2017年山西省婴幼儿流行性脑脊髓膜炎病例病原学分析

目的分析2017年山西省由B群脑膜炎奈瑟菌引起的3例婴幼儿流行性脑脊髓膜炎（流脑）病例病原学特征。方法收集3例婴幼儿流脑病例的临床流行病学资料，采集病例脑脊液和血液标本进行脑膜炎奈瑟菌培养、分离、鉴定和血清分群，采用多位点序列分型（MLST）方法进行分子分型，药敏E-test试纸条法检测抗生素敏感性。结果3例B群流脑病例发病月龄分别为12 d、5月龄和8月龄，符合化脓性脑膜炎症状，脑脊液标本均分离培养出3株B群脑膜炎奈瑟菌。 MLST序列分型分析显示，2株菌为ST-5664（CC4821），1株为ST-5662。 3株B群菌株均对环丙沙星、左氧氟沙星和复方新诺明等药物耐药。结论山西省首次从病例标本中分离到B群脑膜炎奈瑟菌，3例B群流脑病例均为婴幼儿发病，且主要基因型属于CC4821。

Etiology of meningococcal meningitis cases in infants in Shanxi, 2017

ObjectiveTo analyze the etiologic characteristics of three meningococcal meningitis cases in infants in Shanxi province in 2017.MethodsEpidemiological data and clinical samples of suspected meningococcal meningitis cases were collected. Cerebrospinal fluid and blood specimens were used for the culture, isolation, identification of Neisseria meningitidis. Serogroup identification of N. meningitidis isolates were confirmed by slide agglutination test with serogroup B antiserum. Multi locus sequence typing (MLST) was used for molecular typing and E-test method was used for antimicrobial resistance test.ResultsThree meningococcal meningitis cases were aged 12 d, 5 months and 8 months, respectively, showing symptoms of purulent meningitis. Three N. meningitidis B strains were isolated, in which two belonged to ST-5664 (Clonal Complex 4821, CC4821) and one belonged to ST-5662 indicated by MLST. All the serogroup B isolates were resistant to ciprofloxacin, levofloxacin and sulfonamides.ConclusionThree meningococcal meningitis cases caused by N. meningitidis B occurred in Shanxi in 2017, the cases were all infants. It was the first time to isolate N. meningitidis B from case specimens in Shanxi, the major sequence type of the strains belonged to CC4821.