Disease Of Amino Acid Metabolism

Front 1

What is the biochemical and molecular basis for the inborn errors in amino acid metabolism?

Back 1

Deficiency of enzyme activity, deficiency of enzyme protein, cofactor abnormalities, transport defects, defects in structural proteins

Front 2

What does CRM stand for and what does it mean?

Back 2

CRM= cross reactive material; defined as a prtoein produced by a mutant gene that reacts antigenically with antibody against the normal protein.

Front 3

What are the basic features of the inborn errors?

Back 3

1. Patients appear normal at birth
2. Autosomal recessive inheritance
3. Diagnosed by specific laboratory tests

Front 4

What is clinical heterogeneity?

Back 4

different patients with the same disorder expressing the trait differently

Front 5

What is biochemical heterogeneity?

Back 5

different patients with blocks in the same metabolic pathway having different accumulatins of metabolites

Front 6

What is molecular heterogeneity?

Back 6

different patients with different mutations in the same gene

Front 7

what is locus (genetic) heterogeneity?

Back 7

different genes that code for different enzymes within the same pathway

Front 8

what are the five deficiencies in the urea cycle?

Back 8

CPS, OTC, AS, AL, and arginase

Front 9

What are the causes of hyperamonemia?

Back 9

1. Liver disease
2. transient hyperammonemia of the newborn
3. Reye syndrome
4. Poisonings
5. Inborn errors of metabolism

Front 10

Which urea cycle deficiency differs due to the frequent absence of hyperammonemia and a clinical picture of spastic diplegia and is often diagnosed as cerebral palsy?

Back 10

Arginase deficiency

Front 11

What is the primary cause of PKU

Back 11

Deficiency of the liver enzyme phenylalanine hydroxylase (PAH)

Front 12

What is the incidence of PKU?

Back 12

The incidence is approximately 1:12,000

Front 13

What are the clinical features of PKU (untreated)?

Back 13

Normal appearing at birth; no acute illness

Seizures, hypopigmentation, eczema, "musty" odor, irreversible mental retardation

Front 14

what is the treatment for PKU?

Back 14

Dietary restriction (but not absence) of phenylalanine; recommended for life.

Front 15

What is the cause of nonketotic hyperglycinemia?

Back 15

Deficient activity of glycine cleavage system due to defect, in most cases of either the T or P protein of the glycine cleavage system complex.

Front 16

What is the acute presentation of nonketotic hyperglycinemia?

Back 16

Poor feeding, lethargy, intractable seizures, profound hypotonia, coma and death.

Front 17

Homocystinuria is caused by ?

Back 17

an inborn error in pathway of sulfur metabolism.

Front 18

What are the clinical features of homocystinuria?

Back 18

Marfan-like presentation with abormal long bone formation; dislocated lenses; blindness; increased risk for thromboembolytic events involving both large and small vessels, especially the brain; variable mental retardation.