Cardiomyopathy and exercise intolerance in muscle glycogen storage disease 0.

• Storage of glycogen is essential for glucose homeostasis and for energy supply during bursts of activity and sustained muscle work. We describe three siblings with profound muscle and heart glycogen deficiency caused by a homozygous stop mutation (R462-->ter) in the muscle glycogen synthase gene. The oldest brother died from sudden cardiac arrest at the age of 10.5 years. Two years later, an 11-year-old brother showed muscle fatigability, hypertrophic cardiomyopathy, and an abnormal heart rate and blood pressure while exercising; a 2-year-old sister had no symptoms. In muscle-biopsy specimens obtained from the two younger siblings, there was lack of glycogen, predominance of oxidative fibers, and mitochondrial proliferation. Glucose tolerance was normal.

Keyword

Biopsy

Cardiomyopathy

Hypertrophic

genetics

Child

Child

Preschool

Codon

Nonsense

DNA Mutational Analysis

Exercise Tolerance

genetics

Female

Glucose Tolerance Test

Glycogen

analysis

Glycogen Storage Disease

genetics

Glycogen Synthase

deficiency

genetics

Homozygote

Humans

Liver Glycogen

analysis

Male

Mitochondria

metabolism

Muscle

Skeletal

enzymology

pathology

Myocardium

enzymology

pathology

Publication and Content Type

ref (subject category)

art (subject category)