沈阳地区儿科产超广谱β内酰胺酶革兰阴性菌的耐药性与基因型研究【摘要】目的研究沈阳地区儿科产超广谱β内酰胺酶(extendedspectrumβlactamases，ESBLs)革兰阴性菌的耐药性及ESBLs基因型分布，初步探讨其多重耐药性传播的分子机制。方法KB法药敏试验，按照CLSI/NCCLS2005年标准筛选确认ESBLs表型，PCR法进行ESBLs基因型别分析，扩增I类整合子全可变区，分析产ESBLs菌株中整合子的存在情况。结果在分离出的180株革兰阴性菌中，有62株经表型确证试验证实为产ESBLs菌株，检出率%。产ESBLs菌株对各种抗菌药物的耐药率明显高于非产ESBLs菌株。基因分型结果表明，blaTEM基因阳性48株(%)，blaSHV阳性32株(%)，blaCTXM9组阳性31株(50%)，blaCTXM3组阳性12株(%)。62株ESBLs菌株中26株整合子全可变区PCR扩增阳性，阳性率%。结论沈阳地区儿科革兰阴性菌中ESBLs菌株检出率较高，多数菌株同时携带两种或两种以上不同型别的β内酰胺酶，且为多重耐药菌株，整合子机制参与其多重耐药性的形成与传播。【关键词】革兰阴性菌；超广谱β内酰胺酶；耐药；基因型；整合子；沈阳地区；儿科InvestigationofantimicrobialresistanceandgenotypesofextendedspectrumβlactamasesproducingGramnegativebacteriaisolatedfrompediatricsinShenyangABSTRACTObjectiveTostudytheantimicrobialresistanceandgenotypesofextendedspectrumβlactamases(ESBLs)producingGramnegativebacteriaisolatedfrompediatricsinShenyangandpreliminarilyinvestigatethemolecularmechanismsofthrmultipleantibioticresistancedisseminationprocess.MethodsAntibioticssusceptibilitywastestedbyKirbyBauermethod.ESBLsproducingisolatesweredetectedbyphenotypicconfirmatorytestaccordingtoCLSI/NCCLSM100S15(2005).ThegenotypesofESBLswereanalyzedbyPCR,andthecompletevariableregionofclass1integronwereamplifiedinordertoanalyzethepresenceandcharacterizationofclass1integroninESBLs.ResultsAmongatotalof180Gramnegativeisolates,62isolateswereidentifiedasESBLsbyphenotypicconfirmatorytestandtheincidencewas%.TheESBLsproducingisolatesweremoreresistanttomostantimicrobialsthannonESBLsproducers.Theresultsofβlactamasesgenotypingshowedthat48isolatescarriedblaTEM(%)，32isolatescarriedblaSHV(%),31isolatescarriedblaCTXM9(50%)and12isolatescarriedblaCTXM3(%).Class1integronswereidentifiedamong26isolatesandthepositiveratewas%.ConclusionsInShenyangpediatrics,theincidenceofESBLsproducingstrainswashighandmostisolatesweremultipleresistantandproducedmorethanonetypeofβlactamase.Themechanismsofintegrontookpartintheemergenceanddisseminationofthrmultipleresistance.KEYWORDSGramnegativebacteria;Extendedspectrumβ