Bacterial/fungal infection in hospitalized patients with COVID-19 in a tertiary hospital in the Community of Castilla y León, Spain.

Introduction: Bacterial/fungal coinfection and superinfections contribute to the increased morbi-mortality of viral respiratory infections (RIs). The main objective of this study was to determine the incidence of these infections in hospitalized patients with COVID-19.

Method: Retrospective observational study of all patients admitted for COVID-19 and bacterial/fungal infections at the Hospital Clínico Universitario of Valladolid, Spain (March 1-May 31, 2020). Demographic, clinical and microbiological data were compared based on Intensive Care Unit (ICU) admission and predictors of mortality by were identified using multivariate logistic regression analyses.

Results: Of the 712 COVID-19 patients, 113 (16%) presented bacterial/fungal coinfections or superinfections. Their median age was 73 years (IQR 57-89) and 59% were men. The profiles of ICU patients (44%) included male, SARS-CoV-2 pneumonia, leukocytosis, elevated inteleukin-6, with interferon β-1b and tocilizumab and superinfection (p < 0.05). Coinfections were diagnosed in 5% (39/712) patients. Most common pathogens of respiratory coinfection (18) were Streptococcus pneumoniae (6) and Staphylococcus aureus (6). Superinfections were detected in 11% (80/712) patients. Urinary (53) and RI (39) constituted the majority of superinfections Acinetobacter baumannii multidrug-resistant was the main agent of IR and bacteremia. An outbreak of A. baumannii contributed to this result. Three patients were considered to have probable pulmonary aspergillosis. Mortality was higher in UCI patients (50% vs. 29%, p = 0.028). The predictive factors of mortality included being a male with various comorbidities, SARS-CoV-2 pneumonia, bacteremia and superinfections from A. baumannii.

Conclusion: The outbreak of A. baumannii was a determining factor in the increases of the incidence of infection and the morbi-mortality of ICU patients.