Productive Cough

Clinical Vignette

A 60-year-old woman presents with a persistent productive cough and has been troubled by recurrent chest infections. Please examine her respiratory system.

Positive Findings

  • General: Sputum pot present with thick, dark-green sputum, mild dyspnoea, clubbing of fingers, and possible cachexia.
  • Chest: Bilateral coarse inspiratory crackles that may clear with coughing, occasional wheeze, and signs of sputum retention (wet cough).
  • Peripheral signs: Clubbing of fingers, no evidence of situs inversus or significant scarring from previous surgeries.

Relevant Negative Findings

  • No evidence of cachexia or cor pulmonale (e.g. no raised JVP or peripheral oedema).
  • No signs of cyanosis or asterixis.
  • No signs of chronic obstructive pulmonary disease (COPD) or other comorbid conditions like diabetes.

What is the most likely diagnosis?

Bronchiectasis, likely secondary to post-infective causes given the patient's history of recurrent chest infections.

What is your differential diagnosis?

  • Cystic Fibrosis – Common in younger patients; requires sweat chloride test and genetic analysis.
  • Allergic Bronchopulmonary Aspergillosis (ABPA) – Consider if associated with asthma; IgE testing for Aspergillus may be indicated.
  • Chronic Obstructive Pulmonary Disease (COPD) – Possible in patients with smoking history; less likely if productive cough is persistent since childhood.
  • Primary Ciliary Dyskinesia – Consider if situs inversus or history of recurrent sinusitis/ear infections is present.
  • Immune Deficiency – Primary or secondary immunodeficiency can predispose to recurrent infections; check immunoglobulin levels.

How would you investigate this patient?

  • Diagnosis and Assessment:
    • Chest X-ray (CXR): May show tramline or ring shadows due to dilated and thickened bronchi.
    • High-resolution CT (HRCT): Confirms bronchial wall dilatation, shows classic "signet ring" appearance and lack of bronchial tapering.
    • Sputum culture: Assess for pathogens, especially Pseudomonas aeruginosa; send for routine, atypical, and fungal cultures.
  • Further Testing for Underlying Causes:
    • Serum immunoglobulins (IgG, IgA, IgM) to rule out immunodeficiency.
    • Aspergillus serology: Total IgE and specific IgE to Aspergillus for ABPA.
    • Sweat chloride test and CFTR genetic mutation analysis for cystic fibrosis.
    • Ciliary function tests (e.g., saccharin test) if primary ciliary dyskinesia is suspected.
  • Functional Assessment:
    • Spirometry: Typically shows an obstructive pattern (FEV1/FVC ratio < 0.7).
    • Bronchoscopy: May be needed to exclude mechanical obstruction if symptoms are unilateral or if there is suspicion of a foreign body or tumour.

How would you manage this patient?

  • General Support:
    • Specialist physiotherapy: Daily airway clearance techniques, such as active cycle breathing or postural drainage.
    • Regular monitoring and vaccinations: Pneumococcal and annual influenza vaccines.
  • Pharmacological Treatment:
    • Antibiotics:
      • Treat acute exacerbations, often requiring prolonged courses of antibiotics, including antipseudomonal agents like piperacillin or ceftazidime.
      • Consider long-term antibiotics, such as nebulised colistin or low-dose oral macrolides, for patients with frequent exacerbations.
    • Bronchodilators: If there is evidence of airflow limitation.
    • Mucolytics: Use carbocisteine to help reduce sputum viscosity.
  • Surgical Interventions:
    • Bronchial artery embolisation for massive haemoptysis.
    • Surgical resection: Rarely indicated, but may be considered in patients with localised disease that is refractory to medical therapy.
  • Monitoring for Complications:
    • Cor pulmonale: Look for signs such as raised JVP, RV heave, and peripheral oedema.
    • Secondary amyloidosis: Check for proteinuria and assess renal function.

Viva Questions

  • What is bronchiectasis?
    • Abnormal, permanent dilatation of bronchi associated with chronic infection and inflammation, leading to thickened bronchial walls, sputum production, and recurrent infections.
  • What are the main causes of bronchiectasis?
    • Postinfective (e.g., TB, severe pneumonia), cystic fibrosis, primary ciliary dyskinesia, immunodeficiency, and allergic bronchopulmonary aspergillosis (ABPA).
  • What are the differential diagnoses for bilateral coarse crackles?
    • Bronchiectasis (coarse inspiratory crackles), pulmonary fibrosis (fine, late inspiratory crackles), and pulmonary oedema (fine or coarse bibasal crackles with fluid overload).
  • How is bronchiectasis diagnosed radiologically?
    • HRCT is the gold standard, showing dilated bronchi (larger than accompanying artery), bronchial wall thickening, and mucus plugging ("signet ring" sign).
  • What pathogens are commonly found in bronchiectasis?
    • Common pathogens include Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae, Staphylococcus aureus, and non-tuberculosis mycobacteria.
  • What are some complications of bronchiectasis?
    • Cor pulmonale, massive haemoptysis, recurrent infections, empyema, secondary amyloidosis, and metastatic infections like cerebral abscess.
  • When should cystic fibrosis testing be considered in adults with bronchiectasis?
    • In those under 40 or with no other identifiable cause, persistent Staphylococcus aureus colonisation, upper lobe disease, malabsorption symptoms, or history of childhood steatorrhoea.