Inborn Errors of Metabolism

Question 1

What condition do you think of first if the patient smells like cabbage?

Answer 1

Tyrosinemia

Question 2

What condition do you think of first if the patient smells musty?

Answer 2

PKU

Question 3

If the patient is presenting with fasting intolerance, hypoketoic hypoglycemia, low carnitine, and cardiomyopathy, what disorder is most likely?

Answer 3

LCAD/VLCAD - longer chains impact muscles in addition to the brain

Question 4

Black urine is a cardinal feature of what disorder?

Answer 4

Alkaptonuria

Question 5

What is the treatment for alkaptonuria?

Answer 5

Limit Tyr and Phe (because this is a problem of the tyrosine breakdown pathway)
Nitisone will inhibit the enzyme that results in the build-up of homogentistic acid

Question 6

Patient presents with:
bone/cartilage necrosis
height loss due to spinal changes
aortic/mitral valve calcifications

Answer 6

Alkaptonuria

Question 7

Phenyketonuria

clinical presentation
treatments

teratogenic effects

Answer 7

Clinical presentation:
fair skin and hair
light sensitivity
hair loss
eczema

detectable through newborn screening
need to limit phenylalanine –> low protein diet, supplement other amino acids

supplementation of a form of the BH4 cofactor can help lower Phe levels

High Phe levels is teratogenic during pregnancy - causes microcephaly, heart defects, IUGR, DD

Question 8

Identifying feature of MPS I

Answer 8

vision loss due to corneal clouding

Question 9

Identifying feature of MPS II

Answer 9

X-linked

Question 10

Identifying feature of MPS III

Answer 10

ne dermatin sulfate in the urine

Question 11

Identifying feature of MPS IV

Answer 11

primarily skeletal, joint laxity

Question 12

Identifying feature of MPS VI

Answer 12

no intellectual disability