HSP is a condition that causes swelling and inflammation of small blood vessels. It occurs most often in children between ages 2 and 6.

Septic arthritis is an infection in the joint fluid (synovial fluid) and joint tissues. It occurs more often in children than in adults. Learn about causes, symptoms, diagnosis, and treatment.

Scleroderma is a rare, ongoing (chronic) disease. It causes abnormal growth of connective tissue. It can affect the joints, skin, and internal organs.

Rheumatic fever is a complex disease that affects the joints, skin, heart, blood vessels, and brain. It occurs mainly in children between ages 5 and 15.

Psoriatic arthritis is a rare form of arthritis. It affects both the skin and the joints.

JAS is a type of arthritis. It affects the spine and the places where the muscles, tendons, and ligaments attach to the bone.

Juvenile dermatomyositis is a rare disease that causes muscle inflammation and a skin rash. It's different from other muscle diseases because it also causes skin problems.

Fibromyalgia is a condition that causes pain in muscles and soft tissues around the body. The pain may be worse in the morning and evening.

Learn step-by-step how to give an emergency dose of naloxone nasal spray for an opioid overdose.

A vascular malformation is an abnormal growth of blood or lymph vessels. It doesn’t shrink over time. It continues to grow slowly during life.