Characteristics and Outcomes of US Children and Adolescents With Multisystem Inflammatory Syndrome in Children (MIS-C) Compared With Severe Acute COVID-19

Acute Hypoxemic Respiratory Failure in Children at the Start of COVID-19 Outbreak: A Nationwide Experience

Study design: This is a prospective, multicenter, and observational study with the aim of describing physiological characteristics, respiratory management, and outcomes of children with acute hypoxemic respiratory failure (AHRF) from different etiologies receiving invasive mechanical ventilation (IMV) compared with those affected by SARS-CoV-2. Methods and Main Results: Twenty-eight patients met the inclusion criteria: 9 patients with coronavirus disease 2019 (COVID-19) and 19 patients without COVID-19. Non-COVID-19 patients had more pre-existing comorbidities (78.9% vs. 44.4%) than COVID-19 patients. At AHRF onset, non-COVID-19 patients had worse oxygenation (PaO₂/FiO₂ = 95 mmHg (65.5–133) vs. 150 mmHg (105–220), p = 0.04), oxygenation index = 15.9 (11–28.4) vs. 9.3 (6.7–10.6), p = 0.01), and higher PaCO₂ (48 mmHg (46.5–63) vs. 41 mmHg (40–45), p = 0.07, that remained higher at 48 h: 54 mmHg (43–58.7) vs. 41 (38.5–45.5), p = 0.03). In 12 patients (5 COVID-19 and 7 non-COVID-19), AHRF evolved to pediatric acute respiratory distress syndrome (PARDS). All non-COVID-19 patients had severe PARDS, while 3 out of 5 patients in the COVID-19 group had mild or moderate PARDS. Overall Pediatric Intensive Care Medicine (PICU) mortality was 14.3%. Conclusions: Children with AHRF due to SARS-CoV2 infection had fewer comorbidities and better oxygenation than patients with non-COVID-19 AHRF. In this study, progression to severe PARDS was rarely observed in children with COVID-19.

Comparison of coronary artery measurements between echocardiograms and cardiac CT in Kawasaki disease patients with aneurysms

BACKGROUND

American Heart Association (AHA) guidelines for management of Kawasaki disease (KD) rely on coronary artery (CA) z-scores from echocardiograms. Compared with echocardiography, cardiac CT (CCT) offers better visualization of distal segments and evaluation for thrombosis and stenosis. Despite increasing use of CCT in KD, CA z-scores for CCT are not available and measurement concordance between imaging modalities is a critical knowledge gap.

METHODS

We retrospectively reviewed KD patients with CA aneurysms who had concurrent echocardiography and CCT between 2016 and 2020. Patients were included if they had history of CA z-scores of ≥3 on echocardiography during their clinical course. Agreement between CCT and echocardiography was assessed using Bland-Altman analysis.

RESULTS

Paired CCT and echocardiography studies were available in 18 patients (21 studies). The largest CA aneurysms were large/giant (z-score ≥10) in 14 studies, medium (z-score ≥5, <10) in 3 studies, and small (z score ≥2.5, <5) in 2 studies. Intra- and inter-observer reliability for CCT measurements were high for all CA segments (ICC 99.7% and 98.6%). For the LMCA, proximal LAD and proximal and distal RCA there was high correlation between echocardiogram and CCT absolute measurements with wider variation between modalities for the distal LAD and circumflex. Overall, CCT measurements tended to be smaller than echocardiogram measurements, and led to a lower AHA z-score risk classification in 24% of studies.

CONCLUSION

CCT and echocardiography have high agreement for absolute measurements of proximal CA segments, but more measurement discrepancy exists for distal CA segments with bias toward lower dimensions on CCT.

Multisystem inflammatory syndrome in children (MIS-C) occurring in temporal proximity between siblings

We report a pair of siblings who developed multisystem inflammatory syndrome in children (MIS-C) in close temporal proximity after recent exposure to SARS-CoV-2. Both siblings presented with Kawasaki disease-like features and haemodynamic instability, with the onset of symptoms within 6 days of each other. Remarkably, one of the siblings was the elder of a pair of monozygotic twins. The younger monozygotic twin, however, did not develop MIS-C.

Experimental Technologies in the Diagnosis and Treatment of COVID-19 in Patients with Comorbidities

The COVID-19 pandemic has impacted the whole world and raised concerns about its effects on different human organ systems. Early detection of COVID-19 may significantly increase the rate of survival; thus, it is critical that the disease is detected early. Emerging technologies have been used to prevent, diagnose, and manage COVID-19 among the populace in the USA and globally. Numerous studies have revealed the growing implementation of novel engineered systems during the intervention at various points of the disease’s pathogenesis, especially as it relates to comorbidities and complications related to cardiovascular and respiratory organ systems. In this review, we provide a succinct, but extensive, review of the pathogenesis of COVID-19, particularly as it relates to angiotensin-converting enzyme 2 (ACE2) as a viral entry point. This is followed by a comprehensive analysis of cardiovascular and respiratory comorbidities of COVID-19 and novel technologies that are used to diagnose and manage hospitalized patients. Continuous cardiorespiratory monitoring systems, novel machine learning algorithms for rapidly triaging patients, various imaging modalities, wearable immunosensors, hotspot tracking systems, and other emerging technologies are reviewed. COVID-19 effects on the immune system, associated inflammatory biomarkers, and innovative therapies are also assessed. Finally, with emphasis on the impact of wearable and non-wearable systems, this review highlights future technologies that could help diagnose, monitor, and mitigate disease progression. Technologies that account for an individual’s health conditions, comorbidities, and even socioeconomic factors can drastically reduce the high mortality seen among many COVID-19 patients, primarily via disease prevention, early detection, and pertinent management.

Opportunity, Challenge, or Both? Managing Adolescent Socioemotional and Mental Health During Web-Based Learning

The transition to web-based learning during the COVID-19 pandemic has highlighted the need to consider the benefits of and the risks associated with web-based technology for education, media use, and access to resources. Prior to the pandemic, children and adolescents had in-person access to peers; social relationships; educators; health care providers; and, in some cases, mental health resources and medical care in schools and community settings. Due to the introduction of universal masking and physical distancing guidelines to prevent the spread of COVID-19 in early 2020, methods for accessing these resources have shifted dramatically, as people now rely on web-based platforms to access such resources. This viewpoint will explore equity in access to technology for web-based learning, mental health (with a focus on students of color), and the challenge of cultivating meaningful relationships on web-based platforms. Challenges and possible solutions will be offered.

