Kawasaki disease in Latvia 2012-2019: epidemiology and rate of resistance to initial treatment.

Introduction: Kawasaki disease (KD) is an acute febrile illness of early childhood, characterised by vasculitis of the coronary and medium-sized arteries. The incidence of the disease differs worldwide, but the incidence of KD has not been established in Latvia. The aim of the study was to describe the epidemiological characteristics and estimate the incidence rate and resistance to initial treatment of KD among hospitalised children in Latvia. Material and methods: The study was a descriptive, population-based study, which used hospital discharge records of patients < 18 years old diagnosed with KD in the years 2012-2019. Incidence rate was calculated using the number of KD patients and corresponding national census data. Results: There were 36 KD patients in Latvia. The median age at admission was 2.8 years, with 67% of cases under 5 years of age, and the male/female ratio was 1.3 : 1. The mean annual incidence rate was 1.3 per 100,000 children 0-18 years old, and 2.9 per 100,000 for children < 5 years old. The mean length of hospital stay was 14 days. Coronary artery dilatation was recorded in 8% of the patients (all of whom were male). Every patient received intravenous immunoglobulin (IVIG), with a median of 7 days from fever onset to IVIG administration. Refractory treatment was reported in 25% of cases. Conclusions: This is the first epidemiological study of KD in Latvia. The incidence rates are lower than those reported for other European countries. The percentage of refractory treatment was higher than in other studies.