呼吸机相关感染患者鲍曼不动杆菌氨基糖苷类耐药基因检测及耐药性分析

Aminoglycosides resistance genes and drug resistance to Acinetobacter baumannii in patients with ventilator-associated infection

目的探讨呼吸机相关感染患者鲍曼不动杆菌氨基糖苷类抗菌药物的耐药机制。方法收集2018年7月至2020年7月郑州大学附属郑州市中心医院呼吸机相关感染患者痰标本中分离出的鲍曼不动杆菌150株,采用K-B纸片法检测13种抗菌药物的敏感性。采用聚合酶链反应检测耐氨基糖苷类抗菌药物的鲍曼不动杆菌的氨基糖苷类修饰酶基因。结果150株鲍曼不动杆菌对头孢哌酮、哌拉西林、亚胺培南的敏感率较高,分别为88.00%、72.00%、72.00%。36株对阿米卡星和庆大霉素耐药的鲍曼不动杆菌对头孢他啶、环丙沙星、阿米卡星、庆大霉素、奈替米星、妥布霉素、复方新诺明、头孢吡肟、哌拉西林、美罗培南、左氧氟沙星、四环素、氨曲南及莫西沙星的耐药率较高,均>80.00%;对多粘菌素B、替加环素的敏感率较高,分别为94.44%、80.56%。对36株耐氨基糖苷类的鲍曼不动杆菌氨基糖苷酶的基因进行扩增,获得aac(3)-Ⅰ、aac(6’)-Ib、aac(6’)-Ⅱ及ant(3’’)-I 4种氨基糖苷类修饰酶基因。结论氨基糖苷酶aac(3)-I、aac(6’)-Ib、aac(6’)-Ⅱ及ant(3’’)-I基因广泛存在于耐氨基糖苷类鲍曼不动杆菌中,临床应加强抗生素合理使用,减少鲍曼不动杆菌耐药。

Objective To investigate the drug resistance mechanism of aminoglycoside antibiotics against Acinetobacter baumannii in patients with ventilator-associated infection.Methods A total of 150 strains of Acinetobacter baumannii were isolated from sputum samples from patients with ventilator-related infection treated in Zhengzhou Central Hospital Affiliated to Zhengzhou University from July 2018 to July 2020.The sensitivities to 13 antibacterial drugs were detected by the K-B disc method.The polymerase chain reaction method was used to detect the aminoglycosides-modifying enzymes(AME)genes of aminoglycosides-resistant Acinetobacter baumannii.Results It was found that the 150 strains of Acinetobacter baumannii were sensitive to cefoperazone,piperacillin,and imipenem;and the sensitivity rates were 88.00%,72.00%,and 72.00%,respectively.Thirty-six strains of amikacin and gentamicin resistant Acinetobacter baumannii had high resistance rates to ceftazidime,ciprofloxacin,amikacin,gentamicin,netilmicin,tobramycin,compound sinomin,cefepime,piperacillin,meropenem,levofloxacin,tetracycline,aztreonam and moxifloxacin,which were all higher than 80.00%.Moreover,the sensitivities of 36 strains of amikacin and gentamicin resistant Acinetobacter baumannii to polymyxin B and tigecycline were high(94.44%and 80.56%).Aminoglycosides genes of 36 strains of aminoglycosides resistant Acinetobacter baumannii were amplified,and finally,4 AME genes were obtained,including aac(3)-I,aac(6’)-Ib,aac(6’)-Ⅱand ant(3’’)-I.Conclusions AME genes,including aac(3)-I,aac(6’)-Ib,aac(6’)-II and ant(3’’)-I,widely exist in aminoglycosides resistant Acinetobacter baumannii.Clinically,rational antibiotic use should be strengthened to reduce drug resistance of Acinetobacter baumannii.