Myotonia Congenita (Thomsen Disease)

Myotonia Congenita (Thomsen Disease)

Clinical Features

Following a forceful contraction the patient finds it difficult to relax the muscles. Mother may notice stiffness of tongue during feeding. Onset is between 3-6 years. There is sustained involuntary muscular contraction lasting for upto 30 seconds following a voluntary contraction.

Diagnosis

Diagnosis is confirmed by electromyography. With repetition the movements become normal. Cold and emotional stress aggravate the symptoms. The reflexes are normal and muscular atrophy does not occur.

Treatment

Quinine, Quinidine or phenytoin may give symptomatic relief.
Physiotherapy may help.

Potassium Releated Periodic Paralysis

General Considerations

These disorders are characterised by recurrent transient episodes of muscle weakness and have been classified into three types according to serum potassium level hypokalaemic, hyperkalemic and normokalaemic.