Aminoacidopathies

Question 1

4 parts of amino acid structure

Answer 1

Amino group
Carboxylic group
Side chain
Hydrogen atom

Question 2

3 “pathways” for amino acids

Answer 2

Anabolism
Conversation
Excretion

Question 3

Enzyme deficient in PKU

Answer 3

Phenylalanine hydroxylase

Question 4

Gene and inheritance in PKU

Answer 4

PAH, AR

Question 5

Treatment for PKU

Answer 5

Dietary phe restriction

Dietary phe-free protein formula

Question 6

Sapropterin

Answer 6

Oral form of BH4

Less response in those with no enzyme activity

Question 7

Phenylalanine Ammonium Lyase Injection

Answer 7

Enzyme catalyzes alternative phe degradatio pathway

Question 8

Large neutral aa

Answer 8

Compete with phe at the BBB to block phe entry into the brain

Question 9

Risks with maternal PKU

Answer 9

Microcephaly, MR
IUGR
CHD

Question 10

Tyrosinemia Type 1 enzyme deficiency

Answer 10

Fumarylacetoacetate hydrolase

Question 11

Tyrosinemia Type 1 inheritance and gene

Answer 11

AR, FAH

Question 12

Tyrosinemia treatment

Answer 12

Dietary phe and tyr restriction
Dietary supplement with phe/tyr-free formula
nitisinone
Liver transplant

Question 13

MSUD enzyme deficiency

Answer 13

Branch chain keto-acid dehydrogenase deficiency

Question 14

MSUD inheritance and gene

Answer 14

AR, BCKDHA/BCKDHB/DBT/DLDE3

Question 15

MSUD Treatment

Answer 15

BCAA- free calories
Thiamine supplementation
Hemodialysis/hemofiltration

Question 16

Homocystinuria enzyme deficiency

Answer 16

Cystathionine beta-synthase

Question 17

Homocystinuria inheritance and gene

Answer 17

AR, CBS

Question 18

Treatment of Homocystinuria

Answer 18

Restrict met

Met-free formi.a

Question 19

Supplements to use to homocystinuria

Answer 19

Vit b6

Betaine

Question 20

Non-ketotic hyperglycemia enzyme deficiency

Answer 20

Glycine cleavage enzyme

Question 21

NKH inheritance and gene

Answer 21

AR, GLDC/AMT/GCSH

Question 22

Treatment for NKH

Answer 22

Sodium benzoate
Dextromthorphan
Glycine restriction

Question 23

Untreated PKU in Neonatal Period

Answer 23

Fair skin and hair pigmentation

Mousy/Musty odor

Question 24

Untreated PKU after infancy

Answer 24

Developmental delay
Autism, microcephaly, behaviour issues
Many with epilepsy, eczema

Question 25

PKU plasma AA

Answer 25

Increased Phe | Increased phe to tyr ratio

Question 26

PKU prenatal testing

Answer 26

Possible if familial mutation known

Question 27

Untreated Tyrosinemia Type 1 in infancy

Answer 27

Cabbage-like odor to urine Liver and renal dysfunction Rickets, poor growth Neurologic crises

Question 28

Untreated Tyrosinemia Type 1 after infancy

Answer 28

Typically death by age 10

Question 29

Tyrosinemia Type 1 plasma AA

Answer 29

Elevated tyr | Elevated succinylacetone in blood

Question 30

Prenatal dx of Tyrosinemia Type 1

Answer 30

Molecular testing if familial mutation known | Succinylacetone measured in amniotic fluid

Question 31

Untreated MSUD 12-24 hours after birth

Answer 31

Maple syrup odor in urine and ear wax

Question 32

Untreated MSUD 5 days after birth

Answer 32

Irritability and decreased feeding | Encephalopathy/ cerebral edema

Question 33

Untreated MSUD 7-10 days after birth

Answer 33

Coma Respiratory failure Death in weeks

Question 34

MSUD AA profile

Answer 34

Elevated: leucine, isoleucine, valine Presence: allo-isoleucine

Question 35

MSUD prenatal dx

Answer 35

Molecular testing if familial mutation is known | BCKD enzyme activity on amnio/CVS

Question 36

Untreated Homocystinuria Features

Answer 36

Marfanoid skeletal changes Ectopia lentis Neuropsychiatric disease Veinous/Arterial Thromboembolism

Question 37

Homocystinuria plasma AA

Answer 37

Elevated: homocysteine and methionine | Low/absent: cysteine

Question 38

Untreated NKH symptoms

Answer 38

Intractable neonatal seizures Hypotonia Encephalopathy within first few days of life

Question 39

NKH plasma AA

Answer 39

Abnormal CSF to plasma glycine ratio

Question 40

Prenatal Dx for NKH

Answer 40

Molecular testing of familial mutation

Question 41

Prenatal dx for Homocystinuria

Answer 41

Molecular testing of familial mutation CBS enzyme activity assay in amniocytes (not CVS) Amniotic fluid homocysteine levels