Department of Public Health Sciences, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy.
J Clin Microbiol. 2010 Apr;48(4):1035-9. doi: 10.1128/JCM.02060-09. Epub 2010 Jan 27.
Achromobacter xylosoxidans is an emerging pathogen increasingly being isolated from respiratory samples of cystic fibrosis (CF) patients. Its role and clinical significance in lung pathogenesis have not yet been clarified. The aim of the present study was to genetically characterize A. xylosoxidans strains isolated from CF patients by use of randomly amplified polymorphic DNA (RAPD) profiles and to look for a possible correlation between RAPD profiles and the patients' clinical features, such as their spirometry values, the presence of concomitant chronic bacterial flora at the time of isolation, and the persistent or intermittent presence of A. xylosoxidans strains. A set of 106 strains of A. xylosoxidans were typed by RAPD analysis, and their profiles were analyzed by agglomerative hierarchical classification (AHC) and associated with the patient characteristics mentioned above by factorial discriminant analysis (FDA). The overall results obtained in this study showed that (i) there is a marked genetic relationship between strains isolated from the same patients at different times, (ii) characteristic RAPD profiles are associated with different predicted classes for forced expiratory volume in 1 s (FEV1%), (iii) some characteristic RAPD profiles are associated with different concomitant chronic flora (CCF) profiles, and (iv) there is a significant division of RAPD profiles into "persistent strains" and "intermittent strains" of A. xylosoxidans. These findings seem to imply that the lung habitats found in CF patients are capable of shaping and selecting the colonizing bacterial flora, as seems to be the case for the A. xylosoxidans strains studied.
木糖氧化无色杆菌是一种新兴的病原体,越来越多地从囊性纤维化(CF)患者的呼吸道样本中分离出来。其在肺部发病机制中的作用和临床意义尚不清楚。本研究的目的是通过随机扩增多态性 DNA(RAPD)图谱对从 CF 患者中分离出的木糖氧化无色杆菌菌株进行遗传特征分析,并寻找 RAPD 图谱与患者临床特征之间的可能相关性,如他们的肺活量值、分离时同时存在的慢性细菌菌群、以及木糖氧化无色杆菌菌株的持续或间歇性存在。使用 RAPD 分析对 106 株木糖氧化无色杆菌菌株进行分型,并通过凝聚层次分类(AHC)对其图谱进行分析,并通过因子判别分析(FDA)与上述患者特征相关联。本研究的总体结果表明:(i)同一患者不同时间分离的菌株之间存在明显的遗传关系;(ii)特征性 RAPD 图谱与 1 秒用力呼气量(FEV1%)的不同预测类别相关;(iii)一些特征性 RAPD 图谱与不同的同时存在的慢性菌群(CCF)图谱相关;(iv)RAPD 图谱可分为木糖氧化无色杆菌的“持续菌株”和“间歇性菌株”。这些发现似乎表明,CF 患者肺部的栖息地能够塑造和选择定植菌群,就像研究中的木糖氧化无色杆菌菌株一样。