Chest radiograph features of multisystem inflammatory syndrome in children (MIS-C) compared to pediatric COVID-19

Abstract

Background: Although the radiographic features of coronavirus disease 2019 (COVID-19) in children have been described, the distinguishing features of multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19 are not well characterized.

Objective: We compared the chest radiographic findings of MIS-C with those of COVID-19 and described other distinguishing imaging features of MIS-C.

Materials and methods: We performed a retrospective case series review of children ages 0 to 18 years who were hospitalized at Children's Healthcare of Atlanta from March to May 2020 and who either met the Centers for Disease Control and Prevention (CDC) case definition for MIS-C (n=11) or who had symptomatic, laboratory-confirmed COVID-19 (n=16). Two radiologists reviewed the most severe chest radiographs for each patient. The type and distribution of pulmonary opacities and presence or absence of pleural effusions were recorded. The chest radiographs were categorized based on potential COVID-19 imaging findings as typical, indeterminate, atypical or negative. An imaging severity score was also assigned using a simplified version of the Radiographic Assessment of Lung Edema Score. Findings were statistically compared between patients with MIS-C and those with COVID-19. Additional imaging findings of MIS-C were also described.

Results: Radiographic features of MIS-C included pleural effusions (82% [9/11]), pulmonary consolidations (73% [8/11]) and ground glass opacities (91% [10/11]). All of the lung opacities (100% [10/10]) were bilateral, and the majority of the pleural effusions (67% [6/9]) were bilateral. Compared to children with COVID-19, children with MIS-C were significantly more likely to develop pleural effusions on chest radiograph (82% [9/11] vs. 0% [0/0], P-value <0.01) and a lower zone predominance of pulmonary opacifications (100% [10/10] vs. 38% [5/13], P-value <0.01). Children with MIS-C who also had abdominal imaging had intra-abdominal inflammatory changes.

Conclusion: Key chest radiographic features of MIS-C versus those of COVID-19 were pleural effusions and lower zone pulmonary opacifications as well as intra-abdominal inflammation. Elucidating the distinguishing radiographic features of MIS-C may help refine the case definition and expedite diagnosis and treatment.

Keywords: Abdomen; Chest; Children; Computed tomography; Coronavirus disease 2019; Multisystem inflammatory syndrome in children; Radiography; Ultrasound.

Fig. 1

Chest radiographs of children with coronavirus disease 2019 (COVID-19). a Posteroanterior chest radiograph in a 15-year-old boy with COVID-19 demonstrates a unilateral ground glass opacity (arrow) in the left lung. Categorization: indeterminate (based on a unilateral opacity). Severity score: 1. b Anteroposterior chest radiograph in a 17-year-old boy with COVID-19 demonstrates bilateral multifocal consolidative and ground glass opacities (arrows). Categorization: indeterminate (based on multifocal opacities without a specific distribution). Severity score: 5

Fig. 2

Chest radiographs of children with multisystem inflammatory syndrome in children (MIS-C). a Anteroposterior (AP) chest radiograph in a 12-year-old boy with MIS-C demonstrates bilateral consolidative and ground glass opacities (arrows) in a peripheral lower zone distribution. Categorization: typical (based on bilateral peripheral opacities). Severity score: 4. b AP chest radiograph in a 10-year-old girl demonstrates bilateral consolidative and ground glass opacities (arrows) in a peripheral lower zone distribution. Categorization: typical. Severity score: 4. c AP chest radiograph in a 4-year-old boy demonstrates a right-side pleural effusion (arrow), a right-side ground glass opacity and a left-side consolidative opacity. The opacities are in a lower zone distribution. Categorization: atypical (based on the presence of a pleural effusion). Severity score: 4. d AP chest radiograph in a 3-year-old boy demonstrates bilateral pleural effusions (arrows) and bilateral ground glass opacities in a peripheral lower zone distribution. Categorization: atypical (based on the presence of a pleural effusion). Severity score: 4

Fig. 3

Additional imaging findings in children with multisystem inflammatory syndrome in children (MIS-C). a Axial CT of the abdomen and pelvis (volume computed tomography dose index [CTDI_vol] 16.23 mGy) in a 12-year-old boy with MIS-C demonstrates an enlarged mesenteric lymph node (x), mesenteric edema (star) and bowel wall thickening of the colon (arrow). b Transverse ultrasound of the abdomen in a 5-year-old girl with MIS-C demonstrates an enlarged mesenteric lymph node measuring 3.4 cm (denoted by calipers). c Transverse ultrasound of the gallbladder in an 8-year-old boy demonstrates gallbladder wall thickening (arrow)