Bronchiectasis

Note: Bronchiectasis is a chronic destructive airway disease causing irreversible airway dilatation due to abnormal inflammatory response. About half of cases are idiopathic. Morbidity remains substantial despite modern therapy. 🔬

📖 About

• Bronchiectasis = abnormal, permanent dilation of bronchi from chronic infection and inflammation.
• It leads to a self‑perpetuating “vicious cycle”: infection → inflammation → airway damage → impaired clearance → further infection. 🔁
• Main symptoms → chronic productive cough, daily mucopurulent or purulent sputum, recurrent chest infections, and ± haemoptysis.
• Associated comorbidities: sinusitis, rhinosinusitis, asthma, COPD, autoimmune diseases.
• Prevalence increasing with ageing populations and better imaging: ~1 in 1000 adults in the UK.

🧠 Pathophysiology

• Repeated cycles of infection and neutrophilic inflammation → destruction of smooth muscle and elastic elements of bronchial wall.
• Leads to loss of ciliary function, mucus stasis, bacterial colonisation (H. influenzae, Pseudomonas, Moraxella).
• Tissue injury amplifies inflammatory cytokines: IL‑8, TNF‑α, neutrophil elastase → further epithelial damage.
• Chronic bacterial biofilm formation complicates clearance and antibiotic penetration.
• Histology: ulcerated bronchial epithelium, granulation tissue, and fibrosis with squamous metaplasia.

🔬 Morphological Types

• Cylindrical (tubular): uniform smooth widening; walls thickened but contour preserved.
• Varicose: alternating dilatation and narrowing → irregular “beaded” contour.
• Saccular (cystic): balloon‑like sacs, most severe, mucus-filled, distorted architecture.
• Distribution clues:
  • Upper‑lobe predominant → Cystic Fibrosis, post‑TB.
  • Middle‑lobe/lingula → atypical mycobacteria.
  • Lower‑lobe → aspiration, immune deficiency, idiopathic.

⚡ Causes (Aetiology)

🩺 Clinical Features

• Chronic cough – daily, often productive with volumes > 10–30 mL sputum/day.
• Sputum characteristics: Mucoid (clear) → Mucopurulent (yellow) → Purulent (green) during exacerbations.
• Recurrent exacerbations with increasing sputum volume, change of colour, fever.
• Dyspnoea — mild exertional in early disease, severe in extensive destruction.
• Haemoptysis from bronchial‑artery hypertrophy, occasionally life‑threatening.
• Systemic manifestations: fatigue, malaise, weight loss.
• Exam: coarse inspiratory crackles (“Velcro rales”), rhonchi, wheeze, clubbing of fingers.
• Children — failure to thrive or recurrent “pneumonias” in the same lobe.

🔎 Investigations

💥 Exacerbations

• Definition: Worsening cough, sputum purulence/volume, dyspnoea ± systemic symptoms lasting ≥ 48 h requiring therapy change.
• Investigation: Full blood count, CRP, sputum culture before antibiotics.
• Empirical treatment:
  • Non‑Pseudomonas: Amoxicillin 500 mg TDS or doxycycline 200 mg day 1 then 100 mg OD × 14 days.
  • Pseudomonas colonised: Ciprofloxacin 500–750 mg BID × 14 days (specialist advice required).
• Hospitalisation if: hypoxia, inability to self‑manage, severe haemoptysis, or systemic toxicity.

💊 Chronic / Preventive Management

🦠 Common Pathogens

• Haemophilus influenzae — most frequent overall.
• Pseudomonas aeruginosa — chronic colonisation; induces biofilm, poorer lung function.
• Moraxella catarrhalis, Staphylococcus aureus, atypical or non‑tuberculous mycobacteria (MAC).
• Frequent co‑infection with Aspergillus or Candida species possible in advanced cases.

⚠️ Complications

• Recurrent infections → accelerating airway destruction.
• Chronic colonisation by Pseudomonas → progressive lung function loss.
• Massive haemoptysis due to hypertrophied bronchial arteries (arterial embolisation may be required).
• Respiratory failure with hypercapnia and hypoxia in advanced disease.
• Pulmonary hypertension and cor pulmonale (secondary right‑heart failure).
• Secondary amyloidosis (from chronic inflammation).

📉 Prognosis & Scoring

• Depends on pathology extent, frequency of exacerbations, and pathogens.
• FACED score (FEV₁, Age, Chronic Pseudomonas, Radiological Extent, Dyspnoea) and BSI score are validated prognostic tools.
• Pseudomonas isolation and > 3 exacerbations/year predict poor prognosis.
• Good airway clearance + vaccine uptake linked to improved survival.

👶 Paediatric Considerations

• Often secondary to post‑infective damage (measles, pertussis) or primary immunodeficiency/ciliary defects.
• Present with persistent wet cough > 8 weeks, failure to thrive or recurrent lobar collapse.
• HRCT scan needed after antibiotic therapy to avoid false positives during acute infection.
• Management mirrors adults but requires early aetiologic investigation + family education.

🧭 Emerging / Adjunct Therapies

• Inhaled mannitol and dry powder hyperosmolar agents as mucociliary enhancers.
• Macrolides for anti‑inflammatory properties under trial (e.g. azithromycin long term).
• Targeted anti‑elastase or anti‑IL‑8 therapies under development.
• Tele‑monitoring for sputum colour/volume and digital PEF tracking for self‑management plans.

📚 References

• British Thoracic Society Guideline for Bronchiectasis (2019)
• European Respiratory Journal – Bronchiectasis Management Consensus
• Respiratory Care Review – Bronchiectasis
• GOLD Guidelines for COPD Overlap

3 Clinical Cases — Bronchiectasis 🫁🔄

• Case 1 — Post‑infective Bronchiectasis 🦠: 34‑year‑old woman with daily purulent sputum since childhood measles pneumonia. HRCT: “signet‑ring” pattern. Teaching: Childhood necrotising infection → local bronchiectasis. Long‑term airway clearance and culture‑guided antibiotic maintenance essential.
• Case 2 — Cystic Fibrosis related 🧬: 22‑year‑old man with CF and recurrent Pseudomonas colonisation presents with worsening dyspnoea and purulent sputum. Teaching: CF is the prototype of diffuse upper‑lobe bronchiectasis; management requires daily physiotherapy, nebulised antibiotics and CFTR‑modulator therapy (e.g. ivacaftor).
• Case 3 — Immune Deficiency related 🛡️: 45‑year‑old man with CVID complains of recurrent sinopulmonary infections and haemoptysis. Investigations show low IgG; HRCT: bilateral cylindrical bronchiectasis. Teaching: Treat with monthly immunoglobulin replacement and infection prophylaxis; tailored physiotherapy reduces exacerbations.