Distinct characteristics of multisystem inflammatory syndrome in children in Poland

Abstract

During the winter months of 2020/2021 a wave of multisystem inflammatory syndrome in children (MIS-C) emerged in Poland. We present the results of a nationwide register aiming to capture and characterise MIS-C with a focus on severity determinants. The first MIS-C wave in Poland was notably high, hence our analysis involved 274 children. The group was 62.8% boys, with a median age of 8.8 years. Besides one Asian, all were White. Overall, the disease course was not as severe as in previous reports, however. Pediatric intensive care treatment was required for merely 23 (8.4%) of children, who were older and exhibited a distinguished clinical picture at hospital admission. We have also identified sex-dependent differences; teenage boys more often had cardiac involvement (decreased ejection fraction in 25.9% vs. 14.7%) and fulfilled macrophage activation syndrome definition (31.0% vs. 15.2%). Among all boys, those hospitalized in pediatric intensive care unit were significantly older (median 11.2 vs. 9.1 years). Henceforth, while ethnicity and sex may affect MIS-C phenotype, management protocols might be not universally applicable, and should rather be adjusted to the specific population.

A tendency to worse course of multisystem inflammatory syndrome in children with obesity: MultiOrgan Inflammatory Syndromes COVID-19 related study

“…Moving forward in reference to a US surveillance study, obesity (up to 39% vs. 9.1% in obesity and 6.0% vs. 16.0% in overweightedness) was linked to decreased cardiac function (31), contrary to our findings that did not confirm a difference between the study and control groups in cases of cardiovascular abnormalities, including decreased left ventricular ejection fraction. This might be explained by a tendency toward a milder course of the disease in our population (20,21); however, it demands further investigation.…”

“…We analyzed the MOIS-CoR database containing data collected between 4 March 2020 and 20 February 2021. The database developments were adopted and described previously ( 20 , 21 ). The data were collected using a special online form that was created and standardized by a multicenter group of experts from all over the country.…”

Clinical characteristics of children with MIS-C fulfilling classification criteria for macrophage activation syndrome

“…We analyzed the data from the Polish MIS-C registry of the MultiOrgan Inflammatory Syndromes COVID-19 Related (MOIS-CoR) Study, including the period from March 4, 2020 (when the first COVID-19 case in Poland was confirmed) to April 20, 2021 ( 42 ). Anonymous patient data from 42 pediatric hospitals across the country were extracted from patient records and collected using a web-based form developed for this purpose.…”

“…The inclusion criteria for the MOIS-CoR registry and patient eligibility have been presented previously ( 42 ). We adopted the WHO definition of MIS-C. MAS was diagnosed based on the 2016 Classification Criteria for Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis ( 33 ).…”

“…In addition, laboratory results on admission and at peak (minimum or maximum) were also analyzed. The study's standard definitions and measures, including laboratory and echocardiographic abnormalities, level of consciousness, and nutritional status, have been described in detail in a previous study ( 42 ).…”