Drug eruption due to peplomycin: an unusual form of Stevens-Johnson syndrome with pustules.

A rare case of Stevens-Johnson syndrome (SJS) due to peplomycin in a 48-year-old man is described. The patient had squamous cell carcinoma on the scalp and underwent preoperative neoadjuvant chemotherapy with peplomycin. On the fifth day of the chemotherapy, he developed a fever and multiple dusky violaceous erythematous areas and pustules on his trunk, thighs, and palms. Erosive erythema and erosions also developed on his soles, scrotum, and oral mucosa. A biopsy specimen taken from the eruption on the thigh revealed marked liquefaction degeneration of the basal layer of the epidermis. Laboratory examinations demonstrated aggravation of liver function. Additionally, the patient developed conjunctivitis and corneal erosions. Although he had some subcorneal pustules, we diagnosed the case as an unusual form of SJS because of severe mucous membrane involvement. Oral prednisolone was administered, and the symptoms subsided. Then the patient underwent wide local excision. One month after surgery, we performed patch tests and a lymphocyte stimulation test with negative results. Then we re-administered peplomycin starting with 1/20 of a daily dose and gradually increasing the dose each day. After administration of the regular daily dose, the patient had a relapse of fever, eruptions, stomatitis, corneal erosions, and liver dysfunction. Therefore, a definite diagnosis of drug eruption due to peplomycin was made.