An 11-Year-Old Saudi Arabian Girl Who Presented with Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with SARS-CoV-2 Infection with Coronary Artery Aneurysm and Cardiac Involvement: A Case Report

BACKGROUND Early in the COVID-19 pandemic, children who were infected with severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) with vascular inflammation were described as having a vasculitis similar to Kawasaki's disease. There are now consensus clinical guidelines that have described the presentation and diagnosis of multisystem inflammatory syndrome in children (MIS-C) associated with SARS-CoV-2 infection. This report aims to describe a case of MIS-C in an 11-year-old Saudi Arabian girl who presented with coronary artery aneurysm and cardiac involvement. CASE REPORT We describe an 11-year-old Saudi girl who was asymptomatic for 3 weeks after contracting SARS-CoV-2. Three weeks after suffering a mild flulike illness, she developed a high fever, cough, and severe clinical deterioration within 12 h of admission, including shock, rash, pleural effusion, high inflammatory markers, and a coronary aneurysm. As per current practice, the diagnosis was confirmed as multisystem inflammatory syndrome based on a SARS-CoV-2 test with reverse transcription polymerase chain reaction (RT-PCR) from 2 nasopharyngeal aspirates. Her condition was successfully treated with antibiotics, inotropes, IVIG, aspirin, and Tocilizumab, in addition to high-flow oxygen therapy. Eventually, she was able to return home after fully recovering. CONCLUSIONS The findings in this report suggest that children with MIS-C due to SARS-CoV-2 infection can have a good prognosis, even when they suffer from coronary artery and cardiac involvement. The increasing number of emerging SARS-CoV-2 variants that affect children supports the importance of RT-PCR for the COVID-19 diagnostic test for children with multisystem or cardiovascular inflammation, which may guide the most appropriate clinical management of the variants of MIS-C.

The Heart of the Problem in Multisystem Inflammatory Syndrome in Children

Multisystem inflammatory syndrome in children (MIS-C) is a severe, life-threatening, post-COVID-19 hyperinflammatory illness that is not yet fully understood. In this issue of Med, de Cevins et al. used a multi-parametric approach to define COVID-19-related disease, specifically identifying a molecular signature of the most severe form of COVID-19-related illness: MIS-C with myocarditis.¹

Multisystem inflammatory syndrome in children (MIS-C): a mini-review

Multisystem inflammatory syndrome in children (MIS-C) is a novel, life-threatening hyperinflammatory condition that develops in children a few weeks after infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This disease has created a diagnostic challenge due to overlap with Kawasaki disease (KD) and KD shock syndrome. The majority of patients with MIS-C present with the involvement of at least four organ systems, and all have evidence of a marked inflammatory state. Most patients show an increase in the level of at least four inflammatory markers (C-reactive protein, neutrophil count, ferritin, procalcitonin, fibrinogen, interleukin-6, and triglycerides). Therapy is primarily with immunomodulators, suggesting that the disease is driven by post-infectious immune dysregulation. Most patients, even those with severe cardiovascular involvement, recover without sequelae. Since coronary aneurysms have been reported, echocardiographic follow-up is needed.

Further study is needed to create uniform diagnostic criteria, therapy, and follow-up protocols.

Gastrointestinal Perspective of Coronavirus Disease 2019 in Children-An Updated Review

Gastrointestinal symptoms are common findings in children with severe acute respiratory syndrome coronavirus 2 infection, including vomiting, diarrhoea, abdominal pain, and difficulty in feeding, although these symptoms tend to be mild. The hepato-biliary system and the pancreas may also be involved, usually with a mild elevation of transaminases and, rarely, pancreatitis. In contrast, a late hyper-inflammatory phenomenon, termed multisystem inflammatory syndrome (MIS-C), is characterized by more frequent gastrointestinal manifestations with greater severity, sometimes presenting as peritonitis. Gastrointestinal and hepato-biliary manifestations are probably related to a loss in enterocyte absorption capability and microscopic mucosal damage caused by a viral infection of intestinal epithelial cells, hepatocytes and other cells through the angiotensin conversion enzyme 2 receptor resulting in immune cells activation with subsequent release of inflammatory cytokines. Specific conditions such as inflammatory bowel disease (IBD) and liver transplantation may pose a risk for the more severe presentation of coronavirus disease 2019 (COVID-19) but as adult data accumulate, paediatric data is still limited. The aim of this review is to summarize the current evidence about the effect of COVID-19 on the gastrointestinal system in children, with emphasis on the emerging MIS-C and specific considerations such as patients with IBD and liver transplant recipients.

The global burden of vaccine-preventable infectious diseases in children less than 5 years of age: Implications for COVID-19 vaccination. How can we do better?

Background: Infectious diseases are a leading cause of morbidity and mortality worldwide. As of 2018, the total world population of children < 5 years of age was roughly estimated at 679 million. Of these children, an estimated 5.3 million died of all causes in 2018, with an estimated 700,000 who died of vaccine-preventable infectious diseases; 99% of the children who died had lived in low- and middle-income countries. The infectious diseases that remain major causes of mortality for which vaccines have been shown to provide proven preventive success include, in order of prevalence, are those caused by Streptococcus pneumoniae, Rotavirus, Bordetella pertussis, measles virus, Haemophilus influenzae type b and influenza virus. Objective: The purpose of the present report was to address the global burden of these six vaccine-preventable infectious diseases in children < 5 years of age, together with implications for the prevention of coronavirus disease 2019 (COVID-19) infection in children. Methods: The current immunization strategies for the prevention of the six vaccine-preventable infectious diseases in children are reviewed as a framework for new strategies of vaccine prevention of COVID-19 in children. Results: The burden of addressing vaccine prevention of future infectious disease in children can be effectively pursued through knowledge gained from past experiences with vaccine usage in these six vaccine-preventable childhood infectious diseases. Conclusion: Issues with regard to the burden of disease mortality, disease transmission, and available vaccines as well as vaccine successes and shortcomings for specific pathogens can serve as important landmarks for effective use of future vaccines. Although much success has been made globally in preventing these childhood deaths, much remains to be done.

Clinical features of multisystem inflammatory syndrome in children

PURPOSE OF REVIEW

To review diagnosis, clinical characteristics and treatment of multisystem inflammatory syndrome in children (MIS-C) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

RECENT FINDINGS

MIS-C emerged in spring 2020 as a hyperinflammatory syndrome following SARS-CoV-2 exposure in children. Despite growing awareness of MIS-C, diagnosis remains challenging due to the range of phenotypes and severity. Fever accompanied by shock, cardiac dysfunction, gastrointestinal symptoms, or mucocutaneous signs suggestive of Kawasaki disease, especially in the presence of known or suspected coronavirus disease 2019 exposure, should trigger consideration of MIS-C. However, clinical presentations are highly varied and may overlap with other infectious diseases. Clinicians must maintain a high index of suspicion for MIS-C and be aware that patients may develop coronary artery aneurysms and myocarditis even with few or no Kawasaki disease symptoms. More precise diagnostic criteria and specific biomarkers are needed to aid diagnosis. Intravenous immunoglobulin (IVIG) is first-line therapy, and steroids should be considered as initial adjunctive treatment for patients with severe manifestations or other risk factors. Prompt treatment is essential, as patients may worsen acutely, though overall prognosis is reassuring.

SUMMARY

MIS-C associated with SARS-CoV-2 has varied clinical manifestations. Clinicians must be aware of the common presentation and potential for decompensation and cardiac sequalae to guide appropriate evaluation and treatment.

The impact of the COVID-19 pandemic on the field of pediatric rheumatology

PURPOSE OF REVIEW

The purpose of this review is to discuss the clinical management of children with pediatric rheumatic disease (PRD) during the Coronavirus disease of 2019 (COVID-19) pandemic, as well as the unique role of the pediatric rheumatologist during a time of emerging post-COVID inflammatory sequelae including, multisystem inflammatory syndrome in children (MIS-C).

RECENT FINDINGS

To date, there has been little evidence to suggest that children with PRD, including those on immunomodulatory therapies, are at increased risk for severe COVID-19. Clinical guidance statements have been created to support clinical providers in providing care to children with PRD during the COVID-19 pandemic. Pediatric rheumatologists have also been called upon to assist in the identification and management of post-COVID sequelae, including the rapidly emerging inflammatory illness, MIS-C.

