Evaluation of susceptibilities of some pathogenic Bacteria to some routine antibiotics

Objectives: Nowadays increasing resistance of pathogenic bacteria against antibiotics is a worldwide challenge. Antibiotics are commonly used for treatment of infections caused by MDR (multiple drug resistance) pathogens in hospitals and clinics. So knowledge of the present susceptibility levels of pathogenic bacteria to different antibiotics is indicated. The aim of the present study was to evaluate the susceptibilities of some pathogenic bacteria to Kanamycin, Penicillin, Ciprofloxacin and Tetracycline.as routine antibiotics for treating bacterial infections.Materials and Methods: Tube double serial dilution method was used to determine minimum inhibitory concentrations (MIC) of 40 hospital/field and also standard isolates of four pathogenic bacteria namely: Staphylococcus aurous, Pseudomonas aeruginosa, Acinetobacter baumannii and Escherichia coli (each 10 isolates) against mentioned antibiotics.Results and Conclusion: According to the obtained results, the mean MICs of Kanamycin, Penicillin, Ciprofloxacin and Tetracycline for Staphylococcus aureus were 36, 700, 0.3and 3.2(µg/ml) respectively. For Pseudomonas aeruginosa the MICs values were 70, 9400, 0.4and 1100(µg/ml) respectively. For Acinetobacter baumannii the values were 500, 10000, 1and 1000(µg/ml) and for Escherichia coli the values were 1.8, 800, 0.3and 3.5(µg/ml) respectively. Ps. aeroginosa was more resistant to tested antibiotics than other Three examined bacteria. All examined isolates showed some degree of resistancy against examined antibiotics.