Myositis is a group of inflammatory muscle diseases that cause muscle weakness and inflammation. There are several types of myositis, including polymyositis, dermatomyositis, and inclusion body myositis. Symptoms may include muscle weakness, fatigue, and difficulty climbing stairs or getting up from a seated position. Treatment typically involves the use of immunosuppressive medications, physical therapy, and exercise.
The exact cause of myositis is not known, but it is thought to be an autoimmune disorder. This means that the body’s immune system mistakenly attacks healthy tissue, in this case, the muscles. Some research suggests that certain genetic, environmental, or viral factors may play a role in the development of myositis. Certain medications or infections, such as HIV, may also increase the risk of developing myositis. However, the majority of myositis cases are considered idiopathic, meaning that the cause is unknown.
Symptoms of myositis vary depending on the type and severity of the condition, but they typically include muscle weakness and inflammation. Some common symptoms include:
- Progressive muscle weakness: This is the most common symptom and it may affect the proximal muscles (closer to the center of the body) such as shoulders, hips, neck, and back, making it hard to rise from a seated position, climb stairs, lift objects or even to comb hair.
- Fatigue: Many people with myositis experience severe fatigue, which may be caused by muscle weakness and inflammation.
- Pain: muscle pain is common in myositis.
- Difficulty swallowing: Some people with myositis experience difficulty swallowing, which may be caused by weakness of the muscles used in swallowing.
- Skin rash: Some types of myositis are associated with a characteristic skin rash, such as a purplish rash on the eyelids, cheeks, and around the mouth in dermatomyositis.
- Weight loss: Some people may lose weight due to muscle weakness and lack of appetite.
- Fever: Some people may experience fever and other flu-like symptoms.
Treatment for myositis depends on the type and severity of the condition, but it typically involves a combination of immunosuppressive medications, physical therapy, and exercise. The goal of treatment is to reduce inflammation and muscle weakness and to prevent further muscle damage.
- Medications: The most common medications used to treat myositis are corticosteroids such as prednisone which are used to suppress inflammation and reduce muscle weakness. Other immunosuppressive drugs such as methotrexate, azathioprine, and mycophenolate may also be used.
- Physical therapy: Physical therapy can help to improve muscle strength and flexibility, and prevent muscle atrophy.
- Exercise: Exercise can help to improve muscle strength and endurance, and is an important part of treatment.
- Other therapies: Occupational therapy may be helpful in some cases, to assist with activities of daily living.
In some cases, the treatment may require a multidisciplinary approach, involving rheumatologists, physical therapists, occupational therapists, pulmonologists, and other specialists.
Myositis can be a serious condition and in rare cases, it can be fatal. The severity of the disease and the risk of complications depend on the type of myositis, the extent of muscle involvement, and the overall health of the individual.
The most severe forms of myositis are polymyositis and dermatomyositis, these can lead to respiratory failure and weakness of the diaphragm muscle, which can be fatal if not treated promptly.
Inclusion body myositis is a less severe form of the disease, but it tends to be chronic and progressive, leading to a decline in muscle strength over time.
Patients with myositis, who have lung involvement, have a higher risk of complications and death. The risk of complications and death is also increased in older adults and those who have other underlying health conditions.
Is myositis curable?
Myositis is a chronic condition, which means that it is not currently curable. However, with appropriate treatment and management, the symptoms can be controlled and the progression of the disease can be slowed.
The treatment for myositis typically involves a combination of immunosuppressive medications, physical therapy, and exercise. These treatments can help to reduce inflammation, improve muscle strength and function, and prevent further muscle damage.
It is important to note that treatment for myositis may take time and that it may take several months to see improvement in symptoms. In some cases, myositis may become chronic and require long-term treatment. The majority of myositis patients respond well to treatment, and the prognosis is generally good.
how is myositis diagnosed?
Myositis is typically diagnosed through a combination of medical history, physical examination, blood tests, and imaging studies. Blood tests may include a complete blood count, creatine kinase level, and aldolase level. Imaging studies such as an MRI or ultrasound may also be used to help diagnose myositis and to evaluate the extent of muscle inflammation and damage. In some cases, a muscle biopsy may be necessary to confirm the diagnosis. The diagnosis may also be supported by the presence of characteristic symptoms such as muscle weakness, stiffness, and pain.