SUMMARY

The COVID-19 era has been defined by a rapid expansion in scientific knowledge and a time of extraordinary local and worldwide collaboration, both within the pediatric rheumatology community, as well as across multiple disciplines. Through collective efforts, we have learned that children with PRD, including those on immunomodulatory therapies, are not at increased risk for severe COVID-19. Pediatric rheumatologists have also worked alongside other disciplines to develop guidance for the management of MIS-C, with the majority of patients experiencing excellent clinical outcomes.

Performance of Cytokine Storm Syndrome Scoring Systems in Pediatric COVID-19 and Multisystem Inflammatory Syndrome in Children

Objective

The objective of this study is to evaluate pediatric patients using existing macrophage activation syndrome (MAS) and hemophagocytic lymphohistiocytosis (HLH) scoring systems to determine how these systems identify patients with cytokine storm syndrome (CSS) in the setting of a multisystem inflammatory syndrome in children (MIS‐C) and active coronavirus disease 2019 (COVID‐19) infection.

Methods

Hospitalized pediatric patients with MIS‐C and active COVID‐19 infection at a single institution were identified. Infectious data, clinical findings, and laboratory values were collected, and patients were stratified by disease severity. Eight historically used scoring systems for MAS, HLH, and CSS were examined in the cohort of patients with MIS‐C and pediatric COVID‐19.

Results

The HLH‐2004 criteria and HScore did not identify any patients as having CSS on admission, with only one patient with COVID‐19 meeting criteria at peak disease severity. The 2016 systemic juvenile idiopathic arthritis (sJIA)/MAS criteria, ferritin/erythrocyte sedimentation rate (ESR) ratio, and COVID‐19 CSS Quick Score most frequently identified CSS in this population and distinguished between COVID‐19 and MIS‐C hyperinflammation. The 2019 MAS/sJIA (MS) score and the COVID‐19–associated hyperinflammatory syndrome (cHIS) criteria were less likely to identify CSS, as the MS score overestimated CSS and the cHIS resulted in similar scores regardless of severity or disease type. The Caricchio COVID‐Cytokine Storm (COVID‐CS) criteria identified patients with COVID‐19 frequently but was less useful in MIS‐C because of its COVID‐19‐specific criteria.

Conclusion

MIS‐C and pediatric COVID‐19 result in relatively unique CSSs and patterns of inflammation. Existing scoring systems for CSSs likely do not capture the full breadth of this disease process in MIS‐C and pediatric COVID‐19.

Demographic and Clinical Factors Associated With Death Among Persons <21 Years Old With Multisystem Inflammatory Syndrome in Children-United States, February 2020-March 2021

Multisystem inflammatory syndrome in children (MIS-C) occurs among persons aged <21 years following severe acute respiratory syndrome coronavirus 2 infection. Among 2818 MIS-C cases, 35 (1.2%) deaths were reported, primarily affecting racial/ethnic minority persons. Being 16–20 years old or having comorbidities was associated with death. Targeting coronavirus disease 2019 prevention among these groups and their caregivers might prevent MIS-C-related deaths.

Inpatient Occupational Therapy Management for a Pediatric Patient With COVID-19 and Multisystem Inflammatory Syndrome in Children: A Case Report

This case report describes the distinct value of occupational therapy services in the treatment of a pediatric patient with coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome in children in an acute care setting. Practice-based evidence was used to design the treatment plan for this patient throughout the course of his hospital stay. Interventions addressed range of motion, strength, functional endurance, activities of daily living (ADLs), instrumental activities of daily living (IADLs), and functional cognition. Occupational therapy goals focused on the progression toward return to baseline functioning and participation in ADLs and IADLs.

Nails and COVID-19 - A comprehensive review of clinical findings and treatment

The SARS‐CoV‐2 infection, responsible for COVID‐19, has raised the interest for infection‐associated muco‐cutaneous symptoms. While dermatologic symptoms in general gained an increasing awareness, affection of the nail organ has been mentioned only recently. We provide a narrative review on COVID‐19 manifestation on the nail organ and add symptoms induced by personal protective measures and SARS‐CoV‐2 vaccination. Available treatment options are discussed.

Characterization and Outcomes of Hospitalized Children With Coronavirus Disease 2019: A Report From a Multicenter, Viral Infection and Respiratory Illness Universal Study (Coronavirus Disease 2019) Registry

OBJECTIVES

Multicenter data on the characteristics and outcomes of children hospitalized with coronavirus disease 2019 are limited. Our objective was to describe the characteristics, ICU admissions, and outcomes among children hospitalized with coronavirus disease 2019 using Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study: Coronavirus Disease 2019 registry.

DESIGN

Retrospective study.

SETTING

Society of Critical Care Medicine Viral Infection and Respiratory Illness Universal Study (Coronavirus Disease 2019) registry.

PATIENTS

Children (< 18 yr) hospitalized with coronavirus disease 2019 at participating hospitals from February 2020 to January 2021.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was ICU admission. Secondary outcomes included hospital and ICU duration of stay and ICU, hospital, and 28-day mortality. A total of 874 children with coronavirus disease 2019 were reported to Viral Infection and Respiratory Illness Universal Study registry from 51 participating centers, majority in the United States. Median age was 8 years (interquartile range, 1.25-14 yr) with a male:female ratio of 1:2. A majority were non-Hispanic (492/874; 62.9%). Median body mass index (n = 817) was 19.4 kg/m2 (16-25.8 kg/m2), with 110 (13.4%) overweight and 300 (36.6%) obese. A majority (67%) presented with fever, and 43.2% had comorbidities. A total of 238 of 838 (28.2%) met the Centers for Disease Control and Prevention criteria for multisystem inflammatory syndrome in children, and 404 of 874 (46.2%) were admitted to the ICU. In multivariate logistic regression, age, fever, multisystem inflammatory syndrome in children, and pre-existing seizure disorder were independently associated with a greater odds of ICU admission. Hospital mortality was 16 of 874 (1.8%). Median (interquartile range) duration of ICU (n = 379) and hospital (n = 857) stay were 3.9 days (2-7.7 d) and 4 days (1.9-7.5 d), respectively. For patients with 28-day data, survival was 679 of 787, 86.3% with 13.4% lost to follow-up, and 0.3% deceased.

CONCLUSIONS

In this observational, multicenter registry of children with coronavirus disease 2019, ICU admission was common. Older age, fever, multisystem inflammatory syndrome in children, and seizure disorder were independently associated with ICU admission, and mortality was lower among children than mortality reported in adults.

Distinct Cytokine and Chemokine Dysregulation in Hospitalized Children With Acute Coronavirus Disease 2019 and Multisystem Inflammatory Syndrome With Similar Levels of Nasopharyngeal Severe Acute Respiratory Syndrome Coronavirus 2 Shedding

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a severe clinical phenotype of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection that remains poorly understood.

METHODS

Hospitalized children <18 years of age with suspected coronavirus disease 2019 (COVID-19) (N = 53) were recruited into a prospective cohort study; 32 had confirmed COVID-19, with 16 meeting the US Centers for Disease Control criteria for MIS-C. Differences in nasopharyngeal viral ribonucleic acid (RNA) levels, SARS-CoV-2 seropositivity, and cytokine/chemokine profiles were examined, including after adjustments for age and sex.

