老年慢性阻塞性肺疾病患者鲍氏不动杆菌的分子流行特征

目的 揭示医院老年慢性阻塞性肺疾病(COPD)患者中鲍氏不动杆菌分子流行的主要特征.方法 筛选2009-2011年老年COPD患者中分离的57株鲍氏不动杆菌为试验菌株；使用Whonet5.6软件分析其药敏结果；应用基于序列分型的多重PCR方法鉴定鲍氏不动杆菌的主要流行克隆谱系;利用限制性内切酶ApaI对试验菌株基因组DNA进行酶切和脉冲场凝胶电泳(PFGE)分析；应用PCR及测序方法检测10种耐药相关基因,分析并命名相应的耐药基因谱.结果 鲍氏不动杆菌除了对多黏菌素B的耐药率为8.8％外,对其他15种抗菌药物均具有较高的耐药率,为70.2％～98.2％;主要克隆谱系以RGP1序列型为主,所占的比例高达59.6％；在87.0％的相似性水平上,可大致分为18种PFGE图谱,其中主要型别为A型；共发现存在有15种耐药基因谱,其中多药耐药谱RGP1所占的比例高达52.63％.结论 在老年COPD患者中分离的鲍氏不动杆菌主要的流行克降谱系与欧洲克隆谱系Ⅱ具有高度的同源性；多药耐药相关基因的携带率较高,在具有不同遗传背景的鲍氏不动杆菌中存在有水平转移.

Molecular epidemiology of Acinetobacter baumannii strains from elderly patients with chronic obstructive pulmonary disease

OBJECTIVE To investigate the molecular epidemiology of Acinetobacter baumannii isolates from the elderly patients with chronic obstructive pulmonary disease(COPD) in the hosptial.METHODS Fifty-seven A.baumannii isolates were collected during the period between 2009 and 2011.All isolates were subjected to the Whonet 5.6 software to analyze the susceptibility,and the most prevalent clone genealogy of A.baumannii was identified with the multiple PCR based on the genotype sequencing,the enzyme digestion and PFGE trial of genome DNA of the study strains were performed;PCR and gene sequencing were used to detect the 10 drug resistance-related genes,the corresponding drug resistance gene spectra were analyzed and named.RESULTS The drug resistance rate to the 15 antibiotics tested varied between 70.2% and 98.2% except the drug resistance rate to polymycin B was 8.8%;the majority of isolates(59.6%) belonged to the defined RGP1;all isolates were broadly classified into 18 genotypes by PFGE typing with a similarity coefficient of 87.0%,and PFGE type A was a predominant clone,accounting for 59.65%;there were totally 15 types of resistance gene spectra detected,among which RGP1 accounted for 52.63%.CONCLUSION The prevalent clonal lineages of A.baumannii isolated from the elderly COPD patients may be highly homologous to European clone Ⅱ;the carrying rate of the multidrug-resistance realted genes which can horizontally transfer through the A.baumannii strains with various genetic backgrounds is high.