流感嗜血杆菌脉冲电场凝胶电脉法分型研究

Subtyping study of antibiotics-resistant haemophilus influenzae and its b tyPe by pulse field gel electrophoresis

为了解北京儿童医院流感嗜血杆菌 (Hi)抗生素耐药菌株和b型菌株(Hib)的分子流行病学情况 ,采用脉冲电场凝胶电泳(PFGE)方法 ,对1999年和2000年分离的氨苄青霉素、头孢菌素耐药株、b型流感嗜血杆菌菌株和随机选取的非b型抗生素敏感菌株进行分型。结果显示 ,20株Hi菌株 ,得到19种不同PFGE带型。1999年3株氨苄青霉素耐药菌株中有2株仅有一条带的差别 ;4株Hib菌株中 ,2株带型完全相同 ,与另1株有一条带的差别 ;2株头孢菌素耐药株有各自不同带型。2000年所有菌株带型各异。提示1999年从肺炎病人鼻咽部分离的氨苄青霉素耐药及Hib菌株多为流行病学相关菌株 ;2000年从上呼吸道感染儿童鼻咽部分离的氨苄青霉素耐药及Hib菌株无流行病学相关性 ,需要进一步监测方能确定有无耐药及Hib菌株流行。PFGE是对Hi进行流行病学研究的最佳工具之一。

in order to investigate the molecular epidemiology of the antibioTiCs_resistant haemophilus influenzae(hi)strains and its b type(hib)isolated iN our hospital,pulse field gel electrophoresis assay was adopted to carry out a subtyping study for20hi isolates,including7ampicillin_resistant strains,2cephAlosporins_resistant strains,6hib,1hib strain with ampicillin_resistance and4nOn_b type hi with antibiotics_sensitivity randomly chosen,during the years1999aNd2000.as a result,as many as19different pfge bandage patterns could be presentEd in the total of20hi isolates.through the separate analysis of the isolates duRing1999,2of3isolates with ampicillin_resistance were found to have only1differEnt band,2cephalosporins_resistant hi isolates showed wholly different patterns and2of4hib isolates had identical bandage pattern but accompanied with another ONe having only1different band.on the contrary,the pfge bandage patterns showed THe extreme diversity in all hi isolates during2000.therefore,ampicillin_resistaNt and hib isolates identified in children with pneumonia in the year1999were alL found to be epidemiologically related,otherwise,there was no epidemiological relations according to the bandage patterns of pfge assay in2000.thus,the authOrs claim that an effective surveillance programme should be needed to discover WHether any epidemic of dominant antibiotics_resistant hi infection will take plaCe,and pfge assay should be one of the most powerful tools for this purpose in SUch studies.