Myositis - Symptoms, Causes, Diagnosis & Treatment

According to the National Health Service (NHS), Myositis is a rare condition that causes weak muscles. It worsens with time, but early diagnosis and treatment may help ease the pain. Myositis emerges when the body's immune system mistakenly attacks its muscle tissues, leading to weakness, pain, and sometimes muscle damage. People experience difficulty in doing daily tasks and may notice skin rashes. The exact cause of myositis is not clear, but it is an autoimmune disorder. Infections and certain medications are responsible for myositis.

Sometimes diagnosing myositis is difficult, as its symptoms may overlap with other conditions. Your doctor will diagnose the symptoms, check the medical history, perform a physical examination, and recommend some blood tests, electromyography (EMG), and muscle biopsy to reach an accurate diagnosis. While myositis has no cure, treatment can improve symptoms and quality of life. 

Here in this blog, we will discuss myositis's symptoms, causes, and treatment options. Let's begin.

Types of Myositis

Myositis refers to a group of inflammatory muscle diseases that share the common feature of muscle inflammation. There are several types of myositis, each with distinct symptoms and clinical presentations. The main types of myositis include:

1. Dermatomyositis (DM): This type of myositis involves muscle inflammation, and skin rashes often appear on the face, neck, chest, elbows, knees, and back. 

Symptoms of Dermatomyositis are:

• Scaly, dry, or rough skin
• Fatigue
• Gottron's Papules
• difficulty swallowing
• muscle pain
• joint inflammation
• weight loss
• Abnormal heartbeat
• gastrointestinal ulcers

2. Polymyositis (PM): Polymyositis is caused by muscle inflammation and affects the proximal muscles, such as the shoulders, hips, thighs, and neck. 

Here are some common symptoms of PM:

• Muscle Weakness
• Difficulty with daily activities
• Muscle Pain or Tenderness

• Fatigue
• Dysphagia

• Speech Difficulties
• Difficulty in breathing
• Fever
• Weight Loss

3. Inclusion Body Myositis (IBM): This affects older adults and causes muscle weakness and atrophy, particularly in the muscles of the fingers, wrists, and quadriceps (front thigh muscles). 

Symptoms of IBM:

• Difficulty walking
• frequent falls
• difficulty swallowing
• muscle weakness
• muscle pain
• difficulty in rising after long sitting
• muscle weakness

4. Juvenile Myositis (JM) commonly affects children and adolescents. This causes muscle weakness and skin rashes. 

Symptoms of Juvenile myositis:

• Fatigue
• stomachaches
• trouble in lifting the head
• Swelling and redness of the skin
• muscle weakness
• Gottron's papules
• fever
• Muscle weakness
• difficulty in swelling
•  Muscle Pain or Tenderness

What are the common symptoms of Myositis?

The common symptoms seen in myositis patients are:

• Muscle Weakness: Usually, it affects both sides of the body, such as the muscles in the shoulders, hips, thighs, and neck. Climbing stairs, standing up from a seated position, or lifting objects may become challenging.

• Muscle Pain or Tenderness: The affected muscles may feel sore and tender to the touch. The pain can be mild to severe and may hinder everyday activities.
• Fatigue: Myositis can cause fatigue and weakness, even after minor physical exertion. 
• Difficulty Swallowing or Speaking (Dysphagia): In some cases, it affects the muscles used for speech, causing speech problems.
• Skin Rashes: Dermatomyositis, a specific type of myositis, causes skin rashes on the face, neck, chest, elbows, knees, and back.
• Joint Pain and Swelling: Some people may experience joint pain and swelling, similar to arthritis. 

What is the main cause of Myositis?

While the exact cause of myositis is unclear, researchers suggest it is an autoimmune disorder. Some factors that might increase the risk of the development of myositis include genetics, drug toxicity, and certain infections. 

