A case of rectal ulcers during aspirin therapy in acute Kawasaki disease.

Kawasaki disease (KD) is an acute febrile multisystem vasculitis and has been recognized to be one of the most common causes of acquired heart disease in children. Although gastrointestinal symptoms including vomiting, diarrhea, and abdominal pain are not uncommon in KD patients, KD with lower gastrointestinal bleeding is quite rare. Here, we describe a 3-year-old boy with typical KD who had lower gastrointestinal bleeding caused by rectal ulcers on the third day of aspirin therapy.