Selena Gomez's grandfather has confirmed that the pop star is being treated for lupus. Lupus is an autoimmune disease in which the body's immune system attacks normal, healthy tissue, for still mysterious reasons. It can be life-threatening. Selena has been working non stop with touring, recording, and doing movies that she is exhausted and that has aggravated her condition. She is currently receiving treatment. - Read More On Selena's Condition