Emery-Dreifuss muscular dystrophy is a hereditary disease that develops based on a mutation and is associated with muscle weakness and wasting. Two forms of the disease with different modes of inheritance are known to date. Therapeutic measures mainly include physiotherapy.
What is Emery-Dreifuss muscular dystrophy?
The disease group of muscular dystrophies includes a number of progressive muscle diseases that can be classified as hereditary diseases and arise on the basis of a mutation in the genetic material. Muscular dystrophies are usually caused by a defect or deficiency of muscle proteins. The result is muscle weakness, which later causes muscle atrophy. The changes in muscle tissue progress progressively and are also called dystrophic changes. One disease from the group of muscular dystrophies is Emery-Dreifuss muscular dystrophy. The disease was first described as an independent muscular dystrophy around the middle of the 20th century. The name Hauptmann-Thannhauser syndrome is used as a synonym for the hereditary disease. Two different forms of the disease exist, both of which are hereditary and differ only in the localization of the affected genes and the respective mode of inheritance. Like all muscular dystrophies, Emery-Dreifuss muscular dystrophy is associated with genetic mutations. The AD-EDMD mode of inheritance was documented by Hauptmann and Thannhauser as early as 1941. Emery and Dreifuss described the X-linked form of the disease in 1966.
Causes
Emery-Dreifuss muscular dystrophy does not occur sporadically. Instead, a familial clustering has been observed in association with the disease, which speaks to the genetic basis and heritability of the muscle disease. The two heritable forms of the disease differ according to the localization of the genes involved. Both forms are based on a mutation. However, they are not the same mutation. The first form of muscular dystrophy is caused by a mutation of the coding gene for the nuclear protein emerin. The corresponding gene is located at gene locus Xq28. This form of the disease is also known as X-linked EDMD and is passed in X-linked inheritance. The complete loss of emerin seems to be causative for the patients’ muscle weakness. However, the correlations are unclear so far. The second form is caused by mutations of the LMNA gene, which is located on gene locus 1q21 and is involved in the coding of the nuclear structural proteins lamin A/C. Mutation of this gene initiates the autosomal dominant inherited form of the disease, also known as AD-EDMD. In this form of the disease, an incorrectly assembled motor end plate is present on the muscles due to the mutation. Which external factors, in addition to genetic factors, play a role in the onset of the disease has not yet been conclusively determined.
Symptoms, complaints, and signs
Patients with Emery-Dreifuss muscular dystrophy suffer from a complex of clinical symptoms, all of which affect the muscles and progress progressively. Therefore, although the disease is congenital, the symptoms may not be apparent immediately after birth. Often they are barely noticeable at first and are only recognized through progression. This progression progresses rather slowly. In most cases, the individual symptoms appear at a relatively young age. However, symptomless cases into young adulthood may also occur. There are three main symptoms or abnormalities that are indicative of the disease. Most patients are affected by a shortening of the Achilles tendons and additionally of the elbow muscles. For this reason, they are usually unable to fully extend the leg or arm. The second characteristic symptom is progressive muscle weakness, which can manifest itself in clumsiness or physically reduced performance, among other things. Often, the progressive weakness of the muscles is accompanied by concomitant wear and tear of the muscles, eventually leading to muscle wasting. A later consequence of Emery-Dreifuss anomaly may be dilated cardiac vessels, specifically affecting the right atrium.
Diagnosis
A suspected diagnosis of Emery-Dreifuss muscular dystrophy is made on the basis of history, exercise testing, and laboratory diagnosis. Laboratory diagnostics reveal an elevation of creatine kinase. Movement tests show muscle weakness with symptoms such as gait instability.Electromyography can be performed to confirm the diagnosis, providing evidence of dilated cardiac components. In addition, muscle histology can be performed, which usually confirms muscle necrosis or phagocytosis of necrotic muscle cells. Early detection of the disease is prognostically favorable.
Complications
In Emery-Dreifuss muscular dystrophy, affected individuals are primarily affected by muscle wasting and generalized muscle weakness. It is thus impossible for the patient to perform physical activities or various sports. Everyday life is considerably restricted by Emery-Dreifuss muscular dystrophy. In many cases, only a delayed diagnosis occurs because the disease does not manifest itself immediately after birth. This can complicate treatment and lead to further complications. In rare cases, symptoms do not appear until adulthood. Patients often suffer from malformations and abnormalities of the muscles and extremities. This manifests itself primarily in a greatly reduced performance capacity and in restricted motor skills. Patients often appear clumsy and are unable to do certain things in everyday life without outside help. Progressive Emery-Dreifuss muscular dystrophy eventually leads to muscle atrophy, which can severely restrict the patient’s everyday life. Causative treatment is not possible for Emery-Dreifuss muscular dystrophy. For this reason, only the symptoms can be treated. In this way, life expectancy can be kept constant. As a rule, regular examinations are necessary for the patient to ensure that no further complications occur.
