Isolation of CTX-M1, CTX-M2, CTX-M3 Genes Producing Extended-Spectrum Beta-Lactamase in Clinical Samples of Salmonella typhimurium

objectives:the purpose of this study was to isolate ctxm1 and ctxm3 genes producing extendedspectrum betalactamase (esbl) from clinical samples of salmonella typhimurium isolated from poultry in zabol, iran. methods:all the strains were cultured and identified in a clinical microbiology laboratory and were recovered from blood and urine cultures. the in vitro presence of esbl was confirmed with clinical and laboratory standard institute double disc and pcr methods for ctxm1 and ctxm3. results:the results of this study showed that salmonella typhimurium samples were resistant to ampicillin (41.66%), gentamycin (0%), cefazolin (0%), amoxiclav (10%), and azithromycin (5%) antibiotics. conclusions:the widespread use of esbl antibiotics has increased the spread of esbl enzymes in iran and throughout the world and the use of these antibiotics is becoming more and more limited. therefore, the complete identification of esbl by experiments, the restriction of the use of betalactam antibiotics and the use of betalactamase inhibitors can maintain the efficacy of betalactam antibiotics as much as possible.