A rare autoimmune disorder in which the immune system mistakenly attacks the muscles instead of viruses, bacteria, and other germs that can make you ill is called myositis. When it occurs, it is difficult to move or use the affected muscles. Unfortunately, there is no way to cure this disorder, but most of the time, you can put it into remission.
In other words, myositis is a condition that makes the immune system attack the muscles and causes chronic (long-term) inflammation. Over time, this condition causes your muscles to become weak and painful. Generally, myositis is a rare type of myopathy (a medical term used to describe disorders that negatively affect the skeletal muscles). In most cases, myositis affects muscles in the following parts of the body. For example:
- Legs
- Hips
- Arms
- Shoulders
- Spine
- Abdomen
In rare cases, myositis can affect the muscles on or near the eyes, esophagus, or diaphragm.
Types of Myositis
Physicians have divided this condition into 3 types based on the symptoms and the location of the affected muscles. For example:
Polymyositis
This type negatively affects several muscles at the same time. Commonly, people with polymyositis experience symptoms in muscles on or near the center of the body. Mostly, this type of myositis develops slowly over time and affects adults. Typically, females are more likely to develop this type of myositis compared to males. While it causes problems with certain muscles, people with polymyositis are often able to stand up after sitting, climb stairs, lift objects, and reach over their head.
Dermatomyositis
This type of myositis impacts the skin along with certain muscles. While the previous type of myositis may develop over months, dermatomyositis can develop quickly. That’s why it is very important to get treatment for dermatomyositis as soon as possible. In rare cases, this type of myositis can be fatal, especially in the first year. Moreover, dermatomyositis significantly increases the risk for certain cancers. When this condition affects children, it is called juvenile dermatomyositis.
Inclusion Body Myositis
This type of myositis is a degenerative muscle disease that usually happens in adults over 50 years old. Usually, it causes muscle weakness in the limbs (including the hands and legs). Approximately 30% of people with inclusion body myositis also develop dysphagia (swallowing problems). If you develop this type of myositis, it is often difficult to perform the following things. Examples include:
- Swallow
- Grip something small
- Walk or stand
- Use the hands and fingers to perform precise tasks
What Are The Symptoms of Myositis?
Usually, people who develop this condition experience the following symptoms. Examples include:
- Joint or muscle pain
- Swelling
- Extreme tiredness (fatigue)
- Difficult breathing or swallowing
- Arrhythmia (irregular heart rhythm), when the condition affects the heart muscle
- Muscle weakness
- Difficulty performing daily activities
Some people may experience additional symptoms, depending on the severity and type of myositis they develop. In any case, the appearance of any of the previous symptoms indicates a health problem. Therefore, you should visit a doctor for a diagnosis and treatment. Otherwise, it may lead to unpleasant outcomes.
Causes and Risk Factors
Healthcare professionals do not fully understand what exactly causes myositis. While it may happen on its own, sometimes it can be triggered by other disorders. Furthermore, doctors have identified some factors that may elevate your risk of developing myositis. Examples include:
- Scleroderma
- Rheumatoid arthritis
- Lupus
- Influenza (the flu)
- HIV infection
- The common cold
- Age – People between the ages of 35 and 64 are more likely to develop myositis.
- Sex – While dermatomyositis and polymyositis are more common in women, inclusion body myositis mostly affects men.
- Ethnicity – Some individuals of Sub-Saharan African descent are at higher risk of inflammatory myopathies compared to other ethnicities.
- Cancer – This condition is associated with some myositis subtypes.
- Genetics – A mutation (change) in the HLA 8.1 ancestral haplotype increases the risk of developing myositis.
- Medicines – People who are administering certain medicines for a long period are also at increased risk. These include statins (cholesterol medicines) and immune checkpoint inhibitors (cancer therapy).
- Environmental factors – These include long-term UV exposure, smoking, and vitamin D deficiency.
What Happens if Myositis is Left Untreated?
People who ignore the symptoms and do not get treatment in the early stages of the disease may experience some complications. Check some of them below:
- Interstitial lung disease (ILD) – It may cause inflammation and scarring (fibrosis) of the lung tissue, which negatively affects the respiratory system.
