Revision Flashcards
What mutation results in CF?
Mutation of the CFTR (membrane protein that transports Na and Cl across the membrane)
The most common mutation is (F508) associated with recurrent bronchopulmonary infections and pancreatic insufficiency.
What are the two main system affected by CF and what impact/symptoms do they have?
Pancreatic insufficiency:
- Failure to thrive
- Abnormal stool
Bronchopulmonary Infections
- Coughing
- SOB
- Malaise
What is the treatment for pancreatic insufficiency for patients with CF?
- enteric coated enzyme pellets
- H2 antagonist … or … proton pump inhibitor
- nasogastric feeding tube
What is the treatment for bronchopulmonary infections in patients with CF?? pre and post infection??
Pre infection:
- segregation/cohorting
- vaccinations
- mucolytics
- prophylactic antibiotics
Post infection:
- Two antibiotics (B-lactams + aminoglycoside)
- physiotherapy
- autogenic drainage
- lung transplant
State some investigations for CF?
Heel prick for increased immunoreactive trysionogen (guthrie test done at day 5)
Sweat test using pilocarpine iontophoresis
CXR for fibrosis
Spirometry should be obstructive
State some clinical features of young children with CF?
Failure to thrive
Short stature
Steatorrhoea
Frequent chest infections
name the mutation that causes CF which can be treated with ivacaftor
Celtic mutation (G551D)
What percentage of patients have the celtic mutation ?
5-10%
what membrane protein is affected during CF?
Cystic Fibrosis Transmembrane conductance Regulator (CFTR)
what happens when the CFTR is absent or abnormal during CF?
less Cl ions can be released into the lumen from the cell but Na is still leaving the lumen and being taken up by the cell which consequently pulls water into the cell which makes the contents of the lumen dehydrated and very sticky and thick which is difficult to move through the lumen
what type of mutation is F508?
autosomal recessive
what is the gene prevalence of CF?
1 in 25
what is the incidence of CF?
1 in 2500
what chromosome does the mutation occur on?
q arm of chromosome 7
what does the expensive drug ivacaftor do?
improves Cl movement into lumen
reduces Cl in sweat
what are the three functions of CFTR?
regulates liquid volume in the lumen by releasing Cl into the lumen
prevents cilia collapse
prevents excessive inflammation
Has screening babies at birth decreased mortality?
no
only improves lung function and nutrition
what are the numbers that the Cl should be under for CF to be/not to be diagnosed?
60 - CF diagnosis
Name the three main bacteria that cause recurrent bronchopulmonary infections
Staph. aureus
Haemophilus influenza
Pseudomonas aeruginosa
Out of the three main infective agents for bronchopulmonary infections, which is the only one that should be treated with IV antibiotics?
Pseudomonas aeruginosa
out of the three infective agents, which one are you more likely to get in later life ?
pseudomonas aeruginosa
where do people become infected with pseudomonas aeruginosa ?
shower heads, sinks
biofilm
what are the two complications of bronchopulomnary infections?
haemoptyisis
pneumothorax
name four other less common organisms which can cause a lung infection.
burkholderia cepacia
stenotropomonas maltophila
alcaligenes xylosoxidans
atypical mycobacteria e.g. M. abscessus
