Myopathy

Myopathies are muscle diseases. In most cases, the striated skeletal muscles are affected. Muscular dystrophies or myotonic syndromes, for example, belong to the group of myopathies.

What are myopathies?

Muscle weakness is a characteristic symptom of all myopathies. With muscular dystrophies, in addition to progressive muscle weakness, muscle degeneration occurs.
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The term Myopathy comes from the Greek and means muscle pain. Accordingly, myopathies are diseases of the muscles. They usually affect the striated muscles of the skeleton. But also diseases of the heart muscle, the so-called cardiomyopathy, belong to the group of myopathies.

Myopathies are to be differentiated from other clinical pictures that are also associated with weakness of the muscles. For example, amyotrophic lateral sclerosis or spinal muscular atrophy are not myopathies. They belong to the diseases of the motor neuron. Myopathies can be divided into primary and secondary myopathies.

causes

Primary myopathies are primarily based on diseases of the muscles. So they are not based on any other disease. The muscular dystrophies belong to the degenerative primary myopathies. These include:

• girdle dystrophy,
• the facioscapulohumeral muscular dystrophy
• congenital muscular dystrophy.

Most muscular dystrophies are genetic. Myotonic syndromes such as myotonic dystrophy type 1, myotonic dystrophy type 2, Paramyotonia congenita Eulenburg or myotonia congenita Thomsen are also inherited. Congenital myopathies show up in newborns. Diseases such as nemalin myopathy, central core myopathy or myopathy with congenital fiber type disproportion are also caused by genetic defects.

The same is true for mitochondrial myopathies.Due to a [[[mutation]] in the DNA of the mitochondria, the mitochondria are reduced or changed. This leads to a disruption of the energy metabolism within the cell organelles. Myopathies also occur in the context of other underlying diseases. These muscle disorders are also known as secondary myopathies. Secondary myopathies are often the result of diseases of the endocrine system.

They occur in cases of hyperthyroidism or hyperthyroidism, Cushing's disease and diseases of the parathyroid gland (hypo- or hyperparathyroidism (overactive parathyroid gland)). Metabolic diseases can also make themselves felt through myopathies. The muscles need a lot of energy. Therefore, disorders of the energy metabolism manifest themselves in the muscles. Important diseases here are lipid storage disease or glycogen storage disease.

Myopathies can also result from a lack of nutrients. Muscle diseases occur with a vitamin D deficiency or with a selenium deficiency. Inflammatory myopathies arise from autoimmune diseases or infectious diseases. Trichinosis is an infectious disease that often results in myopathies. Autoimmune diseases with myopathies are polymyositis and inclusion body myositis, but myopathies can also be triggered by drugs, alcohol abuse, or other exogenous toxins.

Symptoms, ailments & signs

Muscle weakness is a characteristic symptom of all myopathies. With muscular dystrophies, in addition to progressive muscle weakness, muscle degeneration occurs. Congenital myopathies begin immediately after birth or in the first few months of life. The muscles develop too slowly or incompletely. The children cannot use their muscles against gravity.

Myotonic syndromes are characterized by a pathologically prolonged phase of tension in the muscles. Inflammatory myopathies are based on an inflammatory process. In addition to muscle weakness, the muscles become red and overheated. Pain is also possible. If the heart muscle is affected by the myopathy, the conduction of stimuli is impaired. The result is cardiac arrhythmias.

As a result of mitochondrial myopathy, brain function can be restricted. You may experience stroke-like symptoms. These phenomena are also known as MELAS syndrome. Mitochondrial myopathy is a multisystem disease. The eyes or inner ear can also be affected. Damage to the retina and optic nerve can lead to blindness. The development of diabetes mellitus is also favored by mitochondrial myopathy.

Diagnosis & course of disease

Muscle weakness as a characteristic syndrome provides the first indications of myopathy. In a detailed anamnesis, the doctor clarifies possible risk factors or causes. If a muscle disorder is suspected, a blood laboratory can be done. In muscular dystrophy, the creatine kinase (CK) in the blood serum is increased. This increases when skeletal muscle fibers break down.

The increase in creatine kinase in the blood is called hypercreatinemia. Aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT) and lactate dehydrogenase (LDH) are also elevated, but they are not as sensitive and specific as serum creatine kinase. The level of the creatine kinase value differs quite significantly between the individual muscular dystrophies. The value can therefore also be used for differential diagnosis.

A muscle biopsy is performed to confirm the diagnosis for most myopathies. Depending on the type of disease, different typical structures show up in the histological examination.

Complications

Myopathy primarily leads to severe muscle weakness. The resilience of those affected drops significantly and there are severe restrictions in everyday life. Those affected appear tired and exhausted from the illness and can no longer carry out normal everyday activities. It is not uncommon for myopathy to cause heart problems, which can lead to disturbances in the heart rhythm.

In the worst case, the affected person can also die of sudden cardiac death from this complaint. The symptoms in the heart continue to have a negative effect on the conduction of stimuli. In some cases, the myopathy leads to paralysis and further limitations in sensitivity. The motor skills can also be negatively affected by this disease. Those affected continue to suffer from diabetes not infrequently.

