Description and outcomes of Afro-Caribbean children treated for multisystem inflammatory syndrome in the French West Indies.

Introduction: Several studies have reported a higher frequency and greater morbidity and mortality of multisystem inflammatory syndrome in children (MIS-C) of black African descent. Objectives: We aimed to describe the clinical, laboratory and echocardiographic characteristics as well as outcomes of children with MIS-C requiring admission to a pediatric intensive care unit (PICU) in the French West Indies (FWI), where the majority of the population is Afro-Caribbean. Methods: Ambidirectional observational cohort study between April 1, 2020 and August 31, 2022. Children (age ≤18 years) with MIS-C and organ failure were included. Every patient was monitored and treated following the same protocol, with repeated biological tests, echocardiography, intravenous steroids and polyvalent immunoglobulins. The primary outcomes were clinical, laboratory and echocardiography characteristics. Results: Forty children (median age 7 years, range: 5-11) were included. The majority (77 %) were included prospectively. Thirty-five (87 %) had gastrointestinal symptoms, 30 (75 %) presented initial heart failure (with persisting diastolic dysfunction at day 7) and 18 (45 %) had pericarditis. Sixteen (40 %) were in cardiogenic shock and required inotropic support. Median duration of inotropic support and hospitalization in PICU were respectively 4 and 5 days. The evolution curves of the inflammatory variables matched after treatment. The clinical outcomes were favorable. The Delta variant was associated with the highest incidence of MIS-C. Conclusion: This is the first description of MIS-C course among children of Afro-Caribbean descent. The outcomes were good, without any death or cardiac sequelae. Our work does not support an ethnic susceptibility for severity of MIS-C in Afro-Caribbean population.