Hypokalemic Periodic Paralysis
Hypokalemic periodic paralysis (HOKPP) is characterized by episodes of muscle paralysis associated with a fall in blood potassium levels (hypokalemia). Episodes typically involve a temporary inability to move muscles in the arms and legs. The first attack usually occurs in childhood or adolescence. Attacks can last for hours or days, and the frequency of attacks varies among people with HOKPP. The frequency is usually highest between the ages of 15 and 35, and then decreases with age. Some people with HOKPP also develop late-onset proximal myopathy.
HOKPP can be caused by mutations in the CACNA1S, SCN4A, or KCNJ18 gene. Inheritance is autosomal dominant. Treatment varies depending on the intensity and duration of attacks. Minor attacks may go away on their own, while treatment for moderate or severe attacks may involve taking potassium salts or intravenous (IV) potassium.
HOKPP can be caused by mutations in the CACNA1S, SCN4A, or KCNJ18 gene. Inheritance is autosomal dominant. Treatment varies depending on the intensity and duration of attacks. Minor attacks may go away on their own, while treatment for moderate or severe attacks may involve taking potassium salts or intravenous (IV) potassium.