Diseases

Polymyositis

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An autoimmune inflammatory disease of muscle that begins when white blood cells spontaneously invade muscles, especially those closest to the trunk or torso. This immune activity results in muscle pain, tenderness, and weakness.

SYMPTOMS

The muscle weakness associated with polymyositis involves the muscles closest to the trunk, such as those in your hips, thighs, shoulders, upper arms and neck. The weakness affects both the left and right sides of your body, and tends to gradually worsen.

CAUSES

The exact cause of polymyositis is unknown, but the disease shares many characteristics with autoimmune disorders, in which your immune system mistakenly attacks your own body tissues.