THE SURVEY OF ANTIBIOTIC RESISTANCE IN GRAM NEGATIVE BACILLI, ISOLATED FROM URINE CULTURE SPECIMENS, IMAM REZA HOSPITAL-KERMANSHAH.

Antimicrobial resistance among bacterial pathogens is a worldwide problem. The selection of initial treatment is made on an empiric basis and susceptibility testing is important to modify empirical therapy, especially for treatment of common bacterial pathogens. The aim of the present study was to determine the antimicrobial susceptibility of gram negative pathogens found in urine cultures. Materials & Methods: The study samples were all urine specimens submitted for culture in central laboratory of Imam Reza Hospital during a 12-month period during 2006-2007. All of the specimens were cultured on MacConky agar, blood agar and differential media for gram negative bacteria. After diagnosis and isolation of gram negative bacteria, proper inoculum was used for susceptibility testing. Susceptibility testing was done by disk diffusion test (Kirby-Bauer method) and interpreted according to NCCLS recommendation. Results: Of 10492 cultured urine samples, 1815 (17.29%) specimens had positive results, 1239(68.2%) cases were positive for gram negative bacteria and the most common pathogen was E.coli (66.3%). Antibiotic susceptibility results revealed that gram negative bacterial have the greatest susceptibility to imipenem (67.9%). The E.coli antibiogram profile showed the greatest resistance to ampicillin (91.6%) and cotrimoxazole (61.3%). Pseudomonas Sp. was an exception that resisted to all antibiotics except for imipenem (100%) and ciprofloxacin(69%). Conclusion: According to the results, it is apparent that an antimicrobial susceptibility test of bacteria differs by geographic region therefore, in order to confirm a diagnosis, Antibiotic resistance patterns of a community and empirical therapy must be considered.