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Metabolic Diseases

1 out of 5

Child with recurrent hypoglycemic attack and hepatomegaly is likely to have – (AIPG 2010)

A Von Gierke's disease
B Neonatal diabetes

C Neonatal hepatitis
D Galactosemia

Ans. A

Von Gierke's disease

Recurrent hypoglycemic attack with hepatomegaly is Seen in Type I glycogen storage disease (Von Gierke disease).

Glvcoqen storage diseases

o Glycogen storage diseases result from a hereditary deficiency ofone ofthe enzymes involved in the synthesis or

o sequential degradation of glycogen.

o Clinical features depend on type of enzyme deficiency and organ involvement.

o Glycogen storage diseases can be divided into :-

1) Hepatic form (Liver glycogenoses)

a. Liver is the key player in glycogen metabolism.

b. It contains enzymes that synthesize glycogen for storage and ultimately break it down into free glucose, which is then released into blood.

c. So, An inherited deficiency of hepatic enzymes that are involved in glycogen metabolism leads to

i. Storage of glycogen in liver + Hepatomegaly.

ii. Reduction in blood glucose + Hypoglycemia.

d. Examples of liver glycogenoses are -

i. Type I glycogenosis Glucose - 6 - phosphatase deficiency (Von Gierke disease).

ii. Type III glycogenosis Debranching enzyme def.

iii. Type IV glycogenesis Branching enzyme def.

iv. T1:pe VI gltcogenosis Liver phosphorylase def.

2) Myopathic form (Muscular glycogenoses)

a. In skeletal muscle, as opposed to the liver, glycogen is used predominantly as a source of energy.

b. This is derived by glycolysis, which leads ultimately to the formation of lactate.

c. So, enzyme deficiency leads to -

i. Glycogen deposition in muscle

ii. Muscle cramp after exercise

iii. Exercise - induced rise in blood lactase levels owing to block in glycolysis

iv. There may be myoglobinemia

d. Examples are -

i. Type V glycogenosis-phosphorylase deficiency (McArdle disease).

ii. Type VII glycogenosis-phosphofructokinase def.

3) Miscellaneous types

a. Associated with glycogen storage in many organs and death in early life.

b. Examples-

i. Type II glycogenosis -+ Acid maltase deficiency (Pompe s disease)