Occurrence of occult HCV infection among Hiv infected patients in Georgia.

Occult hepatitis C (OCI) infection has been known as detectable HCV-RNA in the liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable serum or plasma HCV-RNA. OCI has been detected among different patients groups worldwide, it has been found not only in chronic hepatitis patients of unknown origin, but also among several groups at risk for HCV infection (hemodialysis patients or family members of patients with occult HCV). This occult infection has been reported also in healthy populations without evidence of liver disease. Prevalence of occult Hepatitis C virus has not been investigated in Georgian population, where a rate of HCV infection is highest (6.7%) among Eastern European Countries. The aim of this study was to investigate the occurrence of occult HCV infection among HIV infected individuals in Georgia. As a pilot study, we have selected three groups of HIV infected patients for analyses: Group 1- HIV infected patients without evidence of liver disease (n=98), group 2- HIV infected patients with cryptogenic liver disease (n=34) and group 3- HIV/HBV co infected patients (n=29). HCV RNA was tested in PBMCs samples by real-time polymerase chain reaction. HCV genotyping was performed by Line-probe assay based on reverse-hybridization technology. Liver fibrosis was evaluated by transient elastography (FibroScan®). HCV-RNA was detected in PBMCs specimens among 2 (2%) subjects from group 1, 4 (12%) subjects from group 2, and 9 (31%) subjects from group 3. HCV genotypes were determined for 14 of 15 OCI subjects resulting following genotype distribution: 6 (46%) - 1b, 3 (23%) - 2a/2c and 5 (38%) - 3a. One samples failed to be genotyped due to extremely low HCV viral load. Our data revealed the occurrence of occult HCV infection in HIV infected patients. No single HCV genotype was predominant in the present study. Liver fibrosis was found more frequently and the fibrosis score was significantly higher in OCI patients versus negative ones, suggesting that undiagnosed OCI might impact on the liver damage. The study demonstrated that testing only for HCV antibody fails to identify the true prevalence of HCV co-infection among HIV infected patients. We propose that in the absence of liver biopsy specimens, analysis of PBMC sample for HCV-RNA would be informative for detection of occult HCV.