泛耐药鲍曼不动杆菌耐药性和同源性分析

Analysis on the drug resistance and homology of pandrug-resistant Acinetobacter baumannii

目的分析泛耐药鲍曼不动杆菌(PDRAB)的耐药性、同源性及感染病例的临床特征和治疗情况,为指导临床合理用药、控制感染提供依据。方法收集临床分离自住院患者的鲍曼不动杆菌,用法国生物梅里埃VITEK-2 Compact全自动细菌分析仪及药敏纸片法分析菌株耐药性。选取PDRAB感染的病例,用回顾性统计分析方法分析PDRAB感染病例的临床特征及疗效转归;用微量板半定量法检测PDRAB菌株的生物膜形成能力;用脉冲场凝胶电泳法分析PDRAB菌株的同源性。结果共收集鲍曼不动杆菌138株,其中PDRAB菌株11株,占7.97%;选取PDRAB感染的病例10例,其中呼吸重症监护室7例(70%)、普外科2例(20%)、普通重症监护室1例(10%)。10株PDRAB对多黏菌素B敏感率为100%,对目前所有常规的抗菌药物耐药率为100%。138株鲍曼不动杆菌菌株中生物膜阳性7株(5.07%),其中PDRAB 2株、非PDRAB 5株。10株PDRAB菌株共分为7型(A、B、C、D、E、F、G),其中D和E型中的2株菌株的同源性高,其余为散发株。结论呼吸重症监护病房泛耐药现象严重,长期广谱抗菌药物的使用、侵入性诊疗,合并多种基础疾病与感染发生密切相关,多种抗菌药物联合使用对控制PDRAB感染有一定疗效。PDRAB耐药机制复杂,应以呼吸重症监护室为防控重点,同时加强对生物膜阳性菌株所分布的病区的耐药性监测。

Objective To investigate the drug resistance and homology of pandrug-resistant Acinetobacter baumannii （PDRAB） and analyze the clinical characteristics and outcome of its infection, so as to provide reference for the clinical reasonable medication and the prevention of the infection. Methods The drug resistance of Acinetobacter baumannii from inpatients of the hospital was determined by automatic microbial identification system of BioMerieux VITEK-2 Compact and Kirby-Bauer method. Retrospective investigation was performed on the clinical characteristics and therapeutic efficacy turnover of the patients with PDRAB infection. A semiquantitative plate assay was used to test the biofilm-forming ability of PDRAB. The homology of PDRAB was detected by pulsed-field gel electrophoresis. Results A total of 138 Acinetobacter baumannii were isolated,among which 11 （7.97%） isolates were PDRAB. A total of 10 in patients with PDRAB infection were enrolled in the study. The PDRAB infection occurred most frequently in respiratory intensive care unit, 7 （70%） isolates were from respiratory intensive care unit,2 （20%） isolates were from surgical unit,and 1 （10%） isolate was from intensive care unit. The polymyxin sensitivity of all 10 PDRAB was 100% ,but they were resistant to all other antibiotics in routine clinical use, and the resistance rate was 100%. There were 7 （5.07%） biofilm-positive isolates among the 138 Acinetobacter baumannii, 2 isolates were PDRAB, and 5 isolates were non-PDRAB. All of 10 PDRAB were classified into 7 pulsotypes （A, B, C, D, E, F and G）, the homology of 2 isolates of Pulsotype D and Pulsotype E was high, and the others were sporadic isolates. Conclusions Pandrug - resistance is serious in respiratory intensive care unit of the hospital. Pandrug-resistance is closely related to long-term use of broad-spectrum antibiotics, invasive treatment, and patients with multiple underlying diseases. A variety of antimicrobial agents used in combination use have a certain effect on the control of PDRAB infection. It is necessary to strengthen the monitoring of drug resistant and biofilm-positive isolates, especially in respiratory intensive care unit.