One-Year Outcomes of Critical Care Patients Post-COVID-19 Multisystem Inflammatory Syndrome in Children

Postacute Sequelae of SARS-CoV-2 in Children

The coronavirus disease 2019 (COVID-19) pandemic has caused significant medical, social, and economic impacts globally, both in the short and long term. Although most individuals recover within a few days or weeks from an acute infection, some experience longer lasting effects. Data regarding the postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection (PASC) in children, or long COVID, are only just emerging in the literature. These symptoms and conditions may reflect persistent symptoms from acute infection (eg, cough, headaches, fatigue, and loss of taste and smell), new symptoms like dizziness, or exacerbation of underlying conditions. Children may develop conditions de novo, including postural orthostatic tachycardia syndrome, myalgic encephalomyelitis/chronic fatigue syndrome, autoimmune conditions and multisystem inflammatory syndrome in children. This state-of-the-art narrative review provides a summary of our current knowledge about PASC in children, including prevalence, epidemiology, risk factors, clinical characteristics, underlying mechanisms, and functional outcomes, as well as a conceptual framework for PASC based on the current National Institutes of Health definition. We highlight the pediatric components of the National Institutes of Health-funded Researching COVID to Enhance Recovery Initiative, which seeks to characterize the natural history, mechanisms, and long-term health effects of PASC in children and young adults to inform future treatment and prevention efforts. These initiatives include electronic health record cohorts, which offer rapid assessments at scale with geographical and demographic diversity, as well as longitudinal prospective observational cohorts, to estimate disease burden, illness trajectory, pathobiology, and clinical manifestations and outcomes.

One-Year Follow-Up Results of MIS-C Patients with Coronary Artery Involvement: A Multi-center Study

Multisystem inflammatory syndrome (MIS-C) in children is a rare complication of SARS-CoV-2 infection. Knowing the course of the affected or unaffected coronary arteries in the patients under follow-up is important in terms of defining the long-term prognosis of the disease and determining the follow-up plan. This is a multicenter and retrospective study. The data were obtained from nine different centers. Between May 2020 and August 2022, 68 of 790 patients had coronary artery involvement. One-year echocardiographic data of 67 of 789 MIS-C patients with coronary artery involvement were analyzed. Existing pathologies of the coronary arteries were grouped as increased echogenicity, dilatation and aneurysm according to Z scores, and their changes over a 1-year period were determined. The data of all three groups are defined as frequency. SPSS Statistics version 22 was used to evaluate the data. In our study, aneurysm was observed in 16.4%, dilatation in 68.7% and increased echogenicity in 13.4% of the patients. All of the patients with involvement in the form of increased echogenicity recovered without sequelae by the end of the first month. No progression to aneurysm was observed in any of the patients with dilatation. No new-onset involvement was observed in patients with previously healthy coronary arteries during the convalescent period. In addition, from the sixth month follow-up period, there was no worsening in the amount of dilatation in any of the patients. At least 94% of the patients who completed the 12th month control period returned to normal.

Six-month outcome of multisystem inflammatory syndrome with persistent neutropenia in neonate: A case report and review of literature

Multisystem inflammatory syndrome in Children (MIS-C) is a postinfectious immune mediated complications seen in children and develop after 4-6 weeks of severe acute respiratory syndrome coronavirus -2 (SARS-CoV-2) infection, however, it is rare in neonates. The index case was admitted at day 19 of life with complaints of fever, loose stools and rash. Baby was discharged after 1 weeks with diagnosis of Multisystem inflammatory syndrome with persistent neutropenia. We follow up the case at 6 weeks, 12 weeks and 6 months of life. Growth, neurodevelopment and hematological parameters were monitored over time. We are reporting this follow up of MIS-N with persistent neutropenia because it is very rare, organ specific manifestations, effect on growth & development is unknown and needs to be reported. Improvement in hematological parameters and markers of coagulopathy & systemic inflammation required months before they return to baseline. There are no long-term sequelae on growth and neurodevelopment.

