Flashcards in Lecture 26-Biochemical Metabolism Deck (25):
What are the symptoms of a UCD? What are the labs that show each of these?
- hyperammonemia: high ammonia and glutamine
- lethargy/coma: low ketones, proteins, reducing substrates, blood BUN, arginine
- respiratory alkalosis
Refresher: how do you treat UCDs?
- scavengers: sodium benzoate (glycine), phenylacetate: (glutamine)
- reduce protein intake
- reduce protein breakdown: insulin temporarily, high carb diet
- arginine supplementation
MSUD is a defect of what enzyme?
- branched chain ketoacid DH
MSUD results in accumulation of what?
- 2-oxo (keto)acids
What is a clinical way to determine MSUD disease? What are the labs results you can use to determine if it's MSUD (4)?
- Clinical: intense smell of urine
- characteristic plasma aa abnormalities
- increase in BCAA
- disturbed BCAA ratio
- lots of ketones
treatment for MSUD? (4)
- high energy, low protein TPN/enteral feeds (MSUD specific)
- leu restriction
- thiamine supplementation
What is the primary toxic aa?
what are the prognoses for MSUD? (4)
MMA/PA stand for _____
- methyl-malonyl CoA mutase
- proprionyl CoA carboxylase
MMA and PA do what?
- sequential steps in isoleucine and valine catabolism
- needed for odd chain FA breakdown
What are the symptoms of MMA/PA? (6)
- respiratory distress
- poor feeding
- abnormal muscle tone
- toxic encephalopathy
What is diagnostic of MMA/PA
- methylcitric acid
- 3OH propionate
What accumulates in both MMA and PA diseases? Why is this bad?
- proprionic acid
- converted into many UOA biproducts
What do the labs on MMA/PA show?
- metabolic acidosis with increased anion gap
- elevated amylase/lipase
How do you treat MMA/PA? (8)
- **promote anabolism
- **VOMIT restriction (aa)
- **carnitine supplementation
- biotin/cobalamin supplementation
- get rid of excess precursors
How do patients respond to treatment of MMA/PA?
- well if caught early and vitamin responsive, otherwise not well
Isovaleric acidemia is the result of a mutation in what? What kind of protein is this?
- isovaleryl-CoA DH
- mitochondrial flavoprotein in ETC
How do IVA patients generally present?
- Similar to MMA/PA but milder
- smell like sweaty gym socks
PKU is a deficiency in what enzyme?
- F-hydroxylase deficiency
PKU results in what symptoms? (3)
- autistic behavior
How do you treat IVA?
- promote anabolism
- give lots of gly and carnitine as a way to get rid of the Isovaleryl CoA
- restrict leucine
What is very effective at preventing further decompensation in IVA patients?
In the lecture, PKU was mentioned to emphasize _____
the importance of screening
What is PKU inheritance?