Multisystem Inflammatory Syndrome in U.S. Children and Adolescents

Clinical phenotypes and outcomes in children with multisystem inflammatory syndrome across SARS-CoV-2 variant eras: a multinational study from the 4CE consortium

Background

Multisystem inflammatory syndrome in children (MIS-C) is a severe complication of SARS-CoV-2 infection. It remains unclear how MIS-C phenotypes vary across SARS-CoV-2 variants. We aimed to investigate clinical characteristics and outcomes of MIS-C across SARS-CoV-2 eras.

Methods

We performed a multicentre observational retrospective study including seven paediatric hospitals in four countries (France, Spain, U.K., and U.S.). All consecutive confirmed patients with MIS-C hospitalised between February 1st, 2020, and May 31st, 2022, were included. Electronic Health Records (EHR) data were used to calculate pooled risk differences (RD) and effect sizes (ES) at site level, using Alpha as reference. Meta-analysis was used to pool data across sites.

Findings

Of 598 patients with MIS-C (61% male, 39% female; mean age 9.7 years [SD 4.5]), 383 (64%) were admitted in the Alpha era, 111 (19%) in the Delta era, and 104 (17%) in the Omicron era. Compared with patients admitted in the Alpha era, those admitted in the Delta era were younger (ES -1.18 years [95% CI -2.05, -0.32]), had fewer respiratory symptoms (RD -0.15 [95% CI -0.33, -0.04]), less frequent non-cardiogenic shock or systemic inflammatory response syndrome (SIRS) (RD -0.35 [95% CI -0.64, -0.07]), lower lymphocyte count (ES -0.16 × 109/uL [95% CI -0.30, -0.01]), lower C-reactive protein (ES -28.5 mg/L [95% CI -46.3, -10.7]), and lower troponin (ES -0.14 ng/mL [95% CI -0.26, -0.03]). Patients admitted in the Omicron versus Alpha eras were younger (ES -1.6 years [95% CI -2.5, -0.8]), had less frequent SIRS (RD -0.18 [95% CI -0.30, -0.05]), lower lymphocyte count (ES -0.39 × 109/uL [95% CI -0.52, -0.25]), lower troponin (ES -0.16 ng/mL [95% CI -0.30, -0.01]) and less frequently received anticoagulation therapy (RD -0.19 [95% CI -0.37, -0.04]). Length of hospitalization was shorter in the Delta versus Alpha eras (-1.3 days [95% CI -2.3, -0.4]).

Interpretation

Our study suggested that MIS-C clinical phenotypes varied across SARS-CoV-2 eras, with patients in Delta and Omicron eras being younger and less sick. EHR data can be effectively leveraged to identify rare complications of pandemic diseases and their variation over time.

Funding

None.

Kidney complications associated with COVID-19 infection and vaccination in children and adolescents: a brief review

Coronavirus disease 2019 (COVID-19) has spread considerably across the globe, affecting numerous children and adolescents besides adults. Despite its relatively lower incidence rates in children and adolescents than in adults, some infected children and adolescents exhibit a severe postinflammatory response known as multisystem inflammatory syndrome in children, followed by acute kidney injury, a common complication. Meanwhile, few reports have been available regarding kidney complications such as idiopathic nephrotic syndrome and other glomerulopathies associated with COVID-19 infection and vaccination in children and adolescents. However, the morbidity and mortality of these complications are not exceptionally high; more importantly, causality has yet to be clearly established. Finally, vaccine hesitancy in these age groups should be addressed, considering the strong evidence of COVID-19 vaccine safety and efficacy.

COVID-19

COVID-19, the illness caused by SARS-CoV-2, became a worldwide pandemic in 2020. Initial clinical manifestations range from asymptomatic infection to mild upper respiratory illness but may progress to pulmonary involvement with hypoxemia and, in some cases, multiorgan involvement, shock, and death. Older adults, pregnant persons, those with common comorbidities, and those with immunosuppression are at greatest risk for progression. Vaccination is effective in preventing symptomatic infection and reducing risk for severe disease, hospitalization, and death. Antiviral treatment and immunomodulators have been shown to benefit certain patients. This article summarizes current recommendations on prevention, diagnosis, management, and treatment of COVID-19.

Innate immune dysregulation in multisystem inflammatory syndrome in children (MIS-C)

MIS-C is a systemic inflammation disorder with poorly characterised immunopathological mechanisms. We compared changes in the systemic immune response in children with MIS-C (n = 12, 5-13 years) to healthy controls (n = 14, 5-15 years). Analysis was done in whole blood treated with LPS. Expression of CD11b and Toll-like receptor-4 (TLR4) in neutrophils and monocytes were analysed by flow cytometry. Serum cytokines (IL-1β, IL-2, IL-6, IL-8, IL-10, IL-Ira, TNF-α, TNF-β, IFN-Υ, VEGF, EPO and GM-CSF) and mRNA levels of inflammasome molecules (NLRP3, ASC and IL-1β) were evaluated. Subpopulations of lymphocytes (CD3+, CD19+, CD56+, CD4+, CD8+, TCR Vδ1+, TCR Vδ2+) were assessed at basal levels. Absolute counts of neutrophils and NLR were high in children with MIS-C while absolute counts of lymphocytes were low. Children with MIS-C had increased levels of IL-6, IL-10, TNF-β and VEGF serum cytokines at the basal level, and significantly increased TNF-β post-LPS, compared to controls. IL-1RA and EPO decreased at baseline and post-LPS in MIS-C patients compared to controls. The percentage of CD3+ cells, NK cells and Vδ1 was lower while B cells were higher in children with MIS-C than in controls. Dysregulated immune response in children with MIS-C was evident and may be amenable to immunomodulation.

Diagnosis, Progress, and Treatment Update of Kawasaki Disease

Kawasaki disease (KD) is an acute inflammatory disorder that primarily affects children and can lead to coronary artery lesions (CAL) if not diagnosed and treated promptly. The original clinical criteria for diagnosing KD were reported by Dr. Tomisaku Kawasaki in 1967 and have been used for decades. However, research since then has highlighted the limitations of relying solely on these criteria, as they might lead to underdiagnosis or delayed diagnosis, potentially increasing the risk of coronary artery complications. This review appears to discuss several important aspects related to KD diagnosis and management. The current diagnostic methods for KD might need updates, especially considering cases that do not fit the typical clinical criteria. Recognizing diagnostic pitfalls and distinguishing KD from other conditions that might have similar clinical presentations is essential. The differences and similarities between KD and Multisystem Inflammatory Syndrome in Children (MIS-C), another inflammatory condition that has been associated with COVID-19, were also reviewed. The review explores the potential role of eosinophil count, new biomarkers, microRNA panels, and scoring systems in aiding the diagnosis of KD. Overall, the review article provides a comprehensive overview of the evolving landscape of KD diagnosis and management, incorporating new diagnostic methods, biomarkers, and treatment approaches to improve patient outcomes and reduce the risk of complications.

