Cystic fibrosis

Question 1

Cystic fibrosis
-pathophysiology
-presentation

Answer 1

AR => increased viscosity of secretions

Neonatal - meconium ileus (too sticky to pass through)
Recurrent chest infections
Malabsorption, steatorrhea, failure to thrive => short stature, bulky stools, rectal prolapse

Increased risk of DM

Sweat test - abnormally high chloride (60mEq/l+)

Question 2

Causes of
-false positive sweat tests
-false negative sweat tests

Answer 2

Malnutrition
Adrenal insufficiency
Glycogen storage diseases
Nephrogenic diabetes insipidus
Hypothyroidism, hypoparathyroidism
G6PD
Ectodermal dysplasia

Skin edema (hypoalbuminemia, hypoproteinemia)

Question 3

Cystic fibrosis
-management
-Paeruginosa infection

Answer 3

Regular (2x) chest physio and postural drainage

High calorie (high fat diet)
Vitamins, pancreatic enzyme supplements

Minimise contact with other CF patients
-prevent cross infection of P aeruginosa, Burkholderia cepacia

Lung transplantation
-not possible if infected with burkholderia cepacia due to increased mortality

If homozygous for delta F508 mutation - lumacaftor/ivacaftor

Paeruginosa infection => PO ciprofloxacin