Secondary infections in critically ill patients admitted with COVID-19 in Bogotá, Colombia. Observational cohort study

Abstract

Introduction: The presence of secondary infections in critically ill patients and antibiotic resistance are often determining factors in the clinical evolution of these patients. Objective: To describe the pathogens isolated in blood cultures and tracheal secretion cultures in ICU patients with COVID-19 and to evaluate the association between the presence of secondary infections and 60-day mortality. Methods: Retrospective analytical cohort study conducted in 273 adults admitted to the ICU with COVID-19 at the Subred Integrada de Servicios de Salud del Sur - Hospital El Tunal, Bogotá, Colombia between April and December 2020. Data from records of blood or tracheal secretion cultures were collected . A bivariate analysis was performed using a Cox proportional-hazards regression model to assess the association between the development of secondary infections and 60-day mortality. Results: At least one positive blood culture was reported in 96/511 patients (18.8%). Of the 214 blood cultures performed within 48 hours after ICU admission, 7.7% were positive. A total of 127 germs were isolated from blood cultures - mostly gram-negative bacteria (61.4%) - followed by fungi (25.2%). Additionally, 39.5% were multidrug-resistant, and carbapenem resistance was the most common antibiotic resistance pattern (33.3% of all gram-negative bacteria isolates). Finally, in this cohort, the presence of secondary infections was not associated with 60-day mortality (HR: 1.012, 95%CI: 0.721-1.420; p= 0.946). Conclusions: Although the prevalence of superinfection was moderately high, the prevalence of coinfection was low. Gram-negative bacteria were predominant, and almost one third of the germs were multidrug-resistant.