Investigation of hepatitis C virus RNA in samples other than blood

Hepatitis C virus (HCV) is the one of major causes of chronic hepatitis, cirrhosis and hepatocellular carcinoma. Hepatitis C infection becomes chronic in about 70-80% of cases and mostly do not exhibit any symptoms for years.It is not clear how hepatitis C cause chronic infection or resists to interferon+ribavirin treatment. There are conflicting data related to role of extrahepatic HCV replication on transmission, escape from the immune response and failure of therapy. This study aimed to make a contribution on this field by investigation of presence of HCV RNA in saliva, urine and stool from patients with chronic Hepatitis C. Any positive result at saliva, urine and stool samples compared with the result of same patients? plasma for viral load and HCV genotype. Hypothesis of this study was that HCV is present on different compartments of the body of patients with chronic hepatitis C infection and there is no difference among compartments regarding the viral loads.Plasma, saliva, urine and stool samples of 15 chronic hepatitis C patients were analyzed for the presence of HCV RNA by a quantitative real time reverse transcriptase polymerase chain reaction (RT-PCR) assay. Nucleic acid isolation was done by QIAamp® Viral RNA Mini Kit (Qiagen, Germany) with some modifications for non-plasma samples in order to have the best sensitivity in the assay. The commercial RT-PCR (Artus HCV RG RT-PCR Kit, Qiagen, Germany) assay was performed with a Rotor-Gene 3000 (Corbett Research, Australi). When plasma and any of the non-plasma samples of the same patient were positive, HCV genotype was determined by restriction fragment length polymorphism analysis.Ten of 15 patients? plasma samples were HCV RNA positive. Among these patients? samples, one of saliva, urine and stool samples, each belonging to a different patient were also HCV RNA positive. Viral loads of the non-plasma samples were either equal or lower than the same patients? plasma viral load. HCV genotype of plasma samples was determined as genotype 1. Genotyping of non-plasma samples could not be completed due to the low viral load of the samples. In conclusion, it was shown that HCV RNA is present and detectable in non-plasma samples.Key words: Hepatitis C Virus, Polimerase Chain Reaction, Genotyping