ESSENTIALS OF DIAGNOSIS
Chronic productive cough with dyspnea and wheezing.
Radiographic findings of dilated, thickened airways and scattered, irregular opacities.
Bronchiectasis is a congenital or acquired disorder of the large bronchi characterized by permanent, abnormal dilation and destruction of bronchial walls. It may be caused by recurrent inflammation or infection of the airways and may be localized or diffuse. Cystic fibrosis causes about half of all cases of bronchiectasis. Other causes include (1) lung infections (tuberculosis, fungal infections, lung abscess, pneumonia), (2) immunodeficiencies (congenital or acquired hypogammaglobulinemia; common variable immunodeficiency; selective IgA, IgM, and IgG subclass deficiencies; AIDS; lymphoma; plasma cell myeloma; leukemia), (3) alpha-1-antitrypsin deficiency, (4) primary ciliary dyskinesia, (5) rheumatic diseases (rheumatoid arthritis, Sjögren syndrome), and (6) localized airway obstruction (foreign body, tumor, mucoid impaction).
Symptoms of bronchiectasis include chronic cough with production of copious amounts of purulent sputum, hemoptysis, pleuritic chest pain, dyspnea, and weight loss. Physical findings may include crackles at the lung bases and wheezing.
B. Laboratory Findings and Imaging
Laboratory tests include immunoglobulin quantification; testing for cystic fibrosis; and sputum culture, including for nontuberculous mycobacteria. Obstructive pulmonary dysfunction with hypoxemia is seen in moderate or severe disease. Radiographic abnormalities include dilated and thickened bronchi that may appear as “tram tracks” or as ring-like markings (eFigure 9–5) (eFigure 9–6). Scattered irregular opacities, atelectasis, and focal consolidation may be present. High-resolution CT is the diagnostic study of choice.
Bronchiectasis. Diffuse cystic bronchiectasis resulting in lobar atelectasis of the right lower lobe in an elderly woman. Despite workup, the cause of this bronchiectasis remained unclear.
Bronchiectasis in cystic fibrosis. Chest radiograph of a patient with advanced cystic fibrosis demonstrating fibrotic changes with volume loss of the right lung as well as prominent bronchiectasis with a classic "tram track" appearance in the left upper lobe (arrows).
Haemophilus influenzae is the most common organism recovered from non–cystic fibrosis patients with bronchiectasis. P aeruginosa, Streptococcus pneumoniae, and Staphylococcus aureus are commonly identified. Nontuberculous mycobacteria are seen less commonly. Patients with Pseudomonas infection experience an accelerated course, with more frequent exacerbations and more rapid decline in lung function.
Treatment of acute exacerbations consists of antibiotics, daily chest physiotherapy with postural drainage and chest percussion, and inhaled bronchodilators. Handheld flutter valve devices may be as effective as chest physiotherapy in clearing secretions. Antibiotic therapy should be guided by sputum smears and prior cultures. If a specific bacterial pathogen cannot be isolated, then empiric oral antibiotic therapy for 10–14 ...