Cystic Fibrosis and the Gastrointestinal tract Flashcards
What is the cystic fibrosis transmembrane conductance regulator (CFTR)?
- a membrane protein and chloride channel
- encoded by the CFTR gene
- this is mutated in cystic fibrosis
What type of mutation, in terms of how affected genes are is cycstic fibrosis?
- point mutation
- a single nucleotide is affected
What is the most common genetic mutation in cycstic fibrosis?
- deltaF508
In cystic fibrosis are the mutations in the CFTR that patients have on their 2 different alleles homozygous or heterozygous?
- can be both
- homozygous (2 of the same gene)
- heterozygous (2 different genes) - RARER
In cystic fibrosis mutations in the CFTR affect the membrane proteins ability to pump chloride (Cl-). In the body this specifically affects something that is produced by epithelial cells, and therefore affects very specific tissues. What is it that is affected in cystic fibrosis?
- mucous]
- lungs, pancreas, GIT
In cystic fibrosis mutations in the CFTR affect the membrane proteins ability to pump chloride (Cl-). In the body this specifically affects mucous that is produced by epithelial cells, and therefore affects very specific tissues. How can this affected the GIT?
- affects bicarbonate and fluid levels in GIT
In cystic fibrosis mutations in the CFTR affect the membrane proteins ability to pump chloride (Cl-). In the body this specifically affects mucous that is produced by epithelial cells, and therefore affects very specific tissues. How can this affected the pancreas?
- exocrine and endocrine secretions are sticky
- leads to pabcreatic insufficiency
In cystic fibrosis mutations in the CFTR affect the membrane proteins ability to pump chloride (Cl-). In the body this specifically affects mucous that is produced by epithelial cells, and therefore affects very specific tissues. How can this affected failure to develop?
- canalisation, which is tube formation is impaired if mucous is affected
- the intestine in utero (causing neonatal meconium (dark stricky mucous) ileus)
- essentially blocking of GIT
Can cystic fibrosis present as acute or chronic only?
- both
Does cystic fibrosis present at any specific age?
- any age
- generally diagnosed early though
As the GIT and pancreas are affected, what can this lead to?
- malabsotpion of nutrients
If a patient presents at A&E with cystic fibrosis and acute abdomianl pain, what could be some other differential diagnosis that are associated with cystic fibrosis?
- pancreatitis (inflammation of pancreas)
- distal intestinal obstructive syndrome (DIOS)
- cholecystitis (gallbladder inflammation)
- gastro-oesophageal reflux disease (GORD)
- Cystic Fibrosis Liver Disease (CFLD)
- colorectal cancer
If a patient presents at A&E with cystic fibrosis and acute abdomianl pain, what could be some other differential diagnosis that are NOT associated with cystic fibrosis?
- IBS
- appendicitis
- gastritis
- gastroenteritis
How can cystic fibrosis be inherited?
- autosomal recessive (no sex chromosomes)
- patients need a mutated gene from both parents
- if only one gene they are a carrier
If a patient presents at A&E with cystic fibrosis and acute abdomianl pain, what could be some of the tests run that could help identify the problem?
- bloods
- chest X-ray
- abdominal CT scan
What is distal intestinal obstruction syndrome (DIOS)
- a complication of cystic fibrosis
- bowel becomes partially or completely blocked
- generallty occurs where the small bowel joins the large bowel.