Evaluation of true point of care molecular assay using fingerstick capillary whole blood for diagnosis of hepatitis C infection.

Abstract

At present, the available point of care (POC) molecular assays for hepatitis C are not considered as true POC due to sample collection and processing requiring minimal laboratory infrastructure. A new POC Xpert HCV VL Fingerstick (Xpert FS) precludes such requirements where specimen collected by simple fingerstick can be loaded directly into the test cartridge with results available within 60 min. The present study compared the performance of this assay for HCV RNA quantitation using both capillary whole blood (CWB) and venous whole blood (VWB) with plasma HCV RNA performed on Abbott Real Time HCV PCR. CWB via fingerstick and VWB via venipuncture collected from serologically confirmed HCV-infected participants were loaded into Xpert HCV VL WB for viral load estimation. Simultaneously Abbott Real Time HCV PCR assay was also performed using plasma (reference method). Among the enrolled participants (n=157), the mean age was 46.22±14.79 years and 63 % were male. HCV RNA was detected in 100 cases (63.7 %), median 5.69 (IQR: 5.00-6.32)log10IU ml-1 on the reference method. Xpert FS showed 100 % sensitivity and specificity using both CWB and VWB. The median viral loads detected in CWB and VWB were 5.52 (IQR: 4.59-6.15) and 5.48 (IQR: 4.61-6.07)log10IU ml-1, respectively. Xpert FS offers potential as true POC enabling accurate diagnosis in a single patient visit to the health-care facility, hence may reduce the number of dropouts with a confirmed diagnosis. However, further real-time studies with larger sample size are warranted.