广州部分公共场所葡萄球菌污染状况和耐药谱及其分子特征研究

发布时间：2018-02-02 12:19

  本文关键词： 公共场所 葡萄球菌 药敏试验 分子流行病学　出处：《广东药学院》2015年硕士论文　论文类型：学位论文

【摘要】：目的调查广州部分公共场所环境物体表面葡萄球菌污染情况,揭示其耐药谱及分子特征,为预防和控制公共场所葡萄球菌污染提供科学依据。方法采用横断面研究设计,调查地铁、火车站、汽车站和医院候诊大厅葡萄球菌污染状况;应用一系列标准的微生物实验方法进行菌株的分离和鉴定;采用纸片扩散法对所有葡萄球菌进行药物敏感试验;使用PCR技术检测金黄色葡萄球菌中PVL基因和qac基因携带情况,并对金黄色葡萄球菌进行多位点测序分型(multilocus sequencing typing,MLST);应用多重PCR技术对耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)的进行SCC mec分型。结果葡萄球菌污染情况:共采集公共场所物体表面样本1100份。葡萄球菌检出率为59.64%(656/1100):金黄色葡萄球菌污染率为7.55%(83/1100),其中MRSA污染率为1.73%(19/1100);凝固酶阴性葡萄球菌污染率为52.09%(573/1100),其中耐甲氧西林凝固酶阴性葡萄球菌污染率为6.09%(67/1100)。各个场所葡萄球菌污染率由高到低依次为:地铁(75.63%,242/320)医院(66.25%,265/400)火车站(43.89%,79/180)汽车客运站(35.00%,70/200);金黄色葡萄球菌污染率由高到低依次为:地铁(11.25%,36/320)汽车客运站(8.50%,17/200)火车站(6.67%,12/180)医院(4.50%,18/400)。药物敏感试验:葡萄球菌对11种药物均有不同程度耐药,药物按照耐药率由高到低依次为:青霉素(94.05%)红霉素(84.15%)克林霉素(57.62%)利福平(48.78%)甲氧苄啶(42.23%)庆大霉素(31.25%)莫西沙星(21.29%)妥布霉素(14.33%)头孢西丁(12.65%)替考拉宁(3.66%)利奈唑胺(2.44%)。金黄色葡萄球菌对头孢西丁和妥布霉素的耐药率高于凝固酶阴性葡萄球菌,对克林霉素和红霉素的耐药率低于凝固酶阴性葡萄球菌,差异有统计学意义(P0.05),其他药物耐药率在两组间无统计学差异;甲氧西林耐药菌株和甲氧西林敏感菌株对红霉素耐药率无统计学差异,甲氧西林耐药菌株对其他药物的耐药率均高于甲氧西林敏感菌株,差异有统计学意义(P0.05);各采样场所间耐药率存在一定差异。PVL基因和qac基因检测:有2株MRSA(2/19,10.53%)和9株甲氧西林敏感的金黄色葡萄球菌(methicillin-susceptible Staphylococcus aureus,MSSA)(14.06%,9/64)携带PVL基因,两组间PVL基因携带率没有统计学差异(Fisher确切概率法,P=1.000);有9株MRSA(47.37%,9/19)和0株MSSA(0.00%,0/64)携带qac基因,两组间qac基因携带率有统计学差异(Fisher确切概率法,P0.001)。SCCmec分型:在19株MRSA中,SCCmecⅠ型有1株(5.26%),Ⅱ型有3株(15.79%),Ⅲ型有2株(10.53%),Ⅳa型有5株(26.32%)未分型的有8株(42.11%),未检测到Ⅳb型、Ⅳc型、Ⅳd型和Ⅴ型。MLST:金黄色葡萄球菌共检测到27种ST型别,频率由高到低依次为:ST188(26.55%)ST5(17.19%)ST72(15.63%)ST398(12.50%)ST6、ST15和ST1462(6.25%)ST125(4.69%)ST59、ST97和ST2140(3.13%)ST8、ST25、ST30、ST88、ST221、ST338、ST537、ST789、ST808、ST1141、ST1311、ST1507、ST1860、ST2114、ST2605和ST2668(1.56%)。根据ST型别间聚类分析,共形成3个克隆群(CC5,CC59和CC72),4个成对体(D6,D30,D188和D398)和8个单体(ST8,ST15,ST25,ST88,ST97,ST789,ST1141和ST2668)。通过对MRSA菌株进行菌株间树状聚类分析,19株MRSA菌株聚成5个型别,提示可能存在不同公共场所间菌株交叉传播的风险。结论广州公共场所环境物体表面葡萄球菌污染情况严重;这些葡萄球菌对常用抗生素耐药率较高;金黄色葡萄球菌中存在一定数量PVL基因阳性菌株,MRSA菌株中qac基因携带率较高;MRSA菌株出现医院和社区来源并存的现象;ST型别与我国近期流行菌株相符,大部分菌株属于国际流行菌株,MRSA可能存在不同场所间菌株交叉传播的风险。
[Abstract]:Objective to investigate the Guangzhou public environmental surface Staphylococcus contamination, revealing the resistance spectrum and molecular characteristics, and provide scientific basis for the prevention and control of public places of Staphylococcus contamination. Methods the cross-sectional design and investigation of the subway, train station, bus station and hospital waiting hall Staphylococcus contamination; separation and