Predictive value of cytomegalovirus DNA detection by polymerase chain reaction in blood and bronchoalveolar lavage in lung transplant patients

Despite promising results, the efficacy of polymerase chain reaction (PCR) for clinical management of cytomegalovirus (CMV) infection in transplanted patients is still controversial. A prospective study of CMV detection, with concurrent shell vial cultures and PCR in blood and bronchoalveolar lavage (BAL), was conducted in 13 lung transplant recipients, monitored for 15 months (range: 1-42 months). CMV DNA was detected by PCR amplification of a 406-bp fragment in the Us region and a 290-bp fragment in the immediate early region of the viral genome. When comparing PCR to viral culture, the sensitivity and specificity of CMV DNA detection were 100% and 65.7% in blood (n=122) and 100% and 75% in BAL (n=104). The positive and negative predictive values of PCR for a forthcoming diagnosis of CMV infection were 50% and 97% in blood, and 67% and 85% in BAL. Seventeen CMV infections were evaluated at the end of treatment: when PCR was still positive either in blood or BAL, CMV infection relapsed within 35+/-5 days; when PCR was negative, CMV infection relapsed after 142+/-57 days (P=0.01). Negative CMV detection by PCR strongly advocates against a forthcoming CMV infection. PCR assay seems to be a good predictor for early recurrence of CMV infection, and would be useful for monitoring the response to antiviral therapy.