Human immunodeficiency virus infection and porphyria cutanea tarda: coexistence of risk factors or causative association?

Several recent reports have described an association between human immunodeficiency virus (HIV) infection and porphyria cutanea tarda (PCT). We describe two HIV-infected patients who developed PCT and review 29 other reported cases of coexistent PCT and infection due to HIV. Recognized porphyrinogenic factors were identified in our patients and in 27 of the 29 cases described in the literature. Even in the two cases that lacked obvious precipitant factors for PCT, the possibility of hepatitis C was not excluded. This fact suggests that the co-occurrence of PCT and infection due to HIV may reflect the coexistence of risk factors for the two diseases rather than a causal association. Despite concern that exposure to sulfonamides might exacerbate porphyria, one of our patients and three patients described in the literature were safely treated with sulfonamides.