我国社区儿童皮肤感染金黄色葡萄球菌的耐药研究

摘要

为分析我国社区儿童皮肤感染来源的金黄色葡萄球菌流行特点及耐药现状,明确社区获得性耐甲氧西林金黄色葡萄球菌(CA-MRSA)中mecA基因携带情况及葡萄球菌盒式染色体mec(SCCmec)基因分型情况,并为临床选择合理而有效的治疗方案提供依据.本文对全国13家儿童医院1 416例皮肤感染患儿的皮损分泌物进行细菌培养,应用琼脂稀释法检测16种抗生素对培养的金黄色葡萄球菌最小抑菌浓度,应用聚合酶链式反应对CA-MRSA进行mecA基因检测及葡萄球菌盒式染色体mec( SCCmec)基因分型.从1416例患儿皮损中培养出金黄色葡萄球菌1043株,对16种抗生素的药敏试验结果显示,耐药率前3位依次为红霉素97.3％、青霉素96.7％、克林霉素89.0％,其次为四环素42.2％、氯霉素15.0％、庆大霉素9.8％、环丙沙星6.6％、复方新诺明4.6％、苯唑西林3.4％、头孢呋辛3.1％、利福平2.4％、头孢曲松1.7％、头孢唑啉1.6％、夫西地酸1.3％、莫匹罗星0.8％.CA-MRSA分离率为3.4％.各地区均未发现万古霉素耐药或中介耐药菌株.35株CA-MRSA均携带mecA基因,SCCmec基因分型结果为Ⅳ型14株(40％)、Ⅴ型19株(54.3％)、未定型2株(5.7％).本研究提示,治疗我国社区儿童皮肤金黄色葡萄球菌感染性疾病,全身应用建议首选耐青霉素酶的半合成青霉素和第1、2代头孢菌素,其他可选择的有夫西地酸、复方新诺明、利福平、万古霉素；外用治疗选择莫匹罗星,具有较好的抗菌活性.我国儿童CA-MRSA中mecA携带率为100％,SCCmecⅣ和Ⅴ型为主要类型.%1 043 Staphylococcus aureus (S. Aureus) strains isolated from 1 416 skin lesions collected from children visiting the clinic for the first time with infectious skin diseases at thirteen children's hospitals in China were subjected to a drug susceptibility test by agar dilution method. The mecA gene and the genotypes of Staphylococcal cassette chromosome mec (SCCmec) were identified by polymerase chain reaction (PCR). The results demonstrated that the drug resistance rates were 97.3% of the isolated strains to erythromycin, 96.7% to penicillin, 89% to clindamycin, 42.2% to tetracycline, 15.0% to chloramphenicol, 9.8% to gentamicin, 6.6% to ciprofloxacin, 4.6% to trimethoprim/sulfamethoxazole, 3.4% to oxacillin, 3.1% to cefuroxime, 2.4% to rifampin, 1.7% to ceftriaxone, 1.6% to cefazolin, 1.3% to fusidic acid and 0.8% to mupirocin. None of the isolated S. Aureus strains were resistant to vancomycin. The prevalence of community-acquired methicillin-resistant S. Aureus (CA-MRSA) was 3. 4%, and all the 35 strains were mecA -positive. SCCmec IV and V were identified in 14 and 19 isolates respectively. Two isolates were non-typable. The results suggest that effective antibiotic agents for children with infectious skin diseases are oxacillin, cephalosporin, fusidic acid, trimethoprim/sulfamethoxazole, rifampin, and vancomycin. Mupirocin is the selection for topical application. The mecA gene is detected in 100% of 35 CA-MRSA strains from children with infectious skin diseases in China. SCCmec IV and SCCmec V are the major genotypes.