Can kawasaki disease cause death in a young child if not treated?

Yes. Kawasaki's disease is a very serious condition that can cause some serious complications such as a coronary artery aneurysm. These aneurysms can clot causing a heart attack or rupture and both of these can cause death. Your pediatrician should hospitalize your child and treat immediately with ivig (immunoglobulins), and that can decrease the risk of this very serious complication.