Hepatic porphyrin concentration and uroporphyrinogen decarboxylase activity in hepatitis C virus infection

Previous studies have shown a high prevalence of hepatitis C virus (HCV) in fection in patients with porphyria cutanea tarda (PCT). The aim of this stu dy was to assess hepatic porphyrin concentrations (HPC) and hepatic uroporp hyrinogen decarboxylase (UROD) activity in HCV-infected patients free of PC T. Thirty-two HCV-infected patients (20 M, 12 F, mean age 51 years) and sev en control patients (4 M, 3 F, mean age 59 years) free of liver disease, we re studied. Knodell's score was determined on liver biopsy by two independe nt anatomopathologists. Measurement of HPC and hepatic UROD activity levels were carried out on liver biopsy. Relative to controls, HCV-infected patie nts had high HPC levels (mean +/- SD: 47 +/- 20 vs. 17 +/- 6 pmol/mg protei n, P < 0.001) and low hepatic UROD activity levels (514 +/- 95 vs. 619 +/- 125 pmol Copro/h/mg protein, P < 0.05). HPC was not correlated with hepatic UROD activity and the increase was due to coproporphyrin accumulation. No correlation was observed between HPC or hepatic UROD activity values and HC V-RNA concentrations, Knodell's score, hepatic fibrosis, periportal necrosi s, periportal inflammation or hepatic iron content in HCV-infected patients . Hepatocellular necrosis was significantly correlated with HPC value (P < 0.005). Hence, in HCV-infected patients, HPC is significantly increased and hepatic UROD activity is very slightly decreased as compared to controls. HPC values and UROD activity are not correlated with HCV-RNA concentrations , hepatic iron content and hepatic fibrosis. The small increase in HPC valu es in hepatitis C infection is linked with hepatic injury and not with a di rect effect on hepatic UROD enzyme.