Evaluation of late cardiac effects after multisystem inflammatory syndrome in children

Introduction

Multisystem inflammatory syndrome in children (MIS-C) is associated with important cardiovascular morbidity during the acute phase. Follow-up shows a swift recovery of cardiac abnormalities in most patients. However, a small portion of patients has persistent cardiac sequelae at mid-term. The goal of our study was to assess late cardiac outcomes of MIS-C.

Methods

A prospective observational multicenter study was performed in children admitted with MIS-C and cardiac involvement between April 2020 and March 2022. A follow-up by NT-proBNP measurement, echocardiography, 24-h Holter monitoring, and cardiac MRI (CMR) was performed at least 6 months after MIS-C diagnosis.

Results

We included 36 children with a median age of 10 (8.0-11.0) years, and among them, 21 (58%) were girls. At diagnosis, all patients had an elevated NT-proBNP, and 39% had a decreased left ventricular ejection fraction (LVEF) (<55%). ECG abnormalities were present in 13 (36%) patients, but none presented with arrhythmia. Almost two-thirds of patients (58%) had echocardiographic abnormalities such as coronary artery dilation (20%), pericardial effusion (17%), and mitral valve insufficiency (14%). A decreased echocardiographic systolic left ventricular (LV) function was detected in 14 (39%) patients. A follow-up visit was done at a mean time of 12.1 (±5.8) months (range 6-28 months). The ECG normalized in all except one, and no arrhythmias were detected on 24-h Holter monitoring. None had persistent coronary artery dilation or pericardial effusion. The NT-proBNP level and echocardiographic systolic LV function normalized in all patients, except for one, who had a severely reduced EF. The LV global longitudinal strain (GLS), as a marker of subclinical myocardial dysfunction, decreased (z < -2) in 35%. CMR identified one patient with severely reduced EF and extensive myocardial fibrosis requiring heart transplantation. None of the other patients had signs of myocardial scarring on CMR.

Conclusion

Late cardiac outcomes after MIS-C, if treated according to the current guidelines, are excellent. CMR does not show any myocardial scarring in children with normal systolic LV function. However, a subgroup had a decreased GLS at follow-up, possibly as a reflection of persistent subclinical myocardial dysfunction.

Neurocognitive, Psychosocial, and Quality of Life Outcomes After Multisystem Inflammatory Syndrome in Children Admitted to the PICU

OBJECTIVES

To investigate neurocognitive, psychosocial, and quality of life (QoL) outcomes in children with Multisystem Inflammatory Syndrome in Children (MIS-C) seen 3-6 months after PICU admission.

DESIGN

National prospective cohort study March 2020 to November 2021.

SETTING

Seven PICUs in the Netherlands.

PATIENTS

Children with MIS-C (0-17 yr) admitted to a PICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Children and/or parents were seen median (interquartile range [IQR] 4 mo [3-5 mo]) after PICU admission. Testing included assessment of neurocognitive, psychosocial, and QoL outcomes with reference to Dutch pre-COVID-19 general population norms. Effect sizes (Hedges' g ) were used to indicate the strengths and clinical relevance of differences: 0.2 small, 0.5 medium, and 0.8 and above large. Of 69 children with MIS-C, 49 (median age 11.6 yr [IQR 9.3-15.6 yr]) attended follow-up. General intelligence and verbal memory scores were normal compared with population norms. Twenty-nine of the 49 followed-up (59%) underwent extensive testing with worse function in domains such as visual memory, g = 1.0 (95% CI, 0.6-1.4), sustained attention, g = 2.0 (95% CI 1.4-2.4), and planning, g = 0.5 (95% CI, 0.1-0.9). The children also had more emotional and behavioral problems, g = 0.4 (95% CI 0.1-0.7), and had lower QoL scores in domains such as physical functioning g = 1.3 (95% CI 0.9-1.6), school functioning g = 1.1 (95% CI 0.7-1.4), and increased fatigue g = 0.5 (95% CI 0.1-0.9) compared with population norms. Elevated risk for posttraumatic stress disorder (PTSD) was seen in 10 of 30 children (33%) with MIS-C. Last, in the 32 parents, no elevated risk for PTSD was found.

