Pustular drug eruption due to bacampicilin hydrochloride in a patient with psoriasis

We report a case of pustular drug eruption due to bacampicilin hydrochloride which developed in a patient with pustular psoriasis. The patient was a 45-year-old Japanese woman with psoriasis which started as pustular psoriasis twenty years previously. In 1994, she developed generalized erythema with pustules accompanied by high fever and liver injury. Clinical and histological findings of this pustular eruption were different from her previous episodes of pustular psoriasis. Erythemas and pustules disappeared and her abnormal transaminase returned to normal rapidly when she discontinued bacampicilin hydrochloride. Her positive reaction to a patch test and a lymphocyte stimulation test also suggested that our case had a pustular drug eruption rather than pustular psoriasis induced by a drug.