Extracardiac Imaging Findings in COVID-19 Associated Multisystem Inflammatory Syndrome in Children

Background: – COVID-19 associated Multisystem Inflammatory Syndrome in Children (MIS-C) is an emerging disease that presents with inflammation of multiple organs. The extracardiac radiographic manifestations of this syndrome are not well understood.Objective – We reviewed the radiologic findings of MIS-C in a cohort of children with a confirmed diagnosis of the syndrome.Materials and methods – In a retrospective study from 4/1/2020 to 5/22/2020, we reviewed imaging studies of 38 children with MIS-C, 21 females (55%) and 17 males (45%), with an average age of 9.2 years (range 1.3 – 20 years). Thirty six had chest radiographs, 6 had abdominal radiographs, 12 had abdominal sonograms or MRI, 2 had neck sonograms, and 3 had brain MRI.Results – 28 patients had pulmonary disease, with 24 (86%) having bilateral opacities, mostly diffuse (n=16, 57%). The most common abnormalities were peribronchial thickening (n=19, 68%), ground glass opacities (n=15, 54%) and consolidation (n=5, 18%). Pleural effusions were only present in children 10 years of age and under, and ground glass opacities were seen more often in older patients (59% vs. 26%, P<0.05). On abdominal imaging, small volume ascites was the most common finding (n=6, 50%). Other findings included right lower quadrant bowel wall thickening (n=3, 25%), gallbladder wall thickening (n=3, 25%), and cervical (n=2) or abdominal (n=2) lymphadenophathy. Of 3 patients with brain MRI, one had bilateral parietooccipital abnormalities and another papilledema.Conclusion – COVID-19 associated MIS-C causes a constellation of findings in the chest and abdomen, most often showing bilateral diffuse pulmonary abnormalities and small volume ascites.