Imaging findings in acute pediatric coronavirus disease 2019 (COVID-19) pneumonia and multisystem inflammatory syndrome in children (MIS-C).

The two primary manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children are acute coronavirus disease 2019 (COVID-19) pneumonia and multisystem inflammatory syndrome (MIS-C). While most pediatric cases of acute COVID-19 disease are mild or asymptomatic, some children are at risk for developing severe pneumonia. In MIS-C, children present a few weeks after SARS-CoV-2 exposure with a febrile illness that can rapidly progress to shock and multiorgan dysfunction. In both diseases, the clinical and laboratory findings can be nonspecific and present a diagnostic challenge. Thoracic imaging is commonly obtained to assist with initial workup, assessment of disease progression, and guidance of therapy. This paper reviews the radiologic findings of acute COVID-19 pneumonia and MIS-C, highlights the key distinctions between the entities, and summarizes our understanding of the role of imaging in managing SARS-CoV-2-related illness in children.

A comparison of pulmonary embolism in pediatric and adult patients with acute COVID-19.

BACKGROUND: COVID-19 is associated with pulmonary embolism (PE) in adults. However, the rate of PE in pediatric patients with acute COVID-19 evaluated by CT pulmonary angiography (CTPA) has not been evaluated. OBJECTIVE: Determine PE rate in pediatric patients with acute COVID-19 and compare to adults. MATERIALS AND METHODS: A retrospective review of CTPA studies, performed between March 2020 and January 2021 on pediatric patients with acute COVID-19, but not MIS-C, was performed. CTPAs performed on an adult cohort of acute COVID-19 patients during April 2020 were reviewed for comparison. Pediatric and chest radiologists independently reviewed CTPAs of pediatric and adult patients, respectively. RESULTS: Of the 355 acute COVID-19 pediatric patients treated during the study period, 14 (16.6 ± 4.8y, median-18.5y, 64% female) underwent CTPA. Of the 1868 acute COVID-19 adults treated during two weeks in April 2020, 50 (57.2 ± 17.0y, median-57.0y, 42% female) underwent CTPA. The PE rate was 14% in the pediatric group (2 patients) and 18% in the adult group (9 patients) (p = 1.0). Both pediatric patients with PE were obese, over 18y, and had asthma, diabetes mellitus, or hypertension. No child<18y with acute COVID-19 had PE. In the adult cohort, higher alanine-aminotransferase and D-dimer levels were associated with PE (p = 0.04 and p = 0.004, respectively). CONCLUSION: Despite similar PE rates in pediatric and adult patients, PE occurred in acute COVID-19 pediatric patients who were >18y, obese, and had at least 1 comorbidity. Children <18y with COVID-19 did not have PE.

Review of COVID-19, part 2: Musculoskeletal and neuroimaging manifestations including vascular involvement of the aorta and extremities.

The coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world resulting in severe morbidity, mortality and economic hardship, altering the landscape of healthcare forever. Its devastating and most frequent thoracic and cardiac manifestations have been well reported since the start of the pandemic. Its extra-thoracic manifestations are myriad and understanding them is critical in diagnosis and disease management. The role of radiology is growing in the second wave and second year of the pandemic as the multiorgan manifestations of COVID-19 continue to unfold. Musculoskeletal, neurologic and vascular disease processes account for a significant number of COVID-19 complications and understanding their frequency, clinical sequelae and imaging manifestations is vital in guiding management and improving overall survival. The authors aim to provide a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19. In Part I, abdominal manifestations of COVID-19 in adults and multisystem inflammatory syndrome in children will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Review of COVID-19, part 1: Abdominal manifestations in adults and multisystem inflammatory syndrome in children.

The coronavirus disease 2019 (COVID -19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world, resulting in severe morbidity, mortality and economic hardship, and altering the landscape of healthcare forever. Although primarily a pulmonary illness, it can affect multiple organ systems throughout the body, sometimes with devastating complications and long-term sequelae. As we move into the second year of this pandemic, a better understanding of the pathophysiology of the virus and the varied imaging findings of COVID-19 in the involved organs is crucial to better manage this complex multi-organ disease and to help improve overall survival. This manuscript provides a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19 with the exception of unique cardiothoracic features associated with multisystem inflammatory syndrome in children (MIS-C). In Part I, extra-thoracic manifestations of COVID-19 in the abdomen in adults and features of MIS-C will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Thoracic Imaging Findings of Multisystem Inflammatory Syndrome in Children Associated with COVID-19: What Radiologists Need to Know Now.

