The Bethlem myopathy is a very rare genetic disease associated with muscle weakness and wasting, but also functional and restricted movement of the joints.
What is Bethlem Myopathy?
Bethlem myopathy was first described in 1976 by scientists J. Bethlem and GK Wijngaarden. That is why it got its name in 1988. It is a very rare disease, to date only just under 100 cases have been documented.
Bethlem myopathy is caused by a genetic defect. If one of the three genes responsible for collagen VI (COL6 A1, COL6 A2 or COL6 A3) mutates, the metabolism in the mitochondria does not function properly. If these energy providers for the muscles do not work properly, the muscle tissue is gradually converted into connective tissue and this process is unstoppable and progressively destroys the muscles.
Those who carry the genetic defect inevitably get the disease and their children inherit the genetic defect with a probability of 50 percent. Scientists speak of an autosomal dominant inheritance here. In most cases the disease occurs in the newborn age, but sometimes it occurs much later. There are also different degrees and courses of the disease.
Symptoms, ailments & signs
If the disease occurs very early, it can first be recognized by a delayed motor development, a general reduction in movement and, in particular, a restricted movement of the fingers, wrists, elbows and ankles.
Shortened muscles and tendons mean that the fingers and toes cannot be moved properly, the elbows and sometimes the knees cannot be properly straightened. In some cases the joints are hypermobile and can be overstretched. In addition, there is often a bad temperature balance. The affected children freeze very quickly and excessively.
Symptoms are similar in the adult patient. In addition, there is a progressive stiffening of the spine, arthrosis of the joints, and the muscles quickly become fatigued. For example, those affected have difficulty climbing stairs and have difficulty stretching their arms above their heads.
Wounds heal poorly, scars appear bulging, and indigestion can occur. In many cases, the lung function is also disturbed in adult patients because tendons in the spine can be shortened in the area of the upper body.
Often the complexion is also bad. Not everyone struggles with the same symptoms. For some, the mobility restrictions are more pronounced, for others, the muscle weakness is the greater problem.
Diagnosis & course
Bethlem myopathy is very difficult to diagnose because the symptoms are common to many different conditions and the disease is so rare. There are many sufferers who take years to find the real cause of their suffering.
However, the family history should provide good information, precisely because Bethlem myopathy is a hereditary disease and occurs in families. Imaging methods such as x-rays, MRI and electromyography cannot give a clear result. Even a muscle biopsy only works to a limited extent. Only a genetic test can provide final certainty about the genetic defect. With increasing age, the disease becomes more and more noticeable, also because there are various secondary diseases.
Bethlem myopathy has various complications, but most of them affect the muscles. Joints can also be affected by Bethlem myopathy. The disease can occur in childhood or in adulthood. It is not possible to predict the onset of Bethlem myopathy.
In young children, all movements are severely restricted by Bethlem myopathy. Above all, this includes the movements of the fingers and joints. The patient’s everyday life is severely restricted and the quality of life decreases. In children, Bethlem myopathy can lead to bullying, which can result in depression and thoughts of suicide.
In some cases, patients rely on the help of strangers to cope with everyday life. Adults experience similar symptoms, but the muscles get tired more quickly. Climbing stairs is hardly possible anymore, so that there are severe restrictions in movement.
Bethlem myopathy slows the healing of wounds. This can lead to infections and inflammation. The lungs are also affected by this inflammation. The skin of those affected is impure, pimples and redness often appear, which are associated with itching. Treatment is only possible through physiotherapy, which does not always lead to a positive course of the disease.
When should you go to the doctor?
Bethlem myopathy can be identified by a few distinct symptoms. If there is restricted movement of the fingers, wrists, elbows and ankles, this should be clarified by a doctor. Parents who notice delayed motor development or a general lack of movement in their child should consult their pediatrician. An immediate doctor’s visit is required if there are severe restrictions on movement of the fingers and toes.
In adults, progressive stiffening of the spine and rapid fatigue of the muscles indicate bethlem myopathy or some other disease that must be clarified and treated immediately. In addition, wound healing is impaired and the pulmonary and digestive tracts are disturbed.
