Prevalence of hepatitis C virus infection in porphyria cutanea tarda: systematic review and meta-analysis

Background/Aims: To conduct a systematic review and meta-analysis on the prevalence of hepatitis C virus (HCV) infection in porphyria cutanea tarda (PCT). Methods: Studies evaluating prevalence of HCV infection in patients with PCT were considered. Bibliographical searches were conducted in several electronic databases. Studies comparing HCV prevalence in PCT (cases) and in a reference group (controls) were included in the meta-analysis, combining the Odds Ratios (OR) of the individual studies. Results: Fifty studies including 2,167 patients were identified. Mean HCV prevalence by serology was 47%, and 50% with polymerase chain reaction (PCR). HCV prevalence markedly varied depending on the country and the type of PCT (57% in the sporadic and 26% in the familial form). Eight case-contol studies were identified. Seven studies compared HCV prevalence in PCT vs. healthy controls: 40% vs. 0.24%, respectively (OR=275; 95% confidence interval=104-725). Heterogeneity disappeared when only studies evaluating HCV infection by PCR were included. Conclusions: HCV prevalence in patients with PCT is approximately 50%, much higher than that reported in general population, suggesting a possible etiopathogenic role of HCV in PCT. The striking geographical variation in this association suggests that genetic and/or environmental factors may also be involved in the pathogenesis of this disorder.