Queensland Paediatric Infectious Diseases Laboratory, Department of Infectious Diseases, Royal Children's Hospital, Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, QLD, Australia.
J Clin Microbiol. 2011 Jan;49(1):263-8. doi: 10.1128/JCM.01421-10. Epub 2010 Nov 17.
Monitoring the emergence and transmission of Pseudomonas aeruginosa strains among cystic fibrosis (CF) patients is important for infection control in CF centers internationally. A recently developed multilocus sequence typing (MLST) scheme is used for epidemiologic analyses of P. aeruginosa outbreaks; however, little is known about its suitability for isolates from CF patients compared with that of pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR). As part of a prevalence study of P. aeruginosa strains in Australian CF clinics, we compared the discriminatory power and concordance of ERIC-PCR, PFGE, and MLST among 93 CF sputum and 11 control P. aeruginosa isolates. PFGE and MLST analyses were also performed on 30 paired isolates collected 85 to 354 days apart from 30 patients attending two CF centers separated by 3,600 kilometers in order to detect within-host evolution. Each of the three methods displayed high levels of concordance and discrimination; however, overall lower discrimination was seen with ERIC-PCR than with MLST and PFGE. Analysis of the 50 ERIC-PCR types yielded 54 PFGE types, which were related by ≤ 6 band differences, and 59 sequence types, which were classified into 7 BURST groups and 42 singletons. MLST also proved useful for detecting novel and known strains and for inferring relatedness among unique PFGE types. However, 47% of the paired isolates produced PFGE patterns that within 1 year differed by one to five bands, whereas with MLST all paired isolates remained identical. MLST thus represents a categorical analysis tool with resolving power similar to that of PFGE for typing P. aeruginosa. Its focus on highly conserved housekeeping genes is particularly suited for long-term clinical monitoring and detecting novel strains.
监测铜绿假单胞菌（Pseudomonas aeruginosa）菌株在囊性纤维化（cystic fibrosis，CF）患者中的出现和传播，对于国际 CF 中心的感染控制非常重要。最近开发的多位点序列分型（multilocus sequence typing，MLST）方案用于铜绿假单胞菌暴发的流行病学分析；然而，与脉冲场凝胶电泳（pulsed-field gel electrophoresis，PFGE）和肠细菌重复基因间一致性聚合酶链反应（enterobacterial repetitive intergenic consensus-PCR，ERIC-PCR）相比，其用于 CF 患者分离株的适宜性知之甚少。作为澳大利亚 CF 诊所中铜绿假单胞菌菌株流行率研究的一部分，我们比较了 93 例 CF 痰液和 11 例对照铜绿假单胞菌分离株中 ERIC-PCR、PFGE 和 MLST 的分辨力和一致性。还对来自两个相隔 3600 公里的 CF 中心的 30 名患者的 30 对分离株进行了 PFGE 和 MLST 分析，以检测宿主内进化。三种方法均显示出高度的一致性和分辨力；然而，与 MLST 和 PFGE 相比，ERIC-PCR 的总体分辨力较低。对 50 种 ERIC-PCR 型的分析产生了 54 种 PFGE 型，它们之间的差异≤6 条带，59 种序列型分为 7 个 BURST 组和 42 个单倍型。MLST 也可用于检测新型和已知菌株，并推断独特的 PFGE 型之间的相关性。然而，47%的配对分离株在 1 年内 PFGE 图谱差异为 1 至 5 条带，而 MLST 中所有配对分离株均相同。因此，MLST 是一种分类分析工具，其分辨率与 PFGE 相似，适用于铜绿假单胞菌分型。它专注于高度保守的管家基因，特别适合长期临床监测和检测新型菌株。
