唐山市首例B群流脑病例病原学鉴定及分子分型

Etiological and molecular subtypes analysis of the first serogroup B epidemic cerebrospinal meningitis case in Tangshan

目的对河北省唐山市首例B群流行性脑脊髓膜炎(流脑)病例进行病原学及分子分型分析。方法采集患儿血液标本,分离菌株,进行生化、血清鉴定,荧光聚合酶链反应(Polymerase Chain Reaction,PCR)检测,多位点序列分型(multilocus sequence typing,MLST)分析,外膜蛋白编码基因porA基因分型及药物敏感性试验。结果生化、血清学鉴定以及PCR检测结果均显示该菌株为B群Nm菌株,该病例证实为B群脑膜炎奈瑟菌引起的脑膜炎病例,MLST结果分析其属于ST-4821高致病克隆群,porA分型为P1.20-3,23-7,该菌株对磺胺甲基异噁唑、萘啶酸耐药,对米诺环素、青霉素等敏感。结论该病例为河北省唐山市首例B群流脑病例,且为具有高致病性的ST-4821型脑膜炎奈瑟菌,该高致病性克隆群的B群Nm已在本省多地出现散发病例,提示应加强该类病原菌的监测。

Objective To analyze the etiological characteristic and molecular subtypes of the first serogroup B Epidemic cere- brospinal meningitis case in Tangshan city of Hebei province. Methods The blood of the sick infant was collected. The strain was isolated. The sample was identified by biochemistry test and fluorescence polymerase chain reaction（PCR） for target gene. The strain was analyzed by muhilocus sequence typing （MLST） and porA subtyping. The drug susceptibility test was performed. Results The result of biochemistry test, serological test and real - time PCR showed that this strain was serogroup B Neisseria meningitidis. The case was confirmed to be the Neisseria meningitidis serogroup B infection. The result of MLST showed that the strain belonged to highly pathogenic ST -4821 clonal complex. The porA type was P1.20 -3 ,pl. 23 -7. The strain was resist- ant to sulfamethoxazole, nalidixic acid and insensitive to minocycline, penicillin and so on. Conclusion This was the first case of Neisseria meningitidis serogroup B infection in Tangshan city of Hebei province and belonged to highly pathogenic ST- 4821 clonal complex. The Neisseria meningitidis serogroup B of highly pathogenic clonal complex had already existed in Hebei prov- ince. Surveillance on these Neisseria meningitidis serogroup B should be strengthened.