Referenced in: none

Automatically associated channels: Kir2.3 , Nav1.4

Title: Normokalemic periodic paralysis revisited: does it exist?

Authors: Patrick F Chinnery, Timothy J Walls, Michael G Hanna, David Bates, Peter R W Fawcett

Journal, date & volume: Ann. Neurol., 2002 Aug , 52, 251-2

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12210802

Abstract
Normokalemic periodic paralysis (normoKPP) is well established in the literature, but there are doubts as to whether it exists as a discrete entity. Retrospective clinical and molecular analysis has confirmed suspicions that most normoKPP families actually have a variant of hyperkalemic periodic paralysis (hyperKPP) due to a mutation of the muscle-specific sodium channel gene (SCN4A). However, the original normoKPP family described by Poskanzer and Kerr (Poskanzer DC, Kerr DNS. A third type of periodic paralysis, with normokalemia and favourable response to sodium chloride. Am J Med 1961;31:328-342) has remained unchallenged. We identified the Met1592Val mutation of SCN4A in an affected descendent of this original normoKPP family. This is the final piece in the puzzle: normoKPP is actually a variant of hyperKPP and is not a distinct disorder.