RESULTS

The median ages for those with and without MIS-C were 8.7 years (interquartile range [IQR], 5.5-13.9) and 2.2 years (IQR, 1.1-10.5), respectively (P = .18), and nasopharyngeal levels of SARS-CoV-2 RNA did not differ significantly between the 2 groups (median 63 848.25 copies/mL versus 307.1 copies/mL, P = .66); 75% of those with MIS-C were antibody positive compared with 44% without (P = .026). Levels of 14 of 37 cytokines/chemokines (interleukin [IL]-1RA, IL-2RA, IL-6, IL-8, tumor necrosis factor-α, IL-10, IL-15, IL-18, monocyte chemoattractant protein [MCP]-1, IP-10, macrophage-inflammatory protein [MIP]-1α, MCP-2, MIP-1β, eotaxin) were significantly higher in children with MIS-C compared to those without, irrespective of age or sex (false discovery rate <0.05; P < .05).

CONCLUSIONS

The distinct pattern of heightened cytokine/chemokine dysregulation observed with MIS-C, compared with acute COVID-19, occurs across the pediatric age spectrum and with similar levels of nasopharyngeal SARS-CoV-2 RNA.

Myocarditis With COVID-19 mRNA Vaccines

Myocarditis has been recognized as a rare complication of coronavirus disease 2019 (COVID-19) mRNA vaccinations, especially in young adult and adolescent males. According to the US Centers for Disease Control and Prevention, myocarditis/pericarditis rates are ≈12.6 cases per million doses of second-dose mRNA vaccine among individuals 12 to 39 years of age. In reported cases, patients with myocarditis invariably presented with chest pain, usually 2 to 3 days after a second dose of mRNA vaccination, and had elevated cardiac troponin levels. ECG was abnormal with ST elevations in most, and cardiac MRI was suggestive of myocarditis in all tested patients. There was no evidence of acute COVID-19 or other viral infections. In 1 case, a cardiomyopathy gene panel was negative, but autoantibody levels against certain self-antigens and frequency of natural killer cells were increased. Although the mechanisms for development of myocarditis are not clear, molecular mimicry between the spike protein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and self-antigens, trigger of preexisting dysregulated immune pathways in certain individuals, immune response to mRNA, and activation of immunologic pathways, and dysregulated cytokine expression have been proposed. The reasons for male predominance in myocarditis cases are unknown, but possible explanations relate to sex hormone differences in immune response and myocarditis, and also underdiagnosis of cardiac disease in women. Almost all patients had resolution of symptoms and signs and improvement in diagnostic markers and imaging with or without treatment. Despite rare cases of myocarditis, the benefit-risk assessment for COVID-19 vaccination shows a favorable balance for all age and sex groups; therefore, COVID-19 vaccination is recommended for everyone ≥12 years of age.

Acute Kidney Injury in Pediatric Acute SARS-CoV-2 Infection and Multisystem Inflammatory Syndrome in Children (MIS-C): Is There a Difference?

Objective: To evaluate the prevalence and factors associated with the risk of acute kidney injury (AKI) in pediatric patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and multisystem inflammatory syndrome in children (MIS-C). Study Design: We performed a retrospective chart review of 113 patients with SARS-CoV-2 infection with or without MIS-C admitted at Children's Hospital of Michigan (CHM) from March to August 2020. Patient demographic details, laboratory data, imaging studies, echocardiography reports, and treatment data were collected. Results: Of the 92 patients included in the final analysis, 22 (24%) developed AKI with 8/22 (36%) developing stage 3 AKI. The prevalence of AKI was much higher in patients with MIS-C 15/28 (54%) vs. those with acute SARS-CoV-2 infection 7/64 (11%), (p < 0.001). Overall, when compared to patients without AKI, patients with AKI were older in age (11 vs. 6.5 years, p = 0.007), African American (86 vs. 58%, p = 0.028), had MIS-C diagnosis (68 vs. 19%, p < 0.001), required ICU admission (91 vs. 20%, p < 0.001), had cardiac dysfunction (63 vs. 16%, p < 0.001), required inotropic support (59 vs. 6%, p < 0.001) and had a greater elevation in inflammatory markers. In a multivariate analysis, requirement of inotropes [Odds Ratio (OR)-22.8, p < 0.001], African American race (OR-8.8, p = 0.023) and MIS-C diagnosis (OR-5.3, p = 0.013) were the most significant predictors for AKI. All patients had recovery of kidney function, and none required kidney replacement therapy. Conclusion: Children with acute SARS-CoV-2 infection and MIS-C are at risk for AKI, with the risk being significantly greater with MIS-C. The pathogenesis of AKI in acute SARS-CoV-2 infection appears to be a combination of both renal hypo-perfusion and direct renal parenchymal damage whereas in MIS-C, the renal injury appears to be predominantly pre-renal from cardiac dysfunction and capillary leak from a hyperinflammatory state. These factors should be considered by clinicians caring for these children with a special focus on renal protective strategies to aid in recovery and prevent additional injury to this high-risk subgroup.

New onset ANCA-associated vasculitis in an adolescent during an acute COVID-19 infection: a case report

BACKGROUND

SARS-CoV-2 has been found to be exquisitely adept at triggering autoimmunity and multiple new onset autoimmune diseases have been described as a post-infectious complication of COVID-19 infection in the adult population. Less has been described in the pediatric population, as infections are more likely to be asymptomatic and less severe. This case reports a previously healthy adolescent patient with new onset antineutrophil cytoplasmic autoantibody-associated vasculitis (AAV) diagnosed in the setting of acute COVID-19 infection.

CASE PRESENTATION

A previously healthy adolescent male was diagnosed with COVID-19 pneumonia after presenting with infectious symptoms of fever, cough, congestion, and shortness of breath. After worsening of disease, he was found to have pulmonary nodules, atypical for COVID-19. Further imaging and laboratory workup showed elevated inflammatory markers, negative infectious testing, and positive antineutrophil cytoplasmic antibodies (ANCA) diagnostic for AAV. He was treated with pulse dose steroids followed by a prolonged taper and rituximab. Symptoms resolved and laboratory abnormalities improved over time. At six-month follow-up, lesions were much improved, laboratory markers were within normal limits, and patient remained asymptomatic off medications.

CONCLUSIONS

This case is one of the first in the pediatric population to describe new onset AAV presenting with an acute, symptomatic COVID-19 infection. There is increasing evidence for COVID-19 induced autoimmunity in the pediatric population and pediatric care providers should be on high alert for new onset autoimmune disease in children afflicted by COVID-19.

The multisystem inflammatory syndrome in children and its association to SARS-CoV-2

PURPOSE OF REVIEW

Multisystem inflammatory syndrome in children (MIS-C)/pediatric inflammatory multisystem syndrome (PIMS) is a new and serious disease that occurs in temporal association with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We describe the clinical presentation, diagnosis, and treatment recommendations.

RECENT FINDING

To date, no randomized prospective studies have been published; recommendations are based on some observational studies, case reports, and expert opinions. The article provides an overview of the most important publications, presents the current results of the German Registry for PIMS and expert recommendations for treatment.

