bronchiectasis

Bronchiectasis is a chronic lung condition characterized by permanent dilation of one or more bronchi due to destruction of the elastic and muscular components of the airway wall. The abnormal airways impair mucociliary clearance, leading to mucus retention and recurrent infections. A cycle of inflammation and infection promotes further airway damage, thickening of the bronchial walls, and chronic cough with daily sputum production.

Causes are varied and can be idiopathic, but common secondary factors include cystic fibrosis, a history of severe pneumonia or tuberculosis, immune deficiencies, and obstructive lesions such as tumors or foreign bodies. Inflammatory conditions such as allergic bronchopulmonary aspergillosis or rheumatoid arthritis–associated lung disease can contribute. Risk factors include childhood infections, smoking, and congenital syndromes affecting airway clearance.

Diagnosis relies primarily on imaging, with high-resolution CT providing the characteristic findings of bronchial dilation, wall thickening, and lack of tapering; the signet ring sign is frequently described. Pulmonary function tests typically show an obstructive pattern, and sputum cultures help identify colonizing or infecting organisms, notably Pseudomonas aeruginosa in many adults. Evaluation for underlying causes—such as genetic testing for cystic fibrosis, immune system assessment, and investigations for airway obstruction—is common.

Management aims to reduce symptoms, prevent exacerbations, and preserve lung function. Key components include regular airway clearance techniques, physical activity, and prompt antibiotic treatment for infections. Some patients may benefit from chronic macrolide therapy for anti-inflammatory effects. Inhaled bronchodilators and, when indicated, inhaled corticosteroids are used. Vaccinations, management of underlying diseases, and, in localized disease, surgical resection or, in advanced cases, lung transplantation, may be considered. The prognosis varies with disease severity and the presence of comorbid conditions.