The adverse impact of cytomegalovirus infection on intensive care units outcomes in critically ill COVID-19 patients: a single-center prospective observational study

Purpose To assess the incidence and clinical impact of CMV infection in critically ill COVID-19 patients, examining ICU and hospital mortality, and length of hospital stay. Methods In this single-center, prospective observational study (March 2020 - September 2022), 431 patients with COVID-19 pneumonia and moderate to severe ARDS were included. An active CMV surveillance protocol was implemented, analyzing CMV DNA in plasma and bronchoalveolar lavage (BAL). Clinical characteristics and outcomes were compared between CMV-COVID co-infected patients and those without CMV reactivation. Results CMV-COVID co-infection was detected in 14.8% (64/431) of the cohort. Patients with CMV-COVID co-infection exhibited significantly higher ICU mortality (43.8% vs. 13.6%; p < 0.001) and hospital mortality (48.4% vs. 13.6%; p < 0.001) compared to patients without CMV. CMV infection was an independent predictor of hospital mortality (OR 4.91; 95% CI 2.76-8.75; p = 0.019). Earlier CMV reactivation was associated with an increased risk of hospital mortality (HR = 0.94; 95% CI: 0.90-0.98; p = 0.003). Additionally, CMV-COVID patients had a higher incidence of ICU-acquired infections and a prolonged hospital stay. Conclusions In critically ill patients with SARS-CoV-2 pneumonia, CMV infection was frequently observed, and associated with increased ICU and hospital mortality. CMV co-infection correlated with a higher incidence of ICU-acquired bacterial and fungal infections and prolonged hospital stays. This emphasizes the importance of early CMV monitoring upon ICU admission, as timely detection and intervention could potentially mitigate its impact on patient outcomes.