CONCLUSIONS

Children with MIS-C requiring PICU admission had normal overall intelligence 4 months after PICU discharge. Nevertheless, these children reported more emotional and behavioral problems, more PTSD, and worse QoL compared with general population norms. In a subset undergoing more extensive testing, we also identified irregularities in neurocognitive functions. Whether these impairments are caused by the viral or inflammatory response, the PICU admission, or COVID-19 restrictions remains to be investigated.

Short to midterm follow-up of multi-system inflammatory syndrome in children with special reference to cardiac involvement

OBJECTIVES

We aim to describe the early and upto 16 months follow-up of post-coronavirus disease (COVID), multi-system inflammatory syndrome in children (MIS-C), with special reference to cardiac involvement.

STUDY DESIGN

This cohort non-interventional descriptive study included patients <18 years admitted between May, 2020 and April, 2021. Based on underlying similarities, children were classified as post-COVID MIS-C with overlapping Kawasaki Disease, MIS-C with no overlapping Kawasaki Disease, and MIS-C with shock. Post-discharge, patients were followed at 1, 3, 6, 12, and 16 months.

RESULTS

Forty-one patients predominantly males (73%), at median age of 7 years (range 0.2-16 years) fulfilled the World Health Organisation criteria for MIS-C. Cardiac involvement was seen in 15 (36.5%); impaired left ventricle (LV) function in 5 (12.2%), coronary artery involvement in 10 (24.4%), pericardial effusion in 6 (14.6%) patients, and no arrhythmias. There were two hospital deaths (4.9%), both in MIS-C shock subgroup (2/10, 20%). At 1 month, there was persistent LV dysfunction in 2/5, coronary artery abnormalities in 7/10, and pericardial effusion resolved completely in all patients. By 6 months, LV function returned to normal in all but coronary abnormalities persisted in two patients. At last follow-up (median 9.8 months, interquartile range 2-16 months), in 36/38 (94.7%) patients, coronary artery dilatation was persistent in 2 (20%) patients.

CONCLUSIONS

Children with MIS-C have a good early outcome, though MIS-C with shock can be life-threatening subgroup in a resource-constrained country setting. On midterm follow-up, there is normalisation of LV function in all and recovery of coronary abnormalities in 80% of patients.

Long-Term Cardiovascular Outcomes of Multisystem Inflammatory Syndrome in Children Associated with COVID-19 Using an Institution Based Algorithm

Cardiovascular involvement is a major cause of inpatient and intensive care unit morbidity related to Multisystem inflammatory syndrome in children (MIS-C). The objective of this study was to identify long-term cardiovascular manifestations of MIS-C. We included 80 consecutive patients admitted to the intensive care unit with MIS-C who were evaluated for a year in our follow-up clinic using an institution protocol. The outcome measures were cardiac biomarkers (troponin and BNP), electrocardiogram changes, echocardiographic findings cardiovascular magnetic resonance (CMR) and graded-exercise stress test (GXT) findings. The cohort included patients aged between 6 months and 17 years (median 9 years; 48.8% females). At the peak of the disease 81.3% had abnormal BNP and 58.8% had troponin leak which reduced to 33.8% and 18.8% respectively at discharge with complete normalization by 6 weeks post-discharge. At admission 33.8% had systolic dysfunction, which improved to 11.3% at discharge with complete resolution by 2 weeks. Coronary artery abnormalities were seen in 17.5% during the illness with complete resolution by 2 weeks post discharge except one (1.9%) with persistent giant aneurysm at 1 year-follow up. CMR was performed at 6 months in 23 patient and demonstrated 4 patients with persistent late gadolinium enhancement (17.4%). Normal exercise capacity with no ectopy was seen in the 31 qualifying patients that underwent a GXT. There is significant heterogeneity in the cardiovascular manifestations of MIS-C. Although majority of the cardiovascular manifestations resolve within 6 weeks, diastolic dysfunction, CAA and myocardial scar may persist in a small subset of patients warranting a structured long-term follow-up strategy.

Physiologic profile associated with severe multisystem inflammatory syndrome in children: a retrospective study

OBJECTIVE

The purpose of this study was to describe the clinical presentation and physiologic profile of individuals with varying degrees of severity of multisystem inflammatory syndrome in children (MIS-C).

