Performance evaluation of the Hologic Aptima HCV Quant Dx assay for detection of HCV RNA from dried blood spots

• Published in: Journal of clinical virology Vol. 112; pp. 40 - 44
• Main Authors: Catlett, Beth, Carrera, Alex, Starr, Mitchell, Applegate, Tanya L, Lowe, Peter, Grebely, Jason, Philip Cunningham, H.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2019
• Subjects: DBS; Diagnostic; Dried Blood Spot Testing - standards; Genotype; HCV; HCV RNA; Hepacivirus - genetics; Hepatitis C - diagnosis; Hepatitis C - virology; Humans; Molecular Diagnostic Techniques - standards; People who inject drugs; Reagent Kits, Diagnostic - standards; RNA, Viral - isolation & purification; Sensitivity and Specificity; Viral Load; HCV RNA; Diagnostic; People who inject drugs; HCV; DBS
• ISSN: 1386-6532; 1873-5967
• DOI: 10.1016/j.jcv.2019.01.010

•Aptima HCV detects HCV from dried blood spots with good sensitivity/specificity.•Dried blood spots are a suitable alternative to plasma for HCV RNA detection.•Dried blood spots could simplify and enhance HCV testing in people who inject drugs. The availability of effective direct-acting antiviral therapy for hepatitis C virus (HCV) has led to a need for simplified diagnostic pathways. Barriers to treatment uptake, specifically in people who inject drugs and in remote and resource limited settings, may be overcome by utilizing novel collection methods, such as dried blood spots (DBS). However, there are currently no registered assays for HCV RNA testing from DBS samples. To evaluate the sensitivity and specificity of the Aptima HCV Dx Quant assay for HCV RNA detection in DBS samples 107 paired venepuncture and DBS samples from HCV antibody positive individuals were analyzed for HCV RNA on the Aptima HCV Dx Quant and Roche CAP/CTM (gold standard) HCV assays. 78% (n=83) had detectable HCV RNA in plasma. Sensitivity of the Aptima assay for HCV RNA detection in DBS was 96.4% (95% CI 89.8–99.3%) and specificity was 95.8% (95% CI 78.8–99.9%). Sensitivity for HCV RNA detection in DBS using a quantitative threshold of ≥15 IU/mL in plasma was 95.1% (95% CI 88%–98.7%) and specificity was 96.0% (95% CI 79.7%–99.9%). The sensitivity of HCV RNA detection in DBS using a quantitative threshold of ≥1000 IU/mL (based on a clinically relevant threshold) was 100% (95% CI 95.3–100%) and specificity was 100% (95% CI 88.4–100%). Our data indicates that the Aptima HCV Dx Quant can detect active HCV infection from a DBS sample with good sensitivity and specificity, particularly when using a threshold of ≥1000 IU/mL.