Methicillin-Resistant Staphylococcus aureus and Other Multidrug-Resistant Colonizations/Infections in an Intensive Care Unit: Predictive Factors

Abstract

Introduction and Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is the most prevalent pathogen causing nosocomial infections in hospitals and health centers. This work is an effort to understand the epidemiology of MRSA and other multidrug-resistant pathogens in an intensive care unit (ICU) and to analyze characteristics that might determine the risk of MRSA colonization/infection in this unit. Method: An observational, 1-year prospective longitudinal study was conducted to obtain information about MRSA and other multidrug-resistant colonizations/infections. The study was conducted with ICU patients with an artificial airway. Data were obtained from the National Study of the Control of Nosocomial Infections in Intensive Care Units database. Results: MRSA colonization was highly prevalent (33%); however, other pathogens like gram(−) Bacillus showed a higher infectious potency. Acute Physiology and Chronic Health Evaluation (APACHE-II) score >15 and hospital stay of >4 days were the main variables that significantly predicted the risk of developing MRSA colonization ( p < .001 in both cases). Moreover, the presence of MRSA increased the risk of developing a second multidrug-resistant colonization/infection, especially with methicillin-resistant Pseudomona. Discussion: The high prevalence of MRSA emphasizes the need to continue studying risk factors for MRSA colonization/infection, which may allow early identification of this pathogen. Therefore, we propose the use of the APACHE-II score and length of hospital stay to predict increased risk of MRSA colonization. Awareness of the heightened risk in particular patients could lead to early detection and prevention.