What Is Myositis? Know the Symptoms, Causes, Diagnosis, and Treatment Options

Myositis: Check out the types, causes, signs, symptoms, diagnosis and treatment.

Myositis is a slowly progressing rare autoimmune disease characterized by weak, painful and aching muscles. The meaning of myositis is muscle inflammation. Myositis is generally difficult to diagnose and there is no cure for this painful condition. However, people can be put into remission after they start getting treatment for Myositis.

Myositis is an autoimmune condition in which body's immune system becomes weak and starts targeting normal and healthy tissues. This disease can affect both adults and children, however there is only type of myositis called Polymyositis that specifically affects women.

According to Healthline, In the United States, there are an estimated 1,600 to 3,200 new cases per year and 50,000 to 75,000 people living with myositis.

Let us read about the types, signs, symptoms, diagnosis, and treatment of myositis in detail.

Types of Myositis and their Symptoms

According to Healthline, there are 5 types of myositis and following are the signs and symptoms associated with them.

1. Dermatomyositis: It is one of easily diagnosed forms of myositis due to its signs and symptoms. This type of myositis is generally found in women but may also affect children (juvenile dermatomyositis). People suffering from this condition develop purple-red coloured rashes on different parts of the body including - eyelids, face, neck, knuckles, back, chest, and toes. Following is the list of signs and symptoms of Dermatomyositis.

• Dry, rough, and scaly skin.

• Muscular pain

• Swallowing difficulties

• Raised, scaly and hard bumps found over the knucles, knees, and elbows called Gottron’s papules or Gottron’s signs.

• Joint inflammation

• Hoarse voice

• Heart arrhythmia (irregular heart beats).

• Abnormalities in nail bed.

• Weight loss.

2. Polymyositis: This type of myositis is commonly found in women between 30 to 60 years age. Neck, shoulder, back, hip, and thigh muscles are mainly affected by this condition. Following are the signs and symptoms of Polymyositis.

• Muscle weakness.

• Severe muscular pain and fatigue.

• Difficulty in raising your head.

• Problems in climbing stairs.

• Difficulty in getting up while you are seated.

• Breathing issues.

• Frequent falling.

• Depression and anxiety.

The symptoms get worse over time and may become extremely severe if not treated on time.

3. Juvenile Myositis: As the name indicates, this type of myositis is commonly found in children. Juvenile Myositis is twice as likely to occur in girls as it is in boys. It usually occurs in children who are under the age group of 18 years. Following are the signs and symptoms of Juvenile Myositis in children.

• Muscle pain

• Purple and red coloured rashes on different body parts especially elbows, knuckles, knees, and eyelids.

• Fatigue

• Irritability

• Mood changes

• Hoarse voice

• Fatigue

• Red and painful skin around nail beds

• Joint pain

• Weak muscles

• Gottron’s papules

• Dry and scaly skin

• Hard calcium lumps beneath skin

• Motor function abnormalities

4. Inclusion-Body Myositis: This type of myositis has a genetic cause and is generally found in men who are above the age of 50. Initially, the disease starts with the weakness in wrist, finger, and thigh muscles. This type of myositis is considered as asymmetrical because it predominantly affects one side of the body than other. Also, small muscles are mostly affected by this type of myositis. Here's the list of signs and symptoms of Inclusion-Body Myositis (IBM).

• Muscle pain and weakness.

• Fatigue

• Frequent falls

• Difficulty in hand gripping

• Body imbalance

• Decreased tendon reflexes

• Decreased hand and finger dexterity

• Difficulty in swallowing

5. Toxic Myositis: This is the rarest form among all types of myositis and is caused due to toxicity caused by consuming some prescribed and illicit medications. The signs and symptoms associated with this type of myositis are almost similar to the other types of the disease. This condition can be completely treated by stopping the drugs that caused it in the first place. Some of the drugs that may cause Toxic Myositis are:

• Statins (cholesterol controlling medicines)

• Cocaine

• Adalimumab (Humira).

• Immunosuppressant drugs

• Omeprazole (Prilosec)

What Are the Causes of Myositis?

The exact cause of myositis is still unknown. Since it is an autoimmune condition, the signs and symptoms are caused due to your body's immune system, which attacks the healthy tissues instead of protecting them. According to researchers, following are some of the conditions that may lead to myositis:

• Lupus erythematosus

• Rheumatoid arthritis

• HIV

• Drug-induced toxicity

• Scleroderma

How Myositis Can Be Diagnosed?

According to NHS UK, following are some of the diagnostic tests that might help your doctor in diagnosing myositis.

Common Blood Tests: Increased level of certain enzymes and antibodies in your blood may indicate myositis.

Tissue Biopsy: Taking skin or muscle tissue and examining it for any damage, swelling, and other changes via biopsy may also help in diagnosing myositis.

Magnetic Resonance Imaging (MRI): MRi scans can be used to visualize different body parts for any changes caused due to myositis.

Electromyography (EMG): This procedure can be performed to record and analyse the signals from nerve endings of muscles to diagnose myositis associated muscular damage.

How Myositis Can Be Treated?

There is no cure for myositis as of now. However, according to NHS, following are some of the treatment options for managing the symptoms of myositis and putting it into remission phase so that your routine life is not affected.

1. Exercise and physiotherapy to reduce muscle swelling and restore the strength of muscles.

2. Steroids to reduce muscular swelling and pain. These drugs are generally prescribed for treating polymyositis and dermatomyositis.

3. DMARD or Disease-modifying anti-rheumatic drugs like cyclophosphamide, mycophenolate, methotrexate, and azathioprine are prescribed to suppress the immune system and therefore help in reducing the inflammation.

4. Immunoglobulin therapy is given to patients with severe symptoms and helps in stopping the immune system from attacking the healthy tissues.

5. Biologic therapies like rituximab are given to patients with severe forms of myositis. These therapies reduce swelling and help in managing the underlying signs and symptoms of the disease.