High prevalence of hepatitis C virus type 1b in Italian patients with Porphyria cutanea tarda

BACKGROUND: A strong association between sporadic porphyria cutanea tarda and chronic hepatitis C virus infection was recently described in Italy, France and Spain. AIMS: To explore whether hepatitis C virus genotype plays a role in porphyria cutanea tarda complicating chronic hepatitis C. PATIENTS: Forty-seven hepatitis C virus-positive porphyria cutanea tarda patients and a control group of 45 patients of similar age with hepatitis C virus-associated chronic liver disease. METHODS: Comparison of frequency of hepatitis C virus genotypes in the two groups and in relation to the age of patients, hepatic histopathology and with the presence of other factors potentially able to trigger porphyria cutanea tarda. RESULTS: A single genotype, hepatitis C virus 1b, was found to be present in nearly 90% of porphyria cutanea tarda-associated chronic liver disease, significantly exceeding the frequency of the same genotype in the control group (p = 0.0001). The presence of hepatitis C virus 1b was not related to the age of patients or disease severity as evaluated by hepatic histopathology. CONCLUSIONS: Hepatitis C virus-associated chronic hepatitis found in the majority of Italian patients with porphyria cutanea tarda is usually sustained by hepatitis C virus genotype 1b. This viral strain might have a direct pathogenic role in inducing porphyria cutanea tarda or could increase the susceptibility of patients of other triggering factors such as iron overload or alcohol abuse.