Parents with a history of Kawasaki disease whose child also had the same disease.

BACKGROUND

The aim of this study was to describe time trends of prevalence and detailed characteristics of parents with a history of Kawasaki disease (KD) who had a child with the same disease using data from Japanese nationwide surveys on KD.

METHODS

Parents with a history of KD were identified using nationwide surveys of KD patients who visited hospitals between 1999 and 2008. To confirm KD histories, a parental questionnaire was sent to pediatricians who reported parental cases to the surveys for KD patients who visited hospitals from 2001 through 2004. Parental history was ascertained by merging data from the parental questionnaire with data from previous nationwide surveys, and detailed information about childhood KD was obtained from survey reports.

RESULTS

During the 10-year study period, 407 parents with a child with KD were reported as having a KD history (0.43%). The prevalence of such parents significantly increased during this study period (regression coefficient: 0.13, 95% confidence interval: 0.05-0.20). Thirty-one confirmed parents with the history were diagnosed between 1966 and 1984. All parents met the case definition of KD, and 33% had been treated with steroids. No parent with a KD history received intravenous immunoglobulin (IVIG).

CONCLUSIONS

The prevalence of parents with KD history with a child with the same disease increased during the study period. Some of these parents had not been treated with IVIG because they were diagnosed before its use was widespread in Japan. An increase in the number of parents with the history is expected, thus continuous monitoring of familial cases with KD is required.