Sharma Sat, Anthonisen Nicholas
Section of Respirology, Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
Treat Respir Med. 2005;4(3):153-67. doi: 10.2165/00151829-200504030-00001.
Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a common occurrence and characterize the natural history of the disease. Over the past decade, new knowledge has substantially enhanced our understanding of the pathogenesis, outcome and natural history of AECOPD. The exacerbations not only greatly reduce the quality of life of these patients, but also result in hospitalization, respiratory failure, and death. The exacerbations are the major cost drivers in consumption of healthcare resources by COPD patients. Although bacterial infections are the most common etiologic agents, the role of viruses in COPD exacerbations is being increasingly recognized. The efficacy of antimicrobial therapy in acute exacerbations has established a causative role for bacterial infections. Recent molecular typing of sputum isolates further supports the role of bacteria in AECOPD. Isolation of a new strain of Haemophilus influenzae, Moraxella catarrhalis, or Streptococcus pneumoniae was associated with a considerable risk of an exacerbation. Lower airway bacterial colonization in stable patients with COPD instigates airway inflammation, which leads to a protracted self-perpetuating vicious circle of progressive lung damage and disease progression. A significant proportion of patients treated for COPD exacerbation demonstrate incomplete recovery, and frequent exacerbations contribute to decline in lung function. The predictors of poor outcome include advanced age, significant impairment of lung function, poor performance status, comorbid conditions and history of previous frequent exacerbations requiring antibacterials or systemic corticosteroids. These high-risk patients, who are likely to harbor organisms resistant to commonly used antimicrobials, should be identified and treated with antimicrobials with a low potential for failure. An aggressive management approach in complicated exacerbations may reduce costs by reducing healthcare utilization and hospitalization.
慢性阻塞性肺疾病急性加重（AECOPD）很常见，是该疾病自然病程的特征。在过去十年中，新知识极大地增进了我们对AECOPD发病机制、结局和自然病程的理解。急性加重不仅会大幅降低这些患者的生活质量，还会导致住院、呼吸衰竭和死亡。急性加重是慢性阻塞性肺疾病患者消耗医疗资源的主要费用驱动因素。虽然细菌感染是最常见的病因，但病毒在慢性阻塞性肺疾病急性加重中的作用也日益受到认可。抗菌治疗在急性加重中的疗效确立了细菌感染的致病作用。近期痰液分离株的分子分型进一步支持了细菌在AECOPD中的作用。分离出新的流感嗜血杆菌、卡他莫拉菌或肺炎链球菌菌株与急性加重的相当大风险相关。慢性阻塞性肺疾病稳定期患者的下呼吸道细菌定植会引发气道炎症，进而导致持续的自我延续恶性循环，造成进行性肺损伤和疾病进展。相当一部分接受慢性阻塞性肺疾病急性加重治疗的患者恢复不完全，频繁急性加重会导致肺功能下降。预后不良的预测因素包括高龄、肺功能严重受损、身体状况差、合并症以及既往频繁急性加重需要使用抗菌药物或全身用糖皮质激素的病史。这些可能携带对常用抗菌药物耐药的病原体的高危患者，应予以识别并用失败可能性低的抗菌药物进行治疗。对复杂急性加重采取积极的管理方法可能通过减少医疗资源利用和住院来降低成本。
