Human herpesvirus-6 as an inducer of porphyria cutanea tarda: implications from a case.

Here we describe a case that might deliver a link between sporadic porphyria cutanea tarda (PCT) and human-herpesvirus-6 (HHV6) hepatitis. Sporadic PCT is a rare disease of the heme synthesis pathway. The pathogenesis has not been fully determined but iron overload and viral infections - e.g., hepatitis C virus - are thought to play an important role. We present the case of a patient suffering from myelo-monocytic leukemia. He developed symptomatic sporadic PCT concomitant with HHV6-associated subclinical hepatitis after allogeneic stem cell transplantation (SCT). Although HHV6 often reactivates after SCT and HHV6-induced hepatitis can occur in immunocompromised patients, it has not been described that HHV6 might trigger PCT. A contribution of HHV6 to the pathogenesis of sporadic PCT could have dramatic implications on our current therapeutic approach.