Antibiotic resistance and molecular epidemiology profile of methicillin-resistant Staphylococcus aureus
Objective To investigate antibiotic resistance and molecular epidemiology profile of methicillin-resistant Staphylococcus aureus (MRSA) at Peking Union Medical College Hospital in Beijing. Methods Antibiotic resistance of 165 MRSA strains isolated from clinical specimen recovered in 2002 was determined by agar dilution and agar diffusion. Pulsed-field gel electrophoresis (PFGE) was used to type the chromosome DNA of MRSA isolates at intensive care unit (ICU) and respiratory care unit (RCU) wards. Results All of MRSA isolates were susceptible to vancomycin and teicoplanin. The resistance to levofloxacin, tetracycline and erythromycin among 165 strains of MRSA was 98.2%, 96.3% and 93.9%, respectively. The sensitivity to trimethoprim/sulfamethoxazole and chloramphenicol were 95.8% and 98.8%, respectively. Five different PFGE patterns (A-E) were found among 65 MRSA strains at ICU and RCU wards. Most of MRSA in two wards were A pulsotype (56 strains). A pulsotype included A1 subtype (55 strains) and A2 subtype (1 strain). Conclusion Hospital acquired MRSA is multi-resistant to antibiotics. A1 subtype MRSA outbreak occured at ICU and RCU wards in 2002.