Dermatomyositis

Synonyms

Polymyositis, Lila disease

definition

In the Dermatomyositis is it a inflammatory diseases of the skin and skeletal muscles.

Also can organs such as the kidney or the liver to be affected. Dermatomyositis is also called purple disease, as it is primarily caused by a purple reddening in the area of ​​the Eyelids notices.

Frequency distribution

With dermatomyositis one differentiates two phases in which the disease occurs.

For one thing, it can be in Child ages between five and 14 years occur. Approximately 0.2 / 100,000 inhabitants / year fall ill.

More often However, the disease occurs between the 35 and 65 years of age on, here mostly as a result of or before a tumor disease. 0.6-1.0 / 100,000 inhabitants / year fall ill.

Thus, dermatomyositis is one very rare disease, in which Women more often are affected as men. Most diseases manifest themselves in women by the age of 50, usually with a predisposition to tumor diseases.

causes

The exact cause (etiology) of the disease is not yet clear. It is believed to be a immunological disease acts. This means that the body forms autoantibodies directed against an endogenous structure.

In dermatomyositis, the body forms Autoantibodies against a certain structure that is in skin and bone is located, namely that Collagen. The collagen is a protein found in our connective tissue occurs and ensures that our Skin elastic yet mechanically stressable is. At the same time, it ensures a large one in the bone stability and yet for a certain Flexibility. In addition to the skin and bones, collagen is also found in the Tooth structure, in cartilage, in Tendons and in different bands. The collagen is thus a "universal protein" with many different subtypes that fulfill their characteristic function in the respective tissue. In the tendons, for example, collagen is arranged in parallel and therefore has an enormous tensile force. The collagen is cross-linked in the skin to ensure a high level of elasticity.

Since in dermatomyositis antibodies are directed against components of the collagen, one also speaks of one Collagenosis. It is believed that psychological stress, one genetic predisposition such as Exposure to sunlight support the development of such a collagenosis. Since collagen is found in every connective tissue and in every organ, too every organ affected be. However, there are also cases that are limited to the muscles or the skin. If just the muscle is affected and no other organ or connective tissue, one speaks of one Polymyositis.

It is important to know that dermatomyositis mostly with a tumor, i.e. a neoplasm, goes hand in hand. In women there are often cancers in the area of Ovaries (Ovarian cancer). It is not clear whether the cancer is the cause of the dermatomyositis or whether the dermatomyositis develops first and then a cancer develops. Although the exact cause is not clear, one should always get tested for a possible cancer if a dermatomyositis is present.

It is different with children who develop dermatomyositis. This is often a virus-induced disease that is almost always associated with muscle weakness. The viruses (presumably Coxsackiviruses) trigger an autoimmunization, i.e. a defense reaction of the body against the body's own collagen components.

Symptoms

The Symptoms dermatomyositis very different fail. There are, however characteristic Symptoms that can be seen in most patients.

It usually comes first to the classic purple color in the area of ​​the eyelid; this typical skin changes, especially in Area of ​​the eyelids and trunk occurring is through a Erythema caused, mostly with a Swelling (edema) goes hand in hand. An erythema arises there Blood vessels, so the Veins and Arteries, themselves expand and it becomes one Increased blood flow comes in this skin area. In addition to the swelling and redness, there is also a Decrease in skin thickness (atrophy of the epidermis). This decrease occurs particularly in the Area of ​​the extensor joints of the finger instead of. There is also one Change in fingernails, since you are now in this area the small Recognize blood vessels (capillaries) can. This is a Telangiectasia.

The patient also has a permanent weakness in the muscles being especially proximal muscles are affected, i.e. the muscles in Shoulder and hip area. For example, it is difficult for the patient to lift their arm properly. In addition to muscle weakness, it can also be Muscular pain come, similar to the pain of sore muscles.

Another, but unnoticed, symptom is that Vasculitis. This is a Inflammation of blood vessels. It can be too fever, Night sweats and Exhaustion come.

More symptoms can arise as soon as an organ, such as the liver, the kidney, the heart, the lung or that too Central nervous system are affected. For example, if the lungs are affected, there may be a difficult breathing (dyspnoea) come. Due to the Muscle weakness it can also become a sad-looking facial expression come (Hypomimia).

In one very late stage settle down Calcium phosphate plaques on the skin a (Calcinosis cutis).

diagnosis

The diagnosis Dermatomyositis is mostly due to the recognizable Symptoms posed. A patient suffers Reduced strength, Muscle aches, fever and one visible reddening of the skin (febrile erythema), so it is very likely a dermatomyositis.

