By Robert Bazell, NBC News Chief science correspondent
Tonight we begin a series called 'Medical Mysteries' about autoimmune diseases. We picked the title because these very common conditions remain incurable, difficult to treat, and poorly understood.
An autoimmune disease strikes when the exquisite system that protects our bodies from viruses and bacteria goes haywire. The white blood cells and the proteins called antibodies turn on us. The result can be damage to almost any organ in the body—chronic illness that can be severe and even life-threatening. The National Institutes of Health has a good primer on autoimmune diseases.