Evaluation of new quantitative assays for diagnosis and monitoring of cytomegalovirus disease in human immunodeficiency virus-positive patients

Cobas Amplicor CMV Monitor (CMM) and Quantiplex CMV bDNA 2.0 (CMV bDNA 2.0) , two new standardized and quantitative assays for the detection of cytomeg alovirus (CMV) DNA in plasma and peripheral blood leukocytes (PBLs), respec tively, were compared to the CMV viremia assay, pp65 antigenemia assay, and the Amplicor CMV test (P-AMP). The CMV loads were measured in 384 samples from 58 human immunodeficiency virus (HIV) type 1-infected, CMV-seropositiv e subjects, including 13 with symptomatic CMV dis ease. The assays were hig hly concordant (agreement, 0.88 to 0.97) except when the CMV load was low. Quantitative results for plasma and PBLs were significantly correlated (Spe arman rho = 0.92). For PBLs, positive results were obtained 125 days before symptomatic CMV disease by CMV bDNA 2.0 and 124 days by pp65 antigenemia a ssay, whereas they were obtained 46 days before symptomatic CMV disease by CMM and P-AMP. At the time of CMV disease diagnosis, the sensitivity, speci ficity, and positive and negative predictive values of CMV bDNA 2.0 were 92 .3, 97.8, 92.3, and 97.8%, respectively, whereas they were 92.3, 93.3, 80, and 97.8%, respectively, for the pp65 antigenemia assay; 84.6, 100, 100, an d 95.7%, respectively, for CMM; and 76.9, 100, 100, and 93.8%, respectively , for P-AMP. Considering the entire follow-up, the sensitivity, specificity , and positive and negative predictive values of CMV bDNA 2.0 were 92.3, 73 .3, 52.1, and 97.1%, respectively, whereas they were 100, 55.5, 39.4, and 1 00%, respectively, for the pp65 antigenemia assay; 92.3, 86.7, 66.7, and 97 .5%, respectively, for CMM; and 84.6, 91.1, 73.3, and 95.3%, respectively, for P-AMP. Detection of CMV in plasma is technically easy and, despite its later positivity (i.e., later than in PBLs), can provide enough information sufficiently early so that HIV-infected patients can be effectively treate d. In addition, these standardized quantitative assays accurately monitor t he efficacy of anti-CMV treatment.