Maternal Autoimmune Disorders May Be Risk Factors for Kawasaki Disease in Children

The risk for Kawasaki disease is increased among children born to mothers with an autoimmune disorder, according to the results of a report published in The Journal of Pediatrics.¹

The early age of onset for Kawasaki disease suggests that pre- and perinatal exposures may be risk factors, including maternal autoimmune disorders that may share immune pathways with the disease.² Investigators explored the association between maternal autoimmune disorders and risk for Kawasaki disease in a retrospective, longitudinal cohort study of infants in Quebec, Canada between 2006 and 2016.

Data were collected for each child from the Maintenance and Use of Data for the Study of Hospital Clientele Registry that contained all hospitalization discharge summaries in Quebec; maternal autoimmune disorders were also identified from delivery discharge summaries and any other previous hospitalizations. Researchers explored data of exposure to any maternal autoimmune disorder and the number of disorders present. The primary outcome was hospitalization for Kawasaki disease among children aged between 0 and 12 years.

Of the 792,108 newborns (48.7% girls) included in the study, 13,239 (1.7%) were born to mothers with an autoimmune disorder and 779 (0.1%) were hospitalized for Kawasaki disease. The incidence of Kawasaki disease was higher among children born to mothers with an autoimmune disorder (21.8 per 100,000 person-years) compared with those who did not have an autoimmune disorder (14.1 per 100,000 person-years). The incidence was highest among children born to mothers with ≥2 autoimmune disorders (51.8 per 100,000 person-years; hazard ratio [HR], 3.69; 95% CI, 1.16-11.73). Results of the study showed that the presence of a maternal autoimmune disorder was associated with increased risk for Kawasaki disease in children (HR, 1.58; 95% CI, 1.39-1.79).

Compared with no maternal autoimmune disorder, the risk for childhood Kawasaki disease was highest in the presence of autoimmune thyroiditis (HR, 6.10; 95% CI, 5.48-6.80), followed by a rheumatologic disorder (HR, 1.84; 95% CI, 1.63-2.09), and traditional autoimmune disease (HR, 1.81; 95% CI, 1.59-2.04).

For most maternal autoimmune disorders, the strongest association with Kawasaki disease risk was observed in the first year of childhood. Among children aged 1 year, the risk for Kawasaki disease was 10.98-fold higher with maternal autoimmune thyroiditis, 2.57-fold higher with maternal traditional autoimmune disease, and 2.21-fold higher with maternal vasculitis compared with no maternal autoimmune disorder.

Researchers noted that the use of administrative hospital data may have limited the scope of their results as several autoimmune diseases were not observed at sufficient frequency in the data. In addition, information on ethnicity, paternal autoimmune disease, or immunosuppressive biologic therapy was not available.

“This longitudinal cohort study…found that maternal autoimmune disorders may be associated with the risk of Kawasaki disease in young children,” the researchers concluded. “The associations raise the question of whether Kawasaki disease may be genetically determined, although more research is needed to explore this pathway.”

With regard to the clinical implications of their work, the researchers also noted that “Kawasaki disease should be suspected in children with coronary vasculitis and a maternal history of autoimmune disorders.”

References

1. Belkaibech S, Potter BJ, Kang H, Lee GE, Bilodeau-Bertrand M, Auger N. Maternal autoimmune disorders and risk of Kawasaki disease in offspring [published online March 11, 2020]. J Pediatr. doi:10.1016/j.jpeds.2020.02.016

2. Hayward K, Wallace CA, Koepsell T. Perinatal exposures and Kawasaki disease in Washington State: a population based, case-control study. Pediatr Infect Dis J. 2012;31:1027-1031.