SUMMARY

MIS-C PIMS is a new syndrome that is associated with a variety of virus infections, and also with SARS-CoV-2. The main characteristics are fever, multiple organ dysfunction due to a hyper-inflammatory state. In particular, cardiac dysfunction and severe shock. A high proportion of patients require intensive medical care, but the absolute number of children with SARS-CoV-2 MIS-C is low. Medical therapy is based on pathophysiologic considerations and is not evidence-based. Immunoglobulins, steroids and biologics are used and lead to effective treatment. Therefore, the mortality rate is very low. Patients usually recover within days, sequelae are reported only in a minority of cases.

Late-Onset COVID-19-Related Multi-System Inflammatory Syndrome in a Middle-Aged Man

A 47-year-old man presented to the emergency department with persistent fever, chest pain and neck swelling, two months following a mild coronavirus disease 2019 (COVID-19) infection. He was found to have persistent fever, hypotension, cervical lymphadenitis, myocarditis, and acute kidney injury, collectively meeting the multi-system inflammatory syndrome criteria in adults (MIS-A). The patient responded well to methylprednisolone therapy and intravenous immunoglobulins with a complete clinical recovery. This case demonstrates that MIS-A can present as a delayed complication of COVID-19 infection.

Children with SARS-CoV-2 in the National COVID Cohort Collaborative (N3C)

IMPORTANCE

SARS-CoV-2.

OBJECTIVE

To determine the characteristics, changes over time, outcomes, and severity risk factors of SARS-CoV-2 affected children within the National COVID Cohort Collaborative (N3C).

DESIGN

Prospective cohort study of patient encounters with end dates before May 27th, 2021.

SETTING

45 N3C institutions.

PARTICIPANTS

Children <19-years-old at initial SARS-CoV-2 testing.

MAIN OUTCOMES AND MEASURES

Case incidence and severity over time, demographic and comorbidity severity risk factors, vital sign and laboratory trajectories, clinical outcomes, and acute COVID-19 vs MIS-C contrasts for children infected with SARS-CoV-2.

RESULTS

728,047 children in the N3C were tested for SARS-CoV-2; of these, 91,865 (12.6%) were positive. Among the 5,213 (6%) hospitalized children, 685 (13%) met criteria for severe disease: mechanical ventilation (7%), vasopressor/inotropic support (7%), ECMO (0.6%), or death/discharge to hospice (1.1%). Male gender, African American race, older age, and several pediatric complex chronic condition (PCCC) subcategories were associated with higher clinical severity (p ≤ 0.05). Vital signs (all p≤0.002) and many laboratory tests from the first day of hospitalization were predictive of peak disease severity. Children with severe (vs moderate) disease were more likely to receive antimicrobials (71% vs 32%, p<0.001) and immunomodulatory medications (53% vs 16%, p<0.001). Compared to those with acute COVID-19, children with MIS-C were more likely to be male, Black/African American, 1-to-12-years-old, and less likely to have asthma, diabetes, or a PCCC (p < 0.04). MIS-C cases demonstrated a more inflammatory laboratory profile and more severe clinical phenotype with higher rates of invasive ventilation (12% vs 6%) and need for vasoactive-inotropic support (31% vs 6%) compared to acute COVID-19 cases, respectively (p<0.03).

CONCLUSIONS

In the largest U.S. SARS-CoV-2-positive pediatric cohort to date, we observed differences in demographics, pre-existing comorbidities, and initial vital sign and laboratory test values between severity subgroups. Taken together, these results suggest that early identification of children likely to progress to severe disease could be achieved using readily available data elements from the day of admission. Further work is needed to translate this knowledge into improved outcomes.

Innate lymphoid cells and disease tolerance in SARS-CoV-2 infection

Risk of severe COVID-19 increases with age, is greater in males, and is associated with lymphopenia, but not with higher burden of SARS-CoV-2. It is unknown whether effects of age and sex on abundance of specific lymphoid subsets explain these correlations. This study found that the abundance of innate lymphoid cells (ILCs) decreases more than 7-fold over the human lifespan — T cell subsets decrease less than 2-fold — and is lower in males than in females. After accounting for effects of age and sex, ILCs, but not T cells, were lower in adults hospitalized with COVID-19, independent of lymphopenia. Among SARS-CoV-2-infected adults, the abundance of ILCs, but not of T cells, correlated inversely with odds and duration of hospitalization, and with severity of inflammation. ILCs were also uniquely decreased in pediatric COVID-19 and the numbers of these cells did not recover during follow-up. In contrast, children with MIS-C had depletion of both ILCs and T cells, and both cell types increased during follow-up. In both pediatric COVID-19 and MIS-C, ILC abundance correlated inversely with inflammation. Blood ILC mRNA and phenotype tracked closely with ILCs from lung. Importantly, blood ILCs produced amphiregulin, a protein implicated in disease tolerance and tissue homeostasis, and the percentage of amphiregulin-producing ILCs was higher in females than in males. These results suggest that, by promoting disease tolerance, homeostatic ILCs decrease morbidity and mortality associated with SARS-CoV-2 infection, and that lower ILC abundance accounts for increased COVID-19 severity with age and in males.

TBK1 and TNFRSF13B mutations and an autoinflammatory disease in a child with lethal COVID-19

Among children, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are typically mild. Here, we describe the case of a 3.5-year-old girl with an unusually severe presentation of coronavirus disease (COVID-19). The child had an autoinflammatory disorder of unknown etiology, which had been treated using prednisolone and methotrexate, and her parents were half cousins of Turkish descent. After 5 days of nonspecific viral infection symptoms, tonic-clonic seizures occurred followed by acute cardiac insufficiency, multi-organ insufficiency, and ultimate death. Trio exome sequencing identified a homozygous splice-variant in the gene TBK1, and a homozygous missense variant in the gene TNFRSF13B. Heterozygous deleterious variants in the TBK1 gene have been associated with severe COVID-19, and the variant in the TNFRSF13B gene has been associated with common variable immunodeficiency (CVID). We suggest that the identified variants, the autoinflammatory disorder and its treatment, or a combination of these factors probably predisposed to lethal COVID-19 in the present case.

Coronavirus Disease 2019-Associated PICU Admissions: A Report From the Society of Critical Care Medicine Discovery Network Viral Infection and Respiratory Illness Universal Study Registry

OBJECTIVES

To compare clinical characteristics and outcomes of children admitted to the PICU for severe acute respiratory syndrome coronavirus 2-related illness with or without multisystem inflammatory syndrome in children. The secondary objective was to identify explanatory factors associated with outcome of critical illness defined by a composite index of in-hospital mortality and organ system support requirement.

DESIGN

Retrospective cohort study.

SETTING

Thirty-eight PICUs within the Viral Infection and Respiratory Illness Universal Study registry from March 2020 to January 2021.

PATIENTS

Children less than 18 years with severe acute respiratory syndrome coronavirus 2-related illness with or without multisystem inflammatory syndrome in children.

