Bronchiectasis
Bronchiectasis is chronic, irreversible bronchial dilation from a cycle of infection, inflammation, and airway destruction, diagnosed by high-resolution CT and managed with airway clearance, treatment of the underlying cause, and antibiotics for exacerbations.
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What this article covers
- Overview
Chronic suppurative airway disease: bronchiectasis is permanent, irreversible dilation of the bronchi from destruction of airway architecture, driven by a self-perpetuating cycle of infection, inflammation, and mucus stasis.
- Epidemiology
Underrecognized without a smoking history: consider bronchiectasis in any patient with chronic cough, especially with frequent respiratory infections, even absent significant smoking exposure.
- Risk factors
Cystic fibrosis: abnormal CFTR-mediated mucociliary clearance drives chronic bacterial colonization and progressive bronchiectasis (see cystic fibrosis).
- Pathophysiology
The cycle begins with an inciting airway injury (infection, aspiration, or an inherited mucociliary/immune defect) that triggers prolonged airway inflammation.
- Clinical features
Chronic daily productive cough is the defining feature, present for months to years, with copious purulent (yellow-green) sputum that in some patients can be measured by the cupful, often worst in the mornings.
- Differential diagnosis
Chronic bronchitis/COPD: productive cough for more than 3 months per year for 2 consecutive years is a clinical diagnosis; distinguished from bronchiectasis by the absence of the characteristic…
- Diagnosis
Bronchiectasis is diagnosed by high-resolution chest CT, the most accurate test: the defining criteria are an airway (bronchial) internal diameter greater than its accompanying pulmonary artery, and…
- Management
First, identify and treat any underlying cause when one is found: this is unlikely to reverse existing symptoms from already-irreversible airway dilation but can prevent further progression (for…
- Complications
Massive hemoptysis from hypertrophied, friable bronchial artery collaterals is the most immediately life-threatening complication and can require emergent bronchial artery embolization.
- Prognosis
Existing airway dilation is irreversible: treating an identified underlying cause typically does not reverse current symptoms, though it can slow or prevent further progression.
- Prevention
Vaccinate against preventable respiratory pathogens: annual influenza vaccination and age-based pneumococcal vaccination reduce triggering respiratory infections.
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