The Most Common Causes of Baker’s Cysts

9. Lupus

Another autoimmune disease, systemic lupus erythematosus causes the body’s immune system to attack healthy tissue. Symptoms vary wildly from person to person and can be mild or severe, leading to difficulties in diagnosis. The most common symptoms are pain, fatigue, and joint inflammation. The latter can be severe and lead to cysts. Women old enough to have children are nine times more likely than men to be affected by lupus -- those between 15 and 45 years old are most often affected.

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