Aminoacidopathies (Inborn Errors of Metabolism)

Question 1

↓ phenylalanine hydroxylase or ↓ tetrahydrobiopterin (BH4)

Answer 1

PHENYLKETONURIA (PKU)

Question 2

↓ branched-chain alpha-ketoacid dehydrogenase (BCKAD)

Answer 2

MAPLE SYRUP URINE DISEASE (MSUD)

Question 3

↓ homogentisate oxidase

Answer 3

ALKAPTONURIA

Question 4

↓ Cystathionine synthase, 🠛 Methionine synthase, or ↓ Methylenetetrahydro folate reductase

Answer 4

HOMOCYSTINURIA

Question 5

Hereditary defect of renal proximal convoluted tubules and intestinal amino acid transporter

Answer 5

Cystinuria

Question 6

↑ phenylalanine → ↑phenyl ketones in the urine

Answer 6

PHENYLKETONURIA (PKU)

Question 7

Hereditary defect of renal proximal convoluted tubules and intestinal amino acid transporter

Answer 7

CYSTINURIA

Question 8

↑ branched-chain amino acids (leucine, isoleucine, and valine) and their alpha-ketoacids

Answer 8

MAPLE SYRUP URINE DISEASE (MSUD)

Question 9

↑ homogentisic acid

Answer 9

ALKAPTONURIA

Question 10

↑ Methionine
↑ Homocysteine

Answer 10

HOMOCYSTINURIA

Question 11

↑ “COLA”
* Cystine
* Ornithine
* Lysine
* Arginine

Answer 11

CYSTINURIA

Question 12

musty body odor, intellectual disability, growth retardation, seizures, fair complexion, eczema

Answer 12

PHENYLKETONURIA (PKU)

Question 13

vomiting, poor feeding, urine smells like maple syrup/burnt sugar, severe CNS defects, death

Answer 13

MAPLE SYRUP URINE DISEASE (MSUD)

Question 14

bluish-black connective tissue, ear cartilage, and sclerae (ochronosis); urine turns black on prolonged exposure to air

Answer 14

ALKAPTONURIA

Question 15

HOMOCYstinuria:
* Homocysteine in urine
* Osteoporosis
* Marfanoid habitus
* Ocular changes (lens subluxation)
* Cardiovascular effects (thrombosis and atherosclerosis leading to stroke and MI)
* kYphosis

Answer 15

HOMOCYSTINURIA

Question 16

Excess “COLA” in the urine (Cystine, Ornithine, Lysine, and Arginine).

Answer 16

CYSTINURIA