Bacterial coinfections were found to be common among patients hospitalized with COVID-19 infection, with most acquired during hospital admission. These study results were published in Journal of Hospital Infection
In a retrospective study, researchers reviewed electronic health records of patients with laboratory-confirmed COVID-19 infection who were hospitalized at 3 hospitals in Serbia from January 2021 to February 2022. The researchers assessed the prevalence, etiologies, and antibiotic resistance patterns of bacterial infections occurring after the onset of COVID-19 infection. The primary outcome was in-hospital mortality; secondary outcomes included invasive mechanical ventilation. Isolated bacteria were classified using VITEK2, analytical profile index procedure, and MALDI-TOF. The antimicrobial profile of the bacteria was determined through the disk diffusion method, gradient test, VITEK2 system, or broth microdilution test. Chi-squared and Fisher tests were used for possible associations of normal variables.
Among 6478 study patients, 68.7% were older than 65 (mean age, 68.6) years, and 54.7% were men. A total of 834 (12.9%) patients had bloodstream infections (BSIs) and/or bacterial coinfections, 57.6% of whom had monomicrobial infections.
Of patients with BSIs and respiratory infections, the most commonly isolated pathogens among patients with were Klebsiella pneumoniae (47%)and Acenitobacter baumannii (75.8%), respectively. Hospital-acquired infections accounted for 11.5% of bacterial infections overall, with pneumonia (n=240) and BSIs (n=268) being the most common. Gram-negative bacterial infections were more commonly observed among the patient population than gram-positive infections (69.3% vs 30.7%, respectively).
Multidrug-, extensively drug-, and pandrug-resistant bacterial pathogens accounted for 24.2%, 37.9%, and 12.8% of all infections, respectively. Of note, pandrug-resistant bacterial pathogens were isolated from only patients with hospital-acquired infections.
Ventilator-associated pneumonia occurred among 95% of intubated patients with bacterial coinfections (n=350). Of all patients with COVID-19 and bacterial coinfection, 675 (80.93%) had severe COVID-19 infection.
The rate of in-hospital mortality rate was 51.6% overall and 55.3% for patients older than 60 years. Mortality was significantly more likely among patients older than 60 years who were infected with at least 3 pathogens (P <0.05). Overall, 91.7% of patients who required invasive mechanical ventilation died.
Limitations of this study include its retrospective design and the lack of data on COVID-19 vaccination status and use of antibiotics and corticosteroids.
According to the researchers “Our results add to the growing evidence that existed pre-COVID-19 that infection prevention and control (IPC) should be focused on MDR bacteria and C. difficile, as well as on patients undergoing invasive mechanical ventilation.”
Gajic I, Jovicevic M, Popadic V, et al. The emergence of multi-drug-resistant bacteria causing healthcare-associated infections in COVID-19 patients: a retrospective multi-centre study. J Hosp Infect. 2023;137:1-7. doi:10.1016/j.jhin.2023.04.013