儿科分离金黄色葡萄球菌耐药性和耐甲氧西林株的流行病学研究

摘要

目的 了解儿童感染金黄色葡萄球菌的耐药性和耐甲氧西林金黄色葡萄球菌(MRSA)的基因型及分布,为临床治疗提供依据和确定MRSA流行情况.方法 采用ATB分析系统对菌株进行药敏试验,头孢硝基噻吩显色法检测β-内酰胺酶,随机扩增多态DNA(RAPD)方法进行MRSA同源性分析.结果 348株金黄色葡萄球菌中,334株产β-内酰胺酶,对β-内酰胺类抗菌药物的耐药率为6.03%～100.00%.耐药率较高的有四环素(65.23%)、大环内酯类(64.66%)、复方新诺明(48.28%)和克林霉素(43.97%),较低的有呋喃妥因(3.74%)、利福平(4.02%)、左氧氟沙星(8.91%)和环丙沙星(16.38%).未发现对万古霉素、替考拉林和利奈唑胺耐药.MRSA的检出率为9.77%,MRSA对17种抗菌药物的耐药率高于甲氧西林敏感金黄色葡萄球菌(MSSA).经RAPD分型,34株MRSA分为6型,以Ⅰ型为主(64.71%),主要分布于儿科PICU.结论 本地区儿童感染金黄色葡萄球菌有不同耐药谱,应加强儿童感染金黄色葡萄球菌的耐药性监测和掌握MRSA流行情况,对防止耐药性进一步蔓延和MRSA感染暴发有重要意义.%Objective To investigate the drug resistance of Staphylococcus aureus ( SA ) infection in children and genotype distribution of Methicillin resistant staphylococcus aureus ( MRSA ), so as to provide a reference for clinical use of antibiotics and determine the prevalence of MRSA. Methods All strains were performed antimicrobial susceptibility testing by ATB analysis system, β -lactamase was detected by the nitrocefin assay, and MRSA was genotyped by random amplified polymorphic DNA ( RAPD ) . Results Among 348 strains of SA, β -lactamase was detected in 334 stains. The drug resistant rate of β -lactamase antibiotics was 6. 03％ ～ 100. 00％. The drug resistant rates of SA to tetracycline ( 65. 23％ ). macrolides ( 64. 66％ ). cotrimoxazole ( 48. 28 7％ ) and clindamycin ( 43. 97％ ) were higher, but those to nitrofurantoin ( 3. 74％), rifampicin ( 4. 02％　 ), levofloxacin ( 8. 91％ ) and ciprofloxacin ( 16. 38％ ) were lower. The SA isolates resistant to Vancomycin, Teicoplanin and Linezolid were not found. The detection rate of MRSA was 9. 77％ . MRSA was more resistant t0 17 kinds of antibiotics than Methicilin Susceptible Staphylococcus aureu ( MSSA ). Genotyped hy RAPD , 34 MRSA strains were divided into 6 types, with a dominant type of RAPD Ⅰ ( 64. 71％ ), and they were mainly distributed in pediatric intensive care unit ( ICU ).Conclusion There were different resistance patterns of SA in the; local area of Nanning. In order to prevent the spread of drug resistance and the outbreak of MRSA infection, it was essential to strengthen monitor of drug resistance and investigate the prevalence of MRS.