Cystic fibrosis

Question 1

What is CF?

Answer 1

Autosomal recessive condition affecting mucous glands.

Caused by genetic mutation of CFTR gene on chromosome 7

Question 2

Consequences of this mutation in CF

Answer 2

Thick pancreatic/biliary secretions causing blockage of the ducts and resulting in lack of digestive enzymes e.g. lipase

Thick airway secretions - reduce airway clearance - susceptibility to airway infections

Congenital absence of vas deferens in males resulting in male infertility

Question 3

How does CF present?

Answer 3

Chronic cough
Recurrent RTIs
Steatorrhoea
Abdominal pain/ bloating
Failure to thrive

Nasal polyps
Finger clubbing

Question 4

How is CF diagnosed?

Answer 4

Screened for in newborn blood spot testing (5-9 days)

Sweat test is the gold standard

Genetic testing can also be performed - during pregnancy or after birth

Question 5

What is the sweat test?

Answer 5

Pilocarpine applied to the skin with a patch

Electrodes placed either side of the patch and small current passed between them - causing skin to sweat

Sweat is collected and sent for testing in the lab for chloride levels

Diagnostic chloride is >60mmol/L

Question 6

What bacteria can colonise airways in CF? Which one are we worried about?

Answer 6

Staph aureus
Haemophilus influenza
Klebsiella pneumoniae
E-coli

Pseudomonas Aeruginosa - worrying - difficult to get rid of as can become resistant to multiple antibiotics and leads to significant increase in morbidity/mortality
- Can be treated with long-term nebulised antibiotics e.g. tobramycin

Question 7

Management of CF

Answer 7

MDT - dietician, respiratory, physio, gastro

Chest:

• Chest physiotherapy - to help clear mucus
• Treat chest infections as they occur - may need prophylactic antibiotics
• Exercise - to improve respiratory function and clear sputum
• Bronchodilators may help reduce bronchoconstriction

Gastro/nutrition

• CREON tablets to digest fats in patients with pancreatic insufficiency
• High calorie diet

Avoid other CF patients

Regular follow-up appointments

Question 8

Complications of CF

Answer 8

Meconium ileus, prolonged neonatal jaundice

Recurrent RTIs
Failure to thrive

Reduced life expectancy - though this is improving
Pancreatic insufficiency
Diabetes
Liver disease
Infertility (in males