Treatment of myopathy can take place with the help of medication and through therapies and exercises. This can limit and reduce many complaints. As a rule, however, it cannot be predicted whether there will be complete healing. Complications can arise if a tumor has also developed. This may reduce the patient's life expectancy.

When should you go to the doctor?

A doctor should clarify a persistent general feeling of illness and internal weakness. If there are disorders of the metabolism or irregularities in the heart rhythm, a doctor should be visited to clarify the cause. Sleep disorders, poor concentration and attention, and a decrease in general performance should be examined and treated. In the case of increased energy requirements, rapid fatigue or lower resilience, there is a health impairment that should be clarified. If there are general dysfunctions, impaired vision or hearing, a doctor is required.

Internal irritation, sensory disturbances, numbness of the skin and hypersensitivity to temperature or touch should be discussed with a doctor. Inflammation of the muscles, an internal heat build-up, an increased need for fluids and headaches are signs of the organism for an existing disease. If there are interruptions in consciousness, muscle weakness or malaise, it is necessary to consult a doctor. Discoloration of the skin is a warning and should be presented to a doctor.

Palpitations, sleep disorders, restlessness and emotional abnormalities should also be discussed with a doctor. With changes in behavior, a depressed appearance or mood swings, sequelae can occur which must be taken into account when making a diagnosis. They can indirectly worsen an existing illness or trigger other disorders that should be treated.

Therapy & Treatment

The primary myopathies can usually not be treated causally because they are based on a genetic defect. Depending on the myopathy, different drugs are used to treat the symptoms. Physiotherapy can also help those affected. In the case of secondary myopathies, the treatment of the underlying disease is in the foreground. Hypothyroidism is treated with thyroid hormone preparations.

Anti-thyroid drugs are administered in the case of hyperthyroidism. Cushing's disease is treated with synthetic glucocorticoids. If Cushing's syndrome is caused by a tumor, it must of course be removed. In the case of nutritive myopathies, a substitution of the nutrient is necessary. Myopathy with cardiac involvement is usually treated with cardio-tonic drugs and antiarrhythmics.

You can find your medication here

➔ Medicines for muscle weakness

Outlook & forecast

Myopathy is unlikely to be fully cured until the years to come, when there are advances in genetics. With some forms of myopathy, the prospect of a cure is rather poor, as there are certainly fatal cases. This is especially the case with very young children and newborns who are born with congenital myopathy and other health disorders at the same time.

On the other hand, those with myopathies who show only minimal symptoms and who have a normal life expectancy. These minor myopathies do not progress and can also be managed well with today's modern treatment methods. Affected children also cope well with some forms of myopathy up to adulthood and often cope well into old age.

In particular, the life expectancy and quality of life of patients with congenital and non-congenital muscle wasting have improved in recent years. Life-threatening complaints are extremely rare and only occur in isolated cases. The majority of myopathies nowadays show an increasing number of recoveries and significant improvements in well-being, even if a cure is not always possible. The prognosis of myopathy is therefore extremely different and individual. In addition, the myopathies can so far only be treated causally or, depending on the type, only predominantly symptomatically.

prevention

Primary myopathies are inherited. Prevention is not possible here. Secondary myopathies can be prevented by early detection and treatment of the underlying disease. A sufficient supply of nutrients and vitamins such as vitamin D or selenium can reliably prevent nutritive myopathies.

Aftercare

In the case of myopathy, the measures or the possibilities of direct follow-up care are clearly limited in most cases. For this reason, the person affected should ideally consult a doctor at an early stage in order to prevent other complaints and complications from occurring. As a rule, it cannot heal independently, so treatment by a doctor is always necessary.

The earlier a doctor is consulted in the case of myopathy, the better the further course of the disease is usually, so that the early diagnosis is in the foreground. As a rule, patients with myopathy are dependent on the intake of various medications.

It is important to ensure the correct dosage and regular intake. Most of those affected depend on regular examinations and controls by a doctor so that further tumors can be detected at an early stage. The myopathy may result in a reduced life expectancy of the patient, with the further course very much depending on the exact severity of the disease.

You can do that yourself

For genetic myopathy, treatment can only alleviate symptoms and aim to improve quality of life. This includes regular participation in physiotherapy. Especially with water aerobics, very good results could be achieved in the area of ​​muscle building. A balanced diet and a healthy balance between stress and relaxation are generally supportive.

In the case of secondary myopathy, the underlying disease can be treated and the muscle weakness eliminated. Those affected should first check their consumption of drugs, alcohol and other stimulants. If there is a nutritional deficiency, this must be compensated for by those affected by targeted nutrition. Targeted nutrient therapy may also be used. The intake of selenium has been shown to help with this form of muscle weakness. Selenium is also recommended as a supplement to hormone intake if the thyroid is underactive. A healthy lifestyle with sufficient sleep, hydration and stress reduction (autogenic training, yoga) is fundamentally important, especially if you have an existing autoimmune disease.

Since myopathy is usually inherited and symptoms are already evident in toddlers, parents of affected children should seek advice at an early stage or seek support in a self-help group or psychological support. The emotional burden for those affected and their parents should not be underestimated. Affected families can also apply for household support from the statutory health insurance companies.