[Bronchiectasis--current aspects of an old disease]

Bronchiectasis is pathologically defined as an abnormal and permanent dilatation of one or several bronchi. There are localized and generalized types of bronchiectasis. A vicious circle hypothesis, including an initial insult to the lower airways, impaired mucociliary clearance, microbial colonization/infection, bronchial obstruction and a local inflammatory response, has been proposed to explain the damage to the bronchial tree and the adjacent lung parenchyma. The clinical picture is variable and affected individuals might be asymptomatic or suffer from severe respiratory failure. Daily sputum production is the most common, though unspecific symptom of bronchiectasis. Other common symptoms are hemoptysis and recurrent episodes of sputum purulence, fever and pleurisy. Occasionally, major, life-threatening hemoptysis from a ruptured bronchial artery occurs. Infectious complications, e.g. lung abscess, empyema, brain abscess, and secondary amyloidosis are rarely seen today. The chest radiograph reveals changes suggestive of bronchiectasis in the majority of patients with clinically important disease. High resolution computed tomography of the lung has almost completely replaced bronchography for diagnosis, the latter rarely being of value if surgery is contemplated. No etiology is identified in about one- to two-thirds of the patients, although there are many diseases eventually associated with bronchiectasis. Prevention and therapy of underlying diseases are most important. Traditionally, the therapy of symptomatic bronchiectasis is based on antibiotics, antibronchoobstructive medication, and chest physical therapy. Surgical resection is the treatment of choice for localized symptomatic disease. Bilateral lung transplantation should be considered in younger patients with severe, generalized bronchiectasis and respiratory failure. Prospective, randomized, largescale trials supporting any of the different treatment strategies are not available, but antibiotics and surgery probably have improved the long-term outcome of many patients with bronchiectasis. In this review, some recent findings regarding the classification, pathogenesis, pathology, etiology, diagnosis, treatment, and prognosis of bronchiectasis are discussed.