Kawasaki Disease Hospitalizations in the United States 2016–2020: A Comparison of Before and During the Coronavirus Disease 2019 Era

Abstract

Background: Kawasaki disease (KD) is an acute vasculitis of young children. A comparison of US hospitalization rates and epidemiologic features of KD in 2020 to those of precoronavirus disease years has yet to be reported. Methods: Using a large, inpatient database, we conducted a retrospective cohort study and analyzed data for patients with (1) diagnosis coding for KD, (2) IV immunoglobulin treatment administered during hospitalization and (3) discharge date between January 1, 2016, and December 30, 2020. Severe cases were defined as those requiring adjunctive therapy or IV immunoglobulin–resistant therapy. Results: The annual number of KD hospitalizations were stable from 2016 to 2019 (n = 1652, 1796, 1748, 1692, respectively) but decreased in 2020 (n = 1383). KD hospitalizations demonstrated seasonal variation with an annual peak between December and April. A second peak of KD admissions was observed in May 2020. The proportion of KD cases classified as severe increased to 40% in 2020 from 33% during the years 2016–2019 ( P < 0.01). Median age in years increased from 2.9 in subjects hospitalized from 2016 to 2019 to 3.2 in 2020 ( P = 0.002). Conclusions: Compared with the previous 4 years, the annual number of pediatric KD admissions decreased, and children discharged with diagnostic codes for KD in 2020 were generally older and more likely to have severe morbidity possibly reflective of misdiagnosed multisystem inflammatory syndrome in children. Clinicians should be wary of a possible rise in KD rates in the postcoronavirus disease 2019 era as social distancing policies are lifted and other viruses associated with KD return.

Efficacy of Glucocorticoid plus Intravenous Immunoglobulin in Children with Immunoglobulin-Insensitive Kawasaki Disease

“…KD is a self-limiting systemic vasculitis that can cause multiorgan arteritis, resulting in impaired multiple organ function [ 17 ]. Its incidence rate is still increasing, especially among men and children of Asian races [ 18 ]. This study mainly discusses the clinical effects of GC and IVIG in Ig-insensitive KD, aiming at contributing to the treatment of the disease.…”

Epidemiological and Clinical Features of Kawasaki Disease During the COVID-19 Pandemic in the United States

“…Recent reports from around the world have revealed significant reductions in KD incidence during 2020. 2 , 3 , 4 , 5 , 6 , 7 , 8 …”

Number of Kawasaki Disease Admissions Is Associated with Number of Domestic COVID-19 and Severe Enterovirus Case Numbers in Taiwan

“…However, a peak in KD admissions occurred in May of 2020 immediately after the initial wave of COVID-19 infections in the United States. Within this study, of the 1383 patients diagnosed with KD in 2020, 108 (8%) were also positive for COVID-19 infection [ 18 ]. In Paris, France, a single-center retrospective study recorded a marked increase of KD cases beginning two weeks after the first wave of COVID-19 infections in the country; eight out of the ten cases of KD diagnosed from April 15 to 20 May 2020 also tested positive for SARS-CoV-2 infection [ 19 ].…”

“…A spike of ten Kawasaki-disease-like cases was also observed following the initial wave of COVID-19 infections in a single-center report from Italy, with two of the patients testing positive for SARS-CoV-2 infection [ 20 ]. In all three of these studies, patients diagnosed with KD were on average older, more likely to have cardiac abnormalities such as myocarditis and coronary artery aneurysms, and were also more likely to require intensive care and adjunctive therapy in addition to IVIG treatment [ 18 , 19 , 20 ]. Because these spikes in KD incidence rates appeared to immediately follow a surge in local COVID-19 infection numbers, it seems reasonable to postulate that SARS-CoV-2 may be an infectious trigger leading to the development of KD.…”