Similarities and Differences between Multisystem Inflammatory Syndrome in Children (MIS-C) and Kawasaki Disease Shock Syndrome

This study aimed to investigate the characteristics of COVID-19-associated multisystem inflammatory syndrome in children (MIS-C) and Kawasaki disease shock syndrome (KDSS) and to compare the similarities and differences between the two diseases. The incidence of KDSS and MIS-C was also estimated. Medical records of patients diagnosed with MIS-C or KDSS at four hospitals from January 2013 to December 2022 were retrospectively reviewed. Thirty-one patients were enrolled in the study in either an MIS-C group (n = 22) or a KDSS group (n = 9). The incidence of KDSS in KD was 0.8% (9/1095) and the incidence of MIS-C versus KD was 10.2% (22/216). Compared with the MIS-C group, the KDSS group had longer hospital stays and more severe systemic inflammation (e.g., anemia, elevated C-reactive protein, hypoalbuminemia, and pyuria) and organ dysfunction (e.g., number of involved organs, shock, vasoactive infusion, and intensive care unit admission). All patients in the MIS-C group, but none in the KDSS group, including two patients during the COVID-19 pandemic, had laboratory evidence of SARS-CoV-2 infection. MIS-C and KDSS shared demographic, clinical, and laboratory characteristics; organ dysfunction; treatment; and outcomes. Overall severity was more severe in patients with KDSS than in those with MIS-C. The most important difference between MIS-C and KDSS was whether SARS-CoV-2 was identified as an infectious trigger.

The prevalence and outcomes of hyponatremia in children with COVID-19 and multisystem inflammatory syndrome in children (MIS-C)

Introduction

To assess the prevalence of hyponatremia among pediatric patients with coronavirus disease 2019 (COVID-19) and Multisystem Inflammatory Syndrome in Children (MIS-C) and determine if pediatric hyponatremia was associated with an increased length of stay, higher rates of mechanical ventilation, and/or elevated inflammatory markers on admission as compared to eunatremic patients.

Methods

Electronic health records were retrospectively analyzed for 168 children less than 18 years old with COVID-19 or MIS-C who were admitted to pediatric units within the Northwell Health system. The primary exposure was hyponatremic status (serum sodium <135 mEq/L) and the primary outcomes were length of stay, mechanical ventilation usage and increased inflammatory markers.

Results

Of the 168 children in the study cohort, 95 (56%) were admitted for COVID-19 and 73 (43.5%) for MIS-C. Overall, 60 (35.7%) patients presented with hyponatremia on admission. Patients with hyponatremia had higher rates of intensive care unit admission when compared to eunatremic patients (32/60 [53.3%] vs. 39/108 [36.1%], p = 0.030). In regression models, hyponatremia was not significantly associated with increased length of stay or mechanical ventilation rates. After adjustment for relevant confounders, hyponatremia remained associated with an increased square root CRP (β = 1.79: 95% CI: 0.22-3.36) and lower albumin levels (β = -0.22: 95% CI: -0.42--0.01).

Conclusion

Hyponatremia is common in pediatric COVID-19 and MIS-C. Hyponatremia was associated with a lower albumin and higher square root CRP levels. This may suggest an association of inflammation with lower serum sodium levels.

Anticoagulant therapy in COVID-19: A narrative review

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest itself in several ways, including coagulopathy and thrombosis. These complications can be the first and sometimes only manifestations of SARS-CoV-2 infection and can occur early or late in the course of the disease. However, these symptoms are more prevalent in hospitalized patients with venous thromboembolism, particularly those admitted to intensive care units. Moreover, various forms of arterial and venous thrombosis, or micro- or macro-vasculature embolisms, have been reported during the current pandemic. They have led to harmful consequences, such as neurological and cardiac events, nearly all resulting from the hypercoagulable state caused by this viral infection. The severe hypercoagulability observed in patients with COVID-19 accounts for most cases of the disease that become critical. Therefore, anticoagulants seem to be one of the most vital therapeutics for treating this potentially life-threatening condition. In the current paper, we present a thorough review of the pathophysiology of COVID-19-induced hypercoagulable state and the use of anticoagulants to treat SARS-CoV-2 infections in different patient groups, as well as their pros and cons.

Efficacy of Biomarkers in Identifying Abnormal Echocardiogram in Multisystem Inflammatory Syndrome in Children

Cardiac involvement in multisystem inflammatory syndrome in children (MIS-C) is common and contributes to significant morbidity and mortality. We evaluated the efficacy of cardiac biomarkers in detection of an abnormal echocardiogram in MIS-C patients. A retrospective chart review of children ≤18 years diagnosed with MIS-C at our hospital was performed. Sensitivity and specificity of high-sensitivity troponin I (hs-TnI) and B-type natriuretic peptide (BNP) were estimated for an abnormal echocardiogram. Of the 83 patients with MIS-C, 33 (39.8%) had an abnormal echocardiogram. While BNP was more sensitive, hs-TnI >50 ng/L was more specific for detecting an abnormal echocardiogram. Compared with children who had normal hs-TnI levels (<17 ng/L), those with hs-TnI >50 ng/L were more likely to have an echocardiographic abnormality (relative risk: 4.9; 95% CI, 2.9-10.9). Children with abnormal BNP and/or troponin (especially greater than 3-fold the upper limit of normal) would benefit from an urgent echocardiogram in the emergency department.

Transient anti-cytokine autoantibodies superimpose the hyperinflammatory response in Kawasaki disease and multisystem inflammatory syndrome in children: a comparative cohort study on correlates of disease

BACKGROUND

Children with SARS-CoV-2 related Multisystem Inflammatory Syndrome in Children (MIS-C) often present with clinical features that resemble Kawasaki disease (KD). Disease severity in adult COVID-19 is associated to the presence of anti-cytokine autoantibodies (ACAAs) against type I interferons. Similarly, ACAAs may be implicated in KD and MIS-C. Therefore, we explored the immunological response, presence of ACAAs and disease correlates in both disorders.

METHODS

Eighteen inflammatory plasma protein levels and seven ACAAs were measured in KD (n = 216) and MIS-C (n = 56) longitudinally by Luminex and/or ELISA. Levels (up to 1 year post-onset) of these proteins were related to clinical data and compared with healthy paediatric controls.

FINDINGS

ACAAs were found in both patient groups. The presence of ACAAs lagged behind the inflammatory plasma proteins and peaked in the subacute phase. ACAAs were mostly directed against IFN-γ (>80%) and were partially neutralising at best. KD presented with a higher variety of ACAAs than MIS-C. Increased levels of anti-IL-17A (P = 0·02) and anti-IL-22 (P = 0·01) were inversely associated with ICU admission in MIS-C. Except for CXCL10 in MIS-C (P = 0·002), inflammatory plasma proteins were elevated in both KD and MIS-C. Endothelial angiopoietin-2 levels were associated with coronary artery aneurysms in KD (P = 0·02); and sCD25 (P = 0·009), angiopoietin-2 (P = 0·001), soluble IL-33-receptor (ST2, P = 0·01) and CXCL10 (P = 0·02) with ICU admission in MIS-C.

INTERPRETATION

Markers of endothelial activation (E-selectin, angiopoietin-2), and innate and adaptive immune responses (macrophages [CD163, G-CSF], neutrophils [lipocalin-2], and T cells [IFN-γ, CXCL10, IL-6, IL-17]), are upregulated in KD and MIS-C. ACAAs were detected in both diseases and, although only partly neutralising, their transient presence and increased levels in non-ICU patients may suggest a dampening role on inflammation.

FUNDING

The Kawasaki study is funded by the Dutch foundation Fonds Kind & Handicap and an anonymous donor. The sponsors had no role in the study design, analysis, or decision for publication.

Pediatric endocrinopathies related to COVID-19: an update

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the seventh coronavirus to be linked to human disease. The SARS-CoV-2 virus may have several pathophysiologic interactions with endocrine systems, resulting in disruptions in glucose metabolism, hypothalamus and pituitary function, adrenal function, and mineral metabolism. An increasing amount of evidence demonstrates both the influence of underlying endocrine abnormalities on the outcome of COVID-19 and the effect of the SARS-CoV-2 virus on endocrine systems. However, a systematic examination of the link to pediatric endocrine diseases has been missing.