METHODS

We performed a retrospective study of children diagnosed with MIS-C admitted to a single quaternary children's hospital from May 2020 to April 2021. We created an MIS-C severity score using the following parameters: hospital admission status (e.g., floor vs intensive care unit), need for inotropic or vasoactive medications, and need for mechanical ventilation. Univariate and multivariate analyses were performed to associate risk factors corresponding to the MIS-C severity score.

RESULTS

The study included 152 children who were followed for 14 days post hospital admission. A stepwise forward selection process identified seven physiologic variables associated with "severe" MIS-C according to a logistic regression. Specifically, a combination of elevated creatinine (p = 0.013), international normalized ratio (p = 0.002), brain natriuretic peptide (p = 0.001), white blood cell count (p = 0.009), ferritin (p = 0.041), respiratory rate (p = 0.047), and decreased albumin (p = 0.047) led to an excellent discrimination between mild versus severe MIS-C (AUC = 0.915).

CONCLUSION

This study derived a physiologic profile associated with the stratification of MIS-C severity.

IMPACT

Based on a cohort of 152 individuals diagnosed with MIS-C, this study derived a nomenclature that stratifies the severity of MIS-C. Investigated demographic, presentational vital signs, and blood analytes associated with severity of illness. Identification of a multivariate physiologic profile that strongly associates with MIS-C severity. This model allows the care team to recognize patients likely to require a higher level of intensive care.

Multisystem inflammatory syndrome in children in Singapore

Introduction: Multisystem inflammatory syndrome in children (MIS-C) is a rare inflammatory syndrome with multisystem involvement affecting children exposed to COVID-19. This condition is rarely reported in East Asia and was not detected in Singapore until 2021. We present 12 cases of MIS-C diagnosed in KK Women’s and Children’s Hospital (KKH) from October 2021 to December 2021. Method: We conducted an observational study on cases fulfilling the Singapore Ministry of Health criteria for MIS-C from January 2020 to December 2021 in KKH. Medical records were reviewed to obtain information on clinical presentation, disease course, treatment received and outcomes. Results: In the 12 cases detected, the median age was 7.50 years (interquartile range 4.00–9.25); 8 were male. All patients had mucocutaneous symptoms similar to Kawasaki disease. Other commonly involved systems were: haematological (coagulopathy 100%, lymphopaenia 91.70% and thrombocytopaenia 75.00%), gastrointestinal (75.00%) and cardiovascular (83.30%). Six patients (50.00%) had shock and were admitted to the intensive care unit. The majority of patients received treatment within 2 days of hospitalisation with intravenous immunoglobulin (IVIg) and steroids. All survived; the majority had normal echocardiograms and no long-term organ sequelae at 6 months post-discharge. Conclusion: MIS-C emerged in Singapore as the incidence of COVID-19 in the community increased in 2021. The clinical presentation of our patients is similar to earlier reports, with some significant differences from Kawasaki disease. Multidisciplinary management, timely diagnosis, and early initiation of treatment with IVIg and steroids likely contributed to comparatively good outcomes. Our cases highlight the need for continued awareness of MIS-C among physicians, and surveillance of its incidence, short- and long-term outcomes. Keywords: COVID-19, children, MIS-C, inflammation, paediatrics

Longitudinal Cardiac Outcomes of Multisystem Inflammatory Syndrome in Children: A Systematic Review and Meta-Analysis

There is a paucity of longitudinal data on cardiac outcomes in multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19. We aimed to investigate the longitudinal cardiovascular outcomes in MIS-C. PubMed and EMBASE were searched through May 2022. Observational studies were included, reporting mid-term (≥ 3 months) outcomes in children (aged < 21) with MIS-C. Data were extracted by two researchers. Longitudinal outcomes were synthesized by a one-group meta-analysis using a random-effects model. Eleven studies with a follow-up period (3 months to 1 year) were identified, including 547 MIS-C patients. The mortality was 2.5% (95% CI 1.3-4.9). The majority of left ventricular (LV) systolic dysfunction present in 46.8% (95% CI 32.7-61.3) in the acute phase resolved by 3 months, and the prevalence of LV systolic dysfunction was 1.7% (95% CI 0.5-5.7) and 2.1% (95% CI 0.8-5.4) at 3 month and 6 month follow-up, respectively. Additionally, the persistent LV systolic dysfunction in the small population was mild. However, coronary abnormalities such as coronary artery dilatation or aneurysms, seen in 23.7% (95% CI 17.7-31.1) at baseline, persisted in 4.7% (95% CI 1.5-14.3) at 3 months and 5.2% (95% CI 3.0-8.9) at 6 months. Mitral regurgitation (MR), which was observed in 56.6% (95% CI 27.7-81.6) at baseline, also persisted in 7.5% at 6 months. In conclusion, our study demonstrated largely favorable cardiac outcomes, suggesting resolution of LV systolic dysfunction in the majority of cases. However, coronary abnormalities and MR persisted in a subset of patients at mid-term follow-up.

