Cystic Fibrosis

Question 1

Clinical signs of CF

Answer 1

Small stature, clubbed, tachypnoeic, purulent sputum
Hyperinflated with reduced expansion
Coarse crackles and wheeze (bronchiectasis)
Portex reservoir under skin or Hickman line/scars

Question 2

Genetics of CF

Answer 2

Incidence of 1/2500 live births
Autosomal recessive ch 7q
Gene encodes CFTR (chloride channel)
Commonest (70%) and most severe mutation is deletion of delta508

Question 3

Pathophysiology of CF

Answer 3

Thick secretions block lumens:
Bronchioles - bronchiectasis
Pancreatic ducts - loss of exocrine and endocrine functions
Gut - distal intestinal obstruction syndrome (DIOS)
Seminal vesicles - male infertility (+CAVD)
Fallopian tubes - female infertility

Question 4

Cystic fibrosis Ix

Answer 4

Screened for at birth (heelprick)
Sweat test Na>60mmol/L (false positive in hypothyroidism and addisons)
Genetic screening

Question 5

Cystic fibrosis tx

Answer 5

Postural drainage and active cycle breathing
Prompt antibiotics for infections
Pancrease(TM) and fat soluble vitamin preparations
Mucolytics (DNAse)
Immunisations
Double lung transplant (50% 5-year survival)
Gene therapy in development

Question 6

Prognosis of CF

Answer 6

Median survival 35y

Poor prognosis of infected with Burkholderia cepacia