Cystic fibrosis — CFTR channelopathy

Cystic fibrosis (CF) is autosomal recessive CFTR mutation → defective chloride transport → thick dehydrated secretions in lungs, pancreas, bile ducts, reproductive tract.

~11,000 UK CF population — life expectancy rising sharply with modulators

Organ involvement

Lungs:

  • Mucus plugging
  • Chronic infection — Staph aureus → Pseudomonas → Burkholderia
  • Bronchiectasis
  • Haemoptysis
  • Pneumothorax

Pancreas:

  • 90% exocrine insufficiency
  • CF-related diabetes — ~50% by age 30

Other:

  • Liver cirrhosis — focal biliary cirrhosis
  • Distal intestinal obstruction syndrome (DIOS)
  • Male infertility — congenital bilateral absence of vas deferens

Newborn screening pathway

IRT on blood spot → repeat IRT or sweat test → genetics → CF centre within days

Early Creon + physio — nutrition trajectory set in first year

Daily management

Airway clearance:

  • PEP devices, autogenic drainage, percussion
  • Exercise as adjunct

Inhaled therapies:

  • 7% hypertonic saline
  • Dornase alfa (Pulmozyme)
  • Bronchodilator before others

Antibiotics:

  • Acute exacerbation — IV 14 days
  • Chronic Pseudomonas — inhaled colistin/tobramycin, oral azithromycin

Nutrition:

  • Creon dosing — adjust to fat intake
  • Fat-soluble vitamin supplements

CFTR modulators

Kaftrio (elexacaftor/tezacaftor/ivacaftor):

  • Eligible ~90% UK mutation profile
  • FEV1 improvement, fewer IV antibiotics, weight gain

Access via NHS — specialist prescribing

Transition to adult care

Dedicated adult CF centres

Mental health, employment, insurance

Transplant referral when FEV1 <30% or rapid decline

CF is chronic intensive self-care — specialist team + modulators make adulthood and parenthood realistic for most born today.

Common questions about cystic fibrosis

What are the symptoms of cystic fibrosis?
Babies — meconium ileus, failure to thrive. Children — persistent cough, wheeze, recurrent chest infections, bulky foul stools, poor growth. Adults — bronchiectasis, sinus disease, diabetes (CF-related diabetes), liver disease, infertility (men — absent vas deferens). Salty skin — classic clue.
How is cystic fibrosis diagnosed?
Newborn blood spot immunoreactive trypsinogen (IRT) raised — sweat chloride test over 60 mmol/L confirms. Genetic testing identifies CFTR mutations — guides modulator eligibility. Some variants cause mild or single-organ disease — pancreatitis-only presentations in adults.
What is daily treatment for cystic fibrosis?
Airway clearance physiotherapy twice daily minimum. Hypertonic saline or dornase alfa nebulised. Inhaled antibiotics for chronic Pseudomonas. Creon with all meals and snacks if pancreatic insufficient. High-calorie diet — 120–150% normal intake. Exercise encouraged. Annual flu vaccine, never smoke.
What are CFTR modulators?
Drugs correcting CFTR protein function — Kaftrio (Trikafta) for F508del and many other mutations — improves lung function, reduces exacerbations, helps weight gain. Ivacaftor alone for gating mutations. Not curative but transformative — lung transplant still needed for some advanced disease.
Can people with cystic fibrosis have children?
Yes — with planning. Most men have obstructive azoospermia — fertility via surgical sperm retrieval and IVF. Women often fertile but high-risk pregnancy — specialist obstetric care. Pre-implantation genetic diagnosis available for carrier couples.

Sources