Multidrug colonization and infections in ICU: Organization and structural variables. A prospective cohort study (RESIST STUDY)

Introduction: Healthcare-acquired infections (HAIs) represent a significant issue, exacerbated by the spread of multi-drug resistant strains, which pose a global public health problem and present new challenges for clinicians. This concern is particularly critical in Intensive Care Units (ICUs), where critically ill patients are at high risk for nosocomial infections, leading to considerable morbidity, mortality, and costs. Beyond the patient's own susceptibility, research increasingly demonstrates that contaminated surfaces and equipment significantly contribute to pathogen transmission in ICUs with healthcare workers' hands constituting the primary vehicle for cross-transmission. Other factors playing a role include inadequate environmental cleaning, ICU structural features like overcrowding and high patient turnover, and antibiotic misuse. Additionally, patient-specific factors, such as previous colonization, recent surgeries, transplantation, hospitalization, comorbidities, and poor functional status, further elevate the risk of HAIs. Objectives/ Methods: The RESIST study is a prospective observational multi-center international cohort study that aims to investigate the prevalence of multidrug-resistant (MDR) colonizations and infections in intensive care units (ICUs). The study includes adult patients admitted to ICUs for at least 48 hours over a period of three months, excluding those with post-operative monitoring or ICU readmission during the same hospital admission. Results: These preliminary results are based on a sample of 34 patients. The incidence of colonizations acquired during hospitalization was 39.3% while the one of new infections during ICU stay was 41.2%. Concerning resistant pathogens, they constituted the 27.3% among the microorganisms isolated in new onset colonizations and 33.3% among microorganisms isolated in new onset infections. The most common resistant isolates found were strains of Acinetobacter spp., Escherichia Coli, Pseudomonas Aeruginosa, and Klebsiella Pneumoniae, confirming the rising trend of gram-negative MDRO infections in ICU over gram-positive ones. Conclusion: No statistically significant association was found between patient characteristics and colonization at admittance, nor between room design and colonizations/infections during ICU stay. Also, conclusions cannot be drawn because of the limited sample size; the study is ongoing and additional data are needed. Nevertheless, the study underlines the increasingly emerging problem of MDR ICU-acquired infections, which is particularly concerning among critically ill patients. Once more, the most powerful weapon seems to be prevention; thus, our attention should be focused on new hygienic measures, the implementation of antimicrobial stewardship and the use of rapid diagnostic tests usage.