Rapid quantitation of cytomegalovirus DNA in whole blood by a new molecular assay based on automated sample preparation and real-time PCR

Abstract

Quantitation of cytomegalovirus (CMV) DNA in whole blood samples has gained significance in the routine diagnostic laboratory. In this study, the analytical performance of the artus™ CMV RG PCR kit in conjunction with automated sample preparation on the new QIAsymphony™ SP instrument was evaluated. Clinically referred samples were tested and results compared to those obtained with the routinely used molecular test system. Accuracy testing showed results to be within ±0.2 log(10) unit of the expected panel results. The assay was linear (R = 0.9972) from a lower quantification limit of 148 copies/ml to 1.3 × 10(7) copies/ml. The between-day imprecision CV was 8-63%, and the within-run imprecision CV was 16-61%. When 100 clinically referred samples were tested, results obtained with the new test system showed an acceptable concordance with those obtained with the routinely used easyMAG™ sample preparation and CMV HHV6,7,8 R-gene™ test system. Discrepant results were found with low-titer samples containing CMV DNA concentrations under the lower limit of quantification or within half a log unit above. The time to results was comparable for both test systems. The QIAsymphony™ sample preparation and artus™ CMV RG PCR test system allows for a rapid, sensitive, precise, and accurate high-throughput quantitation of CMV DNA in whole blood in the routine diagnostic laboratory.