The clinical presentation was backed by abnormal laboratory or imaging findings, comparable with a pro-inflammatory state of the host. cardiac involvement. Thirty of the 37 children (81%) required admission to the intensive care unit, with good recovery in all cases. Chest radiographs exhibited cardiomegaly in 54% and indicators of pulmonary venous hypertension/congestion in 73%. The most common chest CT abnormalities were ground-glass and interstitial opacities (83%), airspace consolidation (58%), pleural effusion (58%) and bronchial wall thickening (42%). Echocardiography revealed impaired cardiac function in half of cases (51%) and coronary artery abnormalities in 14%. Cardiac MRI showed myocardial oedema in 58%, pericardial effusion in 42% and decreased left ventricular function in 25%. Twenty children required imaging for abdominal symptoms, the commonest abnormalities being free fluid (71%) and terminal ileum wall thickening (57%). Twelve children underwent brain imaging, showing abnormalities in two cases. Conclusion Children with multisystem inflammatory syndrome showed pulmonary, cardiac, abdominal and brain imaging findings, reflecting the multisystem inflammatory disease. Awareness of the imaging features of this disease is usually important for early diagnosis and treatment. Supplementary Information The online version contains supplementary material available at 10.1007/s00247-021-05065-0. coronavirus disease 2019, C-reactive protein, multisystem inflammatory syndrome in children associated with COVID-19, polymerase chain reaction, severe acute respiratory syndrome coronavirus 2 Different groups of radiologists and subspecialised paediatricians reviewed the submitted medical data and imaging studies relating to their area of expertise. Clinical and laboratory data were reviewed by two paediatric rheumatologists and a paediatric cardiologist with 21, 25 and 12?years of experience, respectively (M.C., O.N. and I.V.). Chest radiographs, CT, echocardiography and cardiac MRI were analysed by a group of five senior paediatric radiologists and a paediatric cardiologist with 2, 8, 8, 11, 20 and 12?years of experience in paediatric chest imaging, respectively (M.N., J.V.S., A.S., M.G.M, C.J.K. and I.V.). Abdominal US, CT and MRI were evaluated by two H3/h paediatric radiologists, each with 10?years of experience in paediatric abdominal imaging Velneperit (S.C.S. and S.T.). Cranial CT and MRI were analysed by a paediatric neuroradiologist and paediatric radiologist with 6 and 7?years of experience, respectively (F.D. and P.C.-D.). Not all imaging was available for review; in cases submitted without images, we used radiologic and echocardiography findings reported in the questionnaire. The different groups of radiologists reviewed the images independently before comparing their results and reaching a consensus decision around the abnormalities, without disagreements. Descriptive analyses of the patient demographics, clinical and laboratory data, and imaging findings were performed and tabulated. Results Clinical and laboratory findings In this case series, we included 37 children who met the criteria for multisystem inflammatory syndrome associated with COVID-19 (21 males, 16 girls; median age 8.0?years, interquartile range [IQR] 3.3C10.3?years). Patient characteristics and clinical findings are summarized in Table ?Table2.2. We received cases from Spain ((%)Males, 21 (57%) Girls, 16 (43/%) Family contact, (%)14 (38%)Symptoms, (%)?Fever37 (100%)?Abdominal pain25 (68%)?Rash20 (54%)?Conjunctivitis14 (38%)?Cough12 (32%)?Dyspnoea9 (24%)?Vomiting5 (14%)?Diarrhoea4 (11%)?Headaches4 (11%)?Lymphadenopathy4 (11%)?Chest pain3 (8%) Open in a separate window years Table 3 Pathological laboratory results of 37 children with multisystem inflammatory syndrome associated with coronavirus disease 2019 (COVID-19) C-reactive protein, immunoglobulin G, interleukin 6, interquartile range (min Q1Cmax Q3), not available, N-terminal pro b-type natriuretic peptide, polymerase chain reaction The most common clinical presentation was fever and gastrointestinal and respiratory symptoms, summarized in Table ?Table2.2. Contact with SARS-CoV-2-positive family members was reported in 14 cases (38%): 5 had positive Velneperit immunoglobulin G (with unfavorable PCR), 2 had positive PCR (serology not performed), 1 was positive for both assessments, 2 were unfavorable for both assessments, 3 were unfavorable for PCR (serology not obtained) and 1 was positive PCR obtained 3?weeks before the Velneperit disease onset. Thirty of 37 (81%) children required admission to the intensive care unit because of clinical.