葡萄球菌属对抗菌药物的耐药性分析

目的了解葡萄球菌属临床分离株的耐药性及对大环内酯类、林可霉素类及链阳霉素类（MLS）的耐药表型。方法用Kirby-Bauer法测定葡萄球菌属对14种抗菌药的敏感性，进行D试验测定MLS耐药表型。结果在230株葡萄球菌属中，耐甲氧西林金葡菌（MRSA）和耐甲氧西林凝固酶阴性葡萄球菌（MRSCN）分别为9．9％和79．8％。对青霉素都呈现高度耐药。未发现万古霉素及替考拉宁耐药菌株，126株葡萄球菌属对红霉素耐药，54．8％（23／42）株金葡菌为结构型耐药；在凝固酶阴性葡萄球菌中（CNS），44．0％（37／84）为结构型耐药，41．7％（35／84）为外排型耐药。对红霉素耐药但对克林霉素敏感的葡萄球菌中，17株为诱导型克林霉素耐药。结论应加强对葡萄球菌的耐药性监测，临床微生物实验室应进行D试验。指导临床合理使用抗生素。

The antimicrobial resistance of Staphylococcus isolates

Objective To investigate the resistance and MLSB resistant phenotypes of Staphylococcus isolated from children infections. Methods Kirby-Bauer method was used to test the resistance of Staphylococci to selected antimicrobial agents. Phenotypes were determined using double disk test with erythromycin and clindamycin disks. Results About 9. 9% of S. aureus isolates were identified as MRSA and 79. 8% of the coagulase-negative Sta phylococcus isolates were identified as methicillin-resist-ant (MRCNS). All the Sta phylococcus strains were highly susceptible to vancomycin and teicoplanin, but highly resistant to penicillin. Of the 230 strains, 126 were erythromycin-resistant. Constitutive resistance to erythromycin was found in 23/42 (54. 8%) strains of S. aureus and 37/84 (44. 0%) strains of CNS. Active efflux mechanism was characterized in 35/84 (41. 7%) strains of CNS. Of the isolates resistant to erythromycin but susceptible to clindamycin. 17 showed inducible resistance to clindamycin. Conclusions The Sta phylococcus isolates must be screened for the potential trend of resistance. D-test should be conducted in clinical microbiology laboratory for guiding rational antimicrobial therapy.