Chapter 3- lysosomal storage disorders

Question 1

FABRY DISEASE

Answer 1

1. Inheritance: XR
2. Deficient enzyme: a-galactosidase
3. Accumulated metabolite: ceramide trihexoside
4. Physical: angiokeratomas, cardiac and renal involvement, painful neuropathy

Question 2

GAUCHER DISEASE

Answer 2

1. Inheritance: AR
2. Deficient enzyme: b-glucocerebrosidase
3. Accumulated metabolite: glucocerebroside
4. Physical: Gaucher cells (macrophages that look like crumpled tissue paper), hepatosplenomegaly, pancytopenia, severe bone and joint pain

Question 3

HURLER SYNDROME

Answer 3

1. Inheritance: AR
2. Deficient enzyme: a-L-iduronidase
3. Accumulated metabolite: dermatan and heparan sulfate
4. Physical: gargoylism, corneal clouding, hepatosplenomegaly, developmental delay

Question 4

HUNTER SYNDROME

Answer 4

1. Inheritance: XR
2. Deficient enzyme: iduronate sulfatase
3. Accumulated metabolite: dermatan and heparan sulfate
4. Physical: similar to Hurler syndrome but milder and no corneal clouding

Question 5

NIEMANN-PICK DISEASE

Answer 5

1. Inheritance: AR
2. Deficient enzyme: sphingomyelinase
3. Accumulated metabolite: sphingomyelin
4. Physical: hepatosplenomegaly, cherry-red spot in macula, foam cells, progressive neurodegeneartion

Question 6

TAY SACHS DISEASE

Answer 6

1. Inheritance: AR
2. Deficient enzyme: b-hexosaminidase A
3. Accumulated metabolite: GM2 ganglioside
4. Physical: cherry-red spot in macula, progressive neurodegeneration, no hepatosplenomegaly

Question 7

KRABBE DISEASE

Answer 7

1. Inheritance: AR
2. Deficient enzyme: galactocerebrosidase
3. Accumulated metabolite: galactosylsphingosine and galactocerebroside
4. Physical: progressive neurodegeneration, optic atrophy

Question 8

METACHROMATIC LEUKODYSTROPHY

Answer 8

1. Inheritance: AR
2. Deficient enzyme: Arylsulfatase A
3. Accumulated metabolite: Cerebroside sulfate
4. Physical signs and symptoms: muscle wasting, dementia, ataxia