Aetiology and resistance of Staphylococcus spp. and Gram-negative bacilli isolated from ICUs’ surveillance culture
Antibiotic resistance; Surveillance; Intensive Care Units; Microbiota; Carbapenems
The existence of pathogens with high antimicrobial resistance, capable of being part of enteric and cutaneous microbiota, increases the risk of serious infections. Thus surveillance cultures are important to identify these microorganisms and minimize their propagation. This research used surveillance cultures to determine the presence of several resistance mechanisms existent in bacteria colonizing 114 patients admitted in Intensive Care Units (ICUs) for 7 or more days. For this purpose, manual methods of phenotypic identification, antimicrobial susceptibility and phenotypic tests for the indication of beta-lactamases’ production were used. From 110 isolated Sthaphylococcus spp., 89% (98 of 110) were resistant to Oxacillin. On the other hand, 43% (58 of 133) of Enterobacteriaceae were Extended Spectrum Beta-Lactamases (ESBL), 57.5% (23 of 40) of Pseudomanoas aeruginosa were AmpC and 81% (30 of 37) of Acinetobacter spp. were resistant to Carbapenems. Among the studied clinical variables, it was found a significant statistical association between the use of Carbapenems and colonization by bacteria resistant to these antibiotics. These really high indexes reflect the current epidemiological tendency of high resistant bacteria growth, making essential the implementation of surveillance measures, isolation and rationalization of antibiotic use to minimize the dissemination of these pathogens.