identification of strains microbial experimental method of applying a series of standard; disk diffusion method was used for drug sensitivity test of Staphylococcus aureus; with detection of Staphylococcus aureus using PCR PVL gene and QAC gene, and Staphylococcus aureus were characterized by multilocus sequence typing (multilocus sequencing, typing, MLST); the application of multiplex PCR methicillin resistant Staphylococcus aureus (methicillin-resistant Staphylococcus, aureus, MRSA) of SCC MEC. The results of grape Aureus contamination: public places were collected 1100 samples. The surface of Staphylococcus aureus detection rate was 59.64% (656/1100): Staphylococcus aureus contamination rate was 7.55% (83/1100), in which MRSA pollution rate was 1.73% (19/1100); coagulase negative Staphylococcus contamination rate was 52.09% (573/1100), including methicillin resistant coagulase negative Staphylococcus contamination rate was 6.09% (67/1100) in various places. Staphylococcus infection rate from high to low in turn: the subway (75.63%, 242/320) hospital (66.25%, 265/400) train station (43.89%, 79/180) car passenger transport stations (35%, 70/200); Staphylococcus aureus contamination rate from high to low the subway: (11.25%, 36/320) bus station (8.50%, 17/200) train station (6.67%, 12/180) hospital (4.50%, 18/400). Drug sensitivity test: Staphylococcus to 11 kinds of drugs have different degrees of resistance, according to the drug resistance rate from high to low: penicillin (94. 05% (84.15%)) erythromycin clindamycin (57.62%) rifampin (48.78%) and (42.23%) gentamicin (31.25%) moxifloxacin (21.29%) tobramycin (14.33%) cefoxitin (12.65%) and Ti Koa Laing (3.66%) linezolid (2.44%). Staphylococcus aureus resistant to cefoxitin and tobramycin was higher than that of coagulase negative Staphylococcus resistance to clindamycin and erythromycin was lower than that of coagulase negative staphylococcus, the difference was statistically significant (P0.05), other drug resistance rate showed no significant difference between the two groups; methicillin-resistant strains of methicillin and methicillin sensitive strains had no significant difference on erythromycin resistant strains of methicillin resistant, resistant to other drugs were higher than methicillin sensitive strains, the difference was statistically significant (P0.05); the drug resistance rate among the sampling sites, detecting the presence of certain differences between the.PVL gene and QAC gene: 2 strains of MRSA (2/19 ,10.53%)鍜，

本文编号：1484496