摘要目的 通过探讨一株罕见菌——霍氏鲍特菌(Bordetella holmesii,B.holmesii)的鉴定及耐药特征,分析其临床意义,提高对该菌的检出及临床诊疗水平.方法 从细菌培养特性、生化特征以及16S rRNA基因序列分析来鉴定一株菌血症分离菌;运用Mega 7.0软件对鲍特菌属全部成员模式菌株与所分离菌16S rRNA基因序列进行同源性比对,并构建系统进化树;E-test法检测该分离菌的药物敏感性;分别添加不同浓度核黄素及其抑制剂光黄素于该菌培养基中,检测其生长活力.结果 引起该免疫功能完善者菌血症的病原菌为B.holmesii,并将菌种上传中国普通微生物菌种保藏管理中心(CGMCC,菌种保藏号:CGMCC 1.13721);同时将该分离菌B.holmesii ABD216S rRNA基因序列上传美国国家生物技术信息中心(NCBI,序列号:KT828544.1);无根树显示B.holmesii与百日咳鲍特菌更具有亲缘性;药物敏感性试验(AST)显示哌拉西林、头孢他啶、头孢吡肟、亚胺培南、美罗培南、环丙沙星、左氧氟沙星、庆大霉素、阿米卡星、红霉素、四环素以及多黏菌素对该菌株的最小抑菌浓度(minimum inhibitory concentration,MIC)较低,而头孢唑啉、头孢呋辛酯、头孢西丁、头孢噻肟、氨曲南及复方新诺明的MIC值较高;核黄素能够促进B.holmesii的生长,光黄素则抑制该菌的生长.结论 B.holmesii分离率极低,鉴定困难,因此临床、微生物学以及流行病学相关资料甚少,为一种罕见的病原菌,有待我们更深入地探讨.

abstractsObjective To analyze the identification, drug resistance and clinical significance of a rare bacterium of Bordetella holmesii ( B. holmesii) to improve its detection and clinical diagnosis and treat-ment. Methods A strain isolated from a bacteremia case was identified by bacterial culture, biochemical tests and 16S rRNA gene sequencing. Mega 7. 0 software was used to conduct a similarity analysis of 16S rRNA gene sequences between the type strains of Bordetella spp. and the isolate, and then a phylogenetic tree was constructed. Antibiotic resistance of the isolate was determined by E-test. Changes in bacterial growth were measured after adding different concentrations of riboflavin or its inhibitor lumiflavin to the cul-ture medium. Results B. holmesii ABD2 was the pathogen causing bacteremia in the immunocompetent pa-tient. It was deposited under the number of CGMCC 1. 13721 in China General Microbiological Culture Col-lection Center (CGMCC), and the 16S rRNA gene sequences were deposited in National Center for Biotech-nology Information ( NCBI) with the accession number of KT828544. 1. Unrooted tree showed that the B. holmesii strain was highly homologous with B. pertussis. Antibiotic susceptibility test showed that the mini-mum inhibitory concentrations ( MIC) of piperacillin, ceftazidime, cefepime, imipenem, meropenem, cipro-floxacin, levofloxacin, gentamicin, amikacin, erythromycin, tetracycline and polymyxin B against the isolate were low, while the MIC values of cefazolin, cefuroxime, cefoxitin, cefotaxime, aztreonam and trime-thoprim-sulfamethoxazole were high. Riboflavin accelerated the growth of B. holmesii ABD2, while its inhibi-tor lumiflavin had an inhibitory effect. Conclusions As B. holmesii is hard to isolate and identify, limited clinical, microbiological and epidemiological data are available. It is an under-recognized pathogen with a considerable amount of information that remains to be studied.