Minimum Inhibitory Concentration of Cefotaxime by E-test Method on Klebsiella in Gorgan

Background and objectives: the increasing use of antibiotics, especiallythe third generation cephalosporins, is an important factor in the spread ofantibiotic resistance in bacteria. The main reason for the development ofresistance phenotype such as Extended Spectrum Beta Lactamas (ESBL) isthe extensive use of broad-spectrum cephalosporins. In phenotypic survey,the Phenotyping confirmatory test and the minimum inhibitoryconcentration (MIC) are used. In this study, the prevalence of the isolatesresistant to third generation cephalosporin (cefotaxime) was determinedbased on MIC.Material and Methods: form September 2010 to September 2011, 75isolates of Klebsiella pneumoniae were collected from the infections ofinpatients and outpatients, referred to state and private laboratories ofGorgan. For all of the Klebsiella pneumoniae strains, MIC determinationusing E-test (company Liofilcheme-Italy) was performed.Results: According to the MIC results, 26 samples (34.6%) are resistant tocefotaxime; 22 isolates are completely resistant to concentration of 256μg.Conclusion: Because of the importance of risk of becoming ESBL, furtherstudies are needed to clarify the ESBL in the region.Keywords: ESBL, MIC, Klebsiella pneumoniae, Cephalosporin