Cystic Fibrosis Flashcards
Parkinson’s is the commonest inherited genetic condition in the UK.
True or False?
False
Cystic Fibrosis
Cystic fibrosis is an ——– ——– condition.
Autosomal recessive
How many people are carriers
1 in 25
1 in 2500 births
97% of cystic fibrosis occurs in the
Caucasian population
How many individuals with CF in the UK?
9000 individuals (approx)
Cystic fibrosis is
the mutation of a gene located on chromosom 7q31, which codes for a protein called cystic fibrosis transmembrane regulator (CFTR)
What is the commonest mutation of CF?
Delta F5-8
Diagram inheritance of CF
CFTR protein
- CF occurs due to a mutation in a gene on the long arm of chromosome 7
- results in defect in the cystic fibrosis transmembrane conductance regulator protein
- CFTR sits in the membrane of epithelial cells and regulates the transport of Cl- through activation of cyclic AMP and through calcium activated chloride channels
- CFTR inhibits transport of sodium through the sodium channels in the epithelial cell membrane and regulates the movement of bicarbonate ions
process of CFTR
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Impact of abnormal CFTR:
- abnormal CFTR protein leads to decreased chloride reabsorption and increased sodium reabsorption
- secretions have high viscosity and reduced water content
- this impedes mucociliary clearance in the bronchi so respiratory secretions are stagnant
- decreased defence from respiratory infections
consequenc of recurring infections in the lungs
bronchiectasis
- recurring infections causes constant inflammation in the lungs, terminal and respiratory bronchioles not major airways
- causes destruction and dilation of the distal airways with mucous impaction, which predisposes to more infection which predisposes to worsening of the inflammation
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bronchiectasis
Common organs affected by CF?
- Respiratory System:
- bronchiectasis
- recurrent respiratory infections
- respiratory infections
- Gastrointestinal System:
- pancreatic insufficiency
- diabetic mellitus
- Skin:
- increased sweat, when exercising can lose a lot of sodium
- Reproductive system:
- infertile