The coronavirus disease 2019 (COVID-19) global pandemic is an ongoing public health emergency, with over 4 million confirmed cases worldwide. Due to the novel nature of this coronavirus and our evolving understanding of its pathophysiology, there is continued uncertainty surrounding diagnosis and management of COVID-19, especially in pediatric patients. In addition, a new febrile hyperinflammatory Kawasaki-like syndrome (also known as multisystem inflammatory syndrome in children, or MIS-C) has emerged in pediatric patients with temporal association to COVID-19 infection. This review article aims to provide an up-to-date review of the clinical and imaging findings of pediatric MIS-C associated with COVID-19, compared with typical acute pediatric COVID-19 infection, with an emphasis on thoracic imaging findings. Supplemental material is available for this article. © RSNA, 2020.

Imaging Findings in Multisystem Inflammatory Syndrome in Children (MIS-C) Associated With Coronavirus Disease (COVID-19).

BACKGROUND. A multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease (COVID-19) has recently been described. OBJECTIVE. The purpose of our study was to evaluate the imaging findings of MIS-C associated with COVID-19. METHODS. Imaging studies and medical records of patients (age range, 0-20 years) admitted with MIS-C between April 22 and May 21, 2020, were retrospectively reviewed. Thoracic imaging studies were evaluated for parenchymal, mediastinal and hilar, and cardiovascular abnormalities. Abdominal imaging studies were evaluated for abnormalities of solid viscera, hollow viscera, and the peritoneum as well as the mesentery and retroperitoneum. Studies were reviewed independently by two radiologists, and disagreements were resolved by a third senior radiologist. RESULTS. Sixteen patients (10 male and six female patients; age range, 20 months-20 years) were included in this study. All 16 patients presented with fever. Other presenting signs and symptoms included the following: vomiting (12/16, 75%), abdominal pain (11/16, 69%), rash (10/16, 63%), conjunctivitis (8/16, 50%), diarrhea (7/16, 44%), headache (6/16, 38%), and sore throat (5/16, 31%). Shortness of breath and cough were each present in one patient. Chest radiography showed cardiomegaly (10/16, 63%), congestive heart failure or cardiogenic pulmonary edema (9/16, 56%), atelectasis (9/16, 56%), pleural effusions (7/16, 44%), acute respiratory distress syndrome (2/16, 13%), and pneumonia (1/16, 6%). Eight patients (50%) were evaluated for pulmonary embolism (PE) (six [75%] by CT angiography [CTA] and two [25%] by ventilation-perfusion scintigraphy). In two of the eight patients (25%), CTA showed a segmental PE. Abdominal imaging findings (ultrasound, CT, and radiography) included small-volume ascites (6/16, 38%), hepatomegaly (6/16, 38%), echogenic kidneys (5/16, 31%), bowel wall thickening (3/16, 19%), gallbladder wall thickening (3/16, 19%), mesenteric lymphadenopathy (2/16, 13%), splenomegaly (1/16, 6%), and bladder wall thickening (1/16, 6%). The frequencies of findings based on all the reviewed modalities were as follows: cardiomegaly (12/16, 75%), pleural effusion (10/16, 63%), and atelectasis (10/16, 63%). Absolute interobserver agreement was 0.69-1 for thoracic findings and 0.17-1 for abdominal findings. Fifteen patients (94%) were discharged from the hospital (length of hospital stay: range, 3-20 days), and one patient remained in the hospital at the end of the study period. There were no mortalities. CONCLUSION. MIS-C associated with COVID-19 is characterized predominantly by cardiovascular abnormalities, although solid visceral organ, gallbladder, and bowel abnormalities as well as ascites are also seen, reflecting a multisystemic inflammatory process. CLINICAL IMPACT. The constellation of imaging findings in the setting of COVID-19 may alert radiologists to the diagnosis of MIS-C before rapid deterioration of patients.