耐红霉素葡萄球菌对克林霉素诱导型耐药的检测

Detection for inducible clindamycin resistance in erythromycin resistant isolates of Staphylococcus

目的了解本院临床分离的葡萄球菌对克林霉素诱导型耐药的发生率，帮助临床医师正确选择药物。方法采用K-B纸片琼脂扩散法检测葡萄球菌对红霉素和克林霉素的耐药性，按照CLSI／NCCLS推荐的D-试验方法检测克林霉素诱导型耐药。结果133株受试葡萄球菌对红霉素和克林霉素耐药菌株数分别为66株（49．6％）和43株（33．3％），66株耐红霉素葡萄球菌中有20株（其中金黄色葡萄球菌10株、表皮葡萄球菌9株、腐生葡萄球菌1株）为克林霉素诱导型耐药株，占红霉素耐药株的30．3％。在红霉素耐药金黄色葡萄球菌和凝固酶阴性葡萄球菌中，克林霉素诱导型耐药的检出率分别达38．5％和25．0％。对红霉素和克林霉素同时敏感或克林霉素耐药株中，未检到克林霉素诱导型耐药株。结论对红霉素耐药而克林霉素敏感的葡萄球菌应进行D-试验，报道克林霉素诱导耐药性结果，以便临床正确选择药物。

Objective To investigate the probability of induction of clindmycin resistance in isolates of Staphylococcus from clinical lab and to help clinical physicians to select appropriate therapy decision. Methods K-B disk diffusion method was used to test erythromycin or clindamycin resistance in isolates of Staphylococcus, D-test recommended by CLSI/NCCLS was used to examine the inducible resistance of erythromycin to clindamycin. Results Erythromycin-resistant isolates and clindamycinresistant isolates accounted for 66 strain （49.6%） and 43 strain （33. 3%） in 133 tested isolates of Staphylococcus respectively. There were 20 inducible clindamycin-resistant isolates （including 10 isolates of S. aureus, 9 isolates of S. epidermidis and 1 isolate of S. saprophyticus. ） whose rate was 30.3% among the 66 erythromycin-resistant isolates. The rate of inducible resistance to clindamycin was 38.5 %0 and 25.0 % in erythromycin-resistant isolates of S. aureus and coagulase-negative Staphylococcus respectively. There was no induction of clindamycin resistance in isolates which possessed both erythromycin and clindamycin sensitive or clindamycin resistant. Conclusion Erythromycin-resistant and clindamycin-sensitive isolates should be checked by D-test in clinical lab so as to offer physicians correct antimicrobial agents information.