鲍氏不动杆菌的生物膜形成能力及相关特征分析

Biofilm formation of Acinetobacter baumannii and its clinical characteristics

目的比较患者与环境分离的鲍氏不动杆菌(ABA)生物膜形成能力,分析感染/定植生物膜ABA患者的流行病学和临床特征,探讨生物膜在ABA感染/定植过程中的作用。方法采用结晶紫定量法检测2011年7月-2012年6月医院ICU住院患者送检标本分离的110株ABA及2012年7月外科ICU环境采样分离61株ABA的生物膜形成能力,采用SPSS19.0软件进行χ2检验,比较ICU患者和环境分离ABA形成生物膜的能力。结果 110株患者分离ABA中73株可形成生物膜,占66.4%;61株环境分离株中,24株为产生物膜株,占39.3%;尿液、血液和导管标本中分离的ABA产生物膜阳性率较高,分别为100.0%、87.5%和75.0%;呼吸机插管患者分离的ABA中产生物膜阳性率为78.3%,非呼吸机插管患者ABA产生物膜阳性率为54.3%,差异有统计学意义(P<0.05)。结论临床ABA生物膜形成能力明显高于环境分离株,说明形成生物膜的ABA更易引起人体的定植和感染,形成生物膜是ABA感染过程中的致病机制之一。

OBJECTIVE To compare the biofilm formation of Acinetobacter baumannii isolated from patients and en- vironment and analyze the epidemiological and clinical characteristics of the patients with A. baumannii infection or colonization so as to explore the role of biofilm in the A. baumannii infection or colonication. METHODS Totally 110 strains of A. baurnannii isolated from the submitted specimens of the ICU hospitalized patients from Jul 2011 to Jun 2012 and 61 strains of A. baumannii isolated from the environment of surgical ICU in Jul 2012 were collect- ed, then the biofilm formations of those isolates were tested by means of crystal violet quantitative method, the chi-square test was performed with the use of SPSS19.0 software, and the ability of biofilm formation was com- pared between the A. baurnannii strains isolated from the ICU patients and those from the environment. RESULTS Of the 110 strains of A. baurnannii isolated from the patients, 73 strains could form the biofilm, accounting for 66.4% ; of the 61 strains of A. baumannii isolated from the environment, 24 strains could form the biofilm, ac- counting for 39.3M. The positive rates of biofilm formation of the A. baurnannii strains isolated from the urine, blood, or catheter specimens were relatively high, which were 100.0%, 87.5~, and 75.0%, respectively. The positive rate of biofilm formation of the A. baumannii strains isolated from the patients who underwent the ventila- tor catheter indwelling was 78.3~, significantly higher than 54.3% of those isolated from the patients who did not undergo the ventilator catheter indwelling, and there was statistically significant difference （P〈0.05）. CONCLUSION The ability of biofilm formation of the clinical isolates of A. baumannii is significantly higher than that of the isolates from the environment, which indicates that the A. baumannii strains with formed biofilm are more likely to cause the colonization or infections in human beings and that the biofilm formation is one of the pathogenesis of A. baumannii infection.