B-270 Validation of a New Molecular Assay for the Detection and Quantification of Hepatitis B Load in Plasma

Abstract Background Hepatitis B virus (HBV) is an enveloped DNA virus and is the most common worldwide cause of viral hepatitis in humans. It is primarily transmitted through blood or blood products. Although the diagnosis of hepatitis viral infections is usually performed with serological markers in blood, this technique has limitations and therefore the diagnosis of the disease by qPCR allows an improvement in the diagnosis of the infection, therapeutic decision making and evaluation of the response to treatment. Therefore, CerTest Biotec has developed a quantitative real-time PCR assay for the detection and quantification of hepatitis B virus in plasma samples. Methods Plasma-EDTA samples characterized as positive or negative and quantified in IU/ml were analyzed. The selected samples were collected from infants and adults of both sexes between September 2019 and August 2020. The origin of the population is diverse, with the majority being European. For comparative analysis, the cobas® HBV molecular assay (Roche Diagnostics) using the cobas® 8800 system was used. VIASURE analysis was performed using the following workflow: the MagDEA® Dx SV automated extraction method with magLEAD® 12gC and CFX96™ Opus Real-Time PCR Detection System (Bio-Rad). Results A total of 210 clinical EDTA plasma samples were tested, of which 110 were positive for hepatitis B virus and 100 were negative. The comparative analysis determined a sensitivity and specificity >99%. In addition, the positive predictive value (PPV) and negative predictive value were >99%. As for quantification, an R2 correlation value of 0.9095 was obtained. Conclusion This clinical evaluation demonstrated that the VIASURE HBV q Real Time PCR Detection Kit is a good tool for the clinical diagnosis of the virus as it has good sensitivity and specificity. No false positive or false negative results were observed. Moreover, the correlation of the quantification with the reference method gives a value of R2 > 0.9. Therefore, clinical diagnosis of hepatitis B virus by real-time PCR can encompass the limitations of the current diagnostic technique by serology.