Evaluation by polymerase chain reaction of cytomegalovirus reactivation in intensive care patients under mechanical ventilation.

Abstract

The study was undertaken to determine if critically ill patients under mechanical ventilation could reactivate latent cytomegalovirus (CMV) in either lung or blood. Prospective study in critically ill patients was performed in a multidisciplinary intensive care unit in a university hospital. 23 non-immunocompromised, mechanically ventilated patients who were anti-CMV immunoglobulin G-positive. Ten immunocompromised patients with active CMV infection and 16 asymptomatic CMV seropositive non-immunocompromised patients constituted the positive and negative control groups. The presence of CMV in blood and bronchoalveolar lavage (BAL) was evaluated by both viral cultures and polymerase chain reaction (PCR). Thirty-seven blood and 22 BAL samples were investigated. Sequential samples were evaluated in 8 patients. For PCR, a 290 bp fragment in the first exon of the immediate early 1 gene was amplified. In order to exclude inhibitors of PCR amplification, a 268 bp fragment of the beta-globin gene was concurrently amplified in all samples. Viral cultures of blood and BAL were negative in all 23 non-immunocompromised, mechanically ventilated patients. Moreover, no CMV DNA could be amplified in blood BAL samples, whereas a beta-globin amplification was observed in all samples. In a series of 23 critically ill patients under mechanical ventilation who were seropositive for CMV, no reactivation of CMV in blood or lung was demonstrated.