The aim of our systematic review was to investigate the association between CMV reactivation and outcomes in immunocompetent critically ill patients.


We searched electronic databases and grey literature for original studies and abstracts published between 1990 and October 2016. The review was limited to studies including critically ill immunocompetent patients. CMV reactivation was defined as positive PCR, pp65 antigenemia or viral culture from blood or bronchoalveolar lavage. Selected patient-centered outcomes included mortality, duration of mechanical ventilation, need for renal replacement therapy (RRT) and nosocomial infection. Health resource utilization outcomes included ICU and hospital lengths of stay.


Twenty-two studies were included. In our primary analysis, CMV reactivation was associated with increased ICU mortality [OR 2.55, 95% CI 1.87–3.47], overall mortality [OR 2.02, 95% CI 1.60–2.56], duration of mechanical ventilation [mean difference 6.60 days, 95% CI 3.09–10.12], nosocomial infection [OR 3.20, 95% CI 2.05–4.98], need for RRT [OR 2.37, 95% CI 1.31–4.31] and ICU length of stay [mean difference 8.18 days, 95% CI 6.14–10.22]. In addition, numerous sensitivity analyses were performed.


In this meta-analysis, cytomegalovirus reactivation was associated with worse clinical outcomes and greater health resource utilization in critically ill patients. It remains unclear, however, if CMV reactivation plays a causal role or if it is a surrogate for more severe illness.

Author notes

Corresponding Author: Dr. Philippe Lachance (plachanc@ualberta.ca)
Alternate Corresponding Author: Dr Wendy Sligl (wsligl@ualberta.ca) Department of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 2–124 Clinical Sciences Building, 8440 – 112th Street, Edmonton, Alberta, Canada, T6G 2B7, T. (780) 492–8311; F. (780) 492–1500;
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