SARS-CoV-2 variants and the risk of pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 among children in Germany

Purpose

To investigate the relationship between the risk of pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in children and the predominance of different SARS-CoV-2 variants of concern (VOC) over time.

Methods

In relation to the Alpha, Delta, and Omicron VOC phases of the pandemic, the risk of developing PIMS-TS was calculated by analyzing data for rtPCR-confirmed SARS-CoV-2 infections reported to the German statutory notification system, along with data captured by a separate, national PIMS-TS registry. Both overall infection rates and age group-specific ratios of PIMS-TS during the different pandemic phases were calculated using the Alpha period as the baseline.

Results

The PIMS-TS rate changed significantly over time. When the Alpha VOC was dominant [calendar week (CW) 11 in March–CW 31 in August 2021], the PIMS-TS rate was 6.19 [95% confidence intervals (95% CI) 5.17, 7.20]. When Delta prevailed (CW 32 in August 2021–CW 4 in January 2022), the rate decreased to 1.68 (95% CI 1.49, 1.87). During the Omicron phase (CW 5 in January–CW 16 in April 2022), the rate fell further to 0.89 (95% CI 0.79, 1.00). These changes correspond to a decreased PIMS-TS rate of 73% (rate ratio 0.271, 95% CI 0.222; 0.332) and 86% (rate ratio 0.048, 95% CI 0.037; 0.062), respectively, in comparison to the Alpha period. Rate ratios were nearly identical for all age groups.

Conclusion

The data strongly suggest an association between the risk for PIMS-TS and the prevailing VOC, with highest risk related to Alpha and the lowest to Omicron. Given the uniformity of the decreased risk across age groups, vaccination against SARS-CoV-2 does not appear to have a significant impact on the risk of children developing PIMS-TS.

Clinico-Laboratory Profile, Intensive Care Needs and Short-Term Outcome of Multisystem Inflammatory Syndrome in Children (MIS-C): Experience during First and Second Waves from North India

OBJECTIVES

To describe the clinico-laboratory profile, intensive care needs and outcome of multisystem inflammatory syndrome in children (MIS-C) during the first and second waves.

METHODOLOGY

This retrospective study was conducted in the paediatric emergency and paediatric intensive care unit (PICU) of a tertiary care teaching hospital in North India involving 122 children with MIS-C admitted during the first wave (September 2020-January 2021, n = 40) and second wave (February 2021-September 2021, n = 82) of coronavirus disease 2019 (COVID-19).

RESULTS

The median (interquartile range) age was 7 (4-10) years and 67% were boys. Common manifestations included fever (99%), abdominal symptoms (81%), rash (66%) and conjunctival injection (65%). Elevated C-reactive protein (97%), D-dimer (89%), procalcitonin (80%), IL-6 (78%), ferritin (56%), N-terminal pro B-type natriuretic peptide (84%) and positive severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibody (81%) were common laboratory abnormalities. Cardiovascular manifestations included myocardial dysfunction (55%), shock (48%) and coronary artery changes (10%). The treatment included intensive care support (57%), non-invasive (33%) and invasive (18%) ventilation, vasoactive drugs (47%), intravenous immunoglobulin (IVIG) (83%), steroids (85%) and aspirin (87%). The mortality was 5% (n = 6). During the second wave, a significantly higher proportion had positive SARS-CoV-2 antibody, contact with COVID-19 and oral mucosal changes; lower markers of inflammation; lower proportion had lymphopenia, elevated IL-6 and ferritin; lower rates of shock, myocardial dysfunction and coronary artery changes; lesser need of PICU admission, fluid boluses, vasoactive drugs and IVIG; and shorter hospital stay.

