Comparison of plasma polymerase chain reaction and pp65-antigenemia assay in the quantification of cytomegalovirus in liver and kidney transplant patients.

Abstract

Cytomegalovirus (CMV) is a significant problem in transplantation. The antiviral treatment is based on the clinical symptoms and the rapid laboratory diagnosis. Although polymerase chain reaction (PCR) methods have already been widely used, the clinical correlation of the findings is not clear. The objective of this study was to investigate the usefulness of a quantitative plasma PCR test and compare it with the pp65-antigenemia test in the detection of clinically significant CMV infections in liver and kidney transplant patients. The clinical material consisted of 253 consecutive blood samples was tested using a quantitative polymerase chain reaction test, Cobas Amplicor CMV Monitor (Roche) and pp65 antigenemia assay. Plasma was used for PCR and leucocytes were used for the antigenemia test. CMV was detected in 89 out of 253 blood samples by one or both methods. PCR detected 78 (range 274-165000 copies/ml) and pp65 antigenemia test 79 (range 1-1500 positive cells/50000) of the positive findings. The sensitivity and specificity of PCR test was 86 and 94%, respectively. The PCR detected all clinically significant CMV infections (>10 positive cells in pp65 test) and infections which required antiviral treatment. In addition, the correlation between the two tests was almost linear. The quantitative PCR appears to be a suitable alternative to diagnose and monitor CMV infections in transplant patients.