What is alopecia areata? Alopecia areata is a disease that causes hair loss. In alopecia areata, the immune system attacks the structures in skin that form hair (hair follicles). Alopecia areata usually affects the head and face, though hair can be lost from any part of the body. Hair typically falls out in small, round patches about the size of a quarter. In some cases, hair loss is more extensive.
What is ankylosing spondylitis? Ankylosing spondylitis is a type of arthritis that causes inflammation in certain parts of the spine. Over time, this inflammation in the joints and tissues of the spine can cause stiffness. In severe cases, this may cause the bones in the spine to grow together, which can lead to a rigid spine that is difficult to bend. Many people with ankylosing spondylitis have mild episodes of back pain and stiffness that come and go. But others have severe, ongoing back pain and stiffness. Other symptoms also may develop if other areas of the body are affected
What is spinal stenosis? Spinal stenosis happens when the spaces in the spine narrow and create pressure on the spinal cord and nerve roots. The spinal cord is a bundle of nerves that comes out of the base of the brain and runs down the center of the spine. The nerve roots branch out from the cord. In spinal stenosis, the narrowing usually occurs over time.
What is vitiligo? Vitiligo is a chronic (long-lasting) disorder that causes areas of skin to lose color. When skin cells that make color are attacked and destroyed, the skin turns a milky-white color. No one knows what causes vitiligo, but it may be an autoimmune disease. In people with autoimmune diseases, the immune cells attack the body’s own healthy tissues by mistake, instead of viruses or bacteria. A person with vitiligo sometimes may have family members who also have the disease. There is no cure for vitiligo, but treatment may help skin tone appear more even.