CONCLUSION

MIS-C is a febrile multisystemic disease characterized by hyperinflammation, cardiovascular involvement, temporal relationship to SARS-CoV-2 and good outcome with immunomodulation and intensive care. During the second wave, the severity of illness, degree of inflammation, intensive care needs, and requirement of immunomodulation were less as compared to the first wave.

COVID-19 in Children

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus. More than 5 million children have been infected in the United States. Risk factors for more severe disease progression include obesity, pulmonary disease, gastrointestinal disorders, and neurologic comorbidities. Children with COVID-19 are admitted to the pediatric intensive care unit because of severe acute COVID-19 illness or COVID-19-associated multisystem inflammatory syndrome in children. The delta surge of 2021 was responsible for an increased disease burden in children and points to the key role of vaccinating children against this sometimes-deadly disease.

Severe Acute Respiratory Syndrome Coronavirus 2 Infections in Children

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in children generally have milder presentations, but severe disease can occur in all ages. MIS-C and persistent post-acute COVID-19 symptoms can be experienced by children with previous infection and emphasize the need for infection prevention. Optimal treatment for COVID-19 is not known, and clinical trials should include children to guide therapy. Vaccines are the best tool at preventing infection and severe outcomes of COVID-19. Children suffered disproportionately during the pandemic not only from SARS-CoV-2 infection but because of disruptions to daily life, access to primary care, and worsening income inequalities.

Long-Term COVID 19 Sequelae in Adolescents: the Overlap with Orthostatic Intolerance and ME/CFS

Purpose of Review

To discuss emerging understandings of adolescent long COVID or post-COVID-19 conditions, including proposed clinical definitions, common symptoms, epidemiology, overlaps with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and orthostatic intolerance, and preliminary guidance on management.

Recent Findings

The recent World Health Organization clinical case definition of post-COVID-19 condition requires a history of probable or confirmed SARS-CoV-2 infection, with symptoms starting within 3 months of the onset of COVID-19. Symptoms must last for at least 2 months and cannot be explained by an alternative diagnosis. Common symptoms of the post-COVID-19 condition include, but are not limited to, fatigue, shortness of breath, and cognitive dysfunction. These symptoms generally have an impact on everyday functioning. The incidence of prolonged symptoms following SARS-CoV-2 infection has proven challenging to define, but it is now clear that those with relatively mild initial infections, without severe initial respiratory disease or end-organ injury, can still develop chronic impairments, with symptoms that overlap with conditions like ME/CFS (profound fatigue, unrefreshing sleep, post-exertional malaise, cognitive dysfunction, and orthostatic intolerance).

Summary

We do not yet have a clear understanding of the mechanisms by which individuals develop post-COVID-19 conditions. There may be several distinct types of long COVID that require different treatments. At this point, there is no single pharmacologic agent to effectively treat all symptoms. Because some presentations of post-COVID-19 conditions mimic disorders such as ME/CFS, treatment guidelines for this and related conditions can be helpful for managing post-COVID-19 symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40124-022-00261-4.

Longitudinal Outcomes and Monitoring of Patients With Multisystem Inflammatory Syndrome in Children

The acute manifestations and short-term outcomes of multisystem inflammatory syndrome (MIS-C) have been extensively described; however, our understanding of the longitudinal outcomes associated with this condition continue to evolve. Here we review the existing literature on outcomes of MIS-C up to 1 year following diagnosis and summarize current published expert recommendations for management and follow up of these patients.

Six-month multidisciplinary follow-up in multisystem inflammatory syndrome in children: An Italian single-center experience

BACKGROUND

A severe multisystem inflammatory syndrome in children (MIS-C) related to SARS-CoV-2 has been described after infection. A limited number of reports have analyzed the long-term complications related to pro-inflammatory status in MIS-C. We evaluated multiorgan impairment at the 6-month follow-up in MIS-C.

