What is Polymyositis?
Polymyositis is a rare inflammatory muscle disease that causes muscle weakness and inflammation, primarily affecting the skeletal muscles closest to the trunk, such as those in the hips, thighs, shoulders, and neck. It is an autoimmune condition, meaning the body’s immune system mistakenly attacks its own muscle tissues. Polymyositis can develop gradually and may impact mobility and daily activities.
What causes Polymyositis?
The exact cause of polymyositis is unknown, but it is believed to involve an autoimmune response triggered by:
- Genetic predisposition
- Viral or bacterial infections that may initiate the immune attack
- Environmental factors
- Possible association with other autoimmune diseases
What are the symptoms of Polymyositis?
Symptoms often develop over weeks to months and include:
- Progressive muscle weakness, especially in the hips, thighs, shoulders, and upper arms
- Difficulty rising from a seated position, climbing stairs, or lifting objects
- Muscle pain or tenderness (less common)
- Fatigue and general weakness
- Difficulty swallowing or breathing in severe cases
- Joint pain or inflammation in some individuals
- Possible skin rash if associated with dermatomyositis (a related condition)
How is Polymyositis diagnosed?
Diagnosis involves a combination of clinical evaluation and tests, including:
- Physical examination to assess muscle strength
- Blood tests measuring muscle enzymes (like creatine kinase) that increase with muscle damage
- Electromyography (EMG) to detect abnormal muscle electrical activity
- Muscle biopsy to confirm inflammation and muscle tissue damage
- Imaging studies such as MRI to detect muscle inflammation
- Autoantibody tests to identify autoimmune markers
What are the treatment options for Polymyositis?
Treatment aims to reduce inflammation, improve muscle strength, and manage symptoms:
- Corticosteroids (like prednisone) to suppress immune system activity
- Immunosuppressive drugs such as methotrexate or azathioprine if steroids are insufficient or cause side effects
- Physical therapy to maintain and improve muscle strength and flexibility
- Intravenous immunoglobulin (IVIG) therapy in severe or resistant cases
- Treatment of complications such as difficulty swallowing or breathing
What is the recovery and prognosis for Polymyositis?
- Early diagnosis and treatment improve outcomes significantly
- Many patients experience partial or full recovery of muscle strength
- Some may have a chronic course with relapses and remissions
- Severe cases with respiratory or swallowing involvement may require specialized care
- Regular follow-up is important to monitor disease activity and adjust treatment
How can Polymyositis be prevented or managed long-term?
- There is no known way to prevent polymyositis
- Long-term management includes adherence to treatment and physical therapy
- Regular monitoring for side effects of medications and disease progression
- Lifestyle modifications such as balanced nutrition and avoiding infections
- Support groups and counseling may help cope with chronic illness