Determinazione quantitativa di HCV-RNA: valutazione comparativa dei saggi Abbott Real-Time e Versant bDNA v.3

Hepatitis C virus (HCV) RNA measurement before, during and after antiviral therapy has become an essential tool in the management of interferon-based treatment of HCV-related infections. Conventional Polymerase Chain Reaction (PCR) has been largely used to obtain quantitative data, but laborious, time-consuming post-PCR handling steps are required to gain valuable results. Real time (RT) PCR now provides advantages over end-point (EP) PCR due to its improved rapidity, sensitivity, reproducibility and the reduced risk of carry-over contamination, and has now proven itself to be valuable for the more precise monitoring of viral load kinetics and assessing antiviral response.The Abbott Real-Time HCV-RNA is a recently introduced assay for the automated processing of clinical samples and HCV-RNA quantitation: its basic technology relies on use of fluorescent linear probes (dynamic range using 0.5 ml as input target= 12-108 IU/mL) and a hybridization/detection step at low temperature (35°C), which allows target mismatches to be tolerated. To determine the clinical application of the Abbott Real-Time assay and defining its correlation with the Bayer Versant bDNA v.3 assay, 68 consecutive samples from unselected HCV-infected patients were retrospectively analysed with RT and the results obtained using the two tests compared.A good correlation was found between RT-PCR and bDNA: 97% of samples tested had a result within a 0.5 log HCV IU/mL difference (bias=0.15 log), whereas 6 samples negative with bDNA gave positive results with Abbott RT (range, 1.89-3.07 log IU/mL) and “in-house” qualitative RT-PCR assays.