Coronary artery aneurysms are more severe in infants than in older children with Kawasaki disease

Objective We aimed to compare the severity of coronary artery abnormalities in Kawasaki disease between infants and older children. Methods We retrospectively reviewed and compared coronary artery dilation and aneurysm severity in infants < 1 year of age with Kawasaki disease at our centre over a 10-year period with that observed in children >= 1 year of age in the Pediatric Heart Network Trial of Pulse Steroid Therapy in Kawasaki Disease. Coronary artery abnormalities were defined by z-scores according to American Heart Association guidelines. Results Of the 93 infants identified during the study period, 80 were treated with intravenous gamma globulin within the first 10 days of illness and were included for comparison to 170 children >= 1 year of age treated in the same time frame from the Pediatric Heart Network public database. The mean maximum z-score was significantly higher in infants compared with older children (3.37 vs 2.07, p<0.001). A higher incidence of medium and giant aneurysms was observed in infants compared with children >= 1 year of age (11% vs 3% for medium aneurysms, p=0.015; 8% vs < 1% for giant aneurysms, p=0.005). Conclusions Infants with Kawasaki disease have more severe coronary artery dilation compared with older children, and a higher prevalence of medium and giant aneurysms. Because adverse outcomes are closely linked to the maximal coronary artery diameter in Kawasaki disease, patients diagnosed as infants require very close long-term monitoring for cardiac complications.