Polymyositis is a rare disease characterized by muscle inflammation whose causes 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.
What is polymyositis?
Polymyositis is a disease that belongs to the family of idiopathic inflammatory myopathies , or myositis. In other words, it corresponds to an inflammatory muscular disease whose precise origin is still unknown to this day. Characterized by muscle inflammation, this disease can affect many muscles.
What is the cause of polymyositis?
Although the precise cause of polymyositis is not known , several hypotheses have been made by the researchers. It seems that there are genetic predispositions to this disease. In genetically predisposed individuals, 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.
Who is concerned ?
Although it represents between 10 to 20% of myositis cases, polymyositis is a rare disease . The prevalence of polymyositis is 6 to 7 cases per 100 000 people, with an estimated annual incidence between 5 and 10 new cases per million inhabitants.
With a few exceptions, polymyositis is a pathology that affects adults only . It is more common among women , with a proportion of 2 women to 1 man.
What is the evolution of polymyositis?
Polymyositis usually develops gradually , from weeks to months. It can sometimes be associated with other pathologies such as tumoral conditions, autoimmune diseases or viral infections.
What are the symptoms of polymyositis?
Polymyositis is a disease characterized by muscle inflammation that can occur in many muscles. It can notably manifest itself in the muscles of the musculoskeletal system, the respiratory system and the ENT sphere.
When it affects the muscles of the musculoskeletal system, polymyositis is usually manifested by:
- a weakness that occurs in the proximal muscles of the arms, shoulders and thighs;
- Muscle pain, also called myalgia.
This weakness and muscle pain complicates many gestures of daily life. Nevertheless, these symptoms are not constant. Their occurrence is quite random according to the people.
When it affects the respiratory system, polymyositis can be manifested by several symptoms including:
- a cough ;
- fever ;
- A difficulty breathing , also called dyspnea.
When it occurs in the ENT sphere, polymyositis particularly affects the pharyngeal muscles . The polymysosite is then manifested by:
- swallowing disorders;
- nasal regurgitation;
- a cough while eating;
- a hoarseness of the voice;
- A nasal voice.
How to treat polymyositis?
Treatment of polymyositis is usually based on medication and physiotherapy.
The drug treatment of polymyositis is based on immunomodulators. In first intention, treatment with corticosteroids (corticosteroids) is put in place. It is effective in 60 to 70% of cases. If resistance, intolerance or dependence on corticosteroids is observed, another treatment based immunosuppressants can be proposed.
The treatment of polymyositis is also based on physiotherapy through re-education and rehabilitation sessions.