Additionally will blood removed and analyzed in the laboratory. With the laboratory values ​​one then falls Increase in liver enzymes (transaminases), of the Apoproteins, of the LDH (Lactate dehydrogenase), the enzyme Aldolase and the Creatine kinase on. Additionally are antinuclear antibodies, which are directed against components of the cell nucleus, detectable.

In the histological examination also occurs Recession of the skin (atrophy of the epidermis) on. There is also one Basal cell degeneration, this means that the lowest cell layer of the skin is no longer properly recognizable because the cells perish. in the Electromyogram is also a Inflammation of the muscles (myositis) recognizable.

Where is dermatomyositis common?

Dermatomyositis on the face

The symptoms of dermatomyositis on the skin are particularly noticeable in areas that are most exposed to sunlight.

In addition to the hands, this also includes that face, in which dark red to blue-violet (lilac) Skin discoloration (Erythema) can attract attention.
These are often found in the skin area around the eyes (periorbital), in the cheek area, on the bridge of the nose, but also on the cleavage, the back and the arms.

The discoloration of the skin can - especially often on the eyelids - be accompanied by slight or severe swelling, itchy or even burn and pain. If the cheek area is affected, a whitish, thin rim around the mouth is usually noticeable, which is spared from the skin discoloration (perioral border, „Shawl sign“).

In addition to the characteristic discoloration of the skin, a change in facial features may also be noticeable, which is caused by the skin change. Often one develops reduced facial expressions (Hypomimia), from which a typical, sad expression can result.

Dermatomyositis on the hands

To the areas of the body where Skin changes can occur as part of an existing dermatomyositis, in addition to the face, décolleté, back and arms, especially the hands.

On the extensor sides of the fingers, i.e. the top of the fingers (not the palm side), redness can occur - as in the face - possibly also from small protrusions or reddish, flat skin nodules (Papules) to be accompanied (Grotton’s symbol).

These so-called Grotton's papules are often found above the finger joints, but in some cases can also extend or spread to the back of the hand.

This reddening of the skin and papules on the fingers can be with itching or even painful and burning sensations are associated.

Furthermore, the nail line and the cuticle can thicken, whereby pushing back the cuticle or touching the nail line can also be painful (No sign).

In rare cases, painful reduced blood flow in the hands can occur every now and then, often triggered by cold water or cold outside temperatures (Renaud’s seizures).

therapy

In the therapy a dermatomyositis, it depends on whether in addition to the disease additionally a carcinoma occured. Most of the time it comes through Removal of the tumor to a decline illness.

The patient suffers exclusively on dermatomyositis he should be first Keep away from strong UV light radiation. In addition, Glucocorticoids treated that the Counteract inflammation should. Is the disease already far advanced or it is a serious case, should the patient further Immunosuppressants take in. These are drugs that do this Suppress the immune system, because this wrongly in case of illness attacks the body's own cells. If you suppress the immune system, you can minimize the wrong immune response. In addition to immunosuppressants, you can also Cytostatics be used.

Mostly should few weeks after therapy the Symptoms much better become. In addition to drug therapy, a physical therapy be carried out around the gradually build up weakened muscles again.

prophylaxis

Since the exact causes dermatomyositis to this day not clear it is difficult to prevent the disease. However, it is believed that psychological stress and high UV radiation (for example by exposure to sunlight or by frequent visits to the solarium) promote the disease. It is therefore important to reduce the number of visits to the solarium to a minimum, especially if the family has already suffered similar illnesses.

forecast

The forecast which is dermatomyositis bad. Within the first 2 years die 30% of all patients, many due to the tumor disease; if this is adequately treated, the dermatomyositis can also regress successfully, so that life expectancy increases enormously.

Because of the therapy with Immunosuppressants Many patients die of harmless infections because the immune system is no longer able to control them.

Course of dermatomyositis

Dermatomyositis is one of the diseases that cannot yet be cured, so treatment is only one Symptom relief and a Improving the quality of life cause and pursue as a goal.

Because it is a disease from the autoimmune Therapy usually consists of suppressing the immune system, i.e. suppressing it, in order to prevent the wrong reaction of the immune system with the body's own structures (mostly with glucocorticoids / cortisone or immunosuppressants).

However, this therapy must be carried out consistently over a long period of time, a recurrence of the symptoms during or after the therapy as well as a worsening of symptoms can never be 100% excluded.

The course of dermatomyositis depends heavily on whether it occurs as part of a tumorous disease or as an independent disease and cannot therefore be predicted across the board. It has been shown that adequate drug treatment can at least significantly reduce the symptoms of the disease.