DATA SOURCES

The purpose of this review is to discuss the impact of SARS-CoV-2 infection on endocrine systems and to summarize the available knowledge on COVID-19 consequences in children with underlying endocrine abnormalities. For this purpose, a literature search was conducted in EMBASE, and data that were discussed about the effects of COVID-19 on endocrine systems were used in the current study.

RESULTS

Treatment suggestions were provided for endocrinopathies associated with SARS-CoV-2 infection.

CONCLUSIONS

With the global outbreak of COVID-19, it is critical for pediatric endocrinologists to understand how SARS-CoV-2 interacts with the endocrine system and the therapeutic concerns for children with underlying problems who develop COVID-19. While children and adults share certain risk factors for SARS-CoV-2 infection sequelae, it is becoming obvious that pediatric responses are different and that adult study results cannot be generalized. While pediatric research gives some insight, it also shows the need for more study in this area.

Cardiac complications in children with acute COVID-19 vs multisystem inflammatory syndrome in children (MIS-C)

BACKGROUND

Cardiac involvement can lead to significant morbidity in children with acute COVID-19 or multisystem inflammatory syndrome in children (MIS-C). However, the presentation and outcomes of cardiac involvement may differ among these 2 conditions. We aimed to compare the frequency and extent of cardiac involvement among children admitted with acute COVID-19 vs those with MIS-C.

METHODS

We conducted a cross sectional study of patients admitted to our hospital from March 2020 to August 2021 with symptomatic acute COVID-19 or MIS-C. Cardiac involvement was defined by presence of 1 or more of the following: elevated troponin, elevated brain natriuretic peptide, reduced left ventricular ejection fraction on echocardiogram, coronary dilation on echocardiogram, or abnormal electrocardiogram reading.

RESULTS

Among 346 acute COVID-19 patients with median age of 8.9 years and 304 MIS-C patients with median age of 9.1 years, cardiac involvement was present in 33 acute COVID-19 patients (9.5%) and 253 MIS-C patients (83.2%). The most common cardiac abnormality was abnormal electrocardiogram in acute COVID-19 patients (7.5%) and elevated troponin in MIS-C patients (67.8%). Among acute COVID-19 patients, obesity was significantly associated with cardiac involvement. Among MIS-C patients, non-Hispanic Black race/ethnicity was significantly associated with cardiac involvement.

CONCLUSIONS

Cardiac involvement is much more common in children with MIS-C than in those with acute COVID-19. These results reinforce our standardized practice of performing full cardiac evaluations and follow-up in all patients with MIS-C but only in acute COVID-19 patients with signs or symptoms of cardiac involvement.

Thrombotic complications in children with Coronavirus disease 2019 and Multisystem Inflammatory Syndrome of Childhood

Coronavirus disease 2019 (COVID-19) associated coagulopathy is multifactorial and involves inflammation driven hypercoagulability, endothelial dysfunction, platelet activation, and impaired fibrinolysis. Hospitalized adults with COVID-19 are at an increased risk of both venous thromboembolism and ischemic stroke, resulting in adverse outcomes, including increased mortality. Although COVID-19 in children follows a less severe course, both arterial and venous thromboses have been reported in hospitalized children with COVID-19. Additionally, some children develop a postinfectious, hyperinflammatory illness termed multisystem inflammatory syndrome of childhood (MIS-C), which is also associated with hypercoagulability and thrombosis. Several randomized trials have evaluated the safety and efficacy of antithrombotic therapy in adults with COVID-19, although similar pediatric data are lacking. In this narrative review, we discuss the postulated pathophysiology of COVID-19 coagulopathy and summarize principal findings of the recently completed adult trials of antithrombotic therapy. We provide an up-to-date summary of pediatric studies investigating the rate of venous thromboembolism and ischemic stroke in COVID-19 and multisystem inflammatory syndrome of childhood in addition to reviewing the findings of the single, nonrandomized pediatric trial investigating the safety of prophylactic anticoagulation. Lastly, we outline adult and pediatric consensus guidelines on the use of antithrombotic therapy in this cohort. A detailed discussion of the practical implementation and current limitations of published data will hopefully address the knowledge deficits surrounding the use of antithrombotic therapy in children with COVID-19 and generate hypotheses for future research.

Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Postacute Sequelae of SARS-CoV-2: More in Common Than Not?

TOPIC IMPORTANCE

Postacute sequelae of SARS-CoV-2 (PASC) is a long-term consequence of acute infection from COVID-19. Clinical overlap between PASC and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has been observed, with shared symptoms including intractable fatigue, postexertional malaise, and orthostatic intolerance. The mechanistic underpinnings of such symptoms are poorly understood.

REVIEW FINDINGS

Early studies suggest deconditioning as the primary explanation for exertional intolerance in PASC. Cardiopulmonary exercise testing reveals perturbations related to systemic blood flow and ventilatory control associated with acute exercise intolerance in PASC, which are not typical of simple detraining. Hemodynamic and gas exchange derangements in PASC have substantial overlap with those observed with ME/CFS, suggestive of shared mechanisms.

SUMMARY

This review illustrates exercise pathophysiologic commonalities between PASC and ME/CFS that will help guide future diagnostics and treatment.

A global systematic review and meta-analysis on the emerging evidence on risk factors, clinical characteristics, and prognosis of multisystem inflammatory syndrome in adults (MIS-A)

Background

The multisystem inflammatory syndrome in adults (MIS-A) has emerged, similar to those in children associated with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) [multisystem inflammatory syndrome in children (MIS-C)]. This review aimed to analyze the risk factors, clinical course, and prognosis of MIS-A.

Methods

A comprehensive literature search was conducted using several databases for cases reporting MIS-A from 1 December 2019 till 9 September 2021. The case definitions used to identify potential cases were those recommended by the World Health Organization, Center for Disease Control, and individual country/physician classification. The meta-analysis was performed using Comprehensive Meta-Analysis (CMA) 2.2.027 and Review Manager (RevMan) 5.4.1, employing 95% confidence intervals (CI).

Results

Seventy studies were assessed for full-text eligibility, out of which 37 were included. The mean age of the study population was 32.52±10.29 years. The most common symptoms were fever (89.8%, 95% CI: 77.7-95.7%) and diarrhea (49%, 95% CI: 35.4-62.7%). Ventricular tachycardia (57.1%, 95% CI: 43.1-70.1%) was the most common electro-cardiac abnormality. The most common inflammatory marker was elevated C-reactive protein (89.8%, 95% CI: 77.7-95.7%). Abnormal echocardiogram was the most common imaging test result (commonly, ventricular dysfunction and arrhythmias), while steroids were the most administered treatment. Severe cases had a higher need for vasopressor and inotropic support and antibiotic therapy compared to the non-severe cases. One death was reported due to cardiovascular failure.

Conclusion

Our collated findings will help clinicians identify the typical presenting symptoms and optimal management of MIS-A. Further research is required to understand the long-term prognosis and the correlation between coronavirus disease 2019 (COVID-19) and MIS-A to understand its pathogenesis and clinical spectrum.

Echocardiographic Findings in Children with Multisystem Inflammatory Syndrome from Initial Presentation to the First Years after Discharge

OBJECTIVE

We aimed to evaluate clinical and echocardiographic features of the children diag- nosed with multisystem inflammatory syndrome related to severe acute respiratory syndrome coronavirus-2 infection and determine early and mid-term cardiovascular outcomes.

