Factors associated with cross infections in COVID-19 patients in a Tunisian intensive care unit: a longitudinal study

Superinfections in intensive care units (ICU) are usually due to multidrug resistant microorganisms and impact the patient prognosis. The aim of this study was to identify risk factors associated with cross infections in COVID-19 ICU patients.

This was an observational longitudinal study performed in the intensive care unit of University Hospital Sahloul. All patients diagnosed with COVID-19 and admitted to ICU were included. The data were extracted prospectively from medical records and from the microbiology laboratory chart. To identify factors associated with cross infections among COVID-19 patients, binary logistic regression model was used. Significant p value was set at 0.05.

A total of 319 patients were included with a mean age of 62 ± 13 years old. Average length of stay was 9 ± 7 days. A total of 196 cross infections were diagnosed and 102 (32%) patients had at least one cross infection. Ventilator-acquired pneumonia and bacteremia were diagnosed in 62% and 52% of patients. The mean time to onset of the first cross infection was 8 ± 5 days. A total of 206 strains were responsible for cross infections with a majority of Acinetobacter baumannii (53,9%). Independent risk factors associated with cross infections in COVID-19 ICU patients were age > 75 years old (RR = 2.61; CI_95%[1.11-6.13]), chronic obstructive pulmonary disease (COPD) (RR = 0.15; CI_95%[0.03-0.69]) and venous catheter use (RR = 14.8, CI_95%[5.21-42.05]). Hypertension was the only mortality associated factor on multivariate analysis (RR = 7.84; CI_95%[1-63.85]).

In COVID-19 ICU patients, the prevalence of cross infection was 32% within 8 ± 5 days. The main microorganism was Acinetobacter baumannii. Independent risk factors associated with cross infections were advanced age, and venous catheter use.