Division of Microbiological Diagnostic Laboratory, Central Clinical Laboratory, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary.
Eur J Clin Microbiol Infect Dis. 2011 May;30(5):691-9. doi: 10.1007/s10096-010-1142-5. Epub 2011 Jan 11.
The purpose of this study was to quantify the impact of Staphylococcus haemolyticus in the epidemiology of the blood stream infection (BSI) and to characterize the rates and quantitative levels of resistance to antistaphylococcal drugs. During an eight-year period, 2967 BSIs of the patients hospitalized in different clinical departments of the Semmelweis University, Budapest, Hungary were analyzed. One hundred eighty-four were caused by S. haemolyticus, amounting to 6% of all infections. The antibacterial resistance of S. haemolyticus isolates was investigated by the broth microdilution method, vancomycin agar screen, population analysis profile and PCR for mecA, vanA and vanB genes detection. Epidemiological investigation was processed by determining phenotypic antibiotic resistance patterns and PFGE profiles. Extremely high MIC levels of resistance were obtained to oxacillin, erythromycin, clindamycin, gentamicin and ciprofloxacin. The incidence of teicoplanin reduced susceptibility revealed 32% without possessing either the vanA or vanB gene by the strains. PFGE revealed 56 well-defined genotypes indicating no clonal relationship of the strains. The propensity of S. haemolyticus to acquire resistance and its pathogenic potential in immunocompromised patients, especially among preterm neonates, emphasise the importance of species level identification of coagulase-negative staphylococci and routinely determine the MIC of proper antibacterial agents for these isolates.
本研究旨在量化溶血葡萄球菌在血流感染（BSI）流行病学中的影响，并对其对抗葡萄球菌药物的耐药率和定量水平进行特征描述。在 8 年期间，分析了匈牙利布达佩斯塞梅尔维斯大学不同临床科室住院患者的 2967 例 BSI。其中 184 例由溶血葡萄球菌引起，占所有感染的 6%。通过肉汤微量稀释法、万古霉素琼脂筛选法、群体分析谱和 mecA、vanA 和 vanB 基因检测的 PCR 方法研究了溶血葡萄球菌分离株的抗菌耐药性。通过确定表型抗生素耐药模式和 PFGE 图谱进行了流行病学调查。对青霉素、红霉素、克林霉素、庆大霉素和环丙沙星的耐药 MIC 水平极高。未携带 vanA 或 vanB 基因的菌株对替考拉宁的敏感性降低率为 32%。PFGE 显示了 56 种明确的基因型，表明菌株之间没有克隆关系。溶血葡萄球菌获得耐药性的倾向及其在免疫功能低下患者中的致病潜力，特别是在早产儿中的作用，强调了对凝固酶阴性葡萄球菌进行种水平鉴定和常规测定这些分离株适当抗菌药物 MIC 的重要性。