MATERIALS AND METHODS

We retrospectively evaluated 38 children who were diagnosed with multisystem inflammatory syndrome in our hospital between November 2020 and November 2021. Cardiovascular evaluations were performed during hospitalization, at the first, the second, and the third months after discharge, and then cardiac evaluation was repeated at 3-month intervals until a median of 24 weeks (range: 9-56 weeks).

RESULTS

The mean age of patients was 9.6 years and 25 patients had cardiovascular involve- ment. Echocardiography showed that there was left ventricular dysfunction in 11 cases and any coronary abnormalities in 11 cases on admission. Cardiovascular involvement was most fre- quently seen in patients older than 10 years and of male sex. Severe clinical courses occurred in half of them. The mortality rate was 2.6% during hospitalization. At discharge, complete recovery was achieved in 30 cases and partial recovery was seen in 6 cases; there were 1 case with ventricular dysfunction and 5 cases with coronary abnormalities. At the last polyclinic visit, there was no case with symptoms or myocardial dysfunction, there was only 1 case with persist- ing coronary aneurysms.

CONCLUSION

Cardiovascular abnormalities in patients with multisystem inflammatory syndrome show rapid resolution within the first month. We recommend long-term follow-up evaluation for coronary arteries.

Immune responses to SARS-CoV-2 infection and vaccination in children

During the three years since SARS-CoV-2 infections were first described a wealth of information has been gathered about viral variants and their changing properties, the disease presentations they elicit and how the many vaccines developed in record time protect from COVID-19 severe disease in different populations. A general theme throughout the pandemic has been the observation that children and young people in general fare well, with mild symptoms during acute infection and full recovery thereafter. It has also become clear that this is not universally true, as some children develop severe COVID-19 hypoxic pneumonia and even succumb to the infection, while another group of children develop a rare but serious multisystem inflammatory syndrome (MIS-C) and some other children experience prolonged illness following acute infection, post-COVID. Here I will discuss some of the findings made to explain these diverse disease manifestations in children and young people infected by SARS-CoV-2. I will also discuss the vaccines developed at record speed and their efficacy in protecting children from disease.

Unmasking the enigma: An in-depth analysis of COVID-19 impact on the pediatric population

OBJECTIVES

COVID-19, caused by the novel coronavirus, has had a profound and wide-reaching impact on individuals of all age groups across the globe, including children. This review article aims to provide a comprehensive analysis of COVID-19 in children, covering essential topics such as epidemiology, transmission, pathogenesis, clinical features, risk factors, diagnosis, treatment, vaccination, and others. By delving into the current understanding of the disease and addressing the challenges that lie ahead, this article seeks to shed light on the unique considerations surrounding COVID-19 in children and contribute to a deeper comprehension of this global health crisis affecting our youngest population.

METHODS

A comprehensive literature search was conducted to gather the most recent and relevant information regarding COVID-19 in children. Multiple renowned databases, including MEDLINE, PubMed, Scopus, as well as authoritative sources such as the World Health Organization (WHO), the U.S. Food and Drug Administration (FDA), the European Medicines Agency (EMA), and the National Institutes of Health (NIH) websites and others were thoroughly searched. The search included articles, guidelines, reports, clinical trials results and expert opinions published within the past three years, ensuring the inclusion of the latest research findings on COVID-19 in children. Several relevant keywords, including "COVID-19," "SARS-CoV-2," "children," "pediatrics," and related terms were used to maximize the scope of the search and retrieve a comprehensive set of articles.

RESULTS AND CONCLUSION

Three years since the onset of the COVID-19 pandemic, our understanding of its impact on children has evolved, but many questions remain unanswered. While SAR-CoV-2 generally leads to mild illness in children, the occurrence of severe cases and the potential for long-term effects cannot be overlooked. Efforts to comprehensively study COVID-19 in children must continue to improve preventive strategies, identify high-risk populations, and ensure optimal management. By unraveling the enigma surrounding COVID-19 in children, we can strive towards safeguarding their health and well-being in the face of future global health challenges.

Early Treatment of Multisystem Inflammatory Syndrome in Children

BACKGROUND AND OBJECTIVES

Multisystem inflammatory syndrome in children (MIS-C) is a severe hyperinflammatory illness occurring after severe acute respiratory syndrome coronavirus 2 infection. The optimal treatment of MIS-C is unknown, although prior studies have indicated benefits of intravenous immunoglobulin (IVIG) and glucocorticoids. We hypothesize that early treatment with glucocorticoids is associated with shorter hospital length of stay (LOS).

METHODS

This study is a multicenter retrospective cohort study of patients hospitalized with MIS-C over a roughly 1-year period. The primary outcome was hospital LOS comparing subjects who received glucocorticoids within 48 hours of arrival to the treating hospital to those who did not. Secondary outcomes included ICU LOS. Unadjusted and adjusted analyses were performed.

RESULTS

The final analysis included 131 subjects. Subjects who received early glucocorticoids were more likely to receive early IVIG and to require ICU admission. Early glucocorticoid administration was associated with shorter ICU LOS (4 vs 9 days, P = .004) in the unadjusted analysis. In the adjusted analysis, early glucocorticoid administration and early IVIG administration were both independently associated with shorter hospital LOS (incidence rate ratio 0.75, P = .025; incidence rate ratio 0.56, P = .026, respectively).

CONCLUSIONS

Glucocorticoids and intravenous immunoglobulin were independently associated with shorter hospital length of stay when given early in hospitalization to MIS-C patients after accounting for potential confounding factors. The optimal dose and duration of treatment require further investigation, but this study supports early combination therapy with both IVIG and glucocorticoids for all children hospitalized with MIS-C.

Adult-onset Still's disease and fever of unknown origin in India

Despite an essential differential diagnosis for fever of unknown origin (FUO) in young adults, adult-onset Still's disease (AOSD) is infrequently considered and remained underdiagnosed in low-middle-income countries. The present study analyzed the clinical, serological, radiological, and pathological characteristics of AOSD presented as FUO in India. A hospital-based retrospective study of patients aged > 13 years admitted with FUO and later diagnosed with AOSD in Postgraduate Institute of Medical Education and Research, Chandigarh (India), was conducted between January 2014 and December 2020. Petersdorf and Beeson's criteria were used to define FUO. The diagnosis of AOSD was made based on Yamaguchi's criteria. Twenty-seven patients (median age 26 years, 14 females) were enrolled. All presented with intermittent fever with a median duration of 10 weeks. The typical features of AOSD at admission were arthralgia (n = 24), hepatosplenomegaly (n = 21), spiking fever ≥ 39 °C (n = 19), lymphadenopathy (n = 18), typical rash (n = 17), and sore throat (n = 11). Leukocytosis (n = 25) and neutrophilia (n = 19) were frequent. Hyperferritinemia was universal (range, 700-145,003 ng/ml; ≥ 2000, n = 23). At admission, AOSD was suspected in only nine FUO cases, while tuberculosis (n = 16), undifferentiated connective tissue disorder (n = 14), and lymphoproliferative disorder (n = 11) were common diagnostic possibilities. Crispin et al. clinical scale detected AOSD in only 15 (55.5%) FUO patients. Whole-body imaging (n = 27), including fluorodeoxyglucose positron emission tomography (n = 12), demonstrated reticuloendothelial organ-system involvement and serositis. Seventeen (63%) patients had macrophage activation syndrome at the time of AOSD diagnosis. AOSD FUO presents with typical but nonspecific features; thus, early differentiation from common causes (e.g., tuberculosis, lymphoma) is difficult. Macrophage activation syndrome is common in AOSD with FUO presentation.

