Cystic Fibrosis

Question 1

What is the gene that is mutated in CF?

Answer 1

CFTR (cystic fibrosis transmembrae conductance regulator gene)

Question 2

What is the incidence of CF in the general population?

Answer 2

1 in 2500

Question 3

Mode of inheritance of cystic fibrosis and what is the chromosome affected?

Answer 3

Autosomal recessive

Chromosome 7

Question 4

What is the neonatal presentation of cystic fibrosis?

Answer 4

Meconium ileus
Intestinal atresia
Hepatitis/Prolonged jaundice

Question 5

What is the infant presentation of cystic fibrosis?

Answer 5

Rectal prolapse
Failure to thrive
Malabsorption (Vitamins ADEK)

Question 6

What is the older children presentation of cystic fibrosis?

Answer 6

Recurrent chest infections
Malabsorption - steatorrhoea
Difficult asthma
Bronchiectasis
Haemoptysis
Nasal polyps
Liver disease
Diabetes Mellitus
Distal Intestinal Obstruction Syndrome
Clubbing

Question 7

Definitive test for cystic fibrosis?

Answer 7

Sweat test (look for elevated sodium and chloride)
Genetic testing

Question 8

Newborn screening test for cystic fibrosis?

Answer 8

Trypsinogen reactive test (done on day 5 after birth)

Question 9

Members of the MDT who look after CF patients?

Answer 9

Consultant respiratory paediatrician
Physiotherapist 
Pharmacist
General practitioner
Social worker

Question 10

What prophylactic medication for CF infections?

Answer 10

Oral flucloxacillin for Staph aureus until 3 years of age. Consider until 6 years

Question 11

Drugs to give in CF?

Answer 11

dornase alfa (mucolytic agent) / hypertonic saline
Immunomodulators i.e Azathioprine

GI problems:

1) Pancreatic enzyme replacement i.e Pancreatin
2) Vitamin ADEK supplements
3) Ursodeoxycholic acid (helps absorption of fat)