耐甲氧西林金黄色葡萄球菌耐药机制及检测方法研究进展

Progress of research on the resistance mechanism and detection methods of methicillin-resistant Staphylococcus aureus

耐甲氧西林金黄色葡萄球菌(MRSA)是目前引起医疗感染最常见的多重耐药菌之一,所致感染传播速度快,治疗困难,对医院感染的控制提出了新的挑战。葡萄球菌染色体mec基因盒遗传元件(SCCmec)的可转移性是感染呈散发或暴发流行的重要原因,SCCmec携带mecA和mecC耐药基因,分别编码青霉素结合蛋白2a(PBP2a)和青霉素结合蛋白2c(PBP2c),其与β内酰胺类抗菌药物的亲和力极低,从而产生耐药性。在agr系统与sar系统的调控下,MRSA可形成生物膜,发挥屏障作用,可有效抵御抗菌药物对细菌的杀伤。通过耐药基因与生物膜的共同作用,使得MRSA的耐药机制更加复杂。本文就SCCmec的基本结构与功能、MRSA的耐药机制以及检测方法等研究进展做一综述,以期为MRSA感染的控制及临床治疗提供参考。

Methicillin-resistant Staphylococcus aureus(MRSA)is one of the most common multiple drug-resistant bacteria causing medical infection.It spreads quickly and is difficult to be killed,which poses a new challenge to the control of nosocomial infection.The transferability of the staphylococcal cassette chromosome mec(SCCmec)is an important reason for sporadic or outbreaks of infection.SCCmec carries mecA and mecC drug-resistant genes encoding PBP2 a and PBP2 c,which have very low affinity toβ-lactam antibiotics,resulting in drug resistance.Under the regulation of agr system and sar system,biofilm is formed in MRSA and plays a barrier role in the protection of MRSA from being killed by antimicrobials.The combination of drug-resistant genes and biofilms make the mechanism of drug-resistance of MRSA more complex.This article reviews the basic structure and function of SCCmec,the drug-resistance mechanism and detection methods of MRSA,in order to provide reference for the control and clinical treatment of MRSA infection.