COVID-19 Disease Characterization and Outcomes Comparison in Pediatrics

Background

It has been reported that children experience less severe COVID-19 symptoms than adults; however, the literature that supports this idea is evolving. The purpose of this study was to retrospectively characterize hospitalized COVID-19-positive pediatric patients with a focus on the assessment of risk factors for poorer outcomes, mortality, and evaluation of interventions utilized and associated clinical outcomes.

Methods

We conducted a multi-center retrospective chart review of patients 18 years old or younger who were COVID-19 positive and admitted to any US HCA Healthcare Pediatric service line between January 1, 2020, and November 30, 2020. We identified 6081 children across 4 states and included them in our data analysis. Negative Binomial Regression was used to measure the associations between characteristics abstracted from medical records and length of hospital stay.

Results

Of the total cohort, 2.7% had at least one comorbidity. The majority of patients were discharged shortly after admission with 93.6% of patients spending less than 48 hours as an inpatient. The mortality rate during the study period was 0.1%. Factors found to be significantly associated with an increased length of stay were time in the intensive care unit (ICU), surgeries, developmental disorders, diabetes, post-traumatic stress disorder (PTSD), suicidal ideation, and type of admission.

Conclusion

The results of this cohort show there was a low disease burden at baseline and during hospitalization in pediatric patients positive for COVID-19. However, as the pandemic continues, future studies that further describe COVID-19 in children will be crucial to fully understand the disease course.

Dilemmas and options for COVID-19 vaccination in children

Over 16 million children have been detected positive for the coronavirus disease 2019 (COVID-19) in the United States since the outbreak of the pandemic. In general, children infected with severe acute respiratory syndrome coronavirus type 2 tend to have lighter symptoms than adults. However, in some cases, the infection can develop into severe forms, such as multisystem inflammatory syndrome in children. Moreover, long-term public health preventive interventions have had some negative effects on the physical and mental health of children. Given the important role that vaccination plays in reducing severe illness and mortality, it is essential for the efficient implementation of vaccination in the pediatric population. Nevertheless, parental distrust of vaccination, especially with regard to its safety and efficacy, hinders this process. Herein, we comprehensively summarize the available data on the safety and effectiveness of COVID-19 vaccine in children. The results show that the currently approved COVID-19 vaccine is safe and effective for children. Although two doses of vaccine in children seem insufficient to prevent Omicron infection, the booster dose provides enhanced protection against infection and severe illness. Most importantly, the bivalent vaccine has been approved for use in the pediatric population to extend the immune response to currently circulating Omicron variant. And the immune protection afforded to newborns after maternal vaccination appears to last only 6 months. Therefore, in the current situation where the rate of virus mutation is accelerating and the COVID-19 pandemic is still severe, it is crucial to extend vaccine protection to children over 6 months of age to weave a tighter safety net.

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.

Analysis of Plasmablasts From Children With Kawasaki Disease Reveals Evidence of a Convergent Antibody Response to a Specific Protein Epitope

BACKGROUND

Kawasaki disease (KD) is a febrile illness of young childhood that can result in coronary artery aneurysms and death. Coronavirus disease 2019 (COVID-19) mitigation strategies resulted in a marked decrease in KD cases worldwide, supporting a transmissible respiratory agent as the cause. We previously reported a peptide epitope recognized by monoclonal antibodies (MAbs) derived from clonally expanded peripheral blood plasmablasts from 3 of 11 KD children, suggesting a common disease trigger in a subset of patients with KD.

METHODS

We performed amino acid substitution scans to develop modified peptides with improved recognition by KD MAbs. We prepared additional MAbs from KD peripheral blood plasmablasts and assessed MAb characteristics that were associated with binding to the modified peptides.

RESULTS

We report a modified peptide epitope that is recognized by 20 MAbs from 11 of 12 KD patients. These MAbs predominantly use heavy chain VH3-74; two-thirds of VH3-74 plasmablasts from these patients recognize the epitope. The MAbs were nonidentical between patients but share a common complementarity-determining region 3 (CDR3) motif.

CONCLUSIONS

These results demonstrate a convergent VH3-74 plasmablast response to a specific protein antigen in children with KD, supporting one predominant causative agent in the etiopathogenesis of the illness.

Short- and mid-term outcomes of multisystem inflammatory syndrome in children: a longitudinal prospective single-center cohort study

Background

Multisystem inflammatory syndrome in children (MIS-c) emerged during the coronavirus disease 2019 pandemic and is associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite the extensively studied clinical manifestation of acute condition, the short- and long-term effects of MIS-c on children's health are unknown.

Methods

This was a prospective longitudinal cohort study. Children aged <18 years who met the Centers for Disease Prevention and Control (CDC) diagnostic criteria and who were admitted to the Children's Clinical University Hospital of Latvia (CCUH) between July 1, 2020, and April 15, 2022, were enrolled in the study. An outpatient follow-up program was initiated in July 2020. All children were evaluated at 2 weeks, 2 months (1-3 months), and 6 months (5-7 months) after discharge. The face-to-face interviews comprised four domains as follows: symptom assessment, physical examination, laboratory testing, and cardiological investigation [including electrocardiogram (ECG) and echocardiography (echo)].

Results

Overall, 21 patients with MIS-c were enrolled. The median age of the study group was 6 years. At the 2-week follow-up, almost half of the patients (N = 10, 47.6%) reported exercise intolerance with provoked tiredness. Laboratory tests showed a considerable increase in blood cell count, with a near doubling of leukocyte and neutrophil counts and a tripling of thrombocyte levels. However, a decline in the levels of inflammatory and organ-specific markers was observed. Cardiological investigation showed significant improvement with gradual resolution of the acute-phase pathological findings. Within 2 months, improvement in exercise capacity was observed with 5-fold and 2-fold reductions in physical intolerance (N = 2, 9.5%) and physical activity-induced fatigue (N = 5, 23.8%), respectively. Normalization of all blood cell lines was observed, and cardiological investigation showed no persistent changes. At the 6-month visit, further improvement in the children's exercise capacity was observed, and both laboratory and cardiological investigation showed no pathological changes.

Conclusions

Most persistent symptoms were reported within the first 2 weeks after the acute phase, with decreased physical activity tolerance and activity-induced fatigue as the main features. A positive trend was observed at each follow-up visit as the spectrum of the children's complaints decreased. Furthermore, rapid normalization of laboratory markers and cardiac abnormalities was observed.

Prognostic role of euthyroid sick syndrome in MIS-C: results from a single-center observational study

Background

Euthyroid sick syndrome (ESS) is characterized by low serum levels of free triiodothyronine (fT3) with normal or low levels of thyroid stimulating hormone (TSH) and free thyroxine (fT4) and is reported in different acute clinical situations, such as sepsis, diabetic ketoacidosis and after cardiac surgery. Our aim was to evaluate the predicting role of ESS for disease severity in patients with Multisystem Inflammatory Syndrome in children (MIS-C).

Methods

A single-centre observational study on consecutive patients with MIS-C. Before treatment clinical, and laboratory data were collected and, in a subset of patients, thyroid function tests were repeated 4 weeks later. Variables distribution was analyzed by Mann-Whitney U-test and correlations between different parameters were calculated by Spearman's Rho coefficient.

