Detection of CMV DNA: is EDTA whole blood superior to EDTA plasma?

The early diagnosis of human cytomegalovirus (CMV) infection in immunosuppressed patients has been improved by molecular detection of CMV DNA. In this study, corresponding EDTA whole blood and EDTA plasma specimens were obtained from 42 bone marrow transplant recipients. For detection of CMV DNA, two commercially available assays, the CMV HHV6,7,8 R-gene (ARGENE), and the artus CMV LC PCR Kit (QIAGEN), were employed. The linearity of both assays was determined by using a clinical EDTA whole blood sample with high CMV DNA load. With the CMV HHV6,7,8 R-gene test, CMV DNA was detected in 40 EDTA whole blood and in 19 EDTA plasma samples, while the artus CMV LC PCR Kit test detected CMV DNA in 27 EDTA whole blood and in 30 EDTA plasma samples. In conclusion, EDTA whole blood samples were found to be the superior material when using the CMV HHV6,7,8 R-gene test. However, this benefit may not exist when employing alternative assays.