Sodium channel mutations in acetazolamide‐responsive myotonia congenita, paramyotonia congenita, and hyperkalemic periodic paralysis

@article{Ptek1994SodiumCM,
  title={Sodium channel mutations in acetazolamide‐responsive myotonia congenita, paramyotonia congenita, and hyperkalemic periodic paralysis},
  author={Louis J. Pt{\'a}{\vc}ek and Rabi Tawil and Robert C. Griggs and Giovanni Meola and Philip G. McManis and Richard J. Barohn and Jerry R. Mendell and Chris M. Harris and Robert M. Spitzer and F. Santiago and M. Leppert},
  journal={Neurology},
  year={1994},
  volume={44},
  pages={1500 - 1500}
}
Hyperkalemic periodic paralysis (hyperKPP) and paramyotonia congenita (PC) are genetic muscle disorders sharing the common features of myotonia and episodic weakness. In hyperKPP, patient symptoms and signs are worsened by elevated serum potassium, whereas in PC, muscle cooling exacerbates the condition. There are patients in whom features of both hyperKPP and PC are present. These diseases result from molecular alterations in the adult skeletal muscle sodium channel. This report summarizes our… 

Figures from this paper

Mutation in the S4 segment of the adult skeletal sodium channel gene in an Italian Paramyotonia Congenita (PC) family

A mutation in an S4 segment of the adult skeletal muscle sodium channel in a clinically-defined Italian family is described that leads to the paramyotonia congenita (PC) phenotype with dominant autosomal inheritance and temperature-related symptoms (regional weakness following cooling and exercise), present since childhood in all of the affected family members.

From mutation to myotonia in sodium channel disorders

Muscle channelopathies and electrophysiological approach

Five electromyographic patterns (I-V) that may be used in clinical practice as guides for molecular diagnosis are discussed and can be used as a functional test in electromyography to improve the diagnosis of these muscle disorders.

Lack of sodium channel mutation in an Italian family with paramyotonia congenita.

The existence of a second gene different from SCN4A that can give rise to a clinical PC phenotype can be speculated upon.

Skeletal muscle channelopathies: nondystrophic myotonias and periodic paralysis.

Recent discoveries in the skeletal muscle channelopathies have increased understanding of the genetics and pathophysiology of these diseases, and studies reporting imaging techniques raise the possibility of improved disease monitoring and better outcome measures for clinical trials.

Hypokalemic periodic paralysis and the dihydropyridine receptor (CACNL1A3): genotype/phenotype correlations for two predominant mutations and evidence for the absence of a founder effect in 16 caucasian families.

It is shown that a founder effect is unlikely to account for the two predominant mutations in hypoPP, and analysis of the clinical characteristics of both groups of families demonstrated that incomplete penetrance is a distinctive feature of the Arg528His mutation.

The familial periodic paralyses and nondystrophic myotonias.

  • L. Ptáček
  • Medicine
    The American journal of medicine
  • 1998

Hypokalaemic periodic paralysis type 2 caused by mutations at codon 672 in the muscle sodium channel gene SCN4A.

A complete penetrance in men and women, an early age at onset, postcritic myalgias and an increased number and severity of attacks induced by acetazolamide are observed in a large hypoPP family carrying an SCN4A mutation.
...

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