Results

Forty-two patients were included and 36 (85.7%) presented ESS. fT3 values were significantly lower in patients requiring intensive care, a strong direct correlation was shown between fT3 and Hb, platelet count and ejection fraction values. A significant inverse correlation was retrieved between fT3 levels and C-reactive protein, brain natriuretic peptide, IL-2 soluble receptor and S-100 protein. Subjects with severe myocardial depression (EF < 45%) had lower fT3 values than subjects with higher EF. The thyroid function tests spontaneously normalized in all subjects who repeated measurement 4 weeks after admission.

Conclusion

ESS is a frequent and transient condition in acute phase of MIS-C. A severe reduction of fT3 must be considered as important prognostic factor for severe disease course, with subsequent relevant clinical impact in the management of these patients.

Determination of Risk Factors for Severe Life-Threatening Course of Multisystem Inflammatory Syndrome Associated with COVID-19 in Children

Multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C) is a life-threatening condition that often requires intensive care unit (ICU) admission. The aim of this study was to determine risk factors for severe/life-threatening course of MIS-C. The study included 166 patients (99 boys, 67 girls) aged 4 months-17 years (median 8.2 years). The criterion of severity was the fact of ICU admission. To conduct a comparative analysis, MIS-C patients were divided into two groups: patients hospitalized in the ICU (n = 84, 50.6%) and those who did not need ICU admission (n = 82, 49.4%). Patients with a more severe course of MIS-C were significantly older. They had a higher frequency of signs such as rash, swelling, hepatomegaly, splenomegaly, and neurological and respiratory symptoms. Hypotension/shock and myocardial involvement were much more common in patients with severe MIS-C. These patients had a more significant increase in CRP, creatinine, troponin, and D-dimer levels. Additionally, the presence of macrophage activation syndrome was higher in patients admitted to the ICU. Conclusion: Nineteen predictors of severe course of MIS-C were found, out of which hepatomegaly, splenomegaly, D-dimer > 2568 ng/mL, troponin > 10 pg/mL were mainly associated with the probability of being classified as early predictors of severe MIS-C requiring ICU admission.

The protective effect of COVID-19 vaccines on developing multisystem inflammatory syndrome in children (MIS-C): a systematic literature review and meta-analysis

OBJECTIVE

To review whether the current COVID-19 vaccines can prevent the occurrence of multisystem inflammatory syndrome in children (MIS-C) and adolescents.

METHODS

A systematic literature review and meta-analysis were performed. The data were abstracted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Primary outcome was the efficacy of COVID-19 vaccination in preventing MIS-C development. The search was performed in PubMed and Embase.

RESULTS

The review yielded 13 studies, which were included for critical appraisal and data extraction. The available studies showed a reduced incidence of MIS-C after mRNA COVID-19 vaccination in children aged 12-18 years. Four studies were eligible for meta-analysis and the pooled odds ratio for MIS-C in vaccinated children compared to unvaccinated children was 0.04 (95% confidence interval: 0.03-0.06). Additionally, the risk of MIS-C as an adverse effect of vaccination was much lower compared to the risk of MIS-C post-infection.

CONCLUSIONS

Our systematic review highlights the current available evidence on the efficacy of COVID-19 vaccination in preventing MIS-C. The published studies so far - mainly conducted during the Delta wave - indicate that (original strain) COVID-19 mRNA vaccines in children are safe and associated with significantly less development of MIS-C. These findings further reinforce the recommendation for COVID-19 vaccination in children, which should be promoted and largely supported.

The Inflammatory Profile Correlates with COVID-19 Severity and Mortality in Cancer Patients

BACKGROUND

The correlation of the inflammatory profile with the severity of the disease in neoplastic patients with SARS-CoV-2 infection was addressed.

METHODS

A database of 1537 patients hospitalized in the pneumology department was analyzed. After applying the inclusion and exclusion criteria, 83 patients (67% males, 33% females) were included.

RESULTS

Most of the analyzed patients were hospitalized with a moderate form of disease, explaining the significant percentage of 25% mortality. The frequency of the type of neoplasm was higher for lung cancer, followed by malignant colon tumor. We identified a significant association between the increased value of ferritin (p < 0.0001, OR = 22.31), fibrinogen (p = 0.009, OR = 13.41), and C-reactive protein (p = 0.01, OR = 7.65), respectively, and the level of severity of COVID-19. The results of the univariate logistic regression analysis for predicting the severity of the disease revealed that the increased values of ferritin (p = 0.001, OR = 22.31) and fibrinogen (p = 0.02, OR = 13.41) represent a risk for a serious negative prognosis of COVID-19.

CONCLUSIONS

Our study demonstrated that the value of the analyzed inflammatory parameters increased in direct proportion to the severity of the disease and that higher values were associated with increased mortality in the study group.

SARS-CoV-2 infection and recovery in children: Distinct T cell responses in MIS-C compared to COVID-19

SARS-CoV-2 infection for most children results in mild or minimal symptoms, though in rare cases severe disease can develop, including a multisystem inflammatory syndrome (MIS-C) with myocarditis. Here, we present longitudinal profiling of immune responses during acute disease and following recovery in children who developed MIS-C, relative to children who experienced more typical symptoms of COVID-19. T cells in acute MIS-C exhibited transient signatures of activation, inflammation, and tissue residency which correlated with cardiac disease severity, while T cells in acute COVID-19 upregulated markers of follicular helper T cells for promoting antibody production. The resultant memory immune response in recovery showed increased frequencies of virus-specific memory T cells with pro-inflammatory functions in children with prior MIS-C compared to COVID-19 while both cohorts generated comparable antibody responses. Together our results reveal distinct effector and memory T cell responses in pediatric SARS-CoV-2 infection delineated by clinical syndrome, and a potential role for tissue-derived T cells in the immune pathology of systemic disease.

COVID-19-induced gastrointestinal autonomic dysfunction: A systematic review

BACKGROUND

It is common for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to occur in the gastrointestinal tract, which can present itself as an initial symptom. The severity of coronavirus disease 2019 (COVID-19) is often reflected in the prevalence of gastrointestinal symptoms. COVID-19 can damage the nerve supply to the digestive system, leading to gastrointestinal autonomic dysfunction. There is still much to learn about how COVID-19 affects the autonomic nervous system and the gastrointestinal tract.

AIM

To thoroughly explore the epidemiology and clinical aspects of COVID-19-induced gastrointestinal autonomic dysfunction, including its manifestations, potential mechanisms, diagnosis, differential diagnosis, impact on quality of life, prognosis, and management and prevention strategies.

METHODS

We conducted a thorough systematic search across various databases and performed an extensive literature review. Our review encompassed 113 studies published in English from January 2000 to April 18, 2023.

RESULTS

According to most of the literature, gastrointestinal autonomic dysfunction can seriously affect a patient's quality of life and ultimate prognosis. Numerous factors can influence gastrointestinal autonomic nervous functions. Studies have shown that SARS-CoV-2 has a well-documented affinity for both neural and gastrointestinal tissues, and the virus can produce various gastrointestinal symptoms by reaching neural tissues through different pathways. These symptoms include anorexia, dysgeusia, heartburn, belching, chest pain, regurgitation, vomiting, epigastric burn, diarrhea, abdominal pain, bloating, irregular bowel movements, and constipation. Diarrhea is the most prevalent symptom, followed by anorexia, nausea, vomiting, and abdominal pain. Although COVID-19 vaccination may rarely induce autonomic dysfunction and gastrointestinal symptoms, COVID-19-induced autonomic effects significantly impact the patient's condition, general health, prognosis, and quality of life. Early diagnosis and proper recognition are crucial for improving outcomes. It is important to consider the differential diagnosis, as these symptoms may be induced by diseases other than COVID-19-induced autonomic dysfunction. Treating this dysfunction can be a challenging task.

