甲氧西林耐药凝固酶阴性葡萄球菌手术部位感染的实验室检测与分析

Detection of methicillin-resistant coagulase-negative staphylococci in surgicalsite infection and analysis of its nosocomial infection

目的检测MRCNS在SSI的分布和耐药情况;对SSI分离的MRCNS感染因素进行分析。方法PCR检测mecA基因,微量肉汤稀释法检测抗菌药物对MRCNS的最小抑菌浓度(MIC)。万古霉素耐药确证试验筛选万古霉素耐药MRCNS;Etest法检测万古霉素和替考拉宁对确证试验阳性株及其子代菌株的MIC,多重PCR检测其van基因。结果40株SSI分离的CNS菌中mecA基因阳性率为85%;耐药结果显示MRCNS中表皮葡萄球菌和溶血葡萄球菌对环丙沙星、红霉素、左氧氟沙星、诺氟沙星、复方新诺明有较高的耐药率(>49%);34株MRCNS菌中检测到1株溶血葡萄球菌为异质性万古霉素耐药株,多重PCR方法未检出van基因。结论SSI分离的MRCNS发生率较高,异质性万古霉素耐药株的检出应引起临床医师重视;采取有效的措施以及临床实验室加强对MRCNS医院感染进行监测对SSI防控是非常重要的。

Objective To investigate and analyse the prevalence of methicillin-resistant coagulase-negative staphylococci（ MRCNS） and its vaneomycin resistance from SSI in the hospital.Methods mecA were detected with PCR in MRCNS from SSI.The MIC of MRCNS to antibiotics were determined with broth dilution. Method. MRCNS with reduced susceptibihties to vancomycin was detected with vancomycin agar screen test and van gene was detected with mulitplex PCR. Results 85 % of mecA was detected in 40 CNS. S. epidermidis and S. haemolyticus were of high rote of resistance to ciprofloxacin,erythromyein, levofloxacin, norfloxacin and Trimethoprim/Sttlfamethoxazole. One S. haemolyticus with hetero-resistance to vancomycin （hetero-VRS） were screened in 34 MRCNS but without van gene detected. Conclusion s It is of great necessity for the chnical physicians to pay attention to the resistance of MRC- NS and for chnical laboratory to detect MRCNS to prevent SSI caused by MRCNS.