When should one go to the doctor?
A visit to the doctor is necessary as soon as problems with the musculature develop. If decreased strength or physical performance occurs for no apparent reason, this is considered unusual. A visit to the doctor is necessary so that a comprehensive examination can clarify the cause. In many cases, there is a gradual reduction in muscle strength. A visit to the doctor should be made as soon as the changes in everyday life are consciously noticed. If cramps, pain or an unexplained loss of muscle strength occur, these complaints should be examined and treated by a doctor. Before taking muscle-building supplements, consult a physician to clarify risks and side effects in advance. If usual physical obligations at work or in private life can no longer be fulfilled, a visit to the doctor is necessary. If there is a sudden and persistent lack of the necessary performance during usual sporting activities, this should be discussed with a doctor. If there is emotional impairment due to the complaints, a doctor should be consulted. If there are behavioral problems, a social withdrawal, apathy, a diminished sense of well-being, or a depressed mood, there is cause for concern. Working with a physician or therapist, relief can be achieved.
Treatment and therapy
Causal therapy does not exist for patients with Emery-Dreifuss muscular dystrophy. Treatment is purely symptomatic and supportive. In conservative therapy, patients adapt their lifestyle to the disease. Henceforth, affected individuals must avoid, as far as possible, sports activities that could deform the muscle. Not all sports activities have an unfavorable effect on sufferers. In physiotherapy, patients learn about beneficial sports activities. The goal of these treatment steps is to maintain mobility and combat muscle atrophy through targeted muscle loading. The earlier the patient’s disease is detected, the more likely it is that cardiac defects can be prevented. Close monitoring by the cardiologist is indicated to observe any cardiac manifestations. Causal treatments for Emery-Dreifuss muscular dystrophy patients may become available in the near future. Gene therapy approaches to muscular dystrophy are currently an area of research. However, these approaches are not currently in the clinical phase. In addition to gene therapy, the use of adenoviral vectors to introduce emery-like equivalents is likely to make the disease a curable condition in the near future.
Outlook and prognosis
Emery-Dreifuss muscular dystrophy is a disease of the genetic disease family.The mutation of a gene thus triggers the symptoms. For legal reasons, physicians and scientists are not allowed to interfere with the genetics of humans in order to make changes, according to the current status. As a result, there is currently no cure for the disease. The symptoms are treated symptomatically. Since the course of the disease is progressive despite all efforts, the prognosis of the disease is described as unfavorable. The efforts of the physicians are focused on the promotion of the muscles. In targeted therapies, exercises and training are worked out that result in support of the muscular system. Everyday life and especially the choice of sports activities are restricted for the patient. The way of life has to be adapted to the physical requirements so that no excessive demands occur. The later the disease is discovered and treated, the less improvement in impairments is possible. Complications can arise that lead to a worsening of the prognosis. Nevertheless, medical care of the patient will maintain the average life expectancy. Because of the mental and emotional stresses associated with Emery-Dreifuss muscular dystrophy, secondary diseases and psychological disorders may develop. Such a development worsens the patient’s overall prognosis to a significant degree.
Prevention
To date, no preventive measures are available for Emery-Dreifuss muscular dystrophy except for molecular genetic analysis to detect familial predispositions.
Here’s what you can do yourself
Emery-Dreifuss muscular dystrophy patients can plan to build up their muscles independently and on their own responsibility in addition to medical care. Regular sports activities and a well-developed workout help to counteract the degradation of the musculature as far as the disease allows. In addition, a healthy and balanced diet helps. The patient’s musculature can be specifically supported by the choice of food and meals. With the intake of a lot of protein, the building of the muscles is promoted. The intake of many fats and or harmful substances should be avoided at the same time. The consumption of nicotine or alcohol has a detrimental effect on health and worsens the general well-being. In order to maintain mobility for a long time, it is necessary to adapt the exercise routines to the available possibilities. In all life situations, certain exercises can be incorporated that help to improve the conditions and at the same time have a preventive effect. The muscles should also be well and sufficiently supported by an adequate supply of heat. Exposure to cold or drafts should be avoided. In addition to the physical offerings, mental strengthening is helpful. To reduce stress, methods of relaxation help. Inner pressure is thereby reduced and composure is trained in dealing with the challenges of everyday life.