MEASUREMENTS AND MAIN RESULTS

Of 394 patients, 171 (43.4%) had multisystem inflammatory syndrome in children. Children with multisystem inflammatory syndrome in children were more likely younger (2-12 yr vs adolescents; p < 0.01), Black (35.6% vs 21.9%; p < 0.01), present with fever/abdominal pain than cough/dyspnea (p < 0.01), and less likely to have comorbidities (33.3% vs 61.9%; p < 0.01) compared with those without multisystem inflammatory syndrome in children. Inflammatory marker levels, use of inotropes/vasopressors, corticosteroids, and anticoagulants were higher in multisystem inflammatory syndrome in children patients (p < 0.01). Overall mortality was 3.8% (15/394), with no difference in the two groups. Diagnosis of multisystem inflammatory syndrome in children was associated with longer duration of hospitalization as compared to nonmultisystem inflammatory syndrome in children (7.5 d[interquartile range, 5-11] vs 5.3 d [interquartile range, 3-11 d]; p < 0.01). Critical illness occurred in 164 patients (41.6%) and was more common in patients with multisystem inflammatory syndrome in children compared with those without (55.6% vs 30.9%; p < 0.01). Multivariable analysis failed to show an association between critical illness and age, race, sex, greater than or equal to three signs and symptoms, or greater than or equal to two comorbidities among the multisystem inflammatory syndrome in children cohort. Among nonmultisystem inflammatory syndrome in children patients, the presence of greater than or equal to two comorbidities was associated with greater odds of critical illness (odds ratio 2.95 [95% CI, 1.61-5.40]; p < 0.01).

CONCLUSIONS

This study delineates significant clinically relevant differences in presentation, explanatory factors, and outcomes among children admitted to PICU with severe acute respiratory syndrome coronavirus 2-related illness stratified by multisystem inflammatory syndrome in children.

Multisystem Inflammatory Syndrome in Children - Initial Therapy and Outcomes

BACKGROUND

The assessment of real-world effectiveness of immunomodulatory medications for multisystem inflammatory syndrome in children (MIS-C) may guide therapy.

METHODS

We analyzed surveillance data on inpatients younger than 21 years of age who had MIS-C and were admitted to 1 of 58 U.S. hospitals between March 15 and October 31, 2020. The effectiveness of initial immunomodulatory therapy (day 0, indicating the first day any such therapy for MIS-C was given) with intravenous immune globulin (IVIG) plus glucocorticoids, as compared with IVIG alone, was evaluated with propensity-score matching and inverse probability weighting, with adjustment for baseline MIS-C severity and demographic characteristics. The primary outcome was cardiovascular dysfunction (a composite of left ventricular dysfunction or shock resulting in the use of vasopressors) on or after day 2. Secondary outcomes included the components of the primary outcome, the receipt of adjunctive treatment (glucocorticoids in patients not already receiving glucocorticoids on day 0, a biologic, or a second dose of IVIG) on or after day 1, and persistent or recurrent fever on or after day 2.

RESULTS

A total of 518 patients with MIS-C (median age, 8.7 years) received at least one immunomodulatory therapy; 75% had been previously healthy, and 9 died. In the propensity-score-matched analysis, initial treatment with IVIG plus glucocorticoids (103 patients) was associated with a lower risk of cardiovascular dysfunction on or after day 2 than IVIG alone (103 patients) (17% vs. 31%; risk ratio, 0.56; 95% confidence interval [CI], 0.34 to 0.94). The risks of the components of the composite outcome were also lower among those who received IVIG plus glucocorticoids: left ventricular dysfunction occurred in 8% and 17% of the patients, respectively (risk ratio, 0.46; 95% CI, 0.19 to 1.15), and shock resulting in vasopressor use in 13% and 24% (risk ratio, 0.54; 95% CI, 0.29 to 1.00). The use of adjunctive therapy was lower among patients who received IVIG plus glucocorticoids than among those who received IVIG alone (34% vs. 70%; risk ratio, 0.49; 95% CI, 0.36 to 0.65), but the risk of fever was unaffected (31% and 40%, respectively; risk ratio, 0.78; 95% CI, 0.53 to 1.13). The inverse-probability-weighted analysis confirmed the results of the propensity-score-matched analysis.

CONCLUSIONS

Among children and adolescents with MIS-C, initial treatment with IVIG plus glucocorticoids was associated with a lower risk of new or persistent cardiovascular dysfunction than IVIG alone. (Funded by the Centers for Disease Control and Prevention.).

Treatment of Multisystem Inflammatory Syndrome in Children

BACKGROUND

Evidence is urgently needed to support treatment decisions for children with multisystem inflammatory syndrome (MIS-C) associated with severe acute respiratory syndrome coronavirus 2.

METHODS

We performed an international observational cohort study of clinical and outcome data regarding suspected MIS-C that had been uploaded by physicians onto a Web-based database. We used inverse-probability weighting and generalized linear models to evaluate intravenous immune globulin (IVIG) as a reference, as compared with IVIG plus glucocorticoids and glucocorticoids alone. There were two primary outcomes: the first was a composite of inotropic support or mechanical ventilation by day 2 or later or death; the second was a reduction in disease severity on an ordinal scale by day 2. Secondary outcomes included treatment escalation and the time until a reduction in organ failure and inflammation.

RESULTS

Data were available regarding the course of treatment for 614 children from 32 countries from June 2020 through February 2021; 490 met the World Health Organization criteria for MIS-C. Of the 614 children with suspected MIS-C, 246 received primary treatment with IVIG alone, 208 with IVIG plus glucocorticoids, and 99 with glucocorticoids alone; 22 children received other treatment combinations, including biologic agents, and 39 received no immunomodulatory therapy. Receipt of inotropic or ventilatory support or death occurred in 56 patients who received IVIG plus glucocorticoids (adjusted odds ratio for the comparison with IVIG alone, 0.77; 95% confidence interval [CI], 0.33 to 1.82) and in 17 patients who received glucocorticoids alone (adjusted odds ratio, 0.54; 95% CI, 0.22 to 1.33). The adjusted odds ratios for a reduction in disease severity were similar in the two groups, as compared with IVIG alone (0.90 for IVIG plus glucocorticoids and 0.93 for glucocorticoids alone). The time until a reduction in disease severity was similar in the three groups.

CONCLUSIONS

We found no evidence that recovery from MIS-C differed after primary treatment with IVIG alone, IVIG plus glucocorticoids, or glucocorticoids alone, although significant differences may emerge as more data accrue. (Funded by the European Union's Horizon 2020 Program and others; BATS ISRCTN number, ISRCTN69546370.).

COVID-19 Infection in Spinal Muscular Atrophy Associated with Multisystem Inflammatory Syndrome

The coronavirus disease-2019 (COVID-19) is usually less severe and less prevalent in the pediatric population. Children with preexisting conditions such as neuromuscular impairments and chronic lung disease are more susceptible to COVID-19 and may incur several complications with a poor outcome. We present a case report of a 3-year-old-female with generalized hypotonia and respiratory failure due to spinal muscular atrophy who tested positive for COVID-19 and developed multisystem inflammatory syndrome that was treated with intravenous immunoglobulin and tocilizumab and subsequently died. The report highlights the importance of close surveillance, the use of protective measures during hospital visits, early testing, and diagnosis of COVID-19 in children with neurological disorders.

