Periodic paralysis

Bertrand Fontaine
Advances in Genetics 2008, 63: 3-23
Periodic paralyses are rare diseases characterized by severe episodes of muscle weakness concomitant to variations in blood potassium levels. It is thus usual to differentiate hypokalemic, normokalemic, and hyperkalemic periodic paralysis. Except for thyrotoxic hypokalemic periodic paralysis and periodic paralyses secondary to permanent changes of blood potassium levels, all of these diseases are of genetic origin, transmitted with an autosomal-dominant mode of inheritance. Periodic paralyses are channelopathies, that is, diseases caused by mutations in genes encoding ion channels. The culprit genes encode for potassium, calcium, and sodium channels. Mutations of the potassium and calcium channel genes cause periodic paralysis of the same type (Andersen-Tawil syndrome or hypokalemic periodic paralysis). In contrast, distinct mutations in the muscle sodium channel gene are responsible for all different types of periodic paralyses (hyper-, normo-, and hypokalemic). The physiological consequences of the mutations have been studied by patch-clamp techniques and electromyography (EMG). Globally speaking, ion channel mutations modify the cycle of muscle membrane excitability which results in a loss of function (paralysis). Clinical physiological studies using EMG have shown a good correlation between symptoms and EMG parameters, enabling the description of patterns that greatly enhance molecular diagnosis accuracy. The understanding of the genetics and pathophysiology of periodic paralysis has contributed to refine and rationalize therapeutic intervention and will be without doubts the basis of further advances.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"

We want to hear from doctors like you!

Take a second to answer a survey question.