细菌培养、血清学与分子流行病学方法对百日咳诊断价值的评价

Evaluations of bacterial culture and serological assay plus PFGE typing for diagnosis of pertussis.

目的 应用细菌培养、血清学及分子流行病学方法对百日咳诊断进行评价。方法 对 2 0 0 0年 6月至 2 0 0 1年 5月北京儿童医院的 111例受试对象按取标本时咳嗽时间分为 2组 :>2周组 (6 9例 )、<2周组 (42例 )。应用碳琼脂培养基培养百日咳杆菌 ,应用ELISA方法测定百日咳抗体 ,包括抗毒素IgG(PT IgG)与抗丝状血凝素IgG(FHA IgG) ,应用脉冲场凝胶电泳 (PFGE)核型对百日咳杆菌进行流行病学研究。结果 所有 111份鼻咽拭子中 ,8例百日咳杆菌培养阳性 ,阳性率为 7 2 %。测定 111例血清标本的PT IgG及FHA IgG ,分别有2 2 5 % (2 5 / 111)及 10 8% (12 / 111)呈阳性结果 ,总血清阳性率为 2 5 2 % (2 8/ 111)。 10株百日咳杆菌由XbaI与SpeI限制性内切酶消化后在 4 8～ 6 30kb之间分别产生 9～ 11个DNA片段 ,共得 7个PFGE核型。结论 儿童百日咳是导致长期咳嗽的原因之一。鼻咽拭子特殊培养与血清学检查相结合有助于诊断。百日咳杆菌PFGE分型可以鉴别不同地区不同时间的流行菌株 ,并在分子水平上论证了年长儿和成人百日咳患者是婴儿的主要传染源。

Objective To evaluate bacterial culture and serological assay plus PFGE typing for diagnosis of pertussis.Methods A total of 111 patients were divided into two groups according to the cough time at sampling:69 cases longer than two weeks,and 42 shorter than two weeks.Nasopharyngeal swabs were taken from all of 111 patients for bacterial culture and same amount of sera for measurement of pertussis toxin (PT) IgG and filamentous hemaglutinin(FHA) IgG by ELISA assay.PFGE typing were detected by XbaI and SpeI digestion.Results There were 8 (7 2%) cases which had culture positive of B.pertussis among 111 swabs.Among 111 sera,25(22 5%) and 12(10 8%) sera were PT IgG and FHA IgG positive,respectively; 25 2% (28/111) patients were PT and/or FHA antibodies positive.XbaI and SpeI digestion of the chromosome DNA of 10 clinical isolates resulted in 7 PFGE types in 9 to 11 DNA fragments.Conclusion Pertussis is a common respiratory infectious disease,especially in patients with long cough time.The results of both culture and serology are most informative for diagnosis of B.pertussis.The transmission of the B.pertussis from adults and older children to infants was genetically confirmed by PFGE.