致感染性心内膜炎长奈瑟菌的鉴定和临床分析

Identification and clinical significance of Neisseria elongata isolated from endocarditis

摘要:

目的：鉴定从心内膜炎患者血液中分离出病原菌的生物学性状并鉴定至亚种，并初步探索其引起心内膜炎的机制。方法：按常规鉴定方法进行细菌表型特征的鉴定，16 S rRNA分子生物学方法鉴定，微量生化管分型，体外建立细菌生物膜。结果：常规细菌学与 16 S rRNA分子生物学方法鉴定为长奈瑟菌，微量生化管分型为硝酸盐还原亚种，此菌在体外能形成成熟的生物膜。结论：国内首次发现长奈瑟菌引起的心内膜炎，并且此菌易与其它细菌相混淆。临床微生物工作者应加强对长奈瑟菌引起感染性心内膜炎的认识，并提高对该菌鉴定的准确性。

Abstract:

Objective：To characterize the biological properties of a pathogenic bacteria separated from blood sample from a patient with endocarditis，and then to investigate the pathogenesis preliminarily. Methods：Isolates were initially identified by standard bio－chemical tests including micro biochemical tubes. The bacterial 16 S ribosomal RNA gene（16 S rRNA） was sequenced for molecular biological identification. Biofilms of the isolates were formed in vitro by standard methods. Results：The phenotypic and genotypic re－sults of the isolate were corresponded well with those of Neisseria elongata spp. nitroreducens. In vitro model exhibited the ability of isolates to develop mature biofilms. Conclusion：The reported first case of endocarditis due to Neisseria elongata subsp. nitroreducens in China may attract the attention of clinical microbiologist in identifying this organism.