Lysosomal Storage Diseases

Question 1

Fabry disease. Give enzyme, substrate, inheritance, findings.

Answer 1

a-galactosidase A. Cermide trihexoside. XR. Peripheral neuropathy, angiokeratoas, cardio/renal disease.

Question 2

Gaucher disease. Give enzyme, substrate, inheritance, findings.

Answer 2

MOST COMMON. Glucocerebrosidase (B-glucosidase). Glucocerebroside. AR. Gaucher cells (lipid-laden macrophages appearing as crumpled tisue paper), hepatosplenomegaly, pancytopenia, aseptic necrosis of bone.

Question 3

Niemann-Pick. Give enzyme, substrate, inheritance, findings.

Answer 3

Sphingomyelinase. Sphingomyelin. AR. Progressive neurodegeneration, “cherry-red” macula, foam cells (lipid-laden macrophages), hepatosplenomegaly.

Question 4

Tay-Sachs. Give enzyme, substrate, inheritance, findings.

Answer 4

Hexosaminidase A. GM2-ganglioside. AR. Progresive neurodegeneration, “cherry-red” macula, developmental delay, “onion-skin” lysosomes, NO hepatosplenomegaly.

Question 5

Krabbe disease. Give enzyme, substrate, inheritance, findings.

Answer 5

Galactocerebrosidase. Galactocerebroside psychosine. AR. Peripheral neuropathy, optic atrophy, globoid cells, developmental delay.

Question 6

Metachromatic leukodystrophy. Give enzyme, substrate, inheritance, findings.

Answer 6

Arylsulfatase A. Cerebroside sulfate. AR. Central & peripheral demyelination w/ ataxia & dementia.

Question 7

Adrenoleukodystrophy. What is deficient? How is this inherited?

Answer 7

Impaired addition of coenzyme A to VLCFA, leading to excessive build-up of VLCFA in the brain, adrenals, testes. XR.

Question 8

Hurler syndrome. Give enzyme, substrate, inheritance, findings.

Answer 8

a-L-iduronidase. Heparan & dermatan sulfate. AR. Developmental delay, gargoylism, corneal clouding, hepatosplenomegaly, airway obstruction.

Question 9

Hunter syndrome. Give enzyme, substrate, inheritance, findings.

Answer 9

Iduronate sulfatase. Heparan& dermatan sulfate. AR. Mild Hurler + aggressive behavior W/O corneal clouding.