Leski T, Oliveira D, Trzcinski K, Sanches I S, Aires de Sousa M, Hryniewicz W, de Lencastre H
Molecular Genetics Unit, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
J Clin Microbiol. 1998 Dec;36(12):3532-9. doi: 10.1128/JCM.36.12.3532-3539.1998.
We report on a study of 158 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates obtained from 1990 to 1996 in 18 different hospitals in Poland. All isolates were recovered from infection and carriage sites of patients, carriage sites of health care personnel, and hospital environment samples. Fifty-seven MRSA strains described here were studied previously and these were divided into two different clusters according to the degree of heterogeneity of methicillin resistance expression. The aim of this study was to extend the correlation between the two clusters and identify the clonal identities among all isolates by a combination of different methodologies: (i) analysis of mecA polymorphs and Tn554 insertion patterns and (ii) determination of pulsed-field gel electrophoresis patterns of chromosomal SmaI digests. Ninety-seven of 158 strains showed a heterogeneous expression of resistance to methicillin. Among these, 75 (77.3%) were ClaI-mecA type I, ClaI-Tn554 type NH (NH, no homology with transposon Tn554), and pulsed-field gel electrophoresis (PFGE) pattern A (I::NH::A); 10 isolates were III::B::M (10.3%); and the remaining clones included a few or single isolates. The isolates with homogeneous expression of resistance to methicillin (n = 61) were predominantly ClaI-mecA type III (49 of 61 [80.3%]) but had great variability in their ClaI-Tn554 and PFGE patterns. This study confirmed the existence of two main clusters of MRSA in Poland.
我们报告了一项对1990年至1996年期间从波兰18家不同医院获得的158株耐甲氧西林金黄色葡萄球菌（MRSA）临床分离株的研究。所有分离株均从患者的感染和携带部位、医护人员的携带部位以及医院环境样本中分离得到。此处描述的57株MRSA菌株先前已进行过研究，并根据甲氧西林耐药性表达的异质性程度分为两个不同的簇。本研究的目的是通过不同方法的组合扩展这两个簇之间的相关性，并确定所有分离株的克隆身份：（i）分析mecA多态性和Tn554插入模式，以及（ii）确定染色体SmaI酶切产物的脉冲场凝胶电泳图谱。158株菌株中有97株表现出对甲氧西林的异质性耐药表达。其中，75株（77.3%）为ClaI-mecA I型、ClaI-Tn554 NH型（NH，与转座子Tn554无同源性），脉冲场凝胶电泳（PFGE）图谱为A（I::NH::A）；10株为III::B::M型（10.3%）；其余克隆包括少数或单个分离株。对甲氧西林耐药表达均一的分离株（n = 61）主要为ClaI-mecA III型（61株中的49株[80.3%]），但其ClaI-Tn554和PFGE图谱具有很大变异性。本研究证实了波兰存在两个主要的MRSA簇。