New Onset of Hepatic Steatosis Post-Severe Multisystem Inflammatory Syndrome in Children (MIS-C): A Case Report

The emergence of Multisystem Inflammatory Syndrome (MIS-C) following SARS-CoV-2 infection in children and adolescents provided a new diagnostic and management challenge as there is limited knowledge about this condition and its natural history. In existing literature on MIS-C, there are currently no data about long-term outcomes. We report the case of a 14-year-old boy, with no significant past medical history, who presented a condition of multiorgan dysfunction due to MIS-C, after a SARS CoV-2 infection, and subsequent clinical-laboratory signs of hepatic steatosis at short-term follow-up. The case suggests how hepatic steatosis may be a possible sequela following SARS-CoV-2 infection, MIS-C and its medical treatment. Therefore, a close and long-term follow-up is needed to establish the pathophysiology and the evolution of this condition in patients following MIS-C.

COVID-19 and social distancing among children and adolescents in Brazil

OBJECTIVE

To estimate the prevalence of SARS-CoV-2 antibodies and the adherence to measures of social distancing in children and adolescents studied in three national surveys conducted in Brazil between May-June 2020.

METHODS

Three national serological surveys were conducted in 133 sentinel cities located in all 27 Federative Units. Multistage probability sampling was used to select 250 individuals per city. The total sample size in age ranges 0-9 and 10-19 years old are of 4,263 and 8,024 individuals, respectively. Information on children or adolescents was gathered with a data collection app, and a rapid point-of-case test for SARS-CoV-2 was conducted on a finger prick blood sample.

RESULTS

The adjusted prevalence of antibodies was 2.9% (2.2-3.6) among children 0-9 years, 2.2% (1.8-2.6) among adolescents 10-19 years, and 3.0% (2.7-3.3) among adults 20+years. Prevalence of antibodies was higher among poor children and adolescents compared to those of rich families. Adherence to social distancing measures was seen in 72.4% (71.9-73.8) of families with children, 60.8% (59.6-61.9) for adolescents, and 57.4% (56.9-57.8) for adults. For not leaving the house except for essential matters the proportions were 81.7% (80.5-82.9), 70.6% (69.6-61.9), and 65.1% (64.7-65.5), respectively. Among children and adolescents, social distancing was strongly associated with socioeconomic status, being much higher in the better-off families.

CONCLUSIONS

The prevalence of antibodies against SARS-CoV-2 showed comparable levels among children, adolescents, and adults. Adherence to social distancing measures was more prevalent in children, followed by adolescents. There were important socioeconomic differences in the adherence to social distancing among children and adolescents.

Similarities and Differences Between COVID-19-Related Multisystem Inflammatory Syndrome in Children and Kawasaki Disease

In December 2019, the first case of coronavirus disease (COVID-19) was first reported in Wuhan, China. As of March 2021, there were more than 120 million confirmed cases of COVID-19 and 2.7 million deaths. The COVID-19 mortality rate in adults is around 1-5%, and only a small proportion of children requires hospitalization and intensive care. Recently, an increasing number of COVID-19 cases in children have been associated with a new multisystem inflammatory syndrome. Its clinical features and laboratory characteristics are similar to those of Kawasaki disease (KD), KD shock syndrome, and toxic shock syndrome. However, this new disorder has some distinct clinical features and laboratory characteristics. This condition, also known as multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19, has been observed mostly in Europe and the United States. This emerging phenomenon has raised the question of whether this disorder is KD triggered by SARS-CoV-2 or a syndrome characterized by multisystem inflammation that mimics KD. This narrative review is to discuss the differences between MIS-C and KD with the aim of increasing pediatricians' awareness of this new condition and guide them in the process of differential diagnosis.

COVID-19 associated Multisystem Inflammatory Syndrome in Children (MIS-C) guidelines; revisiting the Western New York approach as the pandemic evolves

Multisystem inflammatory syndrome of children (MIS-C) continues to be a highly concerning diagnosis in those recently infected with SARS-CoV-2. The diagnosis of MIS-C cases will likely become even more challenging as vaccine uptake and natural immunity in previously infected persons leads to lower circulating rates of SARS-CoV-2 infection and will make cases sporadic. Febrile children presenting with cardiac dysfunction, symptoms overlapping Kawasaki disease or significant gastrointestinal complaints warrant a thorough screen in emergency departments, urgent care centers, and outpatient pediatric or family medicine practices. An increased index of suspicion and discussion regarding higher level of care (transferring to pediatric tertiary care centers or to intensive care) continues to be recommended. Herein we outline a broad approach with a multidisciplinary team for those meeting the case definition and believe such an approach is crucial for successful outcomes.

Multisystem inflammatory syndrome in children with COVID-19

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a dangerous pediatric complication of COVID-19.

OBJECTIVE

The purpose of this review article is to provide a summary of the diagnosis and management of MIS-C with a focus on management in the acute care setting.

DISCUSSION

MIS-C is an inflammatory syndrome which can affect nearly any organ system. The most common symptoms are fever and gastrointestinal symptoms, though neurologic and dermatologic findings are also well-described. The diagnosis includes a combination of clinical and laboratory testing. Patients with MIS-C will often have elevated inflammatory markers and may have an abnormal electrocardiogram or echocardiogram. Initial treatment involves resuscitation with careful assessment for cardiac versus vasodilatory shock using point-of-care ultrasound. Treatment should include intravenous immunoglobulin, anticoagulation, and consideration of corticosteroids. Interleukin-1 and/or interleukin-6 blockade may be considered for refractory cases. Aspirin is recommended if there is thrombocytosis or Kawasaki disease-like features on echocardiogram. Patients will generally require admission to an intensive care unit.

CONCLUSION

MIS-C is a condition associated with morbidity and mortality that is increasingly recognized as a potential complication in pediatric patients with COVID-19. It is important for emergency clinicians to know how to diagnose and treat this disorder.

Multisystemic Inflammatory Syndrome and Thrombotic Microangiopathy as Complications of COVID-19 in a Child: A Case Report

Clinical presentations of the novel coronavirus (SARS-CoV-2) infection are quite varied, ranging from asymptomatic conditions to potentially fatal disease. The kidney is one of the affected targets of coronavirus disease (COVID-19) complications, and renal dysfunction is a significant prognostic factor for mortality. This report describes a series of clinical complications in a previously healthy child who developed nephritic syndrome with a concomitant SARS-CoV-2 infection. These complications include acute kidney injury that progressed to chronicity, multisystemic inflammatory syndrome, Kawasaki-like syndrome, and thrombotic microangiopathy.

Editorial: COVID-19 and Multisystem Inflammatory Syndrome in Children (MIS-C)

In early 2020, at the beginning of the coronavirus disease 2019 (COVID-19) pandemic due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rare cases were reported in children and adolescents of multisystem inflammatory syndrome in children (MIS-C). MIS-C is characterized by fever, systemic inflammation, and multiorgan dysfunction and usually presents late in SARS-CoV-2 infection. Since May 2020, the Centers for Disease Control and Prevention (CDC) has recorded all reported cases of COVID-19 and MIS-C in children and adolescents in the USA. In April 2021, the American College of Rheumatology (ACR) revised its clinical guidelines for diagnosing and managing hyperinflammation and MIS-C. There are several challenges ahead for preventing, diagnosing, and managing MIS-C, particularly following the rapid emergence of new strains of SARS-CoV-2. This Editorial aims to present an update on the current status of the clinical presentation, diagnosis, and management of MIS-C and includes some updates from population studies and clinical guidelines.

