上海地区散发布氏杆菌感染的细菌学及分子鉴定

Bacteriological and molecular identification of a sporadic case of Brucella infection in Shanghai

目的本研究对我院的1例散发布氏杆菌病患者进行细菌学及分子生物学的分析,并在国内首次尝试了用数目可变串联重复单元(VNTR)分子指纹分析法对其进行了基因分型并和国际流行株进行了分子流行病学比较分析。方法对临床疑似布氏杆菌病病例作血液细菌培养与生化鉴定,进一步作布氏杆菌特异性基因片段的序列分析鉴定以及利用布氏杆菌基因组中的8个位点构建VNTR指纹图谱,参照国际布氏杆菌VNTR数据库,构建布氏杆菌基因系统树。结果用细菌学方法确定散发疑似布氏杆菌病病例体内分离到的为布氏杆菌,通过基因序列分析进一步得到证实,但不能鉴定到生物种和生物型。对分离株作VNTR指纹分析提示该散发布氏杆菌病为猪2型布氏杆菌感染所致。结论通过传统细菌培养方法与布氏杆菌VNTR指纹分析可用于我国布氏杆菌病分子流行病学的系统调查。

Objective To identify a sporadic case of brucellosis found in Shanghai by bacteriological and molecular biological methods. Methods Blood culture combined with automatic biochemical identification system was used to isolate the Brucella strain from a patient suspected of brucellosis and a Brucella＇s specific secretary gene was amplified from the strain and analyzed by sequencing. We firstly multiple locl VNTR （Variable Number of Tandem Repeats） was used to analyze the Brucella genotype, by which Brucella dendrogram tree was established based on VNTR fingerprints according to the international published VNTR genotypes data. Results The isolated strain from this sporadic case was identified by bacteriological and molecular biological method as a kind of Brucella species. Although biochemical analysis and special gene sequencing could not identify the biovar of Brucella species, VNTR dendrogram of clustered VNTR genotypes indicated the case of brucellosis belonged to Brncella suis hiovar 2.Conclusion Conventional bacterial cultures with biochemical and Brncella VNTR analysis can be used to identify the infection of Brucella and it is important investigate the molecular epidemiological profile of strains isolated in our country.