Surdeanu Maria, Ciudin Lucia, Pencu Elena, Straut Monica
Molecular Epidemiology Laboratory, Cantacuzino Institute, Bucharest, Romania.
Eur J Epidemiol. 2003;18(7):703-10. doi: 10.1023/a:1024831609901.
In this study, 97 epidemiologically unrelated Shigella flexneri strains isolated during 1994 (69 isolates) and 1997 (28 isolates) were characterised by ribotyping, enterobacterial repetitive intergenic consensus sequence-based PCR typing, and pulsed-field gel electrophoresis. Number of strains belonging to each of the six serotypes is selected equal to their distribution in Romania. The isolates comprise 24 ribotypes based on combination of two restriction patterns obtained with HindlII and PstI, respectively, 7 enterobacterial repetitive intergenic consensus (ERIC)-PCR types, and 92 XbaI pulsed-field gel electrophoresis (PFGE) patterns grouped in 31 pulsotypes at Dice coefficients of 85% similarity. We find no significant difference in the distribution of isolates collected during the two periods. Macrorestriction analysis by PFGE offers maximal discrimination. There seems to be little genetic variability among circulating S. flexneri strains of serotype 2a, suggesting that even a combination of several molecular techniques, including PFGE, could not easily differentiate an outbreak strain from temporally associated independent isolates.
在本研究中，对1994年（69株分离株）和1997年（28株分离株）期间分离出的97株流行病学上无关的福氏志贺菌菌株进行了核糖体分型、基于肠杆菌重复基因间共有序列的聚合酶链反应分型和脉冲场凝胶电泳分析。每个六种血清型的菌株数量根据其在罗马尼亚的分布情况选择。这些分离株基于分别用HindIII和PstI获得的两种限制性酶切图谱组合，分为24种核糖体分型，7种肠杆菌重复基因间共有序列（ERIC）-PCR型，以及92种XbaI脉冲场凝胶电泳（PFGE）图谱，在相似性为85%的迪氏系数下归为31个脉冲型。我们发现这两个时期收集的分离株分布没有显著差异。PFGE进行的宏观限制性分析具有最大的分辨力。2a血清型的流行福氏志贺菌菌株之间似乎几乎没有遗传变异性，这表明即使包括PFGE在内的几种分子技术联合使用，也很难将暴发菌株与同期相关的独立分离株区分开来。
