Definition - one of a group of muscle diseases that interfere with the processing of carbohydrates
for energy production

Cause - a genetic defect in the phosphoglycerate mutase enzyme, which normally helps break down glucose (sugar) for energy production

Onset - childhood to early adulthood

Symptoms - exercise intolerance, cramps, muscle pain and, sometimes, myoglobinuria (rust-colored urine indicating breakdown of muscle tissue); permanent weakness is rare

Progression - slowly progressive or not progressive

Inheritance - autosomal recessive, meaning caused by the contribution of a defective gene from each parent

Facts About Metabolic Diseases