Unit 2: Inborn Errors of Metabolism

Question 1

In OTC deficiency, there is decreased _______ and increased ________.

Answer 1

Citrulline; Glutamine

Question 2

In Tyrosinemia Type 1, _______ inhibits ______, which causes porphyria-like abdominal pain and peripheral neuropathy

Answer 2

Succinylacetone; delta-aminolevulinic acid dehydratase

Question 3

Name 3 signs of hyperammonemia

Answer 3

Encephalopathy, Coma, Irreversible neurologic damage

Question 4

Name 4 signs of maternal PKU syndrome, arising due to poorly controlled PKU in the mother.

Answer 4

Low birth weight, microcephaly, malformation, mental retardation

Question 5

Name the enzyme deficiency and inheritance pattern: Fabry Disease

Answer 5

Alpha-galactosidase; XL

Question 6

Name the enzyme deficiency and inheritance pattern: Gaucher Disease

Answer 6

Beta-glucosidase/glucocerebrosidase; AR

Question 7

Name the enzyme deficiency and inheritance pattern: Hunter Disease

Answer 7

Iduronate sulfatase; XL

Question 8

Name the enzyme deficiency and inheritance pattern: Hurler Disease

Answer 8

Alpha-iduronidase; AR

Question 9

Name the enzyme deficiency and inheritance pattern: McArdle Disease

Answer 9

Glycogen phosphorylase; AR

Question 10

Name the enzyme deficiency and inheritance pattern: Neimann-Pick Disease

Answer 10

Spingomyelinase; AR

Question 11

Name the enzyme deficiency and inheritance pattern: Pompe Disease

Answer 11

Alpha-glucosidase; AR

Question 12

Name the enzyme deficiency and inheritance pattern: Tay Sachs Disease

Answer 12

Beta-hexosaminidase A; AR

Question 13

Name the glycolipid diseases with FDA-approved ERTs (5).

Answer 13

Fabry, Gaucher, Hunter, Hurler, Pompe

Question 14

Name two ammonia-scavenging medications.

Answer 14

Sodium benzoate, sodium phenylacetate

Question 15

Name two glycolipid disorders with X-linked inheritance.

Answer 15

Fabry Disease, Hunter Disease

Question 16

What is the enzyme abnormality and inheritance in classic homocystinuria?

Answer 16

Cystathione-beta-synthase Deficiency; AR

Question 17

What is the enzyme abnormality and inheritance in MSUD?

Answer 17

Branch chain alpha-keto-acid Dehydrogenase; AR

Question 18

What is the enzyme abnormality and inheritance in PKU?

Answer 18

Phenylalanine Hydroxylase deficiency; AR

Question 19

What is the first-line treatment for classic homocystinuria?

Answer 19

B6/Pyridoxine

Question 20

What is the first-line treatment for Tyrosinemia Type 1?

Answer 20

NTBC

Question 21

What is the most common enzyme deficiency in urea cycle disorders? What is the inheritance pattern for this defect?

Answer 21

Ornithine Transcarboxylase Deficiency; X-linked

Question 22

Which amino acids should be restricted in Type 1 Tyrosinemia?

Answer 22

Tyr, Phe

Question 23

Which pathologic pattern? Acroparesthesias in children

Answer 23

Fabry Disease

Question 24

Which pathologic pattern? Adult proximal muscle weakness, respiratory failure/sleep apnea

Answer 24

Pompe Disease

Question 25

Which pathologic pattern? Ataxia, ketoacidotisis, hypoglycemia, coma

Answer 25

MSUD

Question 26

Which pathologic pattern? Bony pain due to avascular necrosis, hepatosplenomegaly, anemia, thrombocytopenia, restrictive lung disease, adult onset, normal intellect

Answer 26

Gaucher Disease

Question 27

Which pathologic pattern? Cherry red spot, increased startle reflex, no hepatosplenomegaly

Answer 27

Tay Sachs

Question 28

Which pathologic pattern? Children, course facies, hoarse voice, cognitive decline, frequent URIs, macroglossia, heart valve problems, hepatosplenomegaly

Answer 28

Hunter Disease

Question 29

Which pathologic pattern? Children, course facies, hoarse voice, cognitive decline, frequent URIs, macroglossia, heart valve problems, hepatosplenomegaly, corneal clouding, dysostosis multiplex

Answer 29

Hurler Disease

Question 30

Which pathologic pattern? Death around age 40 secondary to renal failure and cardiac complications

Answer 30

Fabry Disease

Question 31

Which pathologic pattern? Hypotonia, developmental delay, failure to thrive, spastic paraplegia

Answer 31

MSUD

Question 32

Which pathologic pattern? Infantile blindness, seizures, mental and motor deterioration

Answer 32

Tay Sachs

Question 33

Which pathologic pattern? Infantile muscle weakness and hypertrophic cardiomyopathy

Answer 33

Pompe Disease

Question 34

Which pathologic pattern? Involves accumulations of fumarylacetoacetate, maleylacetoacetate, and succinylacetone

Answer 34

Tyrosinemia Type 1

Question 35

Which pathologic pattern? Light hair, eczema, unfamiliar odor, seizures, growth delay, intellectual disabilities

Answer 35

PKU

Question 36

Which pathologic pattern? Liver disease and renal tubulopathy early in infancy

Answer 36

Tyrosinemia Type 1

Question 37

Which pathologic pattern? Marfanoid Stature, osteoporosis, scoliosis, recurrent thromboembolism, myopia, ectopia lentis, developmental disability, neuropsych symptoms

Answer 37

Classic Homocystinuria

Question 38

Which pathologic pattern? Muscle cramping/weakness, myoglobinuria, normal cognition and liver enzymes

Answer 38

McArdle Disease

Question 39

Which pathologic pattern? Poor feeding, progressive lethargy, mild hypoglycemia, ketoacidosis, coma and seizures in first week of life

Answer 39

MSUD

Question 40

Which pathologic pattern? Porphyria-like attack, corneal lesions, palmoplantar keratosis

Answer 40

Tyrosinemia Type 1

Question 41

Which pathologic pattern? Proteinuria, angiokeratomas on the trunk, renal failure, cardiac disease, chronic IBS

Answer 41

Fabry Disease

Question 42

Which pathologic pattern? Rickets due to renal tubulopathy, no apparent liver failure, late in infancy

Answer 42

Tyrosinemia Type 1

Question 43

Which pathologic pattern? Supranuclear gaze palsy, cherry red spots, massive hepatosplenomegaly

Answer 43

Neimann-Pick Disease

Question 44

Which supplementations should be considered for chronic treatment of MSUD?

Answer 44

Valine, isoleucine, Thiamine/B1

Question 45

Which supplements can be considered in classic homocystinuria? (5)

Answer 45

Betaine, Folate, B12, cysteine, methionine