Polymyositis (muscle inflammation)

Description A rare disorder tha...

Description

A rare disorder that causes muscle weakness and pain. The cause is not known but is felt to be an autoimmune disease which means the patient's immune system becomes over active and attacks the muscles causing inflammation of the muscle fibers. The muscles of the upper legs often are affected first causing problems climbing stairs and getting out of a chair. This disease can be very serious, causing breathing problems, abnormal beating of the heart, heart failure, and difficulty swallowing. Polymyositis usually affects people between the ages of 30 and 60, and some patients can have other autoimmune diseases such as lupus.

Symptoms

The symptoms may be gradual or rapid in onset, and may increase and decrease with time. Patients experience muscle weakness, fatigue, pain, problems swallowing, heart palpitations, and breathing difficulties.

Tests

Common tests used for diagnosis and treatment

Workup:
A history and physical will be performed. Blood tests such as a creatine kinase and imaging tests will be done. Studies to evaluate the muscles such as an electromyograph (EMG) and a muscle biopsy may be performed. Tests for special antibodies (autoantibodies) may be performed, to determine if the body is attacking itself.

Tests:
Complete blood count (CBC), Comprehensive metabolic panel (CMP), Electromyography (EMG), Magnetic resonance imaging (MRI)

Other Specific Tests: Muscle biopsy

Specialists:
Internal Medicine, Rheumatology, Neurology, Pediatric Neurology, Pediatric Rheumatology

Treatment

Therapy depends on the severity of the symptoms. Patients are encouraged to exercise and use physical therapy to decrease the stiffness and improve mobility. Medications are used to decrease the inflammation and they include steroids and immunosuppressive drugs. Intravenous immunoglobulin therapy may also be used.