Bronchiectasis

Question 1

What is the pathophysiology behind bronchiectasis?

Answer 1

• Persistent dilation (ectasis) of bronchi due to damage from infection and inflammation.
  
  • The inflamed, thick-walled, collapsible airways reduce the flow of air and mucous, causing airway obstruction and creating a stagnant pool for recurrent infections to develop.
  • Pathological sub-types are cylindrical (large bronchi and mucus plugging), varicose (alternating dilation and constriction), and cystic (aka saccular). The latter is more severe and linked to CF.

Question 2

What are the possible causes for bronchiectasis?

Answer 2

• Infection: frequent and/or severe childhood lung infections, allergic bronchopulmonary aspergillosis, TB.
  
  • Asthma
  • Immunodeficiency: HIV, immunoglobulin deficiency.
  • Congenital disease: CF, primary ciliary dyskinesia, α-1 antitrypsin deficiency.
  • Gastric aspiration.
  • Obstruction: foreign body, tumour, lymphadenopathy.
  • Autoimmune: RA, Sjogren’s, ankylosing spondylitis, SLE, IBD.

Question 3

How prevelant is bronchiectasis?

Answer 3

• 1/400 overall, 1/100 in those aged >70.

Question 4

What are the signs and symptoms of bronchiectasis?

Answer 4

• Can be episodic and/or chronic.
Symptoms:
  
  • Cough with voluminous green/yellow sputum, and sometimes specks of blood.
  • Haemoptysis, which in ‘dry’ bronchiectasis (usually TB) occurs in the absence of sputum.
  • SOB and pleuritic chest pain.
  • Systemic symptoms: fever, weight loss.
• Signs:
  
  • Coarse, early-inspiratory crackles.
  • Squeaks (high pitch), rhonchi (low pitch), and wheeze.
  • Clubbing

Question 5

Which investigations and monitoring should be carried out in bronchiectasis?

Answer 5

• Bloods:
  
  • FBC: ↑WBC in infection, ↑RBC if hypoxemic, ↑eosinophils in aspergillosis.
  • ↑CRP in infection.
• Imaging:
  
  • CXR is often abnormal but non-specific. Shows tram lines (reflecting the absence of normal bronchial tapering), and tubular opacities.
  • High-res CT is required for diagnosis. Shows bronchial dilatation ± wall thickening, mucus-plugged small airways, and fluid-filled cysts.
• Lung tests:
  
  • Lung function tests: ↓FEV1, ↓FEV1/FVC.
  • Sputum culture: Pseudomonas aeruginosa (25%), H. influenzae, Strep. pneumo, and Staph. aureus are common. Repeated Staph. aureus suggests underlying CF or aspergillosis.
  • Bronchoscopy is only used for suspected foreign body inhalation or obstruction.
• Investigate cause:
  
  • Serum α-1 antitrypsin.
  • CF sweat test.
  • Immunodeficiency: HIV test, immunoglobulin levels.
  • Rheumatoid factor.
  • Aspergillus IgE and skin prick testing.
  • Sputum pH or swallow study if chronic aspiration suspected. Often used in children.
  • Ciliary function should be tested if no other cause is found and/or there have been chronic problems since childhood. Check exhaled nasal nitric oxide (low in primary ciliary dyskinesia) and follow up with bronchial biopsy with electron microscopy if positive.
• Monitoring:
  
  • Pulmonary function testing at least annually.
  • Regular sputum MC+S to check changing sensitivities.
  • Repeat imaging not needed unless there is a clinical indication.

Question 6

How is bronchiectasis managed?

Answer 6

• General measures
  
  • Smoking cessation.
  • Flu and pneumococcal vaccines.
  • Pulmonary rehab.
• Specific treatment
Antibiotics
Therapeutic antibiotics:
  
  • Longer courses (≥14 days) and sometimes higher doses are needed than in patients without bronchiectasis.
  • MC+S of sputum should always be done.
  • Empirical options: amoxicillin is 1st line, or quinolone if colonized with Pseudomonas.
• Prophylactic antibiotics:
  
  • Offer to those with frequent exacerbations.
  • Can be nebulized in kids, or in adults colonized with Pseudomonas.
  • Azithromycin is often used, and it also has anti-inflammatory effects.
• Sputum clearance
  
  • Chest physio for sputum clearance e.g. 30 minutes, 3 times daily.
  • Postural drainage.
  • Nebulised hypertonic saline aids sputum clearance by increasing its hydration. Use bronchodilators before giving as it can cause chest tightness.
• Other medical options
  
  • Inhaled bronchodilators for those with reversibility (a minority). Options: salbutamol or ipratropium PRN, tiotropium regularly.
  • O2 therapy or non-invasive ventilation for those with respiratory failure.
  • BTS advises against steroids, mucolytics, and leukotriene receptor antagonists.
• Surgery
  
  • Resection of affected lobe or lung in refractory disease confined to specific area.
  • Lung transplant if FEV1 <30% predicted.

Question 7

Which complications are associated with bronchiectasis?

Answer 7

• Respiratory failure.
  
  • Pneumothorax
  • Lung abscesses and empyema.
  • Cor pulmonale.
  • Massive hemoptysis. Treat with bronchial artery embolisation.