KS causes more than 5,000 hospitalizations per year in
the US.6 Approximately 75%-85% of cases occur in
children younger than 5 years, and boys are more often
affected than girls at an estimated ratio of 1.5:1.1,6 Seasonally,
KS peaks in most geographic areas during the
winter and early spring.1 The etiologic agent of KS
remains unknown.1,5 Research attempting to link the
illness to drugs or environmental exposures, such as
carpet cleaner or humidifiers, has been unsuccessful.