Cytomegalovirus infection in transplant recipients: Applications of PCR

Objective: Various laboratory methods for detection of cytomegalovirus (CMV ) are available, but all suffer from limited sensitivity and specificity or are prone to sampling errors. With the highly sensitive polymerase chain r eaction (PCR) active CMV infection is difficult to confirm, so schemes have been devised to improve the diagnostic significance of CMV PCR. Data Sourc es: Recent literature, including original articles by the authors, on labor atory diagnosis of CMV infection in transplant patients is reflected on. Se lection Criteria: CMV PCR applications in the transplant setting, particula rly renal transplantation, are discussed with respect to specific risks for CMV infection in this group of patients. Results: CMV PCR from leukocytes usually becomes positive earlier than antigenemia. Repeatedly positive qual itative PCR over time as well as quantitative PCR increase the predictive v alue far symptomatic CMV infection in seropositive transplant recipients, w ith PCR being less hampered by delayed sample processing than antigenemia. CMV PCR from leukocytes of healthy seropositive blood donors remains contin uously negative. To date PCR data an the role of CMV in graft rejection are controversial. Conclusions: Qualitative CMV PCR is best of all useful to screen seronegati ve transplant recipients. Quantitative PCR is superior to antigenemia when analyzing samples processed with delay. PCR screening of blood products for CMV is not reasonable The utility of PCR to recognize CMV-associated graft rejection is unclear.