myotonia congenita
Quick Summary
Myotonia congenita is a rare, inherited ion channel disorder characterized by the difficulty of voluntary muscles to relax after contraction. This condition is often caused by mutations in the CLCN1 gene, which disrupts chloride flow in skeletal muscle fiber cells, leading to prolonged muscle contractions.1
There are two main forms: Thomsen myotonia congenita (autosomal dominant) and Becker myotonia congenita (autosomal recessive). Symptoms, which can appear in childhood or adulthood, may include lid lag, difficulty swallowing or speaking, and in severe cases, rigid paralysis after quick movements. A notable feature is the "warm-up effect," where muscle function improves with repeated movement. Unlike myotonic muscular dystrophy, myotonia congenita does not typically involve muscle degeneration but can lead to muscle hypertrophy. Treatment may involve medications like mexiletine, quinine, or phenytoin, though no cure exists.12
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muscle diseaseIndications of muscle disease…of muscular dystrophy known as myotonia congenita, which combines increased muscle size with strength and stiffness. Pseudohypertrophy, muscular enlargement through deposition of fat rather than muscle fibre, occurs in other forms of muscular dystrophy, particularly the Duchenne type.
Read More…of muscular dystrophy known as myotonia congenita, which combines increased muscle size with strength and stiffness. Pseudohypertrophy, muscular enlargement through deposition of fat rather than muscle fibre, occurs in other forms of muscular dystrophy, particularly the Duchenne type.
Read More- muscle diseaseMyotonic diseases
Myotonia congenita, also known as Thomsen disease, is an autosomal dominant disorder, but it is not associated with any dystrophic features. The onset is at birth, usually with severe difficulty in relaxing the muscle after a forced contraction, such as a sneeze. Myotonic goats (fainting…
Read MoreMyotonia congenita, also known as Thomsen disease, is an autosomal dominant disorder, but it is not associated with any dystrophic features. The onset is at birth, usually with severe difficulty in relaxing the muscle after a forced contraction, such as a sneeze. Myotonic goats (fainting…
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nervous system diseaseGenetic dystrophies…failure of relaxation occurs in myotonia congenita but without the wasting features of myotonic dystrophy. Relaxation can be obtained with medications such as diphenylhydantoin and quinine.
Read More…failure of relaxation occurs in myotonia congenita but without the wasting features of myotonic dystrophy. Relaxation can be obtained with medications such as diphenylhydantoin and quinine.
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