Patients co‐infected with human immunodeficiency virus and hepatitis C virus demonstrate higher levels of hepatic HCV RNA

Abstract

Serum and liver hepatitis C virus (HCV) RNA levels in patients with hepatitis C have previously been quantified using different techniques. In this work, we used an automated, multicycle, polymerase chain reaction (PCR)‐based technique to quantify HCV RNA in 1–2 mm of frozen liver tissue, and in serum, from 70 patients with antibodies to HCV (anti‐HCV), with and without human immunodeficiency virus (HIV) co‐infection. Stored liver tissue and sera collected at the time of liver biopsy were used for measurement of HCV RNA. Forty‐eight HCV patients and 22 HIV/HCV co‐infected patients were studied. Co‐infected patients had significantly higher median serum and liver HCV RNA (6.7 log copies ml^–1 serum and 2.90 log copies μg^–1 liver nucleic acids) than patients with HCV alone (6.2 log copies ml^–1 serum and 2.19 log copies μg^–1 liver nucleic acids). There was only a weak correlation between serum and liver HCV RNA (r = 0.43). There was no correlation between liver and serum HCV RNA and host factors such as duration of disease, CD4 counts, alanine aminotransferase levels or histological score. There was no correlation with HCV genotype. Co‐infected patients were more likely to harbour HCV genotype 1 (85%) when compared to patients with HCV alone (58%). An identical genotype was found in liver and serum in 89% of those tested; in 11%, a mixed genotype was present in serum. Patients with HCV genotypes 1 and non‐1 had similar histological scores. Hence, an automated PCR‐based technique is useful for measuring both liver and serum HCV RNA. Serum HCV genotypes closely paralleled those found in liver tissue. HIV co‐infection was associated with higher serum, as well as intrahepatic, HCV RNA levels, by mechanisms not directly related to CD4 counts. The lack of correlation between liver HCV RNA and histology suggests that HCV is not directly cytopathic.