METHODS

We enrolled 33 pediatric patients consecutively hospitalized for MIS-C and monitored for almost 6 months. The inter-relationship of patient's features and disease severity at admission with long term complications was studied by multivariate analysis.

RESULTS

Endo-metabolic derangement, cardiac injury, respiratory, renal and gastrointestinal manifestations and neurological involvement are part of the initial presentation. The most abnormalities appear to resolve within the first few weeks, without significant long term dysfunction at the 6-months follow-up, except for endocrine (non-thyroidal illness syndrome in 12.1%, insulin resistance in 21.2%) and neurological system (27.3% cognitive or psychological, behavioral, adaptive difficulties). Endocrine and heart involvement at admission represent a significant factor on the long term sequelae; however no association between severity score and long-term outcome was noted.

CONCLUSIONS

The severity of initial clinical presentation may be associated to organ domain, however it is not related to long term sequelae. The prevalent organ restoration supports a predominant indirect immune-mediated injury triggered by a systemic inflammatory response; however a direct damage due to the viral entry could be not excluded. Eventhought our preliminary results seem to suggest that MIS-C is not a long-term risk condition for children health, a longer follow-up is mandatory to confirm this hypothesis.

Risk for severe outcomes of COVID-19 and PIMS-TS in children with SARS-CoV-2 infection in Germany

Although children and adolescents have a lower burden of SARS-CoV-2-associated disease compared to adults, assessing the risk for severe outcomes among SARS-CoV-2-infected children remains difficult due to a high rate of undetected cases. We combine data from three data sources - a national seroprevalence study (the SARS-CoV-2 KIDS study), the nationwide, state-based reporting system for PCR-confirmed SARS-CoV-2 infections in Germany, and a nationwide registry on children and adolescents hospitalized with either SARS-CoV-2 or pediatric inflammatory multisystem syndrome (PIMS-TS, also known as MIS-C) - in order to provide estimates on the risk of hospitalization for COVID-19-related treatment, intensive care admission, and death due to COVID-19 and PIMS-TS in children. The rate of hospitalization for COVID-19-related treatment among all SARS-CoV-2 seropositive children was 7.13 per 10,000, ICU admission 2.21 per 10,000, and case fatality was 0.09 per 10,000. In children without comorbidities, the corresponding rates for severe or fatal disease courses were substantially lower. The lowest risk for the need of COVID-19-specific treatment was observed in children aged 5-11 without comorbidities. In this group, the ICU admission rate was 0.37 per 10,000, and case fatality could not be calculated due to the absence of cases. The overall PIMS-TS rate was 2.47 per 10,000 SARS-CoV-2 infections, the majority being children without comorbidities.

CONCLUSION

Overall, the SARS-CoV-2-associated burden of a severe disease course or death in children and adolescents is low. This seems particularly the case for 5-11-year-old children without comorbidities. By contrast, PIMS-TS plays a major role in the overall disease burden among all pediatric age groups.

WHAT IS KNOWN

• SARS-CoV-2-associated burden of disease in children is considered to be low, but accurate risk estimates accounting for clinically undiagnosed infections are lacking. • Asymptomatic SARS-CoV-2 infections are common in children.

WHAT IS NEW

• We provide risk estimates for hospitalization for COVID-19-related treatment, ICU admission, death from COVID-19, and PIMS-TS for children with SARS-CoV-2 infections by pooling different data sources. • The risk for PIMS-TS exceeds the risk for severe COVID-19 in all age groups; the risk for severe COVID-19 is the lowest in 5-11 years old.

Cardiovascular Magnetic Resonance in Children with Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with COVID-19: Institutional Protocol-Based Medium-Term Follow-up Study

