Prevalence and mortality associated with multidrug-resistant infections in adult intensive care units in Argentina (PREV-AR)

Abstract

Data from low and middle-income countries (LMICs) on multidrug-resistant microorganisms (MDROs) in intensive care units (ICUs) are scarce. Working in several ICUs in Argentina, we sought to estimate the prevalence and characteristics of MDRO infections and carbapenemase-producing Enterobacterales (CPE) colonization. Mortality associated with MDRO infection was also evaluated. The study was a 24-hour point prevalence study conducted in 164 adult ICUs in Argentina between 24 November and 28 November 2023. The main study outcome was in-ICU mortality and secondary outcomes included the prevalence of MDRO infections, the prevalence of CPE colonization (defined as CPE recovered from a rectal swab), and ICU length of stay (LoS). Mixed effects modeling was used to identify risk factors for in-ICU mortality. Among 1,799 patients, 933 (51.9%) had a reported infection; 599 infections (64.2%) were classified as definite (i.e., with positive cultures) and 334 (35.8%) as probable infection (i.e., negative cultures but signs of infection). Of the 933 patients with infection, 273 (29.2%) had an MDRO recovered with 344 total MDRO cultures recovered. Non-MDRO was recovered from 326 (34.9%) of the 933 patients. Among definite infections, 45.5% (273/599) were due to MDRO with an overall prevalence of MDRO of 15.1% (273 patients with MDRO infections/1,799 patients). CPE colonization, defined as a positive rectal swab taken during the incident hospitalization, occurred in 420/1,696 (24.7%) patients. The most frequent MDRO infection was ventilator-associated pneumonia (100/344; 29.1%). The most common MDRO recovered were carbapenem-resistant Acinetobacter baumannii and CPE (98/344, 28.5% each). In-ICU mortality was 27.1% (487/1,799); independent predictors were age (odds ratio [OR] 1.01 [1.00-1.02], P = 0.003), MDRO infection (OR 1.65 [1.18-2.43], P = 0.012), probable infection (OR 1.41 [0.97-2.04], P = 0.073), sepsis-related organ failure assessment (SOFA) score (OR 1.18 [1.13-1.23], P = 0.000), and hospital-acquired pneumonia (OR 1.84 [1.12-3.01], P = 0.016). Mortality also varied significantly by hospital (P < 0.001). LoS was significantly longer in patients with MDRO infections, 30.0 (interquartile range [IQR] 17-35) days vs 16.0 (IQR 8-33) in non-MDRO, P < 0.0001. Among 1,799 ICU patients in an LMIC, the prevalence of MDRO infection and CPE colonization was high. The presence of an MDRO infection was associated with increased mortality and prolonged ICU LoS.CLINICAL TRIALSThis study is registered with Clinicaltrials.gov as NCT06574776.

Keywords: Argentina; adult intensive care units; carbapenem-resistant Enterobacterales; colonization; hospital infections; mortality; multidrug resistance; prevalence.

Fig 1

Flow diagram of the study. Each local institutional review board (IRB) defined the requirement for informed consent.

Fig 2

Localization of infections and microorganisms isolated. (A) VAP, ventilator-associated pneumonia; CRBSI, catheter-related bloodstream infection; IA, intra-abdominal infection; CR-UTI, catheter-related urinary tract infection; PBI, primary bacteremia; HAP, hospital-acquired pneumonia. (B) CRAB, carbapenemase-producing Acinetobacter baumannii; CPE, carbapenemase-producing Enterobacterales; ESBL, extended spectrum β-lactamase-producing microorganisms; MRSA, methicillin-resistant Staphylococcus aureus; DT-PAE, difficult-to-treat Pseudomonas aeruginosa; VRE, vancomycin-resistant Enterococci. (C) E. coli, Escherichia coli; KESC, group including Klebsiella, Enterobacter, Serratia, and Citrobacter; S. aureus, Staphylococcus aureus; P. aeruginosa, Pseudomonas aeruginosa; SCN, Staphylococcus coagulase-negative; S. pneumoniae, Streptococcus pneumoniae; S. pyogenes, Streptococcus pyogenes.