Background: Nosocomial infections are a major health prob- lem, with high health and economic burden. Numerous strategies have been developed to prevent and diminish them. One important risk factors to acquire nosocomial infections is being hospitalized in intensive care units (ICU). Multidrug-resistant Gram-negative bac- teria (MDR-GNB) are more frequent among these infections, and patient’s gastrointestinal tract is an important reservoir.
Methods & Materials: We analyzed 3 periods of prospective studies were gastrointestinal colonization was investigated and we looked for clinical infections and its etiology once the patient was discharged from the ICU. The studies were carried out in Hospital de Clínicas, a university referral hospital in 2010-2011, 2014-2015 and 2016-2017. Patients with more than 48 hours of invasive mechan- ical ventilation were included. Data from patients were collected and later nosocomial infections in moderate care were registered. All patients included were followed until death or discharge. Pha- ryngeal and rectal swabs were taken before ICU discharge and were cultured in MacConkey Lactose with and without 1 g/ml ceftriax- one.
Results: 227 patients were included, 31 clinical isolates from later nosocomial infections were found in Hospitals records, and 10 of these presented the same bacteria in clinical and swabs isolates. This data shows that approximately 14% (31/227) of patients had a later nosocomial infection with at least one clinical isolate and that 30% (10/31) of these were colonizing patient’s gastrointestinal tract.
Conclusion: Data reviewed supports the fact that knowing the “colonization status” at ICU discharge helps predicting the etiology of later nosocomial infections in the third part of cases. Given the difficulty for microbiology diagnose in many nosocomial infections, we think that empirical treatment could be based in results of rectal and pharyngeal swabs. We believe that more nosocomial infections are diagnosed but no clinical isolate is recovered. To sort these lim- itations, we continue enrolling patients in our case-control study.
