Performance of a novel DiaRD-HCV RNA RTqPCR kit for quantification of HCV RNA in clinical samples

Quantitative detection of hepatitis C virus (HCV) RNA is essential for diagnosis of chronic infection and monitoring the HCV levels in patients under treatment. In this study, we aimed to evaluate the performance characteristics and comparability of a novel DiaRD-HCV RT qPCR kit (Diagen Lts, Ankara, Turkey) with Artus HCV QS-RGQ kit and the NeuMoDx HCV Quant Test in clinical samples.

A total of 240 plasma samples, 86 HCV RNA positive and 154 negative, were used for comparison. Intra-assay and inter-assay reproducibility tests of the novel kit were carried out on clinical samples having HCV RNA loads of 1.42 × 10³ IU/µl, 1.40 × 10⁴ IU/ml, and 5.10 × 10⁵ IU/ml. HCV genotypes 1b, 2a, 2b, 3a, 4, 5, and 6 were tested by the novel system.

DiaRD HCV RTqPCR kit demonstrated a sensitivity of 98.8%, a specificity of 100%, and an accuracy of 99.6%. Linear regression analysis demonstrated strong correlation (R² = 0.915) on paired quantitative results. There was a good agreement between the novel kit and two comparator kits, with an overall mean difference of -0.12 log10 IU/ml obtained by Bland-Altman analysis. According to different viral loads, the intra-assay, inter-assay, and inter-load coefficients of variations (CVs) of the novel kit ranged from 5.31% to 11.73%, from 9.31% to 17.16%, and from 4.25% to 15.38% repeats. P-values were between 0.3 and 0.9, confirming no significant variations in the quantitative results of the reproducibility experiments. All genotypes tested were detected and quantitated with the mean differences between 0.01 and 0.62 log10 IU/ml. The primers and probe used in the novel kit did not result in any false-positive results with other pathogens.

These results highlight the potential utility of the DiaRD HCV RTqPCR kit for quantitation and monitoring of HCV RNA in patients.