Esbl incidence and plasmid antimicrobial resistance

Abstract

Gram-negative bacilli resistance has been a cause for concern in Intensive Care Units (ICUs) and clinical laboratories. Resistance to cephalosporins and monobactams is associated with the production of enzymes known as beta-lactamases, which are of own by plasmids. This study’s objective was to determine the incidence of ESBL-producing bacteria in ICUs in the city of Goiânia Brazil. The methods evaluate the presence of plasmids in bacteria that were known to produce ESBL and as well as to verify the antibiotics re sistance conferred by the plasmids. The isolates were tested using antibiotics diffusion disk by Kirby-Bauer method, for ceftriaxone, ceftazidime, aztreonam and cefepime drugs. The plasmid DNA was extracted using Flexiprep Pharmacia Kit and cleaved with Eco R1, Bam HI and Pst I enzymes. The results showed that from the 200 strains analyzed, 74.5% were found to bacteria. From these, 21.5% were identified as Klebsiella sp. from which 8% were ESBL positive. The data show that 52.4% of the enterobacteriaceae were resistant to carbapenems, among the carbapenems studied, imipenem represented 97 (65.1%) and meropenem represented 95 (63.75%); 46.3% were cefepime sensitive. Suggesting that almost half of the bacteria presented resistance to some of the antibiotics tested. Almost all samples with plasmid presented countless number of colonies. However, few species presented plasmid, suggest ing with the bacterial resistance may be induced by chromosomal factor. Of the samples studied, 10.74% were ESBL-positive, this percentage resistance was suggested by beta-lactamase production.