Cystic Fibrosis Flashcards
What is the most common lethal genetic disorder?
Cystic Fibrosis
What number are carriers of CF in western populations?
1 in 25
What are the most common causes of morbidity in CF?
Lung dysfunction
Infection
Is CF autosomal recessive or dominant?
Recessive
The disease severity of CF is related to what?
Mutation
What are the 3 forms of CF screening?
Immunoreactive trypsinogen (IRT)-Guthrie Test.
Genetic screening.
Sweat test
What Cl- level indiates CF?
Abov 60mM
What Cl- level makes CF unlikely?
Below mM
What structural changes occur in CF?
Bronchial wall thickening
Bronchiectasis
Pneumothorax
What causes the decline in lung function in CF?
Massive neutrophil infiltration-Frustrated phagocytosis-Failure to clear bac and dying neuts- Inflammatory damage to airway tissue
What transfers Cl- out?
CFTR
What makes mucus difficult to clear in CF?
Low volume which leads to sticky viscous mucus
What does viscous mucus provide?
Growth environment for bacteria
How can we partially correct viscous mucus in CF?
Hypertonic saline
What organisms cause lung infections in CF?
Pseudomonas aeruginosa
Staph aureus
Haemophilus influenza
Burkholderia cepacia
Why are lung infections difficult to treat in CF?
Biofilms grow
What prophylactic antibiotics are given to infants with CF for s.aureus?
Fluoxacillin
What can be inhaled in CF to prevent pathogens?
Antibiotics- Tobramycin
What are B-agonists used for in CF?
Activation of residual CFTR activity
What osmotic agents are used in CF?
Hypertonic saline
Mannitol
Why is Recombinant DNAse used in CF?
Breaks down viscous mucus (contains large amounts of DNA)
Which defect is most common in CFTR in western europeans?
ΔF508
What does ataluren target?
Class I (G542X) protein synthesis. Forces read through of premature termination codon.
What does Lumacaftor target?
Class II chanel processing (ΔF508 )
What does Ivacaftor target?
Class III channel regulation (G551D)
What does emiloride do?
Blockes sodium resorption by blocking ENaC
