Glycogen Storage Disease (GSD)

Question 1

GSD Type-I

Von-Gierke Disease

Answer 1

Glucose 6-Phosphatase deficiency
Accumulation of Glucose 6-phosphate

Presents as:

1. Hepatomegaly & Steatosis
2. Fasting Hypoglycemia
3. Lactic acidosis
4. Hyperuricemia & Hyperlipidemia

Question 2

GSD Type-II

Pompe Disease

Answer 2

Deficiency of acid alpha-glucosidase (alpha-1,4 glucosidase or acid maltase)
Glycogen accumulated in lysosomes

Presents in early infancy as:

1. Severe Cardiomegaly
2. Normal glucose
3. Glycogen accumulated in lysosomes
4. Severe generalized hypotonia,
5. Macroglossia, and hepatomegaly

Question 3

GSD Type-III

Cori Disease

Answer 3

Deficiency of Debranching enzymes (Alpha-1,6 Glucosidase)
Accumulation of abnormal glycogen (with limit Dextrin structure)

Presents as:

1. Hepatomegaly
2. Ketotic hypoglycemia
3. Hypotonia & Weakness
4. Abnormal glycogen with very short outer chains

Question 4

GSD Type-IV

Anderson Disease

Answer 4

Glycogen brancher enzyme deficiency.

Presents as:

1. Hepatomegaly

Question 5

GSD Type-V

McArdle Disease

Answer 5

Muscle Phosphorylase deficiency
Accumulation of glycogen in muscles

Presents As:

1. Weakness & Fatigue with exercise
2. No rise in blood Lactate levels after exercise

Question 6

GSD Type-VI

HERS Disease

Answer 6

Liver Phosphorylase Deficiency.

Glycogen chain > G-1-P Hydrolysis of main chain.

Presents as:

1. Hypoglycemia (Mild)
2. Hepatomegaly