Paramyotonia congenita or hyperkalemic periodic paralysis? Clinical and electrophysiological features of each entity in one family

Shari M. de Silva, Ralph W. Kuncl, John W. Griffin, David R. Cornblath, Steven Chavoustie

Research output: Contribution to journalArticle


The nosological distinction between paramyotonia congenita (PC) and hyperkalemic periodic paralysis (HPP) continues to generate debate. Recently, electrophysiological signs thought to be specific for each entity have been described and have been used to bolster the argument that the two disorders are distinct. We report a particularly instructive family wherein individual members had clinical features of either PC or HPP and electrophysiological features of both. We suggest that PC and HPP represent part of the spectrum of a single genetic disorder. Evoked response testing, with exercise and cold provocation, may be useful in determining the physiologic pattern that predominates in any one individual.

Original languageEnglish (US)
Pages (from-to)21-26
Number of pages6
JournalMuscle & nerve
Issue number1
StatePublished - Jan 1990



  • electrodiagnosis
  • hyperkalemic periodic paralysis
  • myotonia
  • paramyotonia congenita

ASJC Scopus subject areas

  • Physiology
  • Clinical Neurology
  • Cellular and Molecular Neuroscience
  • Physiology (medical)

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