Kawasaki disease in a five-month-old infant

Abstract

Introduction:  Kawasaki disease, an acute self-limited vasculitis of small and medium arteries of unknown etiology, is the leading cause of heart disease in children in most developed countries. If untreated, it can lead to coronary artery dilatation and aneurysm, placing patients at risk for coronary thrombosis, myocardial infarction, or sudden death.

Case Report: A previously healthy five-month-old boy presented with a history of respiratory symptoms and fever, being admitted for respiratory syncytial virus bronchiolitis. He maintained fever for five days associated with progressive clinical worsening and sequential development of conjunctival injection, cracked lips, swelling of hands and feet, and polymorphous rash of the limbs. Diagnostic procedures showed increased levels of inflammatory markers, hyponatremia, hypoalbuminemia, sterile pyuria, and aseptic meningitis. Despite an initial normal echocardiogram, Kawasaki disease was suspected and the boy started intravenous immunoglobulin on the fifth day. On the seventh day, echocardiogram showed signs of pancarditis and mild coronary artery ectasia and acetylsalicylic acid was started. The boy was discharged, but eight days later echocardiogram revealed major and diffuse coronary artery ectasia in a follow-up consultation and he was readmitted to start corticosteroid therapy. After five months, the boy displayed normalization of cardiac changes, without further complications.

Comments: Kawasaki disease below six months of age is rare and associated with a high risk of coronary artery aneurysm. It is important to recognize the clinical and laboratory criteria associated with this entity and start early treatment, avoiding cardiac complications.