Multisystem inflammatory syndrome in children (MIS-C) secondary to COVID-19 infection in previously healthy children often results in subtle but persistent echocardiographic abnormalities despite complete clinical recovery. This study was done to investigate medium-term cardiovascular outcomes of patients with MIS-C using cardiovascular magnetic resonance imaging (CMR). This is a single-center retrospective study of patients aged less than 21 years, diagnosed with MIS-C who received an outpatient CMR, around 6 months after discharge. CMR was done in patients with significant troponin leak or depressed LVEF. CMR performed on a GE Signa HDxt 1.5 Tesla magnet with a myocarditis protocol. Diagnosis of myocarditis was determined by the original Lake Louise Criteria. There were 21 patients with a median age of 11 years, (IQR 8-13 years), who underwent CMR at median follow-up duration of 6 months (IQR 5-7 months). At the peak of illness during admission, there were 95.2% patients with abnormal Troponin I and BNP. By echocardiogram, 76.2% had left ventricular systolic dysfunction and 9.5% had coronary ectasia, which all resolved by 6 months. By CMR, there were five patients (23.8%) with abnormal left atrial volume, one patient (4.8%) with an abnormal indexed left ventricular end-diastolic volume, and three patients (15%) with abnormal LVEF. There was no evidence of myocardial edema in T2-weighted image sequence. There were three patients with persistent late gadolinium enhancement (14.3%). Follow-up CMR is a useful tool in diagnosing subtle myocardial abnormalities and guide necessity for future follow-up.

Global Myocardial Strain in Multisystem Inflammatory Syndrome in Children, Kawasaki Disease, and Healthy Children: A Network Meta-Analysis

BACKGROUND

Nearly 6,000 multisystem inflammatory syndrome in children (MIS-C) have been reported in the United States by November 2021. Left ventricular global myocardial strain has been proved to be one of the best evidence of the diagnostic and prognostic implications for cardiac dysfunction. The global myocardial strain change of MIS-C in the acute phase was still unclear.

METHODS

PubMed and other sources were searched. A network meta-analysis was conducted. MIS-C was divided into two groups according to left ventricular ejection fraction (LVEF): MIS-C with depressed ejection fraction (MIS-C dEF) and MIS-C with preserved ejection fraction (MIS-C pEF). Global longitudinal strain (GLS) and global circumferential strain (GCS) were compared among MIS-C, Kawasaki disease (KD), and healthy children.

RESULTS

In total, nine case-control studies were included, published between 2014 and 2021. These studies involved 107 patients with MIS-C, 188 patients with KD, and 356 healthy children. After Bayesian analysis, MIS-C dEF group was found to have a lower LVEF, higher GLS and GCS than the KD groups. Both MIS-C pEF and KD had similar GLS and GCS, which were higher than healthy controls. There was no difference of LVEF among MIS-C pEF, KD, and healthy controls.

CONCLUSION

MIS-C dEF was more severe than KD, both in LVEF and global myocardial strain. MIS-C pEF and KD were similar with mild impaired left ventricular myocardial strain compared with the healthy children. Global myocardial strain may be a monitoring index for MIS-C.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021264760].

The impact of the COVID-19 pandemic on child health

Most Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infections in children are mild or asymptomatic. Severe Coronavirus Disease 2019 (COVID-19) in children is infrequent. An estimated 0.3–1.3% of children with SARS-CoV-2 infection were admitted to hospital, and of these 13–23% needed critical care. SARS-CoV-2 related deaths were very rare in children, estimated at 2 per million. The vast majority of admitted children had one of shortness of breath, fever, and cough, but atypical symptoms are more common in children. Cases of Multisystem Inflammatory Syndrome in Children (MIS-C) have been linked to SARS-CoV-2 infection. Cardinal symptoms include prolonged fever, clinical signs of inflammation, gastro-intestinal symptoms, and cardiac dysfunction. Twenty two to 80% of patients with MIS-C needed critical care; mortality of MIS-C is around 2%. Six to 24% of children with MIS-C had coronary artery dilatation or cardiac aneurysms. Equipoise still exists between first-line treatment with immunoglobulins and steroids. Outcomes for children with MIS-C are generally very good in those recognised early and started on appropriate treatment. Vaccination schemes for children are rapidly expanding, with the benefits of preventing severe COVID-19 disease and MIS-C and reducing community transmission outweighing the risks of adverse events of, amongst others, myocarditis temporally related to COVID-19 vaccination in children and young adults. The imposed social distancing measures reduced the overall number of children with acute illness or injury presenting to urgent and emergency care facilities worldwide. No clear signal was seen that large numbers of children had a delayed presentation to emergency care departments with a serious illness. The social distancing measures negatively impacted the mental health of children.