Affinché non MIS-Cappi il caso: la sindrome infiammatoria multisistemica SARS-CoV-2-correlata

Background - Covid-19 is less frequent and milder in children than in adults. However, cases of multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (MIS-C) have been reported in children, whose phenotype resembles atypical Kawasaki disease. Objectives - The paper describes the incidence as well as clinical, laboratory and radiological findings of MIS-C. Materials and methods - In the Paediatric Infectious Disease Centre of Palermo (Italy), a targeted surveillance for MIS-C from March 2020 to January 2021 was conducted. Case definition included WHO, UK and US criteria. Results - The paper reports the cases of 9 patients with MIS-C out of which 8 (88%) were hospitalized after September 2020. 44% were male and their median age was 6.5 years. Organ-system involvement included gastrointestinal (66%), cardiovascular (66%), mucocutaneous (88%), reticuloendothelial (77%) and respiratory (55%) systems. C-reactive protein (CRP), procalcitonin, D-dimer and pro-B-type natriuretic peptide levels (pro-BNP) were high in all patients. Chest radiography showed bilateral ground glass-opacities (55%) and pleural effusions (44%). Abdominal imaging findings included small-volume ascites (55%) and mesenteric lymphadenopathy (22%). Echocardiogram showed transient valves regurgitation (55%). In all the patients, the left ventricular ejection fraction was normal and coronary-artery aneurysms were not documented. They were treated with immunomodulating therapies. All patients neither received intensive care nor died. Conclusions - MIS-C represents a new systemic inflammatory syndrome with a phenotype resembling Kawasaki disease. MIS-C remains a rare condition, in which gastrointestinal and mucocutaneous involvement is predominant, nevertheless cardiovascular involvement must be investigated. MIS-C could be suspected even if SARS-CoV-2 exposure precedes the onset of the symptoms by more than 6 weeks. In most cases, a good prognosis might be expected.