tonsillitis. Despite treatment with antibiotic agents and acyclovir, the lesions progressed. Tests for infectious causes, including blood cultures, serologic testing for Epstein-Barr virus and Mycoplasma pneumoniae, wound testing for herpes simplex virus and varicella zoster virus, and bacterial culture, were negative. On hospital day 5, a new skin ulcer developed on the right hand at an intravenous cannula site. suggest the suitable line of treatment