The Usefulness of PCR and Early Antigen Immunostaining as a Rapid Identification Method of Cytomegalovirus Infection

Shin, Hea Jung; Kim, Hyun Kyung; Kim, Hyon Suk

Abstract

BACKGROUND: Cytomegalovirus infection is an important cause of morbidity and mortality after organ transplantation. Thus, rapid, sensitive and specific laboratory test, such as CMV antigenemia assay and polymerase chain reaction (PCR) is necessary to determine a patient's risk of CMV disease and to monitor the effectiveness of antiviral therapy. We compared the results of CMV-PCR and CMV early antigen immunostaining (CMV-EA) with CMV-specific IgM antibody to evalutate clinical usefulness for the early diagnosis of CMV infection and monitoring of antiviral therapy.
METHODS
We analyzed 170 samples submitted for CMV tests between September 1995 and April 1996 in Yonsei University College of Medicine Severance Hospital. CMV-PCR and CMV-EA were performed with buffy coat cells and detection of CMV-specific IgM antibody was performed by enzyme-linked fluorescent assay (ELFA).
RESULTS
One hundred and seventy samples of 159 patients were tested and analyzed. The concordance rate of CMV-PCR, CMV-EA and CMV-specific IgM in the same blood sample was 75.3%. The total incidence of CMV disease was 2.5%. The sensitivity and specificity based on the patients' clinical status of PCR were 100% and 91.6% respectively. In CMV-EA immunostaining method, they were 75.0% and 100% respectively. And, for CMV-specific IgM antibody ELFA, the sensitivity was only 50.0% and the specificity was 96.4%.
CONCLUSIONS
CMV-PCR and CMV-EA immunostaining are reliable methods as rapid early detection of CMV infection. The sensitivity and specificity are very high comparing to CMV- specific IgM antibody. It could also be concluded that they have advantages not only for early diagnosis but also monitoring or follow-up of a therapeutic course as quantitative assays.