GTR Home > Conditions/Phenotypes > Paramyotonia congenita of von eulenburg

Summary

Paramyotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in infancy or early childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Myotonia causes muscle stiffness that typically appears after exercise and can be induced by muscle cooling. This stiffness chiefly affects muscles in the face, neck, arms, and hands. Unlike many other forms of myotonia, the muscle stiffness associated with paramyotonia congenita tends to worsen with repeated movements. Most people—even those without muscle disease—feel that their muscles do not work as well when they are cold. This effect is dramatic in people with paramyotonia congenita. Exposure to cold initially causes muscle stiffness in these individuals, and prolonged cold exposure leads to temporary episodes of mild to severe muscle weakness that may last for several hours at a time. [from GHR]

Available tests

31 tests are in the database for this condition. Compare labs offering these tests.

Check Associated genes for additional relevant tests.

Associated genes

  • Also known as: HOKPP2, HYKPP, HYPP, NAC1A, Na(V)1.4, Nav1.4, SkM1, SCN4A
    Summary: sodium channel, voltage-gated, type IV, alpha subunit

Clinical features

Help
  • Muscle weakness
  • Feeding difficulties
  • Percussion myotonia
  • Neonatal hypotonia
  • Muscle hypertrophy
  • Myalgia
  • Handgrip myotonia
  • Muscle stiffness
  • Inspiratory stridor
  • Paradoxical myotonia
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