Investigating the presence of different hepatitis C virus genotypes in serum, peripheral blood mononuclear cells, and liver biopsy specimens of patients with hepatitis C virus infection

Hepatitis C virus (HCV) is essentially considered as hepatotropic, but virus sequences have also been found in other important extrahepatic sites, including peripheral blood mononuclear cells (PBMCs). This study was done to investigate the presence of mixed infection and the differences between hepatitis C virus genotypes in plasma, peripheral blood mononuclear cells, and liver biopsy specimens in patients with hepatitis C virus infection. One hundred and fifty two patients with established chronic hepatitis C infection attending Firouzgar Hospital, affiliated to Tehran University of Medical Sciences, from September 2008 to April 2010 were enrolled in the present study. After collecting plasma, peripheral blood mononuclear cell, and liver biopsy specimens, RNA was extracted from the samples and hepatitis C virus genotyping was performed using INNO-LiPATM HCV II kit. The hepatitis C virus genotyping was confirmed by sequencing the RT-nested PCR product of 5'-UTR fragments. The mean age of the participants was 31.2±16.9 years. Multiple hepatitis C virus genotypes were detected in 4 (2.6%) out of 152 plasma samples, 10 (6.6%) out of 152 peripheral blood mononuclear cell samples, and 9 (18.8%) out of 48 liver biopsy specimens. Hepatitis C virus genotypes were different in the plasma, PBMC, and liver biopsy specimens of 21 (13.8%) patients. The present study shows that a significant proportion of patients with chronic hepatitis C infection are infected by multiple hepatitis C virus genotypes which may not be detectable in their plasma specimens.