Abstract:

Objective: To investigate the characteristics of antimicrobial resistance of Staphylococcus aureus strains producing β-
lactamase which were isolated from clinic in local hospitals. Methods: By using VITEK-32 automated microbiology system for identification of Staphylococcus, β- lactamase in Staphylococcus aureus was detected by Nitrocefin paper. Antimicrobial susceptibility was detected by the disk diffusion method. Results: Of 61 strains of Staphylococcus aureus, 13 strains produce β-lactamase and the rate of producing enzymes was 21.3%. The strains producing enzymes were most sensitive to Vancomycin and more sensitive to Levofloxacin. The resistant rate of ampicillin and pencillin G were 92.4% and erythromycin was 84.7%; clindamycin was 69.3%. Conclusions: The detection of β- lactamase in Staphylococcus aureus must be a normal item. The strains producing β- lactamase were highly resistant to penicillins and macrolides. Vancomycin must be the first choice in anti-infection caused by Staphylococcus aureus. Antibiotics should be chosen rationally under the guide of the microbial sensitivity test.

Key words: staphylococcus aureus,  β- lactamase, drug resistance