Bronchiectasis

Bronchiectasis is an irreversible and abnormal dilation in the bronchial tree that is generally caused by cycles of bronchial inflammation in addition to mucous plugging and progressive airway destruction. Although the widespread use of antibiotics has made bronchiectasis rare, conditions such as cystic fibrosis (CF), severe or protracted pneumonia, immunodeficiency, and COPD continue to cause it. The most important clinical finding is a chronic cough with copious mucopurulent sputum. Other symptoms may include dyspnea, rhinosinusitis, and hemoptysis. Physical examination reveals crackles and rhonchi on auscultation, often accompanied by wheezing. High-resolution computer tomography is the best diagnostic test and shows thickened bronchial walls, a signet-ring appearance, and “tram track” lines. Treatment focuses on alleviating symptoms and preventing exacerbations, and includes pulmonary physiotherapy and antibiotics to treat underlying infections. In rare cases, massive hemoptysis may complicate bronchiectasis and necessitate surgery or pulmonary artery embolization.

Bronchiectasis requires the combination of two important processes taking place in the bronchi: local infection or inflammation and either inadequate clearance of secretions, airway obstruction, or impaired host defenses.

• Pulmonary infections; (i.e., bacterial, viral, fungal), especially severe or chronic infections
• Disorders of secretion clearance or mucous plugging
  • Cystic fibrosis (CF)
  • Primary ciliary dyskinesia (PCD)
  • Allergic bronchopulmonary aspergillosis (ABPA)
• Bronchial narrowing or other forms of obstruction
  • COPD
  • Aspiration
  • Tumors
  • α1-antitrypsin deficiency
  • Other congenital and acquired conditions (e.g., congenital bronchiectasis, tracheomalacia, bronchogenic cyst)
• Immunodeficiency; (e.g., common variable immunodeficiency, hypogammaglobulinemia, HIV)
• Chronic inflammatory diseases (e.g., rheumatoid arthritis, Sjögren syndrome, Crohn's disease)

References:^{[1][2][3][4][5][6]}

• Chronic productive cough (lasting months to years) with copious mucopurulent sputum ; the following may be heard on auscultation:
  • Crackles and rhonchi
  • Wheezing (due to obstruction from secretions, airway collapsibility, or a concomitant condition)
  • Bronchophony
• Rhinosinusitis
• Dyspnea
• Hemoptysis: usually mild/self-limiting but severe hemorrhage that requires embolization may occur.
• Nonspecific symptoms (i.e., fatigue, weight loss, pallor due to anemia)
• Clubbing of nails (uncommon)
• Exacerbations of bronchiectasis
  • Increased production of mucous above baseline
  • Low-grade fever

Bronchiectasis should be suspected in a patient with chronic cough producing large amounts of sputum!
References:^[1][3][5]

• Imaging
  • Chest x-ray (best initial test)
    • Inflammation and fibrosis of bronchial walls lead to the appearance of parallel “tram track” lines
    • Thin-walled cysts (i.e., dilated bronchi forming sacs), possibly with air-fluid levels
    • Late-stage bronchiectasis: honeycombing
  • High-resolution computer tomography (HRCT): confirmatory test
    • Dilated bronchi with thickened walls; possible signet-ring appearance; and tram track lines
    • Cysts, especially at bronchial ends in lower lobes, and honeycombing
• Other tests
  • Sputum culture and smear: to determine infectious etiology (i.e. bacteria, mycobacteria, and fungi)
  • Blood tests
    • CBC with differential: may show anemia of chronic disease and ↑ WBCs, ↑ neutrophils
    • HIV testing, genetic testing for CF, immunoglobulin quantitation to determine other possible etiologies
  • Pulmonary function tests: findings consistent with obstructive pulmonary disease (i.e. ↓ FEV₁/FVC ratio)
  • Bronchoscopy: to visualize tumors, foreign bodies, or other lesions; may also be used in combination with bronchoalveolar lavage (BAL) to obtain specimens for staining and culture

Bronchiectasis cannot be ruled out with a chest x-ray!
References:^{[1][3][4][7][8][5]}

• Recurrent bronchopulmonary infections → obstructive ventilation disorder → respiratory failure and cor pulmonale
• Pulmonary hemorrhage; (massive hemoptysis)
• Pleural empyema
• Lung abscess

References:^[5]

We list the most important complications. The selection is not exhaustive.