PREVALENCE OF EXTENDED-SPECTRUM B LACTAMASES PRODUCING ENTEROBACTERIACEAE IN URINE SAMPLES FROM OUTPATIENTS IN A PRIVATE LABORATORY.

Bruna Dias (IPEC/Fiocruz); Rodrigo Almeida Paes (IPEC/Fiocruz); Fabio Brito (IPEC/Fiocruz)

The isolation number of Extended-Spectrum b lactamases (ESBL) producing Enterobacyeriaceae is increasing all over the world. Frequently, ESBL expression is associated with bacterial resistance to several antibiotics and dissemination by resistance plamids. There are several reports on the literature about ESBL isolation on patients admitted at the hospital. The aim of this study was to identify the occurence and prevalence of ESBL at the urinary trct of outpatients without recent hospital admissionin a private hospital and to check their sensitivity to the suggested antibiotics for ambulatorial use. During seven months in 2009, 413 Enterobacteriaceae strains were identified by phenotipical methods. Twenty-two of them (5.3%) were ESBL producers. These strains were identified by disk diffusion methods (sensitivity around 79-85%). The ESBL producers identified species were Escherichia coli (6/22), Klebsiella pneumoniae (6/22) and  Proteus spp (10/22). Fifty-nine percent of these strains were sensitive to sulfamethoxazole/thimethoprin, 82% to quinolones, 68% to amikacin, 54.5% to gentamicin, 36% to amoxacilin/clavulanic acid and 64.5% to polymyxin B. All Proteus strains were isolated from children under three years old, representing 64% of the patients of this work. All strains were sensitive to cabapenems (imipenem, meropenem and ertapenem). These antibiotcs are the first choice for the treatment of severe ESBL producing infection, therefore, their use on ambulatorial patients is more complex. Some authors descrvem the quinolonas may be regarded as the treatment of choice for complicated urinary tract infections due to ESBL-producing organisms, if there is not in vitro resistance to quinolonas. Due to the difficulties on antibiotical treatment and complexity of effective drugs used on outpatients, more studies on this field are of great importance and necessity.