Porphyria cutanea tarda and systemic lupus erythematosus.

The co-existence of systemic lupus erythematosus and porphyria although rare has been known for a long time. This association forces the physician to make a careful differential diagnosis of the bullous lesions that might appear in such patients and to be careful when prescribing certain drugs such as chloroquine. This drug, when used in the regular doses for treating lupus, may cause hepatotoxicity in patients.suffering from porphyria. It is described here the case of a patient with lupus who developed bullous lesions compatible with porphyria cutanea tarda.