In particular, if the family has hereditary diseases, you should see a doctor quickly with the symptoms mentioned. A genetic test provides information about the causal disease and enables comprehensive therapy. If the disease is left untreated, the symptoms increase in intensity over the course of life and ultimately lead to a sharp decrease in quality of life.
Treatment & Therapy
To date, there is no cure for Bethlem myopathy. Medicines for the underlying disease are not available, surgical interventions are also not very promising due to the progression of the disorders and are therefore only carried out in exceptional cases. However, there are a number of things that people can do to alleviate the symptoms associated with the disease and to delay complications and worsening.
For example, stretching exercises are helpful to keep the muscles as supple as possible and to prevent tension. Warmth and a good balance between activity and rest are also good. Obese people should try to reach normal weight.
This is also good for the muscles and joints. Weight training and excessive strain on the muscles are to be avoided at all costs. On the other hand, it is important that patients do everything to stay active and flexible for as long as possible. Special physiotherapy and occupational therapy measures have a positive effect.
Sports that are gentle on the joints and muscles are primarily swimming, light water aerobics, bicycle ergometers or treadmills, as long as those affected can still do them. Of course, you still have to avoid falling or overloading your joints. When the disease is advanced, the patients then need aids to cope with their everyday lives.
These can be orthoses that support the affected limbs, walking aids, rollators, bathtub lifts, raised toilet seats or wheelchairs. There are also various smaller practical helpers that are helpful in everyday life. The assortment ranges from gripping aids, special knives and scissors to shoe and stocking pullers to special cutlery. In extreme cases, affected patients even have to be ventilated if the respiratory muscles are particularly badly affected.
Outlook & forecast
Bethlem myopathy has an unfavorable prognosis. The cause of the disease is an irreparable genetic defect that cannot be cured with the latest scientific and medical methods. In addition, for legal reasons, an intervention and thus a change in human genetics is not permitted.
The disease has a progressive course in which the symptoms gradually spread unabated over several years. In the last phase, it is no longer possible for the person affected to cope with his or her own everyday life without sufficient help. The patient is supported medically and therapeutically in alleviating the accompanying symptoms so that he can achieve the best possible quality of life despite the illness. So far, however, there has been no recovery from Bethlem myopathy.
Successful efforts take place in delaying progress. Targeted training and exercise units to maintain the muscles are used. The focus is on stretching and training on how to achieve optimal movement sequences despite the restrictions. The patient can carry out many of the training units they have learned on their own in everyday life and also receives medically trained support that adapts to the ever-changing individual circumstances.
Those affected increase their wellbeing through sporting activities and a healthy lifestyle. In addition, by taking advantage of psychotherapeutic support, he can optimally cope with the challenges in everyday life.
There are no preventive measures for Bethlem myopathy. However, it is important to recognize the hereditary disease as quickly as possible and to care for those affected as well as possible. You need comprehensive interdisciplinary medical care from the very beginning, where neurologists, orthopedists, pulmonologists and specialists in internal medicine work together.
But psychosocial advice is just as important. Self-help groups are also highly recommended. The better those affected know about the disease, the better they can deal with it and the higher their quality of life will be.
You can do that yourself
Bethlem myopathy shows different courses in terms of severity and progression of symptoms. Because the autosomal dominant inherited disease is extremely rare, the first symptoms are often misinterpreted and assigned to another disease. If symptoms appear in early childhood, they are usually motor development disorders and restricted mobility. Adaptive behavior in everyday life can be important for the further course of the disease.
Since no therapies are known to date that could stop or even cure Bethlem myopathy, psychosocial care is important. That is why it is important to be connected to a self-help group. Those affected can exchange ideas and receive attention. Muscular stretching exercises are recommended, which should be supervised by physiotherapy, but which the sick can also do themselves.
It is mainly about maintaining the functionality of the muscles and the mobility of the joints as long as possible. In the course of the disease, muscle cells are increasingly replaced by connective tissue cells, so that the muscles lose their elasticity and strength. Recommended sports are, for example, swimming, light water aerobics and bicycle ergometers. Excessive strain on the muscles and joints should be avoided.
If the illness progresses, self-help also consists of setting up technical aids within the apartment. These can be, for example, entry aids for the bathtub, stair lifts, raised toilet seats and many other practical precautions that are individually tailored to the patient.