Geographic distribution of Kawasaki disease throughout Chile

Background: Incidence of Kawasaki disease (KD) in Chile is rising, however the distribution of cases throughout Chile is unknown. Objective: To describe the epidemiology of KD in Chile between years 2001 and 2011, and study the geographic distribution of KD cases throughout the country. Methods: We reviewed national hospital discharge databases for KD cases (ICD10 code M30.3) in children < 18 years. KD admission rates per 100,000 children < 5 years were calculated for every commune, health district and region, as a proxy of KD incidence. Results: 1,404 KD cases were registered with a national KD incidence rate of 8.7. KD incidence rate increased significantly from 5.9 in 2001-2003 to 10.4 in 2009-2011 (p < 0.001). Regions IX (Araucania), Metropolitan and VI (O'Higgins) had the highest KD incidence (12.4, 11.1 and 10.5 respectively), and regions III (Atacama), II (Antofagasta) and XII (Magallanes), had the lowest incidence (0.8, 3.9 and 4, respectively). The Eastern Metropolitan Health District, the population with the highest socioeconomic status in Chile, had the highest KD incidence rate (19.8) and concentrated 23.9% of the country's hospital discharges for KD. Conclusion: KD incidence in Chile is heterogeneous, with concentration of caseloads in the central regions and especially in the Eastern Metropolitan Health District. Geographic variations of KD in Chile could be associated with real differences in incidence or with disparities in diagnostic opportunity, and access to specialists and tertiary healthcare centers.