Hepatitis C virus infection detected by viral RNA analysis in porphyria cutanea tarda.

The high prevalence (62%) of anti-HCV in patients with porphyria cutanea tarda (PCT) found in a recent study prompted us to speculate that hepatitis C virus (HCV) infection could contribute to liver damage in this disease. The relationship between a positive serologic test and infectivity remains elusive, as anti-HCV false-positive reactivity has been described in some patients with chronic liver disease. Hence, it needs to be established if HCV infection plays a role in the pathogenesis of liver injury, or anti-HCV positivity may be an epiphenomenon in PCT patients. The aim of this study was to evaluate the existence of true HCV infection by verifying the presence of serum viral RNA in patients with PCT. HCV RNA was studied in sera from 36 patients with clinical and biochemical features of PCT using a polymerase chain reaction technique. Additionally, 26 patients with chronic alcoholic liver disease and 29 patients with different dermatological lesions but with no liver disease were studied as control groups. HCV RNA was positive in 29 of 36 patients (80.5%) with anti-HCV positive PCT. For alcoholic liver disease and dermatological disease controls the values for HCV RNA were 11.5% and 3.4%, respectively. HCV infection was found to be significantly higher in patients with PCT than in controls (P < 0.001), demonstrating that most subjects with clinically expressed PCT have true HCV infection. These data support the hypothesis that liver damage in some patients with PCT may be attributed to prolonged HCV infection, suggesting that treatment for chronic hepatitis C could be indicated.