Kawasaki Disease Associated with SARS-CoV2 in a Pair of Triplets

The etiology of Kawasaki disease (KD) and its precise genetic basics remain unknown. Genetic variants affecting immunity have been found in some patients. The occurrence of KD in siblings is rare, but KD pedigrees with multiple affected members have been described in Japan and North America. Cases in twins have been documented. We report 2 pairs of trizygotic triplets who developed KD associated with SARS-CoV2 infection from 2 different families. Our cases show that KD is multifactorial in origin, and both infectious etiology (particularly SARS-CoV2 as in our cases) and genetic factors are relevant in the disease.

Multisystem Inflammatory Syndrome in Children in Western Countries? Decreasing Incidence as the Pandemic Progresses?: An Observational Multicenter International Cross-sectional Study

BACKGROUND

SARS-CoV-2 variations as well as immune protection after previous infections and/or vaccination may have altered the incidence of multisystemic inflammatory syndrome in children (MIS-C). We aimed to report an international time-series analysis of the incidence of MIS-C to determine if there was a shift in the regions or countries included into the study.

METHODS

This is a multicenter, international, cross-sectional study. We collected the MIS-C incidence from the participant regions and countries for the period July 2020 to November 2021. We assessed the ratio between MIS-C cases and COVID-19 pediatric cases in children <18 years diagnosed 4 weeks earlier (average time for the temporal association observed in this disease) for the study period. We performed a binomial regression analysis for 8 participating sites [Bogotá (Colombia), Chile, Costa Rica, Lazio (Italy), Mexico DF, Panama, The Netherlands and Catalonia (Spain)].

RESULTS

We included 904 cases of MIS-C, among a reference population of 17,906,432 children. We estimated a global significant decrease trend ratio in MIS-C cases/COVID-19 diagnosed cases in the previous month ( P < 0.001). When analyzing separately each of the sites, Chile and The Netherlands maintained a significant decrease trend ( P < 0.001), but this ratio was not statistically significant for the rest of sites.

CONCLUSIONS

To our knowledge, this is the first international study describing a global reduction in the trend of the MIS-C incidence during the pandemic. COVID-19 vaccination and other factors possibly linked to the virus itself and/or community transmission may have played a role in preventing new MIS-C cases.