Clinical Characteristics of Patients With Kawasaki Disease Whose Siblings Had the Same Disease

Background: Some patients with Kawasaki disease (KD) have siblings who developed the same disease. Using a large-scale epidemiologic dataset, the present study aimed to determine the clinical characteristics of this population. Methods: We analyzed 89,725 patients diagnosed with KD during 2011-2018 who were registered in the nationwide Japanese KD survey database. Multivariable logistic regression analyses were performed to determine factors associated with sibling history of KD. Results: Of the 89,725 patients, 1777 (2%) had sibling history of KD. Annual prevalence ranged from 1.5% to 2.3% during the study period and showed a tendency toward an increasing trend. Patients with recurrent KD and parental history of KD were significantly associated with sibling history of KD (adjusted odds ratio [95% confidence interval] = 2.15 [1.82-2.54] and 2.64 [2.02-3.47], respectively). Although patients with a sibling history of KD were significantly associated with initial intravenous immunoglobulin treatment resistance (1.14 [1.02-1.28]), no significant association was found between sibling history and coronary artery abnormality development. Among patients with a sibling history of KD, male patients were less likely to have recurrent KD than female patients (0.68 [0.49-0.96]). Conclusions: The significant association between sibling history and parental history may indicate genetic susceptibility to KD onset. Among those with a sibling history, recurrent KD was more likely to occur in female patients. Further studies focusing on this population may contribute toward identification of the cause of KD onset.