Look at this patient.



· Ask the patient whether or not there is any seasonal variation in symptoms -myotonia is worse in winter because of the cold.

· Take a family history (inheritance is usually autosomal dominant; gene on long arm of chromosome 7).


· Diffuse muscle hypertrophy.

· Myotonia - may be apparent while shaking hands with the person.


This patient has diffuse muscular hypertrophy with myotonia (lesion) due to Thomsen's disease (aetiology).


How is the disease recognized in infancy?

Myotonia is present from birth and may be recognized by the child's peculiar cry. Also noticed in early infancy are difficulty in feeding

and inability to reopen the eyes while having the face washed.

When does muscle hypertrophy manifest?

It is usually apparent in the second decade.

What is the cause of muscle hypertrophy?

It is caused by almost continual involuntary isometric exercise.

What is the life expectancy in such patients?

These patients have a normal life expectancy.

What drugs would you use to ameliorate the myotonia?

Procainamide, quinidine.

In which other conditions is myotonia seen?

· Myotonia dystrophica.

· Paramyotonia congenita (episodic myotonia after exposure to the cold).

· Following the administration of drugs such as clofibrate.

familyand himself in 1876.