对下呼吸道感染鲍曼不动杆菌氨基糖苷类耐药基因检测

目的:探讨鲍曼不动杆菌对氨基糖苷类抗菌药物的耐药机制。方法:收集下呼吸道感染患者痰液中分离出的鲍曼不动杆菌共136株,采用K-B纸片法测定对13种抗菌药物的敏感性。用聚合酶链反应(PCR)方法检测耐氨基糖苷类抗菌药物的鲍曼不动杆菌的8种氨基糖苷类修饰酶基因(AME)。结果:32株耐阿米卡星和庆大霉素的鲍曼不动杆菌对多粘菌素B、替加环素、头孢哌酮/舒巴坦、米诺环素敏感率分别为93.8%、81.3%、62.5%、62.5%,对其他15种抗菌药物的耐敏感率均低于18.7%。对32株耐氨基糖苷类的鲍曼不动杆菌8种氨基糖苷酶基因扩增共获得4种氨基糖苷类修饰酶基因,分别为15株aac(3)-I、32株aac(6′)-Ib、32株aac(6′)-Ⅱ、29株ant(3″)-I。结论:对氨基糖苷类耐药的鲍曼不动杆菌93.75%为多重耐药鲍曼不动菌(MDRAB)。泛耐药鲍曼不动杆菌对多粘菌素B、替加环素、头孢哌酮/舒巴坦、米诺环素敏感性较高。氨基糖苷酶aac(3)-I、aac(6′)-Ib、aac(6′)-Ⅱ、an(t3″)-I基因广泛存在于耐氨基糖苷类的鲍曼不动杆菌中。

Identification of aminoglycoside modifying enzymes from Acinetobacter baumannii in patients with lower respiratory tract infection

Objective: To explore the resistante mechanism of Acinetobacter baumannii(Ab) to aminoglycoside antibiotics.Methods: Kirby-Bauer method was performed to detect the sensitivity of 13 kinds of antibiotics.Eight aminoglycosides modifying enzymes(AME) of Ab resisting to aminoglycoside antimicrobial agents were detected by polymerase chain reaction(PCR).Results: The susceptibility rates of 32 strains Ab with amikacin-resistant and gentamicin-resistant to polymyxin B,tigecycline,cefperazone-sulbactam,Minocycline were 93.8%,81.3%,62.5%,62.5%,respectively.The susceptibility rates of 32 strains to other antibiotics were less than 18.7%.4 stains of aminoglycosides modifying enzymes were isolated from 32 strains Ab with amikacin-resistant and gentamicin-resistant,they were aac(3)-I(n=15),aac(6′)-Ib(n=32),aac(6′)-Ⅱ(n=32),ant(3″)-I(n=29).Conclusion: 93.75% of aminoglycoside-resistant Ab are multidrug-resistant Acinetobacter baumannii(MDRAB).MDRAB are sensitivity to polymyxin B,tigecycline,cefperazone-sulbactam,minocycline.Aminoglycosides modifying enzymes gene existe widely in minoglycoside-resistant Ab in clinic.