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General Medicine

Bronchiectasis

Permanent structural dilation of airways due to chronic inflammation and recurrent infections.

Source: WHO / CDC / NIH Evidence Guidelines
Updated: Aug 19, 2026
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Red Flag Warning & Emergency Situations

Emergency Management: Acute respiratory failure or massive hemoptysis requiring immediate ICU admission and embolization.

Core Definition:

Permanent, abnormal dilation and destruction of the major bronchi and bronchioles caused by chronic infection and inflammation.

Detailed Overview

Characterized by the vicious cycle of impaired mucociliary clearance, airway pooling of mucus, recurrent chronic bacterial infections, and intense neutrophilic inflammation. This destroys the elastin and muscular components of the bronchial wall. It typically presents with chronic daily cough with copious purulent sputum.

Epidemiology & Demographics

Prevalence is 350-500 per 100,000 in the US, rising steeply with age (>70 years). More common in women.

Etiological Mechanism

Post-infectious (severe pneumonia, TB), Cystic Fibrosis (CFTR mutations), Primary Ciliary Dyskinesia, and immunodeficiencies (CVID).

Primary Causes

Recurrent airway infections (Pseudomonas, H. influenzae, NTM) causing structural damage.

An initial insult impairs mucociliary clearance. Retained mucus allows bacterial colonization (vicious cycle hypothesis). Neutrophils release elastase and matrix metalloproteinases, which destroy the muscularis and elastic tissue of the bronchial wall, leading to permanent abnormal dilation.

Diagnostic Criteria & Guidelines

Diagnosed radiographically by High-Resolution CT (HRCT) showing airway dilation (bronchoarterial ratio >1) and lack of airway tapering.

First-Line Treatment:

Airway clearance therapy (chest physiotherapy, oscillatory PEP devices). Hypertonic saline (7%) nebulized BID. Treat acute exacerbations with oral Azithromycin 500 mg daily or Amoxicillin/Clavulanate 875/125 mg BID for 14 days.

Second-Line & Adjunctive Therapy

Inhaled antibiotics for chronic Pseudomonas colonization (e.g., Inhaled Tobramycin 300 mg BID alternating months). Chronic macrolide therapy (Azithromycin 250 mg 3x/week) for anti-inflammatory effects.

Surgical & Procedural Management

Bronchial artery embolization for massive hemoptysis. Surgical resection (lobectomy) for localized, severe disease failing medical therapy.

Patient Counseling & Advice

Emphasize that the structural lung damage is irreversible; daily mucus clearance is essential to prevent exacerbations.

Follow-Up & Monitoring Schedule

Annual spirometry (shows obstructive pattern, FEV1/FVC < 0.70) and semi-annual sputum cultures.

Preventive Strategies

Childhood vaccinations (pertussis, measles) and prompt treatment of pneumonia.

Progressive decline in lung function; FEV1 drops by 50-55 mL/year.

Authoritative Sources & Evidence References
World Health Organization (WHO) & CDC Guidelines: Information compiled from current international clinical practice guidelines.

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