Abstract
BACKGROUND: Kawasaki disease (KD) is a systemic vasculitis that primarily affects children. Adult-onset KD is rare and often under-recognized, leading to delayed diagnosis and severe complications. CASE SUMMARY: A previously healthy 19-year-old man was admitted with fever and mucocutaneous symptoms and required intensive care for hypotension that developed during hospitalization. Thereafter, rapidly enlarging coronary artery aneurysms were identified, leading to a suspicion of KD. Five months after onset, coronary angiography revealed critical stenoses, and myocardial perfusion imaging revealed ischemia. The patient underwent off-pump coronary artery bypass grafting, and the postoperative course was uneventful. DISCUSSION: Few reports have described adult-onset KD with such extensive coronary involvement requiring bypass surgery. This case highlights the diagnostic challenges associated with adult-onset KD and strongly advocates early diagnosis. Advanced imaging enables timely surgical intervention. TAKE-HOME MESSAGES: KD can present with life-threatening coronary sequelae in adults. Early diagnosis and close imaging surveillance can prevent coronary complications.