Keywords: ASO, antistreptolysin O; BNP, brain-natriuretic peptide; CBC, complete blood count; CDC, Center for Disease Control; COVID-19; COVID-19, severe viral respiratory infection caused by SARS-CoV-2; CRP, C-reactive protein; CSS, cytokine storm syndrome; ECMO, extracorporeal membrane oxygenation; Fever; GI, gastrointestinal; HLH, hemophagocytic lymphohistiocytosis; ICU, intensive care unit; IVIG, intravenous immunoglobulin; Inflammation; KD, Kawasaki disease; LDH, lactate dehydrogenase; LFTs, liver function tests; MAS, macrophage activation syndrome; MIS-C; MIS-C, Multisystem Inflammatory Syndrome in Children; PCAID, Pediatric COVID-19 Associated Inflammatory Disorder; PMIS, Pediatric Multisystem Inflammatory Syndrome; PT, prothrombin Time; PTT, partial Thromboplastin Time; Pediatric; SARS-CoV-2; TNF, tumor necrosis factor; VA, veno-arterial; VTE, venous thromboembolic events.