• Autoimmune Diseases: The conditions like rheumatoid arthritis and lupus are examples of autoimmune diseases that may lead to myositis.
• Viral Infections: Infections caused by viruses such as the common cold, influenza (flu), and the human immunodeficiency virus (HIV) may sometimes trigger myositis.
• Drug Toxicity: Some drugs, particularly statins (cholesterol-lowering medications) and certain antibiotics, may cause side effects and lead to myositis.
• Genetic: Certain genetic factors may increase a person's susceptibility to developing myositis. There is evidence of a genetic component in some cases, as the condition may run in families.

What infections can cause myositis?

Myositis can be triggered due to viral, bacterial, or fungal infections. This disease affects the muscle tissue and causes inflammation in the muscles. Here are some conditions that are connected with Myositis infection: 

1. Viral Infections:

• Influenza (Flu) Virus
• Human Immunodeficiency Virus (HIV)
• Coxsackievirus
• Adenovirus
• Hepatitis B and C viruses
• Cytomegalovirus (CMV)
• Herpes Simplex Virus (HSV)

2. Bacterial Infections:

• Staphylococcus aureus (Staph infection)
• Streptococcus pyogenes (Strep throat)
• Borrelia burgdorferi (Lyme disease)

3. Parasitic Infections:

• Toxoplasma gondii (Toxoplasmosis)
• Trichinella spiralis (Trichinellosis)

What blood test confirms myositis?

Diagnosing myositis can be complex, as its symptoms can overlap with other health issues.  Thus, blood tests are essential to diagnose myositis. Here is some blood test that confirms the myositis:

• Creatine Kinase (CK) Test
• Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) Tests
• Myositis-Specific Autoantibodies Test
• Antinuclear Antibodies (ANA) Test
• Rheumatoid Factor (RF) Test
• Myositis-specific antibody panel blood test

Some other ways to diagnose myositis:

• Detailed medical history and physical examination.
• Electromyography (EMG) to evaluate muscle function.
• Muscle biopsy
• Magnetic resonance imaging (MRI)
• genetic testing
• nerve conduction study

If you are facing myositis symptoms, you should talk to your medical care experts for clinical evaluation, blood tests, imaging studies, and possibly a muscle biopsy for a definitive diagnosis. Choose Redcliffe Labs; the expert phlebotomist will provide you with accurate lab reports to identify the cause of symptoms that may be related to myositis. Early diagnosis and treatment can help to manage myositis effectively.

Prevention and Treatment of Myositis

While there is no cure for myositis, different treatment approaches can help manage the symptoms and improve quality of life. The treatment approach may include:

• Exercise: Regular exercise is beneficial to reduce myositis symptoms. 
• Rest: Adequate rest and pacing activities are essential for individuals with myositis, especially during disease flares or periods of increased muscle weakness and fatigue. 
• Nutritious Meal: A diet rich in fruits, vegetables, whole grains, and lean proteins provides essential nutrients for muscle health and overall well-being. 
• Reduce Stress: Stress can worsen symptoms and potentially trigger disease flares. Engage in relaxation techniques and mindfulness practices to manage stress levels.
• Physical therapy: An essential part of managing myositis, physical therapy helps maintain muscle strength and function.

The medication used in the treatment of myositis includes:

• Corticosteroids: These anti-inflammatory medications are often the first line of treatment to reduce muscle inflammation.
• Immunosuppressants: In more severe cases or when corticosteroids are insufficient, immunosuppressive drugs may be prescribed to control the immune system's response.
• Intravenous immunoglobulin: This is used to suppress the immune response, reduce muscle inflammation, and modulate autoantibodies.

Can myositis be cured?

Myositis is a rare but significant condition that affects the muscles, causing weakness and inflammation. Myositis patients may need a cane, walker, or wheelchair to walk. If this is not treated timely, it may lead to morbidity and even death. If you or someone you know experiences myositis symptoms, seeking medical attention is crucial. Get tested for Myositis and take proper treatment and medication to prevent severe complications.  With ongoing research and advancements in healthcare, the outlook for myositis patients continues to improve, offering hope for a better quality of life.