Cystic Fibrosis

Question 1

Inheritance pattern

Answer 1

AR.

Question 2

Caused by?

Answer 2

Defect in ATP-binding cassette transporter gene on chromo 7 that encodes for CFTR protein.
Most common mutation is F508del

Question 3

CFTR

Answer 3

Epithelial chloride channel. Has signaling effects on other membrane channels.
Issues with it cause problems in salt/water movement across cell mems.. leading to abnormally thick secretions and critically altering host defnese in lung.

Question 4

Typical features of CF

Answer 4

• Greasy, bulky, foul-smelling stools
• Failure to thrive
• Recurrent respiratory and chronic sinus infections
• Digital clubbing
• Bronchiectasis (damged/expanded air ways)
• Sweat chloride > 60

Question 5

Clinically may see…

Answer 5

Tachypnea (breathing fast), retractions, nasal polyps, severe dehydration and so on

Question 6

Most common CF presentation

Answer 6

Failure to thrive. 85% have pancreatic insufficiency.

Question 7

Meconium ileus

Answer 7

15% of CF newborns. Severe intestinal obstruction. Basically baby poop is stuck.

Question 8

Respiratory presentation?

Answer 8

Productive cough, wheezing, chronic bronchitis, recurrent pneumonia, progressive obstructive airway disease, exercise intolerance, dyspnea (shortness of breath), hemoptysis (coughing blood)

Question 9

Treatment

Answer 9

Diet (enzymes, high calorie, salt supplement), airway clearance (percussiion, pulmozyme inhaled, inhaled saline, bronchodilators), antibiotic therapy (TOBI, inhaled), anti-inflammatory (ibuprofen), CFTR modulators

Question 10

CFTR modulators

Answer 10

Ivacaftor only for ppl with G551D mutation

Lumacaftor/ivacaftor combination: 12 years and older, 2 copies of F508del.

Question 11

Prognosis

Answer 11

Was early childhood, now 35 yeras. Rate of lung disease progression determines survival.