cystic fibrosis

Question 1

how many pts in the uk with CF?

Answer 1

10,837

Question 2

life expectancy of CF

Answer 2

50.6 years

Question 3

what is the pathophysio of CF?

Answer 3

defects in the gene for the cystic fibrosis transmembrane regulator (CFTR)

Question 4

what is the most common mutation in CF?

Answer 4

delta F508

Question 5

what is the function of the CFTR protein?

Answer 5

control chloride transport across epithelial membranes such as mucous, sweat, saliva, tears, and digestive enzymes
causes dehydration of mucous

Question 6

what is the main problem in CF?

Answer 6

thicker, viscous produced mucous

Question 7

what type of inheritance pattern is CF?

Answer 7

autosomal recessive condition
- both parents must pass on a faulty CFTR gene
- 25% chance that the child is born with two normal genes
- 50% chance that the child is born with one normal and one abnormal (carrier)
- 25% chance that the child is born with two abnormal genes.

Question 8

what are the 9 conditions newborns are screened for?

Answer 8

cystic fibrosis
sickle cell
congenital hypothyroidism
phenylketonuria (PKU)
medium-chain acyl-CoA dehydrogenase deficiency (MCADD)
maple syrup urine disease (MSUD)
isovaleric acidaemia (IVA)
glutaric acuduria type I (GAI)
homocystinuria (pyridoxine unresponsive) (HCU)

Question 9

when are newborns screened for congenital conditions?

Answer 9

5 days after birth
4 drops

Question 10

what is the diagnostic test for CF?

Answer 10

sweat test
- +ve screening test
- CF kids are salty
- pilocarpine and current
- collect sweat
- measure chloride content
- can be confirmed with gene testing

Question 11

what are the symptoms of CF in a baby?

Answer 11

meconium ileum = erogenic bowel - appears bright white on scan.

failure to thrive = due to bowel issues; cannot get nutrients from food

sinusitis

recurrent LRTIs

greasy/bulky stools = due to lack of getting rid of fats

prolapse

Question 12

what is bronchiectasis?

Answer 12

a long-term condition where the airways of the lungs become widened, leading to a build-up of excess mucus that can make the lungs more vulnerable to infection.

Question 13

why are pts with CF more prone to infection?

Answer 13

due to clogging of thick mucous in the airways which can cause collection of bacteria.
bronchiectasis

Question 14

common causes of infection in CF (bacteria, fungi etc)

Answer 14

pseudomonas
aspergillus fumigateurs - allergic bronchopulmonary aspergillosis leads to scarring and bronchiectasis

when there is infection, this can progress to colonisation.

Question 15

what is the treatment for CF?

Answer 15

antibiotics - inhaled, oral and IV
pulmonary rehab - physio, airway clearance techniques
pneumatic vest which puts pressure on chest wall to clear gunk (however little evidence)
DNAse which is an inhaled medicine which helps to break down the fragments in the mucous so it’s less thick
transplant - heart and lung

Question 16

what are the gastrointestinal effects of CF?

Answer 16

gastro-oesophageal reflux disease caused by coughing which increases thoracic pressure and causes stomach contents to come back up

pancreatic blockage - exocrine dysfunction
- inability to gain weight due to poor absorption, malnourishment, bulky stools and fat soluble vitamin deficiency.

can progress to “diabetes lite” - produce insulin but not enough and can cause pancreatic endocrine problems

Question 17

what is the treatment for the gastrointestinal effect?

Answer 17

dietician input

high calorie diet

creon! - amylase, lipase and protease -> taken with food to help breakdown food

ADEK vitamins -> fat soluble

Question 18

why does CF cause infertility?

Answer 18

effects 97% of men due to the absence of the vas deferent (not developed in the testes) so they are infertile but not sterile as they are able to produce but not transport

women are also effected - thick cervical mucous and low BMI which affects the menstrual cycle and unable to gain weight.

Question 19

what is kalydeco?

Answer 19

ivacaftor
acts on a specific protein that is only present in 5% of CF pts
costs a lot

Question 20

what is kaftrio?

Answer 20

ivacaftor, tezacaftor and elexacaftor
works on CFTR gene and makes the protein more common
works on the deltaF508 mutation
less expensive than kalydeco

Question 21

can CF patients socialise together?

Answer 21

NO

Question 22

what is the most common AR inherited condition in the UK?

Answer 22

haemochromatosis

Question 23

how does CF affect mucous?

Answer 23

reduced chloride outside cell = reduced water outside of cell = dehydrated sticky mucous

Question 24

why do people with CF require ADEK supplements?

Answer 24

fat malabsorption, ADEK are fat soluble

Question 25

How does pilocarpine work?

Answer 25

muscarinic cholinergic agonist