ACTA FAC. MED. NAISS. 2004; 21 (1): 37-42

Original article

ANTIMICROBIAL SUSCEPTIBILITY TO CERTAIN AGENTS AND THE PREVALENCE OF AN EXTENDED – SPECTRUM BETA LACTAMASES PRODUCING ISOLATES AMONG ENTEROBACTERIACEAE FROM VARIOUS CLINICAL SPECIMENS

    Snežana Mladenović-Antić, Branislava Kocić, Marina Dinić, Ljiljana Krivokapić, Gordana Ranđelović
    Institute of Public Health Nis

      SUMMARY

    Infections with multiply antibiotic resistant organisms cause significant morbidity and mortality. ESBL producing aerobic gram negative rods are resistant to the first, second and third generation cephalosporins, penicilins and monobactams, and may show simultaneous resistance to fluoroquinolones and aminoglicosides.
    The aim of this investigation was to evaluate antimicrobial susceptibility to selected antibiotics and to comprise the frequency of ESBL producing strains among the most common gram negative rods conducted during 2002. from different clinical specimens at the Institute of Public Health in Nis.
    One thousand and thirty two strains of Enterobacteriaceae were studied. Antimicrobial susceptibility was tested by the disk-diffusion method according the American National Committee for Clinical and Laboratory Standards (NCCLS) guidelines. Screening for detection for ESBL in Enterobacteriaceae was performed by the double-disk sinergy test (DDST).
    Antimicrobial resistance to beta-lactam antibiotics was: to ampicilin 65.7%, to cefalexin 61.24 %, to ceftriaxon 14.53%, and to cefotaxim 14.34%.    
    ESBL production was observed in 15.79%. The highest rates were for Klebsiella spp.52%, E.coli 17.4% and Enterobacter spp. 23%. Seventy- three percent of ESBL positive strains were nosocomial.
    The ESBL positive strains of Enterobacteriaceae are now emerging in our country. We have found an increase in the resistance of this strains to tested antibiotics.

    Key words: Enterobacteriaceae, antimicrobial susceptibility, exteded spectrum beta-lactamases