High rate of chronicity in HCV infection determined by antibody confirmatory assay and PCR in 4110 patients during long-term follow-up

Accuracy of HCV-RNA PCR tests for diagnosis or exclusion of vertically acquired HCV infection

The aim of the study was to estimate the sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and likelihood ratios for HCV-RNA PCR tests for the early diagnosis or exclusion of HCV infection in vertically exposed children. Data were included for children with confirmed HCV infection status from a European multi-center study. Confirmation was dependent on antibody status at or beyond 18 months, the 'gold standard' measure of infection status against which the use of qualitative HCV-RNA PCR tests was assessed. Of the 547 children included in this analysis, 193 were HCV-infected and 354 were not. Sensitivity of the HCV-RNA PCR test was low at birth (22%), but increased to 85% by 6 months. Specificity of RNA PCR was constant over age at 98%. The PPV of the PCR test rose from 33% at birth to 78% at 9 months of age, while NPV ranged from 96% to 99%. The high positive likelihood ratios from 1 month of age indicate strong evidence to diagnose infection but the negative likelihood ratios were consistent with weak evidence to exclude infection. The results suggest that the first qualitative HCV-RNA PCR test should be delayed until after the first month of life given the low sensitivity in the first few weeks. Although a negative test result after this time indicates probable absence of infection, this should be confirmed with a negative anti-HCV antibody test between 9 and 15 months of age as negative PCR results can be observed in infected children with fluctuations in viremia.

Hepatocellular carcinoma in a patient with liver cirrhosis associated with negative serum HCV tests but positive liver tissue HCV RNA

A 70-year-old woman was admitted to our hospital because of a liver tumor. Laboratory data revealed mild liver dysfunction. Neither serum anti-HCV antibody nor HCV-RNA was detected. Computed tomography revealed a tumor lesion measuring 2 cm in diameter within the liver. Histological examination of the tumor revealed moderately differentiated hepatocellular carcinoma while the non-tumorous liver tissue demonstrated liver cirrhosis. By the RT-PCR method, HCV-RNA was detected from the non-tumorous liver tissue. We herein report a very rare case of hepatocellular carcinoma in a patient with liver cirrhosis associated with negative serum HCV findings, but positive finding for liver tissue HCV RNA.

Genotyping of hepatitis C virus types 1, 2, 3, and 4 by a one-step LightCycler method using three different pairs of hybridization probes

Determination of hepatitis C virus (HCV) genotypes has become increasingly important during the last years for prediction of the clinical course and the outcome of antiviral therapy. Therefore, numerous different methods have been developed to enable HCV genotyping. However, many of them are very laborious and expensive, leading to limited usage in daily routine diagnostics. We have established a method which combines the speed of the new LightCycler technology with the use of amplification products generated for diagnostic quantitative HCV RNA determination. Differentiation of HCV genotypes is performed with these amplicons in a single step by using fluorophore-labeled hybridization probes. Although currently only two different acceptor fluorophores are available for the LightCycler, types 1, 2, 3, and 4, which are by far the prevailing HCV genotypes in Europe and the United States, can be distinguished. Genotypes of specimens from 190 chronically HCV-infected patients were determined by the LightCycler method and compared with the results of nucleotide sequencing. Concordant results were obtained for all samples. This new method offers a fast and convenient possibility to determine the quantitative HCV RNA load and the genotype in large-scale settings within about 4 h.

Relevance of reactivity in commercially available hepatitis C virus antibody assays

Sera from 2,148 patients were tested with a third-generation microparticle enzyme immunoassay (MEIA), a confirmatory assay, and a reverse transcription-PCR. Overall, 85.6% of reactivities were confirmed, 13.2% were shown to be unspecifically reactive, and 1.2% were indeterminate. The rate of confirmed MEIA reactivities clearly depended on the strength of the reactivity.