CONCLUSION

To ensure the best possible outcomes for COVID-19 patients, it is essential to take a multidisciplinary approach involving providing supportive care, treating the underlying infection, managing dysfunction, monitoring for complications, and offering nutritional support. Close monitoring of the patient's condition is crucial, and prompt intervention should be taken if necessary. Furthermore, conducting thorough research on the gastrointestinal autonomic dysfunction caused by COVID-19 is vital to manage it effectively.

COVID-19-induced gastrointestinal autonomic dysfunction: A systematic review

BACKGROUND

It is common for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to occur in the gastrointestinal tract, which can present itself as an initial symptom. The severity of coronavirus disease 2019 (COVID-19) is often reflected in the prevalence of gastrointestinal symptoms. COVID-19 can damage the nerve supply to the digestive system, leading to gastrointestinal autonomic dysfunction. There is still much to learn about how COVID-19 affects the autonomic nervous system and the gastrointestinal tract.

AIM

To thoroughly explore the epidemiology and clinical aspects of COVID-19-induced gastrointestinal autonomic dysfunction, including its manifestations, potential mechanisms, diagnosis, differential diagnosis, impact on quality of life, prognosis, and management and prevention strategies.

METHODS

We conducted a thorough systematic search across various databases and performed an extensive literature review. Our review encompassed 113 studies published in English from January 2000 to April 18, 2023.

RESULTS

According to most of the literature, gastrointestinal autonomic dysfunction can seriously affect a patient's quality of life and ultimate prognosis. Numerous factors can influence gastrointestinal autonomic nervous functions. Studies have shown that SARS-CoV-2 has a well-documented affinity for both neural and gastrointestinal tissues, and the virus can produce various gastrointestinal symptoms by reaching neural tissues through different pathways. These symptoms include anorexia, dysgeusia, heartburn, belching, chest pain, regurgitation, vomiting, epigastric burn, diarrhea, abdominal pain, bloating, irregular bowel movements, and constipation. Diarrhea is the most prevalent symptom, followed by anorexia, nausea, vomiting, and abdominal pain. Although COVID-19 vaccination may rarely induce autonomic dysfunction and gastrointestinal symptoms, COVID-19-induced autonomic effects significantly impact the patient's condition, general health, prognosis, and quality of life. Early diagnosis and proper recognition are crucial for improving outcomes. It is important to consider the differential diagnosis, as these symptoms may be induced by diseases other than COVID-19-induced autonomic dysfunction. Treating this dysfunction can be a challenging task.

CONCLUSION

To ensure the best possible outcomes for COVID-19 patients, it is essential to take a multidisciplinary approach involving providing supportive care, treating the underlying infection, managing dysfunction, monitoring for complications, and offering nutritional support. Close monitoring of the patient's condition is crucial, and prompt intervention should be taken if necessary. Furthermore, conducting thorough research on the gastrointestinal autonomic dysfunction caused by COVID-19 is vital to manage it effectively.

Clinical Features and Risk Factors Associated With Multisystem Inflammatory Syndrome in Children With Cancer and COVID-19

Importance

Little is known about the risk of post-COVID-19 multisystem inflammatory syndrome in children (MIS-C) in the setting of childhood cancer.

Objective

To evaluate factors associated with MIS-C and describe the clinical course of COVID-19 in the setting of MIS-C.

Design, Setting, and Participants

Multisite observational cohort study of a registry representing more than 100 US pediatric oncology sites. All included patients were registered between April 1, 2020, and May 18, 2022. Sites submitted deidentified data surrounding sociodemographics, cancer diagnosis and treatment, and COVID-19 course (symptoms, maximum support required, outcome). Patients with MIS-C (n = 24) were compared with matched controls (n = 96). Children (<21 years) with cancer who developed COVID-19 while receiving cancer treatment or within 1 year of completing treatment were characterized based on their development of MIS-C.

Exposures

(1) Clinical and sociodemographic characteristics of children with cancer and COVID-19; and (2) MIS-C.

Main Outcomes and Measures

(1) Development of MIS-C among children with cancer and COVID-19; and (2) symptoms and disease severity associated with MIS-C.

Results

Among 2035 children with cancer and COVID-19, 24 (1.2%) developed MIS-C. COVID-19 occurred at a median (IQR) age of 12.5 (5.5-17.1) years in those with MIS-C and 11 (6-16) years among matched controls (P = .86). The majority of children with MIS-C had a hematologic cancer (83.3% [n = 20]), were publicly insured (66.7% [n = 16]), and were Hispanic (54.2% [n = 13]). Half (n = 12) had 1 or more noncancer comorbidity. Those with comorbidities were more likely to develop MIS-C than those without (odds ratio [OR], 2.5 [95% CI, 1.1-5.7]). Among children with MIS-C, 100% (n = 24) were admitted to the hospital and 54.2% (n = 13) to the intensive care unit (ICU), while COVID-19 contributed to the death of 20.1% (n = 5); cancer therapy was changed in 62.5% (n = 15). Compared with matched controls, those with MIS-C had higher odds of symptoms classified as systemic (OR, 4.7 [95% CI, 1.4-15.8]) or gastrointestinal (OR, 5.0 [95% CI, 1.7-14.6]) along with higher odds of hospitalization (OR, 42.9 [95% CI, 7.1-258]), ICU admission (OR, 11.4 [95% CI, 3.6-36.4]), and changes to cancer therapy (OR, 24.9 [95% CI, 6.5-94.8]).

Conclusions and Relevance

In this cohort study among children with cancer and COVID-19, those with MIS-C had a more severe clinical course than those without MIS-C. The risk of MIS-C and its severity are important to consider as clinicians monitor patients with COVID-19. These findings can inform their conversations with families regarding COVID-19 risks and the benefits of prevention strategies that are pharmacologic (vaccination) and nonpharmacologic (masking), as well as treatment (antivirals, monoclonal antibodies).

Infants Admitted to US Intensive Care Units for RSV Infection During the 2022 Seasonal Peak

Importance

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections (LRTIs) and infant hospitalization worldwide.

Objective

To evaluate the characteristics and outcomes of RSV-related critical illness in US infants during peak 2022 RSV transmission.

Design, Setting, and Participants

This cross-sectional study used a public health prospective surveillance registry in 39 pediatric hospitals across 27 US states. Participants were infants admitted for 24 or more hours between October 17 and December 16, 2022, to a unit providing intensive care due to laboratory-confirmed RSV infection.

Exposure

Respiratory syncytial virus.

Main Outcomes and Measures

Data were captured on demographics, clinical characteristics, signs and symptoms, laboratory values, severity measures, and clinical outcomes, including receipt of noninvasive respiratory support, invasive mechanical ventilation, vasopressors or extracorporeal membrane oxygenation, and death. Mixed-effects multivariable log-binomial regression models were used to assess associations between intubation status and demographic factors, gestational age, and underlying conditions, including hospital as a random effect to account for between-site heterogeneity.

