Organic Acid

Question 1

[Met/OA/Basic]

Common complications for organic acidemias? (2)

Answer 1

Bone marrow suppression
Pancreatitis

Question 2

[Met/OA/PA]

Enzyme defect in propionic acidemia?

Answer 2

Propionyl-CoA carboxylase (PCC)

Question 3

[Met/OA/PA]

Newborn screening finding for propionic acidemia?

Answer 3

Elevated C3 (propionylcarnitine)

Question 4

[Met/OA/PA]

Amino acids converted by propionyl CoA? (4)

Answer 4

Valine
Methionine
Isoleucine
Threonine
(VoMIT)

Question 5

[Met/OA/PA]

Gene defect for propionic acidemia?

Answer 5

PCCA or PCCB
(Propionyl-CoA Carboxylase)

Question 6

[Met/OA/PA]

Chronic complications of propionic acidemia? (4)

Answer 6

Growth impairment
Intellectual disability, seizures, basal ganglia lesions
Pancreatitis
Cardiomyopathy

Question 7

[Met/OA/PA]

Acute management of propionic acidemia? (3)

Answer 7

Intravenous glucose and lipids
Protein restriction to reduce propiogenic precursors
Intravenous carnitine

Question 8

[Met/OA/PA]

Chronic management of propionic acidemia? (3)

Answer 8

Protein restriction
Carnitine
Oral metronidazole (reduce gut microbactrium to produce pronionic acid)

Question 9

[Met/OA/MMA]

Enzyme defect in Methylmalonic Acidemias? (3)

Answer 9

Methylmalonyl-CoA mutase
Cofactor, 5-deoxy-adenosyl-cobalamin (cblA, cblB, or cblD-MMA)
Methylmalonyl-CoA epimerase

Question 10

[Met/OA/MMA]

Three phenotypes of Methylmalonic Acidemias?

Answer 10

Infantile/non-B12-responsive
Partially deficient or B12-responsive phenotypes
Methylmalonyl-CoA epimerase deficiency

Question 11

[Met/OA/MMA]

Presentation of Methylmalonyl-CoA epimerase deficiency? (2)

Answer 11

Wide range from complete absence of symptoms to severe metabolic acidosis
Ataxia, dysarthria, hypotonia, mild spastic paraparesis, and seizures

Question 12

[Met/OA/MMA]

Late complications of Methylmalonic Acidemias? (5 systems)

Answer 12

1. Neuro: intellectual disability, metabolic stroke, optic nerve atrophy
2. Cardiac: arrhythmias and/or cardiomyopathy
3. GI: Pancreatitis, growth failure, liver steatosis/fibrosis/cancer
4. Renal: tubulointerstitial nephritis, renal cancer
5. Immune: functional immune impairment, bone marrow failure

Question 13

[Met/OA/IVA]

Enzyme defect in Isovaleric acidemia?

Answer 13

Isovaleryl-CoA dehydrogenase in leucine metabolism

Question 14

[Met/OA/IVA]

Newborn with organic acidemia and sweaty feet smell? (2)

Answer 14

Isovaleryl-CoA dehydrogenase
Multiple acyl-CoA dehydrogenase deficiency

Question 15

[Met/OA/Biotinidase]

Presentations of biotinidase deficiency? (2 systems)

Answer 15

Neuro: seizures, hypotonia, ataxia, developmental delay, vision problems, hearing loss
Skin: cutaneous abnormalities (e.g., alopecia, skin rash, candidiasis)

Question 16

[Met/OA/MCD]

Classic triad of carboxylase deficiency?

Answer 16

Encephalopathy
Alopecia
Rash
(enCe, Alo, Rash CAR)

Question 17

[Met/OA/MCD]

Two examples of multiple carboxylase deficiency?

Answer 17

Biotinidase deficiency
Holocarboxylase synthetase deficiency

Question 18

[Met/OA/MADD]

Biochemical characteristics for acute presentation of type I or II Multiple acyl-CoA dehydrogenase deficiency (MADD)? (2)

Answer 18

1. Severe metabolic acidosis, profound hypoglycemia, hyperammonemia
2. Metabolic decompensation resembling Reye syndrome (acute noninflammatory encephalopathy with fatty liver failure)

Question 19

[Met/OA/MADD]

Types of Multiple acyl-CoA dehydrogenase deficiency? (3)

Answer 19

1. type I (neonatal onset with congenital anomalies)
2. type II (neonatal onset without congenital anomalies)
3. type III (late onset)

Question 20

[Met/OA/MADD]

Characteristics of type I or II Multiple acyl-CoA dehydrogenase deficiency?
- age of onset
- 4 organ systems

Answer 20

1. in the neonatal period
2. dysmorphic facial features
3. Hypertrophic cardiomyopathy
4. large cystic kidneys, hypospadias and chordee in males,
5. neuronal migration defects (heterotopias) on brain MRI
   (with metabolic decompensation like Reye syndrome)

Question 21

[Met/OA/MADD]

Congenital anomalies of Multiple acyl-CoA dehydrogenase deficiency? (4)

Answer 21

1. Dysmorphic facial features
2. Large cystic kidneys
3. Hypospadias and chordee in males
4. Neuronal migration defects (heterotopias) on brain MRI

Question 22

[Met/OA/MADD]

Characteristics of type 3 Multiple acyl-CoA dehydrogenase deficiency? (3)
- Age of onset
- Typical Presentation
- Rare symptoms

Answer 22

1. From infancy to adulthood
2. Muscle weakness, exercise intolerance, and/or muscle pain
3. Rarely, severe sensory neuropathy, proximal myopathy

Question 23

[Met/OA/MADD]

Treatment for Multiple Acyl-CoA Dehydrogenase Deficiency? (4)

Answer 23

1. Limitation of protein and fat in the diet
2. Avoidance of prolonged fasting
3. High-dose riboflavin
4. Carnitine supplementation

Question 24

[Met/OA/MADD]

Current term of Glutaric Acidemia II?

Answer 24

Multiple Acyl-CoA Dehydrogenase Deficiency

Question 25

# [Met/OA/MADD] Synonyms for Multiple Acyl-CoA Dehydrogenase Deficiency (MADD)? (2)

Answer 25

Electron Transfer Flavoprotein Dehydrogenase Deficiency Glutaric Acidemia II or aciduria II