Objective: The aim of this study was to analyse epidemiology and clinical course of paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in the Czech Republic. Methods: We performed a retrospective-prospective nationwide observational study based on patients hospitalised with PIMS-TS according to World Health Organization definition and who were admitted to a hospital in the Czech Republic between November 1st, 2020, and May 31st, 2021.
The anonymised data of patients (demographic and clinical data) were obtained from their medical records. Some of the data from the above-mentioned study period were compared with the results of a smaller set of patients from the next pandemic wave.
The second nationwide observation period followed from June 1st, 2021, to March 31st, 2022. This period was characterized by prevailing delta and subsequently omicron variants.
Results: Between November 1st, 2020 and May 31st, 2021, the total number of diagnosed patients with PIMS-TS in the Czech Republic was 207. The overall incidence was 1:10,100 of the paediatric population aged 0-19 years and 1:1,127 out of all children who tested positive for SARS-CoV-2, respectively.
During follow-up, only two patients (1.2%) had persistent coronary artery dilatation, all patients had normal cardiac function. Between June 1st, 2021 and March 31st, 2022, PIMS-TS was diagnosed in additional 222 children.
Whereas PIMS-TS was frequent during the prevailing delta variant, the predominating omicron variant led to its decline to one fourth in relation to numbers of those tested positively for SARS-CoV-2. The total number of children affected by PIMS-TS reached 429, with no reported fatalities.
Concslusion: Above expectation outcome with no death could be explained by awareness campaigns and national guidelines with early use of combined immunosuppressive treatment.