Comparative quantitation of cytomegalovirus (CMV) DNA in solid organ transplant recipients with CMV infection by using two high-throughput automated systems

Cytomegalovirus (CMV) DNA quantitation in clinical specimens is progressive ly becoming a cornerstone in the diagnosis and management of CMV infection in the immunocompromised host. We evaluated two automated and reproducible PCR tests, the LightCycler (Roche Molecular Biochemicals, Indianapolis, Ind .) and the COBAS AMPLICOR CMV Monitor (Roche Diagnostics, Pleasanton, Calif .), for the detection of CMV DNA in blood samples from transplant recipient s with CMV infection as determined by shell vial culture. Following a log t ransformation analysis, the mean CMV DNA in plasma (PL), whole blood (WB), peripheral blood leukocytes (PBL), and peripheral blood mononuclear cells ( PBMC) using the LightCycler was 6.79 copies per ml, 7.23 copies per ml, 6.3 8 copies per 2 x 10(6) Cells, and 6.27 copies per 2 x 10(6) cells, respecti vely. This compares to 7.86 copies per ml, 8.37 copies per ml, 7.59 copies per 2 x 10(6) cells, and 7.44 copies per 2 x 10(6) cells, respectively, usi ng COBAS AMPLICOR CMV Monitor. While higher CMV DNA levels were observed fo r the various blood compartments analyzed using COBAS AMPLICOR CMV Monitor, a high degree of correlation was evident between the two automated systems (jackknife correlation r = PL 0.77 [95% confidence interval (CI); 0.64, 0. 901, WB 0.77 [95% CI; 0.62, 0.921, PBL 0.77 [95% CI; 0.67, 0.88], and PBMC 0.81 [95% CI; 0.72, 0.89], all P < 0.001). Therefore, we conclude that eith er automated diagnostic system is accurate for CMV DNA quantitation.