Polymyositis is a rare disease characterized by muscle inflammation the causes of which are unknown to date. It can affect many muscles in the body, including those of the musculoskeletal system, the respiratory system and the ENT sphere.

Polymyositis is a disease that is part of the family of myopathies idiopathic inflammatory, or myositis. In other words, it corresponds to an inflammatory muscle disease the precise origin of which remains unknown to this day. Characterized by muscle inflammation, this disease can affect many muscles.

Although the precise cause of polymyositis is not not known, several hypotheses have been put forward by the researchers. It would seem that there are genetic predispositions to this disease. In genetically predisposed people, the onset of polymyositis would be influenced by certain environmental factors. A chronic immune response is thought to be responsible for the muscle inflammation characteristic of polymyositis.

Although it represents between 10 to 20% of cases of myositis, polymyositis is a rare sickness. The prevalence of polymyositis is 6 to 7 cases per 100 people, with an estimated annual incidence of 000 to 5 new cases per million inhabitants.

With a few exceptions, polymyositis is a pathology that affects exclusively adults. It is more common in women, with a proportion of 2 women for 1 man.

Polymyositis usually has a progressive development, between several weeks and several months. It can sometimes be found associated with other pathologies such as tumor conditions, autoimmune diseases or viral infections.

Polymyositis is a disease characterized by muscle inflammation that can occur in many muscles. It can manifest itself in particular in the muscles of the musculoskeletal system, the respiratory system and the ENT sphere.

When it affects the muscles of the musculoskeletal system, polymyositis usually manifests itself as:

• muscle weakness, which occurs in the proximal muscles of the arms, shoulders and thighs;
• muscle pain, also called myalgia.

This weakness and muscle pain complicate many everyday activities. However, these symptoms are not constant. Their occurrence is quite random depending on the person.

When it affects the respiratory system, polymyositis can manifest itself by several symptoms including:

• a cough ;
• fever ;
• difficulty in breathing, also called dyspnea.

When it occurs in the ENT sphere, polymyositis particularly affects the muscles of the pharynx. Polymysositis then manifests itself by:

• swallowing disorders;
• nasal regurgitation;
• a cough while eating;
• hoarseness of the voice;
• a nasal voice.

Treatment of polymyositis is usually based on drug therapy and physiotherapy sessions.

Drug treatment for polymyositis is based on immunomodulators. As a first-line treatment, corticosteroids (corticosteroid therapy) are set up. This is effective in 60 to 70% of cases. If resistance, intolerance or dependence on corticosteroids is observed, another treatment with immunosuppressants may be offered.

The treatment of polymyositis is also based on physiotherapy through rehabilitation and rehabilitation sessions.