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

Cause - a genetic defect in the carnitine palmityl transferase 2 (CPT2) enzyme, which
normally escorts breakdown products of fats from the main part of the muscle cell into the mitochondria, where they can be further metabolized for energy

Onset - infancy to adulthood

Symptoms - episodic muscle pain, stiffness and tenderness; myoglobinuria (rust-colored urine indicating breakdown of muscle tissue) can occur; usually brought on by prolonged intense exercise, but illness, cold, stress, menstruation can also provoke symptoms

Progression - if enzyme completely lost, rapid progression leading to death in infancy; if some enzyme activity remains, little or no progression with normal strength between episodes

Inheritance - generally autosomal recessive, meaning caused by the contribution of a defective gene from each parent; some genetic defects cause symptoms even if the gene from only one parent contains the flaw (mutation)

Facts About Metabolic Diseases of Muscle