ICU-Acquired Superinfections Before And During The COVID-19 Pandemic: Similarities And Differences

During the COVID-19 pandemic, intensive care units (ICUs) experienced a surge in patients with viral pneumonia, often leading to acute respiratory failure. A global rise in ICU superinfections was observed; however, it remains unclear whether the extensive use of broad-spectrum antibiotics, corticosteroids, and immunosuppressants contributed to this rise.

We aim to identify clinical factors associated with these superinfections while analyzing epidemiologic patterns of superinfections in two different periods.

We conducted a retrospective study comparing ICU patients admitted between January 2016 and December 2018 (control group) with those admitted due to hypoxemic respiratory failure from SARS-CoV-2 between September 2020 and February 2022. Clinical characteristics were analyzed after propensity score matching, and a subsequent multivariate analysis was conducted on the COVID-19 population to identify independent risk factors for superinfections.

1456 patients were identified in the pre-COVID group and 164 in the COVID-19 group. The mean age was similar (64 years), but the pre-COVID-19 group was sicker. After matching, 427 pre-COVID-19 and 163 COVID-19 patients were analyzed. COVID-19 patients experienced higher superinfection rates (42 % vs. 12 %, p < 0.001), were more obese, and had greater exposure to antibiotics and corticosteroids. After multivariate analysis of the COVID-19 population, ICU length of stay (OR=1.09, p = 0.01) and mechanical ventilation (OR=5.05, p = 0.008) were independent risk factors for superinfections.

Increased superinfection rates in COVID-19 patients were linked to mechanical ventilation and prolonged ICU stays, potentially influenced by MDR infections linked to antibiotics and corticosteroids. Further investigations are needed to establish causality.