青岛地区3家'三甲'医院ICU耐亚胺培南革兰氏阴性杆菌碳青霉烯酶基因型研究

摘要

OBJECTIVE: To analyze carbapenemases genotype of imipenem-resistant Gram-negative bacilli in intensive care unit (ICU) of 3 third grade class A hospitals from Qingdao area, so as to provide reference for drug-resistant bacteria infection prevention and treatment in clinic. METHODS: From Jan. 2013 to Jun. 2016, each 60 strains of imipenem-resistant Klebsiella pneumoniae (IRKP), imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant Acinetobacter baumanii (IRAB) were collected from 3 third grade class A hospitals from Qingdao area. Drug sensitivity test was performed by using Kirby-Bauer method. Phenotypes of carbapenemases were determined by Carba NP trial. PCR was applied to amplify carbapenemase gene; Sanger seqnencing method was adopted for bi-directional sequencing; Blast comparison with GenBank database was conducted. RESULTS: Three kinds of imipenem-resistant Gram-negative bacilli showed high drug resistance to majority commonly used antibiotics as piperacillin, cefazolin, imipenem and cilastatin sodium, gentamicin, etc., but were sensitive to polymyxin B (resistance rate of 0). Among 180 drug-resistant strains, there were 52 strains of class A carbapenems, 13 strains of class B carbapenems and 39 strains of class D carbapenems; the detection rates of them were 28. 89％, 7. 22％ and 21. 67％, respectively. There were 52 strains of KPC-2 gene (IRKP), 4 strains of IMP-1 gene (IRPA), 8 strains of VIM-2 gene (7 strains of IRPA, 1 strain of IRAB), 39 strains of OXA-23 gene (IRAB); the detection rates of them were 28. 89％, 2. 22％, 4. 44％, 21. 67％; all strains were not detected 1MP-2, VIM-1, NDM-1, OXA-24, OXA-58 genes. Results of Blast comparison showed that above detected genes were absolutely homology with the corresponding genes in GenBank database. CONCLUSIONS: Drug resistance of imipenem-resistant Gram-negative bacilli in ICU of 3 third grade class A hospitals is serious in this region, which are nearly no-sensitive to most of commonly used antibiotics in clinic. Main genotypes included KPC-2 (K. pneumoniae), OXA-23 (A. baumanii) and IMP-1 and VIM-2 (P. aeruginosa).%目的:分析青岛地区3家"三甲"医院重症监护病房(ICU)耐亚胺培南革兰氏阴性杆菌碳青霉烯酶的基因型,为临床防控和治疗耐药菌感染提供参考.方法:收集2013年1月-2016年6月青岛地区3家"三甲"综合性医院ICU分离的耐亚胺培南肺炎克雷伯菌(IRKP)、耐亚胺培南铜绿假单胞菌(IRPA)、耐亚胺培南鲍曼不动杆菌(IRAB)各60株,采用纸片扩散法进行药敏试验;采用 Carba NP试验确证其碳青霉烯酶表型;采用聚合酶链反应法扩增其碳青霉烯酶基因,应用双脱氧链终止法进行双向测序,并与 GenBank数据库进行Blast比对.结果:3种耐亚胺培南革兰氏阴性杆菌对哌拉西林、头孢唑林、亚胺培南西司他丁钠、庆大霉素等大部分临床常用抗菌药物的耐药率均较高,但对多黏菌素B敏感(耐药率均为0).180株耐药菌株中,A、B、D类碳青霉烯酶阳性菌株分别有52、13、39株,检出率分别为28. 89％、7. 22％、21. 67％.检出KPC-2、IMP-1、VIM-2、OXA-23基因的分别有52株(IRKP)、4株(IRPA)、8株(IRPA7株、IRAB1株)、39株(IRAB),检出率分别为28. 89％、2. 22％、4. 44％、21. 67％;未检出/MP-2、 VIM-1、NDM-1、OXA-24、OXA-58基因.Blast比对结果显示,上述检出基因与GenBank数据库中的已知基因100％同源.结论:该地区3家"三甲"医院ICU耐亚胺培南革兰氏阴性杆菌的耐药情况严重,对大多数临床常用抗菌药物的敏感度均较低.检出的主要基因型包括KPC-2(肺炎克雷伯菌)、OXA-23(鲍曼不动杆菌)、IMP-1和VIM-2(铜绿假单胞菌).