儿童呼吸道流感嗜血杆菌分离株耐药性与β-内酰胺酶基因研究  

Antimicrobial resistance and beta-lactamase gene of Haemophilus influenzae isolates from respiratory tracts in children

作　　者：谢成彬[1] 王频佳[2] 吴雨露[1] 颜源[1] 易娟[1] 苏喆[1] 

机构地区：[1]四川省妇幼保健院检验科,四川成都610045 [2]成都医学院检验医学院,四川成都610083

出　　处：《中国微生态学杂志》2013年第5期561-565,共5页Chinese Journal of Microecology

基　　金：四川省卫生厅科研课题(120493)

摘　　要：目的调查儿童呼吸道流感嗜血杆菌分离株的耐药性和产β-内酰胺酶情况,研究分离株β-内酰胺酶基因的特征。方法 2011年1月到2012年6月,从儿童呼吸道分离流感嗜血杆菌,用微量肉汤稀释法测定常用抗生素最低抑菌浓度;用Nitrocefin纸片法检测β-内酰胺酶;用PCR扩增结合限制性内切酶酶切分析对分离株β-内酰胺酶基因进行分型;比较TEM+菌株和ROB-1+菌株、TEM-1+菌株和TEM-2+菌株对常用抗生素的耐药性。结果 537株流感嗜血杆菌的β-内酰胺酶产酶率为52.3%(281/537);产酶株对氨苄西林、头孢克洛、头孢呋辛的MIC50、MIC90和耐药率明显高于非产酶株(P<0.05);产酶株TEM基因阳性率为91.8%(258/281),其中90.3%为TEM-1型(233/258),7.4%为TEM-2型(19/258),ROB-1基因阳性率为8.2%(23/281);ROB-1+菌株对氨苄西林和阿莫西林/克拉维酸的MIC50和MIC90高于TEM+菌株,但头孢菌素类的MIC50和MIC90低于TEM+菌株;除头孢呋辛外,TEM-1+菌株和TEM-2+菌株对β-内酰胺类的MIC50和MIC90差异无统计学意义。结论成都地区儿童呼吸道流感嗜血杆菌分离株β-内酰胺酶产酶率较高,产酶株主要携带TEM-1基因,对氨苄西林、头孢克洛和头孢呋辛等β-内酰胺类的影响明显。Objective To investigate antimicrobial resistance and beta-lactamase production of Haemophilus influenzae isolates from respiratory tracts in children and the characteristics of beta-lactamase gene.Methods From January 2011 to June 2012,Haemophilus influenzae were isolated from respiratory tracts in children.Minimum inhibitory concentrations（MICs） of commonly-used antibiotics were determined by micro broth dilution assay,and beta-lactamase production was detected by Nitrocefin disk test.PCR combining restriction endonuclease analysis was employed to do the beta-lactamase genotyping.Antimicrobial resistance was compared between TEM＋ isolates and ROB-1＋ isolates as well as between TEM-1＋ isolates and TEM-2＋ isolates.Results 52.3% of the isolates were beta-lactamase positive（281/537）,the MIC values（MIC50/MIC90） and resistant rates（R%） of which were higher than those of non beta-lactamase producing isolates against ampicillin,cefaclor and cefuroxime.91.8% of the isolates were TEM gene positive（258/281）,consisting of 93.0% of TEM-1＋ isolates（233/258）,7.4% of TEM-2＋ isolates（19/258）,and 8.2% of ROB-1＋ isolates（23/281）.The MIC50 and MIC90 values of ampicillin and amoxicillin/clavulanate against ROB-1＋ isolates were higher than those against TEM＋ isolates,while those of cephalosporins against ROB-1＋ isolates were lower than those against TEM＋ isolates.No difference was observed in MIC values between TEM-1＋ isolates and TEM-2＋ isolates except cefuroxime.Conclusion There is high prevalence of beta-lactamase producing Haemophilus influenzae isolates from respiratory tracts in Chengdu children;the dominant genotype of beta-lactamase producing isolates is TEM-1,which has obvious influences on some beta lactams such as ampicillin,cefaclor and cefuroxime.

关 键 词：流感嗜血杆菌 耐药性 Β-内酰胺酶 基因 

分 类 号：R378.41[医药卫生—病原生物学]