A族溶血性链球菌之于β-内酰胺类抗菌药物的检测误区

Errors in the antimicrobial susceptibility test of group A hemolytic Streptococcus forβ-lactam antibiotics

A族β-溶血性链球菌(酿脓链球菌,GAS)对β-内酰胺类抗菌药物敏感。美国临床实验室标准化研究所始终未设定GAS对β-内酰胺类抗菌药物的中介和耐药的折点,并且推荐β-内酰胺类抗菌药物作为治疗GAS感染的一线药物。然而,却有不少报道中出现GAS对β-内酰胺类抗菌药物的中介率、耐药率,且大多来自国内研究和国内主要耐药监测网。回顾国内外GAS对β-内酰胺类抗菌药物所谓“中介”或“耐药”的报道,发现存在诸多疑问,如这些菌株并非真正的“耐药”,而是否真对β-内酰胺类抗菌药物不敏感,而青霉素敏感性降低菌株是否携带青霉素结合蛋白2X突变基因,这些疑问均未得到确切证实。通过本文,以期广大临床医生、药学和微生物学工作者关注GAS及其耐药问题。

Group Aβ-hemolytic Streptococcus(GAS)has always been sensitive toβ-lactam antibiotics.The Clinical and Laboratory Standard Institute(CLSI)had never set a breakpoint for GAS to be"intermediate"or"resistant"toβ-lactam antibiotics,and recommendedβ-lactam antibiotics as the first-line antibiotics for the treatment of GAS infections.However,there are many reports about the"intermediate rate"and"resistance rate"of GAS toβ-lactam antibiotics,most of which were reported by Chinese researchers and the major Chinese bacterial resistance surveillance networks.Through reviewing and summarizing the so-called"intermediary"or"resistance"ofβ-lactam antibiotics by GAS from domestic and abroad,we found that there are many questions.These strains are not actually"resistant".However,issues like whether these strains are really insensitive toβ-lactam antibiotics or whether the penicillin sensitive strains carry the penicillin binding protein 2X mutation gene,remained unknown.We hope that clinicians,pharmacists and microbiologists will pay more attention to GAS and its antibiotics resistance after reading this article.