Familial occurrence of Kawasaki syndrome in North America.

OBJECTIVE: To describe families with multiple members affected with Kawasaki syndrome (KS) to increase awareness of the familial occurrence of KS among practitioners who care for these patients.

DESIGN: Retrospective review of medical records at 2 medical centers and data collection from remote KS families who contacted the KS Research Program at the University of California, San Diego.

RESULTS: Eighteen families with multiple affected members were identified. There were 9 families with 2 affected siblings. In San Diego, 3 (0.7%) of 424 KS families had sibling cases. Nine families were identified with KS in 2 generations or in multiple affected members, yielding a total of 24 KS-affected children. No clear pattern of inheritance could be deduced from these pedigrees, and it is likely that multiple polymorphic alleles influence KS susceptibility.

CONCLUSION: Physicians should counsel affected families and make them aware of the potential increased risk of KS among family members.