Secondary Bacterial Infections and Antimicrobial Resistance in COVID-19: Comparative Evaluation of Pre-Pandemic and Pandemic-Era, A Retrospective Single Center Study

Abstract Purpose: In this study, we aimed to evaluate the epidemiology and antimicrobial resistance (AMR) patterns of bacterial pathogens in COVID-19 patients and to compare the results with control groups from the pre-pandemic and pandemic era.Methods: Microbiological database records of all the COVID-19 diagnosed patients in the Ege University Hospital between March 15, 2020, and June 15, 2020, evaluated retrospectively. Patients who acquired secondary bacterial infections (SBIs) and bacterial co-infections were analyzed. Etiology and AMR data of the bacterial infections were collected. Results were also compared to control groups from pre-pandemic and pandemic era data.Results: In total, 4,859 positive culture results from 3,532 patients were analyzed. Fifty-two (3.59%) patients had 78 SBIs and 38 (2.62%) patients had 45 bacterial co-infections among 1,447 COVID-19 patients. 22/85 (25.88%) patients died who had bacterial infections. The respiratory culture-positive sample rate was 39.02% among all culture-positive samples in the COVID-19 group. There was a significant decrease in extended-spectrum beta-lactamase-producing Enterobacterales (8.94%) compared to samples from the pre-pandemic (20.76%) and pandemic era (20.74%) (p=0.001 for both comparisons). Interestingly, Acinetobacter baumannii was the main pathogen in the respiratory infections of COVID-19 patients (%9.76) and the rate was significantly higher than pre-pandemic (3.49%, p<0.002) and pandemic era control groups (3.11%, p<0.001).Conclusion: Due to the low frequency of SBIs reported during the ongoing pandemic, a more careful and targeted antimicrobial prescription should be taken. While patients with COVID-19 had lower levels of ESBL producing Enterobacterales, the frequency of MDR A. baumannii is higher.