Background: Cardiac injury and myocarditis have been described in adults with COVID-19. SARS-CoV-2 infection in children is typically minimally symptomatic. We report a series of febrile pediatric patients with acute heart failure potentially associated with SARS-CoV-2 infection and the multisystem inflammatory syndrome in children (MIS-C) as defined by the US Centers for Disease Control. Methods: Over a two-month period contemporary with the SARS-CoV-2 pandemic in France and Switzerland, we retrospectively collected clinical, biological, therapeutic, and early outcomes data in children who were admitted to pediatric intensive care units in 14 centers for cardiogenic shock, left ventricular dysfunction and severe inflammatory state. Results: Thirty-five children were identified and included in the study. Median age at admission was 10 years (range 2-16 years). Co-morbidities were present in 28% including asthma and overweight. Gastrointestinal symptoms were prominent. Left ventricular ejection fraction was <30% in one third; 80% required inotropic support with 28% treated with ECMO. Inflammation markers were suggestive of cytokine storm (interleukin 6 median 135 pg/mL) and macrophage activation (D-dimer median 5284 ng/mL). Mean brain natriuretic peptide was elevated (5743 pg/mL). Thirty-one/35 (88%) patients tested positive for SARS-CoV-2 infection by PCR of nasopharyngeal swab or serology. All patients received intravenous immune globulin, with adjunctive steroid therapy used in one third. Left ventricular function was restored in the 25/35 of those discharged from the intensive care unit. No patient died, and all patients treated with ECMO were successfully weaned. Conclusion: Children may experience an acute cardiac decompensation due to severe inflammatory state following SARS-CoV-2 infection (multisystem inflammatory syndrome in children - MIS-C). Treatment with immune globulin appears to be associated with recovery of left ventricular systolic function.

Key PointsQuestionIs there an association between treatment with intravenous immunoglobulins (IVIG) plus methylprednisolone vs IVIG alone and course of fever in multisystem inflammatory syndrome in children (MIS-C) associated with severe acute respiratory syndrome coronavirus 2?FindingsThis retrospective cohort study included 111 children with MIS-C. After propensity score matching, the rate of treatment failure (defined by the persistence of fever 2 days after the introduction of first-line therapy or recrudescence of fever within 7 days) for those who received IVIG plus methylprednisolone vs IVIGs alone was 9% vs 51%, a difference that was statistically significant.MeaningCombined treatment with methylprednisolone vs IVIG alone was associated with a better course of fever in MIS-C.

No abstract

No abstract

Myocarditis and Kawasaki disease are common but usually distinct diseases in children. During the coronavirus pandemic (COVID-19), reports of a new form of myocarditis with clinical features of Kawasaki appeared. We investigated the place of this new disease in the spectrum encompassing Kawasaki disease and myocarditis. Thirty two consecutive children referred to our centre for a suspicion of Kawasaki or a diagnosis of myocarditis were included and eventually divided into four groups: 11 Kawasaki diseases, 6 Kawasaki syndromes (children with another diagnosis), 7 myocarditis without Kawasaki clinical feature and 7 myocarditis with incomplete Kawasaki clinical features. All were treated with immunoglobulins except those of the myocarditis group. The survival rate was 91%. The 7 children with myocarditis and clinical features of incomplete Kawasaki were all positive for SARS-CoV-2. They had a transient myocardial failure with a favourable course and none had coronary artery disease. Conclusion : Every COVID-19 child within our population had a mild to severe myocarditis and presented with fever plus two or three Kawasaki clinical features. Short-term evolution was good for these children. This new disease seems to fill the gap between isolated myocarditis and Kawasaki disease. What is Known: • A new paediatric disease close to Kawasaki disease appeared during the COVID-19 pandemic What is New: • In our population , children presented with fever , vivid Kawasaki clinical features ( although the Kawasaki syndrome was always incomplete ) and a myocarditis without coronary abnormalities. • The new disease fills the gap between paediatric myocarditis and Kawasaki disease but its prognosis is much better.