Changes in the Clinical Characteristics of Kawasaki Disease After Coronavirus Disease (COVID-19) Pandemic: A Database Analysis

Abstract

Background The impact of the coronavirus disease 2019 (COVID-19) pandemic on Kawasaki disease (KD) has not yet been established. We investigated changes in the observed number and severity of KD cases and accompanying coronary artery complications during the COVID-19 pandemic in Korea. Methods This retrospective observational study included patients aged < 18 years with acute-phase KD diagnosed between March 2018 and February 2021. Data were extracted from the Clinical Data Warehouse that houses data from five affiliated university hospitals in Korea. We analyzed changes in the number of patient admissions and clinical characteristics, including cardiac complications, before and after the onset of the COVID-19 pandemic. Results A total of 475 admissions were included in the analysis. After March 2020, we observed a significant decrease of 33% in the number of hospitalizations for KD compared with the average number of hospitalizations during the previous 2 years. The number of admissions per month significantly decreased by 7.9 persons/month (95% confidence interval, −13.8 to −2.0; P < 0.05) compared with that before COVID-19. By contrast, the proportion of patients aged < 1 year with KD increased. The proportion of patients with refractory KD and the rate of cardiac complications did not change significantly. Conclusion Since the onset of the COVID-19 pandemic, the total number of hospital admissions for KD has decreased in Korea. Although the proportion of admissions of infants aged < 1 year increased, no changes were observed in clinical courses and complications.

Decreased incidence of Kawasaki disease in South Korea during the SARS-CoV-2 pandemic

“…Specifically, we observed that the incidence rate in children aged <1 year was high compared with that in the other age groups, with a significant increase from the values in the previous years. This result is consistent with those of previous studies conducted in the United States and Japan and domestic multicenter studies ( 11 , 25 ). As expected, the social behavior of children under 1 year of age is unlikely to have changed significantly between the pre-pandemic and pandemic periods.…”

Factors linked to Kawasaki disease and MIS-C in children with prolonged fever: A retrospective cohort study

“…As reported by Kim et al [29], even though there was an increase in the proportion of infants under 1 year of age hospitalized for KD, the prevalence of refractory KD and challenging cases did not significantly increase during social distancing. While MIS-C and KD exhibit marked inflammation and inflammatory vasculopathy, further research is essential to ascertain whether these conditions represent distinct immunopathogenic disorders [30].…”

Emerging Insights Into the Pathophysiology of Multisystem Inflammatory Syndrome Associated With COVID-19 in Children

“… 53 , 78 It is possible that some of the decrease in KD may be related to misclassification of KD patients as having MIS-C, although this is more likely related to decrease exposure to possible infectious/environmental triggers. 79 , 80 A case series from Korea, where the incidence of MIS-C during the pandemic has been very low, compared 19 KD patients with a history of prior COVID-19 with 26 KD patients without, and noted few differences, although patients with prior COVID were older with more severe disease, which may suggest some similiarities with MIS-C. 81 The association of prior COVID-19 and vaccination with the risk of subsequent KD is largely unknown. In contrast, a report from Seattle noted that patients with a prior history of KD did not have adverse outcomes when either infected with SARS-CoV-2 or vaccinated with mRNA COVID-19 vaccines.…”