- Aspiration pneumonia – Usually, this complication occurs when a person inhales food or saliva into the lungs.
- Respiratory failure
- Myocarditis – This is a condition in which the heart muscle becomes inflamed. It may also lead to arrhythmia (irregular heart rhythm) and congestive heart failure.
- Heart disease (such as coronary artery disease)
- Dysphagia (difficulty swallowing)
- GERD (gastroesophageal reflux disease)
- Calcinosis (hard and painful calcium deposits that often form under the skin within the muscles)
- Joint contractures (reduced flexibility and stiffness)
- Raynaud’s phenomenon
- An increased risk for certain types of cancer
The previous list does not contain a full list of myositis complications. In any case, doctors may help you reduce the risk of experiencing them. Unfortunately, there is no way to prevent myositis because doctors do not know what exactly causes it.
Diagnosis
Like the diagnosis of many other health conditions, the diagnosis of myositis starts with a physical examination and questions about the symptoms and medical history. However, physicians may also perform some tests to confirm or exclude myositis. For example:
- Electromyography (EMG)
- MRI (magnetic resonance imaging)
- Blood tests
- Muscle biopsy – During this test, physicians will remove a small amount of the affected muscle for testing.
Treatment
The treatment goal is to put this condition into remission or relieve symptoms, prevent serious complications, and improve your quality of life. Most of the time, doctors prescribe the following options to treat myositis. For example:
- Corticosteroids (a group of medicines used to reduce inflammation)
- Immunosuppressants
- Intravenous (IV) immunoglobulin
- Physical therapy – This therapy is used to stretch the affected muscles and maintain them flexible and strong.
Frequently Asked Questions
When should I see my healthcare provider?
It is recommended to visit a doctor if you experience new muscle weakness, pain, or other symptoms that do not disappear within a few days. You should go to the nearest emergency room (ER) or call 911 if you cannot move a part of the body or cannot breathe or swallow.
What can I expect if I have myositis?
This autoimmune disorder cannot be cured, but sometimes treatment can put it into remission. However, people with myositis are at increased risk for rhabdomyolysis. Approximately 5% of people with dermatomyositis die within 1 year after the symptoms appear. That’s why early diagnosis and proper treatment are vital in people with this type of myositis.
What is the life expectancy with myositis?
Usually, the life expectancy of people with myositis is near-normal. In more severe cases, this condition can be fatal without immediate treatment.
Can myositis affect organs other than the muscles?
Although myositis primarily affects the muscles, it can also impact other organs and body systems. Some people develop lung problems, heart inflammation, swallowing difficulties, or skin changes, especially with dermatomyositis. The severity and extent of organ involvement vary from person to person.
Is myositis hereditary?
Most cases of myositis are not directly inherited from parents. However, certain genetic factors may increase the risk of developing autoimmune conditions, including myositis. Having a family history of autoimmune diseases may slightly increase your risk, but genetics alone usually do not cause the condition.
Can exercise help people with myositis?
Regular, low-impact exercise and physical therapy can help maintain muscle strength, flexibility, and overall function. These exercise programs should be tailored to each person’s condition and performed under the guidance of a healthcare professional to avoid overexertion.
Can children develop myositis?
Yes. Children can develop a form of the disease known as juvenile dermatomyositis. This condition causes muscle weakness and skin rashes and may affect growth and daily activities. Early diagnosis and treatment are important to reduce complications and improve long-term outcomes.
How long does it take to recover from myositis?
Recovery varies depending on the type of myositis, its severity, and how well a person responds to treatment. Some individuals achieve remission within months, while others require long-term treatment and monitoring. In certain cases, symptoms may come and go over time.
Are there foods that can help manage myositis symptoms?
While no specific diet can cure myositis, eating a balanced diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats may help support overall health and reduce inflammation. Your healthcare provider or a registered dietitian can recommend dietary changes based on your individual needs.
Can myositis return after remission?
Even after successful treatment and remission, myositis can sometimes relapse. Regular follow-up appointments and monitoring are important because early recognition of recurring symptoms allows doctors to adjust treatment and prevent disease progression. Ask your healthcare provider if you have any other questions.
