Paralysis, Hyperkalemic Periodic
Synonyms
Adynamia Episodica Hereditaria
Adynamia Episodica Hereditaria with or without Myotonia
Disease, Gamstorp
Familial Hyperkalemic Periodic Paralysis
Gamstorp Disease
Gamstorp Episodic Adynamy
HyperKPP
HyperPP
Hyperkalemic Periodic Paralysis
Hyperkalemic Periodic Paralysis Type 2
Hyperkalemic Periodic Paralysis, Familial
Hyperkaliemic Periodic Paralysis Type 2
Myotonic Periodic Paralysis
Paralysis, Periodic, Hyperkalemic, Familial
Primary Hyperkalemic Periodic Paralysis
Sodium Channel Muscle Disease
An autosomal dominant familial disorder which presents in infancy or childhood and is characterized by episodes of weakness associated with hyperkalemia. During attacks, muscles of the lower extremities are initially affected, followed by the lower trunk and arms. Episodes last from 15-60 minutes and typically occur after a period of rest following exercise. A defect in skeletal muscle sodium channels has been identified as the cause of this condition. Normokalemic periodic paralysis is a closely related disorder marked by a lack of alterations in potassium levels during attacks of weakness. (Adams et al., Principles of Neurology, 6th ed, p1481)