[Kawasaki disease in infants under one year of age. A challenge for the diagnosis and treatment of patients. Experience in a hospital center in Mexico].

Background: Frequency of Kawasaki disease (KD) in infants is low in almost all countries. These patients are at higher risk of developing cardiac complications.

Aim: To evaluate the clinical features, treatment used and cardiac outcome in infants under one year of age attending for KD in a third level pediatric hospital in Mexico City, Mexico.

Methods: A cross-sectional study was conducted in our hospital from August 1995 to August 2019. We analyzed the clinical features, laboratory results, treatment used and cardiac outcomes in infants younger than one year of age and compared them with older patients.

Results: We included 687 patients, 152 were younger than one year of age (22.1%). There was a delayed diagnosis in younger patients with an increased frequency of incomplete clinical presentations. Coronary artery abnormalities were most common in younger infants who also had an increased frequency of giant coronary artery aneurysms. Two patients in the younger group died in the acute phase of KD of myocardial infarction.

Conclusions: Diagnosis of KD in infants younger than 1 year of age is a clinical challenge with an increased rate of incomplete clinical presentations and also an increased risk of development of severe cardiac complications.