Quantitative branched DNA assay and genotyping for hepatitis C virus RNA in Chinese patients with acute and chronic hepatitis C.

To determine the value of a quantitative branched DNA (bDNA) assay for detection of hepatitis C virus (HCV) RNA, 309 serum specimens were collected from 100 patients with acute or chronic hepatitis C for detection of HCV RNA by bDNA assay and reverse transcription-polymerase chain reaction (RT-PCR) assay. There were 256 samples positive by RT-PCR; 199 (78%) were also positive by bDNA assay. All but 1 of the remaining 53 samples negative by RT-PCR were also negative by bDNA assay. Combination of the two methods clearly demonstrated changes in HCV RNA titers during and after interferon (IFN) treatment. The most common genotype of HCV infection was Okamoto type II (Simmonds type 1b, 60.0%), followed by type III (type 2a, 16.5%) and type IV (type 2b, 8.2%); mixed or underdetermined types were noted in 15.3%. Patients with chronic type II HCV infection tended to have higher HCV RNA titers. These findings suggest that the bDNA assay is a reliable test for HCV RNA.