宁夏地区临床分离肠球菌属对高浓度庆大霉素耐药基因的研究

Resistant genes to high-level gentamicin of enterococcus in Ningxia

目的研究分析医院2007-2009年临床分离耐高浓度庆大霉素肠球菌的耐药性及耐药基因流行分布。方法采用K-B纸片扩散法进行药敏试验,PCR方法检测aac(6′-)Ie-aph(2″-)Ia、aph(2″-)Ib、aph(2″-)Ic、aph(2″-)Id、aph(3′-)IIIa基因。结果 383株肠球菌属中以屎肠球菌和粪肠球菌最多见,分别占47.0%和38.6%,其中耐高浓度庆大霉素屎肠球菌和粪肠球菌分别为79.3%和44.6%;耐药基因检测显示,aac(6′-)Ie-aph(2′-)Ia基因的阳性率为62.8%,其中143株耐高浓度庆大霉素屎肠球菌中129株含有aac(6′-)Ie-aph(2″-)Ia基因,66株耐高浓度庆大霉素粪肠球菌均含有aac(6′)-Ie-aph(2″-)Ia基因,未检测到aac(6′-)Ie-aph(2″)-Ib、aac(6′-)Ie-aph(2″-)Ic和aac(6′-)Ie-aph(2″-)Id基因。结论 aac(6′)-Ie-aph(2″-)Ia基因是医院临床分离耐高浓度庆大霉素肠球菌的惟一耐药基因,监测肠球菌属对高浓度氨基糖苷类抗菌药物的耐药性及检测高浓度庆大霉素耐药基因,为临床治疗肠球菌属感染提供依据。

OBJECTIVE To study the drug resistance and high-level gentamicin resistance genes of Enterococcus from clinical infective patients in 2007-2009.METHODS The drug sensitive test was carried out by KB method.The high-level gentamicin resistance genes of aac（6′）-Ie-aph（2″）-Ia,aph（2″）-Ib,aph（2″）-Ic,aph（2″）-Id were detected by PCR.RESULTS A total of 383 enterococcus isolates were isolated from hospital during 2007-2009.High-level gentamicin resistance was found in 79.3% of E.faecium and 44.6% of E.faecalis respectively.The positive rate of high-level gentamicin resistance genes of aac（6′）-Ie-aph（2″）-Ia was 62.8%,aac（6′）-Ie-aph（2″）-Ib,aac（6′）-Ie-aph（2″）-Ic and aac（6′）-Ie-aph（2″）-Id were not detected out.CONCLUSIONS aac（6′）-Ie-aph（2″）-Ia is only detected out in high-level gentamicin resistant Enterococcus.Understanding the resistance pattern of high-level aminoglycoside resistance and detecting high-level gentamicin resistance genes in Enterococcus are important for rational treatment of infections caused by Enterococcus.