深圳地区致泻性大肠埃希菌多位点可变数目串联重复序列分析分型方法的研究

目的通过比较多位点可变数目串联重复序列分析（MLVA）和脉冲场凝胶电泳（PFGE）分型方法，探索更优的致泻性大肠埃希菌（DEC）的快速溯源方法。方法本研究采用筛选的可变数目串联重复序列（VNTR）位点，对DEC菌株进行MLVA分型，并将该方法与金标准PFGE进行比较评估。结果PFGE分型方法将58株DEC分为43种带型，其中3种带型成簇，多样性指数（DI）值为0.965。 MLVA分型方法将58株菌分为42种带型，4种型别成簇，DI值为0.955。 此外，2种方法对2起暴发菌株的分型结果一致。结论MLVA方法与PFGE方法对深圳地区的58株DEC菌株的分型能力差异无统计学意义，但MLVA具有快速、简便、通量高的特点，使得MLVA优于PFGE分型方法，在疾病监测、疾病暴发调查中将会发挥重要的应用价值。

Evaluation of multiple locus variable-number tandem repeat analysis for subtyping of diarrheagenic Escherichia coli in Shenzhen

ObjectiveTo explore a better subtyping method for diarrheagenic Escherichia coli (DEC) through the comparison of multiple locus variable-number tandem repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE).MethodsIn this study, variable-number tandem-repeat (VNTR) loci were screened for the use in MLVA for subtyping of DEC, the results were then compared with those of gold standard method-PFGE.ResultsAmong 58 DEC isolates, 43 PFGE patterns from three clusters (DI＝0.965) and 42 MLVA subtypes from four clusters (DI＝0.955) were obtained. The clustering of two outbreak strains showed highly consistent between the two methods.ConclusionAlthough there was no significant difference in discriminatory power betwee MLVA and PFGE, MLVA is a rapid, simple and high-throughput subtyping method, which are superior to PFGE and has great application value in disease surveillance and disease outbreak investigation.