Bethlem Myopathy

Definition

Definition of Bethlem Myopathy
Bethlem myopathy is an autosomal dominant myopathy, classified as a congenital form of muscular dystrophy, that is caused by a variation in one of the three genes coding for type VI collagen. These include COL6A1, COL6A2, and COL6A3.

Symptoms

Symptoms of Bethlem Myopathy
Bethlem Myopathy can present itself from birth till later adulthood.  BM is usually noticed when contractures of the ankles, fingers, elbows or other joints are present.  Individuals usually have limited physical stamina and strength.  Most of the muscles are effected by this disease with the exception of the heart muscle.  BM is usually a very slowly progressive disease where 2/3 of individuals will need some sort of mobility aid by age 50.  Some individuals may have breathing problems due to the weakness of muscles that aid the breathing process.  The degree of severeness varies.  BM patients often exhibit odd scarring like keloids or raised cigarette paper type scars of the skin.

Causes

Causes of Bethlem Myopathy
Consult with your doctor.

Diagnosis

Diagnosis of Bethlem Myopathy
The diagnosis of BM is usually suspected from the symptoms and examination, paying special attention to the features described above. Because it is a rare disorder not very many doctors have experience of these features and people with Bethlem myopathy may often have had other diagnoses suggested in the past.

It is often necessary to do a blood test and a muscle biopsy to exclude other conditions that can present in a similar fashion. The muscle biopsy is studied through a microscope to check how the muscle is put together and whether there is any evidence of it being damaged. In BM the muscle fibres, instead of being evenly sized, show some variation but no significant damage or scarring. With special stains we can also check for a special protein called laminin beta 1, which can sometimes be reduced. However this only provides additional evidence, as these findings are not entirely specific to BM. At present the diagnosis of BM is usually made by collating the information gathered from history and clinical examination with laboratory findings.

In some cases it is possible to prove the specific diagnosis by demonstrating a fault in one of the genes encoding for collagen VI. This can be done using a skin biopsy or blood sample. At present it is available on a research basis only and results take months to years to come through. However, we are hoping this will change over the coming year.

Treatment

Treatment of Bethlem Myopathy
At the moment, there is no cure, nor any specific drug treatment for Bethlem myopathy. However, there are ways, described below, of helping to alleviate the effects of the condition and to prevent complications from occurring.

Prognosis

Prognosis of Bethlem Myopathy
Consult with your doctor.

Prevention

Prevention of Bethlem Myopathy
Consult with your doctor.