Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Ciber de Enfermedades Respiratorias (CIBERES), Hospital Clínic, Barcelona, Spain.
Respir Med. 2013 Jan;107(1):10-22. doi: 10.1016/j.rmed.2012.10.024. Epub 2012 Dec 4.
Microorganisms, particularly bacteria, are frequently found in the lower airways of COPD patients, both in stable state and during exacerbations. The host-pathogen relationship in COPD is a complex, dynamic process characterised by frequent changes in pathogens, their strains and loads, and subsequent host immune responses. Exacerbations are detrimental events in the course of COPD and evidence suggests that 70% may be caused by microorganisms. When considering bacterial exacerbations, recent findings based on molecular typing have demonstrated that the acquisition of new strains of bacteria or antigenic changes in pre-existing strains are the most important triggers for exacerbation onset. Even in clinically stable COPD patients the presence of microorganisms in their lower airways may cause harmful effects and induce chronic low-grade airway inflammation leading to increased exacerbation frequency, an accelerated decline in lung function and impaired health-related quality of life. Besides intraluminal localisation in the distal airways, bacteria can be found in the bronchial walls and parenchymal lung tissue of COPD patients. Therefore, the isolation of pathogenic bacteria in stable COPD should be considered as a form of chronic infection rather than colonisation. This new approach may have important implications for the management of patients with COPD.
微生物，特别是细菌，经常在 COPD 患者的下呼吸道中被发现，无论是在稳定期还是在加重期。COPD 中的宿主-病原体关系是一个复杂的、动态的过程，其特点是病原体及其菌株和负荷经常发生变化，以及随后的宿主免疫反应。加重是 COPD 病程中的不利事件，有证据表明，70%可能由微生物引起。在考虑细菌加重时，基于分子分型的最新发现表明，新菌株的获得或原有菌株的抗原性变化是加重发作的最重要触发因素。即使在临床稳定的 COPD 患者中，下呼吸道中微生物的存在也可能造成有害影响，并导致慢性低度气道炎症，从而增加加重频率、加速肺功能下降和损害健康相关生活质量。除了在远端气道的腔内定位外，细菌还可以在 COPD 患者的支气管壁和肺实质组织中被发现。因此，稳定期 COPD 中致病性细菌的分离应被视为一种慢性感染形式，而不是定植。这种新方法可能对 COPD 患者的管理具有重要意义。
