6- cystic fibrosis

• Cystic Fibrosis

  Autosomal recessive life-limiting disease
• Cystic Fibrosis

  • Genetic mutation of CFTR on chromosome 7 (a chloride channel and regulatory protein found in epithelial cell membranes in the lungs, pancreas, GI & reproductive tract)
  • Abnormal ion transport across epithelial cells
  • Increased salt content in sweat gland secretions, alteration in viscosity, & tenacity of mucus
• Presentation of Cystic Fibrosis

  1. Decreased airway surface liquid layer

  2. Impaired ciliary function

  3. Retention of mucopurulent secretions

  4. Mucus stasis & airway inflammation

  5. Recurrent chest infections
• Recurrent chest infections in Cystic Fibrosis

  • Staph aureus (below 10 years of age)
  • Pseudomonas (after 10 years of age)
• Cystic Fibrosis

  • Damage to bronchial wall
  • Bronchiectasis
  • Abscess formation
• Cystic Fibrosis

  • Clubbing
  • Hyperinflated lung
  • Coarse inspiratory crackles
  • Expiratory wheeze
• Gastrointestinal complications in Cystic Fibrosis


  1. Small bowel obstruction

  2. Meconium ileus (children)

  3. Distal intestinal obstruction syndrome (adults)
• Cystic Fibrosis

  • Pancreatic exocrine insufficiency (lipase, amylase, protease)
  • Vitamin ADEK malabsorption
  • Steatorrhea
  • Failure to thrive in infancy
  • Low BMI
• Diagnosis of Cystic Fibrosis

  1. Sweat test

  2. Neonatal heel prick screening at birth (measure immunoreactive trypsinogens)

  3. Confirmatory genetic testing
• Treatment of Cystic Fibrosis

  1. Multidisciplinary team, follow-up every 3 months (record FEV1 & BMI)

  2. Airway clearance technique

  3. Long-term azithromycin (immunomodulatory, ↓ exacerbation frequency)

  4. Nebulized therapy (recombinant human DNase, hypertonic saline, inhaled mannitol, long-term antipseudomonal suppression therapy)

  5. Combination antibiotic therapy for Pseudomonas infections

  6. Increase caloric intake 150%

  7. Fat soluble vitamin replacement (ADEK)

  8. Overnight feeding via gastrotomy

  9. Pancreatic enzyme replacement therapy

  10. Vaccinations (influenza, pneumococcal)

  11. Oxygen and non-invasive ventilation for respiratory failure

  12. Lung transplant if FEV1 30% predicted

  13. CFTR modulating genetic therapy: Ivacaftor
• Respiratory complications of Cystic Fibrosis

  • Recurrent infections
  • Chronic daily cough and sputum
  • SOB
  • Hemoptysis (may be massive)
  • Recurrent sinusitis & Nasal polyps
  • Pneumothorax
  • Respiratory failure (95% die of respiratory failure)
  • Cor pulmonale
• Gastrointestinal complications of Cystic Fibrosis


  • Cirrhosis/portal HTN/hepatomegaly/abnormal LFTs (liver disease in 20%)
  • Distal intestinal obstruction syndrome
  • Increased risk of gastrointestinal malignancy
• Infertility in Cystic Fibrosis

  • Male: 95% azoospermia, 20% absence of vas deferens
  • Female: thick cervical mucus blocks sperm entry
• Other complications of Cystic Fibrosis

  • Diabetes mellitus (CF-related diabetes, in 40-50% of older adults)
  • Kidney stones (calcium stones)
  • Osteoporosis & arthropathy