Sensitivity and specificity of dried blood spot samples for hepatitis C virus RNA testing.

BACKGROUND: Dried blood spot (DBS) samples can improve access to hepatitis C virus (HCV) testing among hard-to-reach and underserved populations. We conducted a multicentre diagnostic accuracy study to evaluate the clinical performance of the Abbott RealTime HCV assay on the m2000 platform for detecting HCV RNA, using a standardized DBS collection and elution protocol. METHODS: The study was conducted at four sites in Cameroon, Rwanda, Georgia and Greece. DBS prepared from capillary and venous blood samples were collected from three target populations; individuals at risk of HCV infection, persons living with HCV, and individuals previously treated for HCV. Plasma samples tested on the Abbott m2000 platform served as the reference standard. RESULTS: A total of 936 participants were enrolled, of whom 76.6% were HCV antibody positive. Both capillary and venous DBS demonstrated high diagnostic accuracy. Sensitivity and specificity were 95.2% (95% CI: 92.9-96.8) and 95.6% (95%CI: 93.3-97.1) for capillary DBS, and 95.4% (95% CI: 93.1-97.0) and 96.0% (95% CI: 93.8-97.4) for venous DBS. The Abbot RealTime HCV assay on the Abbott m2000 platform showed strong clinical performance for detecting HCV RNA from DBS. CONCLUSION: These findings support the use of DBS as a feasible and less resource-intensive alternative to plasma-based testing, potentially expanding HCV screening and diagnosis in decentralized settings. Reliable DBS testing relies on proper sample collection, appropriate handling, and adequate staff training. GOV IDENTIFIER: NCT03896087 (registered on 14 March 2019) available here: Study Details | Evaluation of Dried Blood Spot for HCV RNA Testing | https://clinicaltrials.gov/ .