Glycogen Storage Disease
Also written as GSD.
glycogen storage disease (GSD) type II (Pompe’s disease)— IEM, seizures are a late aspect following progressive signs
What our notes say
- glycogen storage disease (GSD) type II (Pompe’s disease)— IEM, seizures are a late aspect following progressive signs (Devendra K. Gupta, Krishna M. Goel - Hutchison’s Paediatrics. chdhe-Jaypee Broth)
- Glycogen storage disease (GSD) type I is also known as _ disease; (Biochemistry End-of-Year 2015 — Past Paper)
- Inborn errors (rare): Glycogen storage disease, fatty acid oxidation defects — Present in childhood, often missed (Hypoglycaemia)
- Glycogen storage disease (II, III)\nFibrotic\nRadiation (Harrisons Cardiovascular Medicine 2nd Edition 2)
- accumulation, particularly with glycogen storage disease Figure 21-13 (Harrisons Cardiovascular Medicine 2nd Edition 2)
- 20.4: Four-month infant with glycogen storage disease type Ia.\nNote rounded facies and gross hepatomegaly (Devendra K. Gupta, Krishna M. Goel - Hutchison’s Paediatrics. chdhe-Jaypee Broth)
Study material on Glycogen Storage Disease
- Devendra K. Gupta, Krishna M. Goel - Hutchison’s Paediatrics. chdhe-Jaypee Brothers (2012)
- Harrisons Cardiovascular Medicine 2nd Edition 2
- Biochemistry End-of-Year 2015
- Chemical Pathology MCQs: Clinical Chemistry, Endocrine & Renal — MCQ Bank
- Year 3: Endocrine and Metabolic Pathology — Part 2 — MCQ Bank
Practice questions on Glycogen Storage Disease
Von Gierke's disease (Type 1 glycogen storage disease) is caused by
- Acid maltase (alpha-glucosidase) deficiency → glycogen in lysosomes
- Myophosphorylase deficiency → glycogen in muscle
- Glucose-6-phosphatase deficiency → glycogen and fat accumulation in liver and kidneys
- Debranching enzyme deficiency → limit dextrin accumulation
Answer: C. Von Gierke (GSD Type 1): G6Pase deficiency → glucose cannot be released from liver → severe fasting hypoglycemia + massive hepatomegaly + renomegaly + hyperlipidemia + hyperuricemia (gout). Lactic acidosis. Treatment: continuous glucose/cornstarch feeds.
Pompe's disease (GSD Type 2) is caused by acid maltase deficiency and is unique among glycogen storage diseases because
- Glycogen accumulates in lysosomes (a lysosomal storage disease)
- It causes severe hyperglycemia
- It affects only the liver
- It is X-linked recessive
Answer: A. Pompe = only GSD that is also a lysosomal storage disease. Glycogen accumulates in lysosomes of heart, skeletal muscle, liver. Infantile form: cardiomegaly, hypotonia, respiratory failure → death by age 2. Treatment: enzyme replacement (alglucosidase alfa). Remember: "Pompe trashes the pump" (heart).