CF Definition etc

• Incidence of CF:

  • CF is the most common life-limiting inherited disease in Caucasian populations
  • About 1 in 25 carries defective gene
  • About 1 in 2,500 live (Caucasian) births
  • Where both parents are carriers
  • 1:2 chance of producing a carrier
  • 1:4 chance of producing an affected baby
• Chromosome 7:

  • Defect is on chromosome 7
  • Mutation in the cystic fibrosis transmembrane regulator (CFTR) gene
  • CFTR acts as a chloride channel in airway epithelial cells
  • Decreased secretion of chloride and water by airway epithelial cells
  • Results in thick dehydrated intraluminal mucus
• Diagnosis of CF:

  • The sweat test is the diagnostic test for CF
  • Chloride concentrations in sweat is increased
  • Salty babies
  • Meconium ileus - when a babys first faeces is stickier and harder
• Genetic & screening tests of CF:

  • Carrier test
  • Pre natal genetic test
  • Post natal genetic test can confirm diagnosis
  • some cells are scraped from inside of cheek & tested to detect CF gene
  • Screening test
  • a 'heel prick' blood test taken a few days after birth
• Affected organs of CF:

  • Cystic fibrosis mainly affects the lungs and pancreas
  • Disorder of the exocrine glands
  • Can affect other parts of the body
  • reproductive organs
  • liver
  • nose and sinuses
  • sweat glands
• Survival:

  • CF first described in 1930s - 70% of diagnosed babies died within first few years of life
  • Survival is approaching 50 years for those born today with CF
• Common respiratory pathogens in CF:

  • Staphylococcus aureus
  • Pseudomonas aeruginosa (80-90% adults)
  • Burkholderia cepacia
• Cor pulmonale:

  • Cor pulmonale (aka right ventricular failure) develops
  • How and why do patients with chronic lung disease get RVF?
  • diffuse HPVC ->
  • pulmonary hypertension ->
  • increased pulmonary artery pressure ->
  • right ventricular failure
• Respiratory signs & symptoms:

  • Persistent productive cough
  • Haemoptysis – may be life-threatening
  • Pneumothorax (16-18% pts > 18yrs)
  • Wheeze
  • Recurring chest infections
  • Shortness of breath
  • Increased work of breathing
  • Decrease in exercise tolerance
  • Air trapping & hyperinflation – decreased lung compliance
• Stress Urinary Incontinence:

  • Under reported in cystic fibrosis
  • Caused by coughing
  • More common in females
  • Pelvic floor exercises can improve degree of leakage