Bacterial infections in critically ill patients with SARS-2-COVID-19 infection: results of a prospective observational multicenter study

Abstract

Purpose: To investigate the prevalence, incidence and characteristics of bacterial infections and their impact on outcome in critically ill patients infected with COVID-19.

Methods: We conducted a prospective observational study in eight Italian ICUs from February to May 2020; data were collected through an interactive electronic database. Kaplan-Meier analysis (limit product method) was used to identify the occurrence of infections and risk of acquisition.

Results: During the study period 248 patients were recruited in the eight participating ICUs. Ninety (36.3%) patients developed at least one episode of secondary infection. An ICU length of stay between 7 and 14 days was characterized by a higher occurrence of infectious complications, with ventilator-associated pneumonia being the most frequent. At least one course of antibiotic therapy was given to 161 (64.9%) patients. Overall ICU and hospital mortality were 33.9% and 42.9%, respectively. Patients developing bacteremia had a higher risk of ICU mortality [45.9% vs. 31.6%, odds ratio 1.8 (95% CI 0.9-3.7), p = 0.069] and hospital mortality [56.8% vs. 40.3%, odds ratio 1.9 (95% CI 1.1-3.9), p = 0.04].

Conclusion: In critically ill patients infected with COVID-19 the incidence of bacterial infections is high and associated with worse outcomes. Regular microbiological surveillance and strict infection control measures are mandated.

Keywords: COVID-19; Co-infection; Critically ill patients; Secondary bacterial infection.

Fig. 1

Severe infection type (bacteremia, VAP, UTI, and combinations) stratified by days following ICU admission. Numbers represent occurrence of each variable

Fig. 2

Kaplan–Meier curves for hospital survival stratified by development (or not) of a bacteremia and b ventilator-associated pneumonia. Numbers represent occurrence of each variable