Characteristics and Outcomes of Pediatric COVID-19 Patients in Osaka, Japan

The epidemiological information on characteristics, in-hospital treatments, and outcomes of the coronavirus disease 2019 (COVID-19) among pediatric patients has not been fully evaluated in Japan. This was a retrospective observational study conducted in the Osaka Prefecture, Japan, and we enrolled laboratory-confirmed COVID-19 patients aged ≤19 years old from January to November in 2020. Of 14,846 COVID-19 eligible patients, 1240 pediatric patients (8.4%) were registered during the study period; 329 were children aged 0–9 years (26.5%) and 911 were adolescents aged 10–19 years (73.5%). The majority of the patients exhibited mild symptoms at diagnosis (872, 70.3%), some were asymptomatic (296, 23.9%). Cluster infections occurred in child-care facilities (26, 7.9%) among children and in universities (27, 3.0%) and schools (18, 2.0%) among adolescents. The number of close-contact cases was 260 (69.0%) in children and 459 (50.4%) in adolescents. Sixty of the children (18.2%) and 90 of the adolescents (9.9%) were hospitalized. One patient received mechanical ventilation, and none underwent extracorporeal membrane oxygenation. One patient was admitted to the intensive care unit; there were no deaths. These results are useful for recognizing the clinical course from transmission route to outcomes of this infection in pediatric patients.

Multisystem inflammatory syndrome in children during the coronavirus disease pandemic of 2019: a review of clinical features and acute phase management

The current coronavirus disease of 2019 (COVID-19) pandemic has presented unique health challenges in the pediatric population. Compared to adults, the most significant change in viral disease manifestation is encompassed by the multisystem inflammatory syndrome in children (MIS-C). MIS-C is a new inflammatory syndrome which develops 2–4 weeks after COVID-19 exposure, with evidence suggesting it is a post-infectious immune reaction. We describe its epidemiology, pathophysiology, diagnosis (which varies based on definition used) and treatment options based on published recommendations. A systematic literature search we conducted through MEDLINE yielded 518 abstracts and identified five studies that reported more than 100 cases of MIS-C and their mortality. Most cases developed multiorgan dysfunction, including cardiovascular, dermatologic, neurological, renal, and respiratory issues, and required intensive care unit (ICU) admission. Many patients admitted to the ICU needed inotrope support and invasive mechanical ventilation, and the most severe cases required extracorporeal membrane oxygenation support. Most clinicians treated MIS-C with intravenous immunoglobulin, systemic steroids, and biological therapies. Overall mortality was low (2–3%) in all studies. Further research is needed to: understand if early intervention can prevent its progression; optimize its treatment; and improve outcomes of this new syndrome for the patients who develop MIS-C.

6-month multidisciplinary follow-up and outcomes of patients with paediatric inflammatory multisystem syndrome (PIMS-TS) at a UK tertiary paediatric hospital: a retrospective cohort study

BACKGROUND

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) is a new, rare, post-infectious complication of SARS-CoV-2 infection in children. We aimed to describe the 6-month outcomes of PIMS-TS.

METHODS

This retrospective cohort study comprised children (aged <18 years) who fulfilled the UK Royal College of Paediatrics and Child Health (RCPCH) diagnostic criteria for PIMS-TS and were admitted to Great Ormond Street Hospital (London, UK) between April 4 and Sept 1, 2020. Patients were followed up by a multidisciplinary team of specialists at 6 weeks and 6 months after admission. Biochemical and functional outcomes were analysed.

FINDINGS

46 children were included in this study. The median age at presentation was 10·2 years (IQR 8·8-13·3), 30 (65%) patients were male and 16 (35%) were female, 37 (80%) were from minority ethnic groups, and eight (17%) had pre-existing comorbidities. All patients had elevated markers of systemic inflammation at baseline. None of the patients died. By 6 months, systemic inflammation was resolved in all but one patient. 38 (90%) of 42 patients who had positive SARS-CoV-2 IgG antibodies within 6 weeks of admission remained seropositive at 6 months. Echocardiograms were normal in 44 (96%) of 46 patients by 6 months, and gastrointestinal symptoms that were reported in 45 (98%) of 46 patients at onset were present in six (13%) of 46 patients at 6 months. Renal, haematological, and otolaryngological findings largely resolved by 6 months. Although minor abnormalities were identified on neurological examination in 24 (52%) of 46 patients at 6 weeks and in 18 (39%) of 46 at 6 months, we found minimal functional impairment at 6 months (median Expanded Disability Status Scale score 0 [IQR 0-1]). Median manual muscle test-8 scores improved from 53 (IQR 43-64) during hospital admission to 80 (IQR 68-80) at 6 months, but 18 (45%) of 40 patients showed 6-min walk test results below the third centile for their age or sex at 6 months. PedsQL responses revealed severe emotional difficulties at 6 months (seven [18%] of 38 by parental report and eight [22%] of 38 by self report). 45 (98%) of 46 patients were back in full-time education (virtually or face to face) by 6 months.

INTERPRETATION

Despite initial severe illness, few organ-specific sequelae were observed at 6 months. Ongoing concerns requiring physical re-conditioning and mental health support remained, and physiotherapy assessments revealed persisting poor exercise tolerance. Longer-term follow-up will help define the extended natural history of PIMS-TS.

FUNDING

None.

Multisystem inflammatory syndrome in adults: A rare sequela of SARS-CoV-2 infection

Multisystem inflammatory syndrome in adults (MIS-A) came to attention back in June 2020, when the United States Center for Disease Control and Prevention (CDC) received initial reports regarding patients who had presented delayed and multisystem involvement of the disease, with clinical course resembling multisystem inflammatory syndrome in children (MIS-C). This study introduces a case of MIS-A, where the patient presented 3 weeks after initial COVID-19 exposure. His clinical course was consistent with the working definition of MIS-A as specified by the CDC. Aggressive supportive care in the intensive care unit, utilization of advanced heart failure devices, and immunomodulatory therapeutics (high-dose steroids, anakinra, intravenous immunoglobulin) led to clinical recovery. Management of MIS-A is a topic of ongoing research and needs more studies to elaborate on treatment modalities and clinical predictors.

COVID-19-associated multisystem inflammatory syndrome in children (MIS-C) presenting as appendicitis with shock

Multisystem inflammatory syndrome in children (MIS-C) is an identified complication of the COVID-19 infection. A common presentation of both COVID-19 and MIS-C is acute abdominal pain, sometimes mimicking appendicitis. We report two cases of patients initially diagnosed with appendicitis who either presented with or developed signs of shock and were found to have MIS-C. An 8-year-old girl who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase-polymerase chain reaction (RT-PCR) presented with fever, abdominal pain, and shock with ultrasound findings consistent with acute appendicitis. After being treated for MIS-C, she underwent appendectomy and improved. Final pathology was consistent with acute appendicitis. A 9-year-old girl who tested negative for COVID RT-PCR presented with uncomplicated appendicitis and underwent laparoscopic appendectomy, but developed post-operative fever and shock. Antibody testing was positive and she responded to treatment for MIS-C. Histology showed lymphohistiocytic inflammation within the muscularis propria, mesoappendix and serosa without the typical neutrophil-rich inflammation and mucosal involvement of acute appendicitis. The diagnosis was MIS-C, not appendicitis. Given the new reality of the COVID-19 pandemic, pediatric surgeons must be aware of MIS-C as a possible diagnosis and should understand the diagnostic criteria and current treatment guidelines.