Dermatomyositis is an inflammation of the striated muscles (myositis) involving the skin and internal organs such as kidneys, lungs and heart. In this rheumatoid inflammatory autoimmune disease, the body's own immune system attacks parts of the muscles and skin. However, if only the muscles are affected, this is referred to as polymyositis.
The reasons for this disease are still unclear. The disease often occurs in connection with a malignant tumour. To what extent a genetic disposition is decisive for the outbreak of the disease or pathogen (such as viruses, bacteria or toxoplasms) is just as unclear as whether disturbances of the cell-mediated immune reaction or autoantibodies can trigger the disease.
Dermamyositis is a rare disease that can occur at almost any age and affects more women than men. There are two age phases in which most new diseases are recorded:
1. In childhood (Juvenile Dermamyositis)
2. In middle age between 45 and 60 years of age
The disease usually occurs insidiously within 3 to 6 months. In addition to general signs of the disease such as fatigue, weight loss and fever, there are cases of rhabdomyolysis, dissolution of the striated muscles or myoglonimuria, i.e. increased excretion of myoglobin via the urine due to injuries of the striated muscles.
Both forms of the disease cause muscle weakness of the large thigh and upper arm/shoulder muscles. The swallowing apparatus and other muscle groups can also be affected. In the case of dermatomyositis, the disease can also manifest itself in a lilac reddening of the skin. Preferably in body parts that are frequently exposed to the sun, such as eyelids, bridge of nose, cheeks, décolleté and the extensor sides of the hands.
Due to the rarity of the disease, there are no standard therapies available so far. Therefore, an individual plan must always be drawn up for drug treatment.
In case of new muscle weakness or skin changes described above, a rheumatologist or neurologist should be consulted immediately.