Study of inducible resistance of erythromycin to clindamycin in staphyloccus aureus

Objective:To investigate the resistance of Staphylococcus aureus to clindamycin and erythromycin and detect the incidence of the inducible clindamycin resistance.Methods:We used the disk diffusion method(CLSI 2007),to detect the resistance of MRSA and staphylococcus aureus to clindamycin and erythromycin.The double-disk diffusion method(D-test) was employed to detect erythromycin-induced clindamycin resistance.Results:MRSA was 71.7%(297/414) in Staphylococcus aureus,the co-resistance stains to erythromycin and clindamycin was 60.9%(181/297)in MRSA and 52.9%(62/117)in MSSA,resistance to erythromycin and clindamycin-sensitive in MSSA and MRSA,the positive rate of D-test was 62.7% and 64.5%.The positive rate of D-test was 20.3% in Staphylococcus aureus,D-test positive stains was 63.2% in resistance to erythromycin and clindamycin-sensitive strains.Conclusion:D-test should be implemented in clinical microbiological laboratory.To detect the Erythromycininduced resistance to clindamycin in Staphylococcus aureus can guide clinicians to rationally prescribe macrolides and link amide antibiotics to patients.