Use of nested polymerase chain reaction for the detection of cytomegalovirus in clinical specimens.

ABSTRACT

BACKGROUND & OBJECTIVES: Since fluorescent antibody test (FAT) has low sensitivity in the rapid detection of cytomegalovirus (CMV) in clinical specimens, a nested polymerase chain reaction (nPCR) to detect the CMV-DNA was evaluated. METHODS: nPCR and FAT were carried out to detect CMV in single specimens from 104 patients and dual specimens from 32 patients with suspected active CMV infection. Of the 136 patients, 3 were HIV positive. RESULTS: CMV was detected by FAT alone in 3 (1.8%) and FAT and nPCR in 16 (9.5%) specimens and by nPCR alone in 84 (50.0%) specimens from 74 (54.4%) patients. nPCR increased the clinical sensitivity by 50.0 per cent in the specimens and 54.4 per cent in the patients (McNemar test, P < 0.001). Urine was found to be the ideal specimen for the detection of CMV as the detection rate in the urine was statistically higher (McNemar test, P < 0.05) than in the blood. Buffy coat and plasma samples from 35 normal blood donors were subjected to nPCR and ELISA respectively. CMV-DNA was not detected in any of the samples while anti-CMV antibodies were detected in all of them. INTERPRETATION & CONCLUSION: The results showed that presence of CMV-DNA in the specimen indicates active infection and nPCR is a rapid, sensitive, specific and a more reliable diagnostic tool than FAT.