Aktas Zerrin, Aridogan Aslihan, Kayacan Cigdem Bal, Aydin Derya
Department of Microbiology and Clinical Microbiology, Medical Faculty of Istanbul, Istanbul University, Istanbul 34300, Turkey.
J Microbiol. 2007 Aug;45(4):286-90.
The purpose of this study was to investigate the prevalence and genetic mechanisms of erythromycin resistance in staphylococci. A total of 102 erythromycin resistant non-duplicate clinical isolates of staphylococci [78 coagulase negative stapylococci (CNS), 24 Staphylococcus aureus] were collected between October 2003 and August 2004 in Istanbul Faculty of Medicine in Turkey. The majority of the isolates were from blood and urine specimens. Antimicrobial susceptibilities were determined by the agar dilution procedure and the resistance phenotypes by the double disk induction test. A multiplex PCR was performed, using primers specific for erm(A), erm(B), erm(C), and msrA genes. Among the 78 CNS isolates, 57.8% expressed the MLSB-constitutive, 20.6% the MLSB-inducible, and 21.6% the MSB phenotypes. By PCR, 78.2% of these isolates harbored the erm(C) gene, 8.9% erm(A), 6.4% erm(B), and 11.5% msrA genes. In S. aureus, the constitutive MLSB (58.3%) was more common than the inducible phenotype (20.8%). erm(A) was detected in 50% and erm(C) in 62.5% of the isolates, while 37.5% contained both erm(A) and erm(C). erm(C)-associated macrolide resistance was the most prevalent in CNS, while erm(C) and erm(A, C) was the most prevalent in S. aureus.
本研究的目的是调查葡萄球菌中红霉素耐药性的流行情况及遗传机制。2003年10月至2004年8月期间，在土耳其伊斯坦布尔医学院收集了102株非重复的红霉素耐药葡萄球菌临床分离株[78株凝固酶阴性葡萄球菌（CNS），24株金黄色葡萄球菌]。大多数分离株来自血液和尿液标本。采用琼脂稀释法测定抗菌药物敏感性，采用双纸片诱导试验测定耐药表型。使用针对erm(A)、erm(B)、erm(C)和msrA基因的引物进行多重PCR。在78株CNS分离株中，57.8%表现为组成型MLSB，20.6%为诱导型MLSB，21.6%为MSB表型。通过PCR检测，这些分离株中78.2%携带erm(C)基因，8.9%携带erm(A)基因，6.4%携带erm(B)基因，11.5%携带msrA基因。在金黄色葡萄球菌中，组成型MLSB（58.3%）比诱导型表型（20.8%）更常见。50%的分离株检测到erm(A)，62.5%检测到erm(C)，37.5%同时含有erm(A)和erm(C)。与erm(C)相关的大环内酯类耐药在CNS中最为普遍，而erm(C)和erm(A, C)在金黄色葡萄球菌中最为普遍。
