Newborn Screening

Question 1

What percentage of infants screen positive on the NBS?

Answer 1

0.1%

Question 2

What percentage of NBS are false positives? Why might you get a false positive? What disorder has an especially high fp?

Answer 2

90% Premature babies often have false positives because their liver has not taken over metabolism from the placenta as fast as a term infant. CAH

Question 3

When do you collect the first NBS sample? The second? What percentage of disorders are detected by each?

Answer 3

24-48 hours (90%). 5-10 days (10%).

Question 4

Which disorder is picked up better by a second NBS?

Answer 4

Homocystinuria

Question 5

What is one of the most common disorders detected by NBS?

Answer 5

Hypothyroidism

Question 6

Which of the following genotypes is most likely to cause CF?
Delta F508 + R117H/5T
Delta F508 + R117H/7T
Delta F508 + R117H/9T
R117H/7T + R117H/9T

Answer 6

Delta F508 + R117H/5T