Antibiotics Resistance of Staphylococcus aureus Isolated from Nosocomial Infection Patients and Detection of Resistance Genes

OBJECTIVE To investigate the antibiotics resistance and the presence of resistant gene of Staphylococcus aureus isolated from nosocomial infection patients in our hospital.METHODS Antibiotic susceptibility tests were conducted by Microscan WalkAway-40,the antibiotics resistant genes of aac(6')/aph(2″),aph(3')-Ⅲ,ant(4',4″),TEM,tetM,macA,erm and qacA/B of 16 MRSA and 24 MSSA strains were detected by PCR.RESULTS The percentage of MRSA in this investigation was 59.4%,the positive rate of β-lactamases of 192 S.aureus strains was 98.9%,resistant rate of S.aureus to β-lactam antibiotics was 52.1-99.0%,and to erythromycin,clindamycin,clarithromycin,ciprofloxacin,norfloxacin,gentamicin and tetracycline was 52.1%,78.1%,85.5%,56.3%,61.1%,55.2%,and 69.8%,respectively,but to nitrofurantoin and sulfamethoxazole/trimethoprim were relatively lower(1.1% and 10.5%) than the others.VISA,h-VISA and VRSA were not measured.To the most of antibiotics,the resistant rate of MRSA was higher than MSSA.The presence of resistant gene of MRSA and MSSA was different.There was more positive percentage of gene in MRSA than in MSSA.CONCLUSIONS Antibiotics resistance of S.aureus isolated from nosocomial infection patients in our hospital is severe.Compared to MSSA,MRSA has higher antibiotic resistant rate and more complicated drug-resistant mechanism.Some measures should be done to reduce the antibiotic resistance of S.aureus.