Importance of screening in the prevention of emergence and spread of MDR bacteria

Background: Colonization is the presence of bacteria in the intestines, skin, nose, throat or anywhere in the human body without any signs of infection but with increased risk for spreading bacteria to other patients and the emergence of new infections. Screening of colonized patients is used as part of the prevention and control of multidrug-resistant (MDR) infections caused by agents such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis and multi-resistant Gram-negative bacteria. Material and methods: Data from 169 screened respondents hospitalized at the University Clinical Center Tuzla, between October 1, 2018, and May 1, 2019, were analyzed. Swabs were taken from nostrils, throat, axilla and groin area for all patients, and also from the anorectal area for 157 of them. Identification of MDR bacteria was done by phenotypical methods, according to the recommendations of EUCAST Clinical Breakpoint Table v.8.0, 2018. Results: Out of 169 patients, negative screening test results were found in 93 examinees (55.02%), and positive in 76 (44.97%). The largest number of patients undergoing screening was hospitalized in the Intensive Care Unit (Surgical Block), 73/169 (43.19%). The average screening time was 2.2 days or 53 hours. In 18/76 (23.68%) of patients with positive screening, prior to screening regular microbiological testing was done, and in the remaining 58/76 (76.3%) screening was performed first. Analyzing respondents with positive screening, 27 (35.53%) had negative findings during regular microbiological testing of different biological samples and for 49 (64.47%) different/same strains of MDR bacteria were isolated.Conclusion: Knowing the phenotypic profile of bacteria colonizing patients in intensive care units is a very useful tool in preventing their spread intra- and inter-hospitals.