Bronchiectasis is a chronic lung condition characterized by abnormal and irreversible widening (dilatation) of the bronchi, the large airways of the lungs. This structural damage leads to impaired clearance of mucus, resulting in persistent cough, frequent respiratory infections, and progressive decline in lung function. It is not a single disease but a final common pathway of multiple underlying causes that lead to chronic airway inflammation and destruction of the bronchial walls.
Causes and Risk Factors
Bronchiectasis can develop from various insults to the airways, but all share a cycle of infection, inflammation, airway damage, and impaired mucus clearance.
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Post-infectious causes
Severe or repeated lung infections (pneumonia, tuberculosis, whooping cough, measles, adenovirus, COVID-19, etc.) can cause permanent airway damage. -
Underlying medical conditions
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Cystic fibrosis (CF): The most common genetic cause, where thick mucus predisposes to infections.
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Primary ciliary dyskinesia: Rare inherited disorder where cilia cannot clear mucus effectively.
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Immunodeficiency disorders: e.g., hypogammaglobulinemia, HIV/AIDS, post-transplant immunosuppression.
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Autoimmune conditions: Rheumatoid arthritis, Sjögren’s syndrome, inflammatory bowel disease.
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Allergic bronchopulmonary aspergillosis (ABPA): Hypersensitivity to Aspergillus fungi damaging airways.
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Aspiration and obstruction: Inhalation of foreign bodies, tumors, or chronic aspiration due to reflux.
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Risk factors
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Childhood respiratory infections
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Chronic smoking
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Air pollution exposure
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Poor access to medical care or delayed treatment of infections
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Pathophysiology
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Initial insult damages bronchial walls.
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Impaired mucociliary clearance causes mucus accumulation.
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Bacterial colonization develops in stagnant mucus (commonly Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae).
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Persistent inflammation releases proteases, cytokines, and toxins, which further erode airway structure.
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Irreversible dilatation of bronchi occurs, creating pockets where mucus continues to pool.
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Vicious cycle: infection → inflammation → damage → more infection.
Symptoms
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Chronic productive cough with daily sputum, often thick, purulent, or foul-smelling.
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Recurrent chest infections requiring antibiotics.
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Wheezing and shortness of breath.
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Chest pain, particularly pleuritic pain during infections.
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Hemoptysis (coughing up blood).
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Fatigue, weight loss, and reduced exercise tolerance.
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In advanced disease: clubbing of the fingers, respiratory failure, or cor pulmonale.
Diagnosis
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History and examination: Persistent cough, recurrent infections, sputum characteristics, risk factor history.
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Imaging:
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High-resolution CT (HRCT) scan: Gold standard; shows airway dilatation (“signet ring sign”), thickened bronchial walls, mucus plugging.
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Chest X-ray: May show tram-track lines or ring shadows but less sensitive.
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Microbiology: Sputum cultures to detect bacterial colonization (e.g., Pseudomonas).
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Pulmonary function tests: Often show obstructive pattern (reduced FEV1/FVC).
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Blood tests: To investigate underlying immunodeficiency, autoimmune disease, or inflammation.
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Other tests:
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Sweat chloride test / genetic testing for cystic fibrosis.
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Aspergillus IgE/skin test for ABPA.
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Bronchoscopy in selected cases for obstruction or localization.
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Complications
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Repeated lower respiratory infections
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Respiratory failure (type II hypercapnia in advanced stages)
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Hemoptysis (can be massive, life-threatening)
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Pulmonary hypertension and cor pulmonale
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Reduced quality of life due to chronic symptoms
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Increased mortality in severe cases
Management
Management aims to reduce infections, improve mucus clearance, and slow disease progression. Treatment varies by severity, underlying cause, and presence of exacerbations.
1. Airway Clearance Techniques
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Chest physiotherapy / postural drainage: Positions that allow gravity to drain mucus.
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Active cycle of breathing techniques (ACBT).
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Oscillatory positive expiratory pressure (PEP) devices (e.g., Flutter, Acapella).
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Nebulized saline (0.9% or 3–7% hypertonic saline): Thins mucus for easier clearance.
2. Pharmacological Treatment
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Antibiotics
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Exacerbations:
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Amoxicillin 500 mg orally three times daily for 7–14 days.
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Doxycycline 100 mg once daily for 7–14 days.
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Clarithromycin 500 mg twice daily for 7–14 days.
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Ciprofloxacin 500–750 mg twice daily for 14 days (for Pseudomonas infections).
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Chronic suppressive therapy:
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Long-term macrolides (e.g., Azithromycin 250–500 mg three times weekly) to reduce exacerbations, with monitoring for QT prolongation and hearing issues.
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Inhaled antibiotics (e.g., nebulized Tobramycin 300 mg twice daily) in chronic Pseudomonas colonization, often used in cystic fibrosis bronchiectasis.
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Bronchodilators
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Inhaled Salbutamol (100–200 mcg via inhaler, as needed) can relieve breathlessness, especially in patients with airflow obstruction.
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Anti-inflammatory therapy
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Routine inhaled corticosteroids are not generally recommended, unless there is coexisting asthma or COPD.
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In ABPA, Prednisolone (30–40 mg daily, tapered) with antifungal therapy (Itraconazole 200 mg twice daily).
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Mucolytics
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Carbocisteine 750 mg three times daily (dose may be reduced to 750 mg twice daily after initial period) may reduce sputum viscosity in some patients.
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3. Vaccinations
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Influenza vaccine annually.
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Pneumococcal vaccine according to guidelines.
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COVID-19 vaccine to reduce viral triggers.
4. Surgery and Interventional Options
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Surgical resection (lobectomy or segmentectomy) in localized, severe disease not controlled by medical therapy.
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Bronchial artery embolization for life-threatening hemoptysis.
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Lung transplantation in end-stage disease (especially in cystic fibrosis).
5. Management of Underlying Cause
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Cystic fibrosis: specialized multidisciplinary care, CFTR modulators (e.g., Ivacaftor).
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Immunodeficiency: immunoglobulin replacement therapy.
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ABPA: corticosteroids and antifungals.
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Reflux/aspiration: lifestyle changes, Proton Pump Inhibitors (e.g., Omeprazole 20–40 mg daily).
Lifestyle and Supportive Measures
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Smoking cessation is crucial.
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Regular exercise improves lung capacity and mucus clearance.
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Adequate hydration to thin secretions.
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Pulmonary rehabilitation programs.
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Psychological support and patient education.
Prognosis
The outlook for bronchiectasis depends on severity, frequency of exacerbations, presence of Pseudomonas colonization, and comorbidities. With modern airway clearance techniques, antibiotics, and specialist care, many patients maintain a good quality of life. However, progressive decline is possible in severe cases, particularly when associated with cystic fibrosis or frequent infections.
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