Cystic Fibrosis

Question 1

What is the genetic basis of CF?

Answer 1

Mutation in CTFR gene on chromosome 7

• most commonly F508 deletion
• 1,500 know disease causing mutations

Question 2

What does CFTR do?

Answer 2

CF transmembrane conductance regulator protein epithelial Cl channel & affects other channels

mutation => salt and water movement difficulties
- abnormally thick secretions

Question 3

What is the incidence and prognosis of CF?

Answer 3

1:3000 caucasian
1:9000 hispanic
average lifespan of 37 yrs (may be up to 40)

Question 4

What are some of the common symptoms of CF?

Answer 4

recurrent respiratory infections
chronic sinus infections
nasal polyps
rectal prolapse
deficiency of fat soluble vitamins A D E K
Muconeum ilieus
Bronchiectasis (widening/scarring of airways)
Cl>60mmol/L in sweat
digital clubbing
greasy, bulky, malodorous stools/ FTT (pancreatic exocrine insufficiency)

Question 5

What is the effect of CF on the pancreas?

Answer 5

fails to produce any/ sufficeind digestive enzymes to break down and absorb fats and protein
>85% of CF patients

Question 6

What is a pulmonary exacerbation?

Answer 6

acute change in respiratory signs and symptoms from baseline:

• increased cough & sputum
• decreased exercise tolerence
• malaise
• anorexia
• new x ray or lung function findinge

TX: antibiotics, increased airway clearance, 1-2 weeks in hospital

Question 7

In what 3 ways is CF diagnosed?

Answer 7

meconium ileus (presumptive)
Cl sweat test
genotype

Question 8

How is CF treated?

Answer 8

Diet
- high fat, high protein, high calorie
Supplements
- pancreatic enzymes 
- fat soluble vitamins
- salt
PT
- percussive 
Rx
- inhaled mucolytic - recombinant DNAse - pulmozyme
- inhaled hypertonic saline
- bronchiodilators
- antibiotics(oral & IV): tobramycin (TOBI)
- Inhaled aztreonam (cayston)
- Anti inflamatory: Ibuprophin Azithromycin

Ivacaftor - G551D mutation