What is acne? Acne is a common skin condition that happens when hair follicles under the skin become clogged. Oil and dead skin cells plug the pores, and outbreaks of lesions (often called pimples or zits) can happen. Most often, the outbreaks occur on the face but can also appear on the back, chest, and shoulders. For most people, acne tends to go away by the time they reach their thirties, but some people in their forties and fifties continue to have this skin problem.
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 reactive arthritis? Reactive arthritis happens when an infection causes joint pain and swelling. A bacterial infection in the digestive or urinary tract or the genitals usually triggers the condition, but arthritis symptoms typically do not start until a few weeks after you have recovered from the infection. The most common features of reactive arthritis are inflammation of the joints (especially the knees and ankles), eyes, and urinary tract, but not everyone gets all three, or they might not happen at the same time.
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 epidermolysis bullosa? Epidermolysis bullosa is a group of rare diseases that cause fragile skin that leads to blisters and tearing. Tears, sores, and blisters in the skin happen when something rubs or bumps the skin. They can appear anywhere on the body. In severe cases, blisters may also develop inside the body. The symptoms of the disease usually begin at birth or during infancy and range from mild to severe.
What is fibrous dysplasia? Fibrous dysplasia happens when abnormal fibrous (scar-like) tissue replaces healthy bone. The fibrous tissue weakens the bone over time, which can lead to: Broken bones. Bones that are misshapen (bowed or crooked). The disease can affect any bone in the body. Some people have no symptoms or only a few symptoms. Other people may have more symptoms. Although there is no cure for fibrous dysplasia, treatments may help to lessen pain, and physical therapy may help strengthen muscle and improve movement.
What are autoinflammatory diseases? Autoinflammatory diseases refer to problems with the immune system, which usually fights off viruses, bacteria, and infection. The problem causes your immune cells to attack your body by mistake. This can cause swelling that produces fever, rash, joint swelling, or serious buildup of a blood protein in your organs.