Kawasaki Disease

A rare inflammation of the arteries, Kawasaki Disease affects roughly 19 out of every 100,000 kids in the U.S., mostly those under 5. Backstreet Boy Brian Littrell's son was just recently diagnosed with it, and it's apparently what Jett Travolta died from.

Wikipedia sez: "Kawasaki disease is a poorly understood self-limited vasculitis that affects many organs, including the skin and mucous membranes, lymph nodes, blood vessel walls, and the heart." It's named for the doctor who first discovered it. Also: It's best that you DO NOT do a Google Image search for this disease.