内蒙古乌兰察布布氏菌分离株种型鉴定及流行病学特征分析

目的 鉴定临床分离布氏菌种型,并分析患者的流行病学特征。方法 以牛种、羊种、猪种标准参考菌株为试验对照,采用经典方法和VITEK2.0进行初步鉴定,用AMOS-PCR进行确证,并分析患者的流行病学特征。结果 经典鉴定115株均为羊种菌,羊3型93株,羊1型22株;115株菌ProA、TyrA、URE和GlyA全部阳性;91株ELLM阳性、14株APPA阳性,提示均为布氏菌,其中羊种菌91株,猪种菌14株。与经典实验的鉴定符合率比较鉴定布氏菌属100%,鉴定布氏菌种为79%(91/115);AMOS-PCR均获得了约731 bp的特异性扩增条带,证实全部为羊种菌。初诊患者84例,构成比为73%;临床表现以疼痛、发热、乏力、多汗居多;88例患者就诊前无用药史,2例有布病治疗史。结论 VITEK2.0是一种高效的布氏菌鉴定方法,但不能替代经典方法;羊种3型菌为该地区的主要流行菌种,再感染可能是慢性患者或有布病治疗史患者分离到布氏菌的主要因素,初诊、未用抗生素且症状典型是分离布氏菌的重要指标。

Species identification and epidemiological characteristics analysis of Brucella in Ulanqab,Inner Mongolia,China

The aim of present study is to identify species/biovar of Brucella clinical isolates and to analyze epidemiological characteristics of brucellosis patients. Standard Brucella strains including B. abortus, B. melitensis, and B. suis were used as positive controls. Automatic microbial identification system vitek 2.0 and classical biotyping methods were used for preliminary identification, and then further examined by AMOS-PCR. Epidemiological features of 115 patients were analyzed. Classical identification showed that 115 strains of Brucella were all B. melitensis, including 93 B. melitensis biovar 3 strains and 22 B. melitensis biovar 1 strains. All these strains exhibited positive results with ProA, TyrA, URE and GIyA, implying that all strains were B. melitensis. While there were 91 strains with ELLM positive reaction and 14 strains with APPA positive reaction, indicating that there might be 91 B. melitensis strains and 14 B. suis strains. Compared with classical methods, the Vitek showed a coincidence rate of 100% and 79% on genus and species identification, respectively. A specific 731 bp amplified products were detected for every strain in AMOS-PCR, confirmed that all tested strains were B. melitensis. There were 84 newly diagnosed patients, covering 73%, with the major clinical symptoms of pain, fever, weakness and sweating. The 88 patients hadn’t taken any medication before diagnosis, while two had a treatment history for brucellosis. Vitlk 2.0 system is an efficient method for Brucella identification, but it can not replace classical identification methods yet. B. melitensis biovar 3 is the major epidemic strains in this region. Brucella isolated from patients with chronic brucellosis or with treatment history for brucellosis might be because of reinfection. Newly diagnosed patients, no antibiotic treatments and obvious symptoms were important index for obtaining Brucella.