ICU Admission Screening for Multidrug-Resistant Organism Colonization and Subsequent Infection Risk: A Pilot Study

Area of Science:

• Infectious Diseases
• Critical Care Medicine
• Epidemiology

Background:

• Multidrug-resistant organism (MDRO) colonization upon intensive care unit (ICU) admission is a potential risk factor for hospital-acquired infections (HAI).
• The independent predictive value of MDRO colonization for HAI risk requires further definition.

Purpose of the Study:

• To evaluate the association between MDRO colonization at ICU admission and the risk of developing HAI.
• To assess the predictive performance of MDRO screening, alone and combined with clinical variables, for HAI.

Main Methods:

• Retrospective observational study of 560 ICU admissions.
• Admission screening for extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales, carbapenem-resistant Enterobacterales (CRE), and vancomycin-resistant enterococci (VRE).
• Multivariable logistic regression and ROC/AUC analysis to assess associations with HAI and in-hospital mortality.

Main Results:

• MDRO screening was associated with increased HAI odds (OR 1.81, p=0.065), reaching significance in a sensitivity analysis for first admissions (OR 2.09, p=0.034).
• Carbapenem-resistant Enterobacterales (CRE) demonstrated the strongest adjusted association with HAI (OR 2.33, p=0.012).
• MDRO screening combined with clinical variables significantly improved HAI prediction (AUC 0.788) compared to screening alone (AUC 0.574).

Conclusions:

• MDRO admission screening shows an association with increased HAI risk, particularly for CRE colonization.
• While screening alone has limited predictive value, its combination with clinical factors enhances risk assessment.
• Further prospective studies are warranted to validate these findings and refine prediction models.