Establishment and evaluation of the new typing systems for the epidemiological investigation in MRSA (Methicillin Resistant Staphylococcus Aureus) infections

MRSA（耐甲氧西林金黄色葡萄球菌）感染流行病学调查新分型系统的建立和评价

• 批准号: 02671034
• 负责人: MATSUMOTO Hideki
• 金额: $ 1.28万
• 依托单位: School of Medicine, Shinshu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02671034/
• 关键词: MRSA (Methicillin Resistant Staphylococcus Aureus); Pulsed Field Gel Electrophoresis; Plasmid DNA; Biochemical Characteristics; パルスフイ-ルド電気泳動; MRSA型別; MRSA疫学調査

This study has been carried out to know the most useful way to " type " the MRSA strains for the epidemiological servey in the infections caused by the bacterium. Six typing systems of S. aureus have been evaluated for their utility for the each 96 MRSA and 12 MSSA (Methicillin Se-nstitive S. aureus) strains of known origins. Analysis by Pulsed Field Gel Electrophoresis (PFGE) for the genomic DNA cut with a restriction enzyme, SmaI, enabled us to classify the strains into 14 types based on the DNA bands separated by the electrophoresis. Ninty-eight per cent strains were revealed to have a plsmid or plasmids and molecular size of the DNA ranged from about lkb to 40kb. A very interesting finding was that 87% of the MRSA have, in common, a plsmid of 24, 3 kb. This plasmid was rarely detected in MSSA. Results of the biochemical tests, i. e., fermentation of lactose and sucrose, could classify the strains into the four biotypes which seemed to be of limited epidemiological value. In the phage typing, only 10% strains of MRSA were sensitive to one or more typing phage (s) diluted to IRTD. By contrast, 73% strains of MSSA were typable. Typing by coagulase (cell free) neutralization test (antisera from type I to type VIII inclusive were employed) gave a disappointing results for the purpose of epidemiological investigation, as the 98% strains belonged to a same type, type ii. All of the results summarized above led us to conclude as follows ; In the epidemiological investigation of the infections due to MRSA, at least when we are going to clarify the spread of contamination, the most useful way to " type " an isolate is combination of the results presented by analysis, by PFGE, for genomic DNA digested with SmaI, analysis of plasmic DNA, especially those which is larger than 20kb and biotyping based on their ability to ferment lactose and sucrose.

本研究旨在了解MRSA菌株“分型”的最有效方法，以便在细菌引起的感染中进行流行病学调查。S.金黄色葡萄球菌已评估了它们对每96个MRSA和12个MSSA（甲氧西林敏感性S.金黄色葡萄球菌）来源已知的菌株。通过脉冲场凝胶电泳（PFGE）分析用限制性内切酶SmaI切割的基因组DNA，使我们能够根据电泳分离的DNA条带将菌株分为14种类型。98%的菌株含有质粒，DNA分子大小在1 kb ~ 40 kb之间。一个非常有趣的发现是，87%的MRSA共同具有24.3kb的质粒。该质粒在MSSA中很少检出。生化试验结果，i。例如，乳糖和蔗糖发酵，可以将菌株分为四个生物型，这似乎是有限的流行病学价值。在噬菌体分型中，只有10%的MRSA菌株对稀释至IRTD的一种或多种分型噬菌体敏感。而MSSA的分型率为73%。出于流行病学调查的目的，通过凝固酶（无细胞）中和试验（使用I型至VIII型（含）的抗血清）进行分型，结果令人失望，因为98%的菌株属于同一类型，即ii型。以上总结的所有结果使我们得出以下结论：在MRSA感染的流行病学调查中，至少当我们要澄清污染的传播时，对分离株进行“分型“的最有用的方法是结合分析结果，通过PFGE，对用SmaI消化的基因组DNA，血浆DNA分析，特别是大于20 kb的那些，并基于它们发酵乳糖和蔗糖的能力进行生物分型。

项目成果

Matsumoto,Hideki et al: "Evaluation of various typing system for the epidemiological investigation in Staphylococcus saureus infections." Microbiology and Immunology.

Matsumoto, Hideki 等人：“用于金黄色葡萄球菌感染流行病学调查的各种分型系统的评估。”

Matsumoto,Hideki et al.: "Evaluation of various typing ststems for the epidemilogical investigation in Staphylococcus aureus infections." Microbilogy and Immunology.

Matsumoto, Hideki 等人：“金黄色葡萄球菌感染流行病学调查的各种分型系统的评估。”

MATSUMOTO, HIDEKI ET AL: "Evaluation of various typing systems for the epidemiological investigation in Staphylococcus aureus infections." Microbiology and Immunology.

MATSUMOTO、HIDEKI 等人：“金黄色葡萄球菌感染流行病学调查的各种分型系统的评估。”