Atypical manifestations of cardiomegaly and nephrotic syndrome in Kawasaki disease

Rationale: To examine atypical manifestations of Kawasaki disease (KD) in children. Background: Cardiovascular complications during acute KD are a major contributor to its mortality rate. It can involve the pericardium, the myocardium, the endocardium, and/or the coronary arteries; however, cardiomegaly and nephrotic syndrome (NS) during the acute stage of KD have seldom been reported. Patient concerns: Two children, each with a fever lasting more than 5 days, were diagnosed with cardiomegaly using echocardiography in the early phase of Kawasaki disease (within 2 weeks). Case 1 was misdiagnosed with NS because of the proteinuria, hypoalbuminemia, and edema present at the onset of the disease. Diagnoses: A diagnosis of incomplete KD was based on a constellation of clinical manifestations and symptoms and was supported by laboratory results. Interventions: Intravenous immunoglobulin (IVIG) and aspirin were administered, supplemented with and without supplemental steroid therapy (case dependent). Outcomes: The clinical manifestations and syndromes of the two cases were completely resolved and their heart size restored to normal within 2 weeks, with no evidence of coronary artery lesions (CAL). Main lessons: Physical findings and manifestations are atypical in incomplete KD. Cardiomegaly and nephrotic syndrome can be an early manifestation of KD; cardiomegaly, especially, should be recognized as a possible manifestation of the acute stage of KD. Furthermore, these symptoms can be rapidly relieved by treatment with IVIG, with or without supplemental steroid therapy.