Petinaki E, Miriagou V, Tzouvelekis L S, Pournaras S, Hatzi F, Kontos F, Maniati M, Maniatis A N
Department of Microbiology, School of Medicine, University of Thessaly, Larissa, Greece
Int J Antimicrob Agents. 2001 Jul;18(1):61-5. doi: 10.1016/s0924-8579(01)00327-2.
A total of 250 consecutive Staphylococcus aureus clinical isolates were collected during the period 1999-2000 from the five major hospitals of the district of Thessaly (Central Greece). Thirty seven (14.8%) of the isolates were mecA-positive (MRSA) in a PCR-based assay; all exhibited resistance to oxacillin (agar dilution MICs > or =4 mg/L) and were also resistant to multiple antibiotics. Most of the MRSA isolates had been collected in the intensive care units and the surgical wards of the participating hospitals in a sporadic fashion. The MRSA incidence found here was significantly lower than reported in previous studies from Greece. Molecular typing by PFGE showed that the MRSA isolates were distributed between three pulsotypes. Evaluation of various conventional methods for assessing methicillin resistance showed that oxacillin agar dilution and immunological detection of PBP2a with the Slidex MRSA Detection kit were the most reliable in this setting. Misclassifications of isolates exhibiting low-level resistance (oxacillin MIC 2-4 mg/L) occurred with the salt agar screen, the oxacillin disk diffusion and the ATB Staph System methods.
1999年至2000年期间，从希腊中部色萨利地区的五家主要医院收集了250株连续的金黄色葡萄球菌临床分离株。在基于PCR的检测中，37株（14.8%）分离株mecA呈阳性（耐甲氧西林金黄色葡萄球菌）；所有分离株均对苯唑西林耐药（琼脂稀释法测得的最低抑菌浓度≥4mg/L），并且对多种抗生素耐药。大多数耐甲氧西林金黄色葡萄球菌分离株是以散发性方式从参与研究的医院的重症监护病房和外科病房收集到的。这里发现的耐甲氧西林金黄色葡萄球菌发病率明显低于希腊以往研究报告的发病率。脉冲场凝胶电泳分子分型显示，耐甲氧西林金黄色葡萄球菌分离株分布在三种脉冲型之间。对评估甲氧西林耐药性的各种传统方法进行评估表明，在这种情况下，苯唑西林琼脂稀释法和使用Slidex MRSA检测试剂盒对PBP2a进行免疫检测是最可靠的。盐琼脂筛选法、苯唑西林纸片扩散法和ATB葡萄球菌系统方法会对表现出低水平耐药性（苯唑西林最低抑菌浓度为2 - 4mg/L）的分离株产生错误分类。
