CF

Question 1

What is the risk of having a child with CF if one parent is a carrier?

Answer 1

1/1000

Question 2

When is prenatal screening for CF performed?

Answer 2

When both parents are carriers (25%) or previous child has CF

Question 3

What are the main treatment goals of CF?

Answer 3

Control infections, maintain nutrition and prevent intestinal obstruction

Question 4

What are some intestinal problems seen in CF?

Answer 4

meconium illium - congenital onbstruction
distal intestinal obstruction
GI cancer susceptibility

Question 5

Describe the most common CFTR mutation seen in CF.

Answer 5

F508del - incorrectly folded protein, 70% of mutations, seen in 90% of CF cases

Question 6

In which CF mutations are pancreas deficiencies seen?

Answer 6

All the severe ones, F508del, G542X, G551D. All can cause exocrine deficiency and diabetes

Question 7

Describe the normal mechanism for opening a CFTR Cl- channel

Answer 7

increase cAMP –> activated PKA –> phosphorylation of R domain –>2 ATP bind R domaim –>opening of channel

Question 8

What happens when a CF patient has a decreased amount of airway surface liquid volume?

Answer 8

The mucus becomes viscous, bacteria accumulate leading to colonization and inflammation, infection, mucus plugging

Question 9

What defect does G542X cause in CF patients?

Answer 9

Additional stop codon which cause mRNA to degrade and no protein to be synthesized.

Question 10

Name 5 clinical outcomes of Cystic Fibrosis

Answer 10

progressive lung disease, exocrine pancreas, diabetes, intestinal defects, male infertility

Question 11

What bacteria are common in CF patients?

Answer 11

s. aureus, pseudomonas arginasas, Burkholderia cepharia, Aspergillus fummigatus, H. influenza