Disease Information for McArdle's syndrome

McArdle"s disease;Also known as: Cori"s syndrome; McArdle’s syndrome; Maladie de McArdle-Schmid-Pearson; Cori’s type V glycogenosis; McArdle-Schmid-Pearson syndrome; A condition caused by an inborn abnormal accumulation of glycogen in muscle tissue due to a phosphorylase B deficiency; Symptoms are muscular pain, fatigability, and muscle cramping following exercise; Rest makes symptoms disappear; Size and initial power tone of muscle normal at outset of exercise; Onset usually in childhood, although diagnosis may be made later; The affected children appear normal early in life, but late in childhood and adolescence they tire easily; During the later stages of adolescence and adulthood, they suffer from severe cramps and myoglobinuria after exercise; Unlike other types of glycogenosis the disease is not fatal and the missing enzyme does not impair the functioning of other body systems;Inheritance is autosomal recessive but a Dominant form also reported; case: 30 years of age male who experienced pain followed by weakness and stiffness after exercise as having been present "all his life", but doctors had dismissed his symptoms as hysterical; unlike ordinary cramps, those experienced by the patient were electrically silent, and that his venous lactate level failed to increase after ischaemic exercise; He realised that this was the same phenomenon that occurs when muscle is poisoned by iodoacetate, a substance that blocks the breakdown of glycogen into glucose and prevents the formation of lactic acid;

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McArdle syndrome;Glycogen storage disease type V; Myophosphorylase deficiency; Muscle glycogen phosphorylase deficiency; PGYM deficiency; McArdle syndrome is a disease characterized by an inability to break down glycogen; Glycogen an important source of energy that is stored in muscle tissue; McArdle syndrome results from a mutation in a gene; The gene makes an enzyme called glycogen phosphorylase; glycogen cannot be broken down in the muscles; This may lead to weakness, cramps, and muscle pain; The disease is inherited as an autosomal recessive genetic disorder;

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