Results

The first 15 to 20 consecutive eligible infants from each site were included for a target sample size of 600. Among the 600 infants, the median (IQR) age was 2.6 (1.4-6.0) months; 361 (60.2%) were male, 169 (28.9%) were born prematurely, and 487 (81.2%) had no underlying medical conditions. Primary reasons for admission included LRTI (594 infants [99.0%]) and apnea or bradycardia (77 infants [12.8%]). Overall, 143 infants (23.8%) received invasive mechanical ventilation (median [IQR], 6.0 [4.0-10.0] days). The highest level of respiratory support for nonintubated infants was high-flow nasal cannula (243 infants [40.5%]), followed by bilevel positive airway pressure (150 infants [25.0%]) and continuous positive airway pressure (52 infants [8.7%]). Infants younger than 3 months, those born prematurely (gestational age <37 weeks), or those publicly insured were at higher risk for intubation. Four infants (0.7%) received extracorporeal membrane oxygenation, and 2 died. The median (IQR) length of hospitalization for survivors was 5 (4-10) days.

Conclusions and Relevance

In this cross-sectional study, most US infants who required intensive care for RSV LRTIs were young, healthy, and born at term. These findings highlight the need for RSV preventive interventions targeting all infants to reduce the burden of severe RSV illness.

Multisystem Inflammatory Syndrome in Children and Kawasaki Disease: A Spectrum of Postinfectious Hyperinflammatory Disease

Kawasaki disease and multisystem inflammatory syndrome in children are hyperinflammatory conditions that share similar emerging pathophysiology hypotheses, clinical features, treatment strategies, and outcomes. Although both conditions have key differences, growing evidence suggests that both conditions might be closely related on a larger spectrum of postinfectious autoimmune responses.

Variation in Early Anakinra Use and Short-Term Outcomes in Multisystem Inflammatory Syndrome in Children

OBJECTIVE

Evidence regarding effectiveness of interleukin-1 receptor antagonism in multisystem inflammatory syndrome in children (MIS-C) is lacking. We characterized variation in initial treatment with anakinra and evaluated cardiovascular outcomes associated with adding anakinra to standard initial therapy.

METHODS

We conducted a retrospective cohort study of MIS-C cases in a US surveillance registry from November 2020 to December 2021. Day 0 was the first calendar day of immunomodulatory treatment. Factors associated with initial anakinra use (days 0-1) were identified. We compared cases in patients ages 2-20 years receiving intravenous immunoglobulin (IVIG) and glucocorticoids versus anakinra plus IVIG and/or glucocorticoids on days 0-1, using inverse probability weighting to balance disease severity. Primary outcomes were vasopressor requirement on day 3 and impaired left ventricular ejection fraction on days 3-4. The secondary outcome was 50% reduction in C-reactive protein on day 3.

RESULTS

Among 1,516 MIS-C cases at 44 sites, 193 (13%) patients received anakinra alone or with other immunomodulators as initial treatment (range 0-74% by site). Site accounted for 59% of residual variance in anakinra use. After balancing disease severity, initial treatment with anakinra plus IVIG and/or glucocorticoids (n = 121) versus IVIG plus glucocorticoids (n = 389) was not associated with significant differences in vasopressor requirement (25.6% versus 20.1%, respectively; risk ratio [RR] 1.27 [95% confidence interval (95% CI) 0.88-1.84]), ventricular dysfunction (33.7% versus 25.7%, respectively; RR 1.31 [95% CI 0.98-1.75]), or C-reactive protein reduction.

CONCLUSION

We identified substantial variation in initial anakinra use in a real-world population of children with MIS-C, but no average short-term improvement in cardiovascular outcomes associated with early addition of anakinra to IVIG and/or glucocorticoids compared to IVIG and glucocorticoids alone.

Multisystem inflammatory syndrome in children: another COVID-19 sequel

With the rapid expansion of the COVID-19 pandemic, the disease burden and its consequences on the paediatric population has been progressively recognised. Although COVID-19 infection in children presents as asymptomatic to mild illness, instances of hyperinflammation and multi-organ involvement following the viral infection have been described. This condition, known as the multisystem inflammatory syndrome in children (MIS-C), has gained a wide global attention. Despite the global efforts to uncover the disease characteristics and management, a clear pathogenesis and a unified treatment regimen have not been reached yet. This paper tackles the epidemiology of the MIS-C, discusses its suggested pathogenesis, drives through its varying clinical presentations, and evaluates the different treatment regimens employed in managing MIS-C.

Evolving trends in inpatient paediatric dermatology

PURPOSE OF REVIEW

This review provides updates in the evaluation and management of key dermatologic diseases encountered in the hospitalized child.

RECENT FINDINGS

Our understanding of dermatologic disorders in children continues to evolve. Staphylococcal scalded skin syndrome (SSSS) is a potentially severe blistering disorder typically seen in children under the age of 4 with an incidence that is increasing in the United States. Recent research has highlighted that the majority of cases are due to methicillin-sensitive Staphylococcus aureus (MSSA) and most patients can be adequately managed with beta-lactams. Toxic epidermal necrolysis (TEN) is one of the most feared dermatologic disorders. Currently, there is a lack of consensus on the most efficacious first-line systemic therapy. Etanercept is increasingly being used based on studies showing a shorter time to re-epithelization and decreased mortality. Lastly, the COVID-19 pandemic introduced the novel inflammatory condition multisystem inflammatory syndrome in children (MIS-C) in which approximately three out of four children present with a mucocutaneous eruption. Early recognition of the dermatologic features of MIS-C is important in potentially establishing a diagnosis and differentiating it from the many other causes of childhood fever and rash.

SUMMARY

There are no clear universal treatment guidelines for these rare diagnoses, and therefore, clinicians must remain informed of the latest findings in diagnosis and therapeutics.

Predicting Delayed Shock in Multisystem Inflammatory Disease in Children: A Multicenter Analysis From the New York City Tri-State Region

OBJECTIVES

Patients with multisystem inflammatory disease in children (MIS-C) are at risk of developing shock. Our objectives were to determine independent predictors associated with development of delayed shock (≥3 hours from emergency department [ED] arrival) in patients with MIS-C and to derive a model predicting those at low risk for delayed shock.

METHODS

We conducted a retrospective cross-sectional study of 22 pediatric EDs in the New York City tri-state area. We included patients meeting World Health Organization criteria for MIS-C and presented April 1 to June 30, 2020. Our main outcomes were to determine the association between clinical and laboratory factors to the development of delayed shock and to derive a laboratory-based prediction model based on identified independent predictors.

RESULTS

Of 248 children with MIS-C, 87 (35%) had shock and 58 (66%) had delayed shock. A C-reactive protein (CRP) level greater than 20 mg/dL (adjusted odds ratio [aOR], 5.3; 95% confidence interval [CI], 2.4-12.1), lymphocyte percent less than 11% (aOR, 3.8; 95% CI, 1.7-8.6), and platelet count less than 220,000/uL (aOR, 4.2; 95% CI, 1.8-9.8) were independently associated with delayed shock. A prediction model including a CRP level less than 6 mg/dL, lymphocyte percent more than 20%, and platelet count more than 260,000/uL, categorized patients with MIS-C at low risk of developing delayed shock (sensitivity 93% [95% CI, 66-100], specificity 38% [95% CI, 22-55]).

CONCLUSIONS

Serum CRP, lymphocyte percent, and platelet count differentiated children at higher and lower risk for developing delayed shock. Use of these data can stratify the risk of progression to shock in patients with MIS-C, providing situational awareness and helping guide their level of care.

Change in Severity and Clinical Manifestation of MIS-C Over SARS-CoV-2 Variant Outbreaks in Korea

BACKGROUND

There is difference in the incidence of multi-system inflammatory syndrome in children (MIS-C) in patients with different variants of severe acute respiratory syndrome coronavirus 2, however, little is known about the epidemiology in Asian countries. We investigated and compared the epidemiology of the MIS-C during omicron-dominant period with that of previous periods in South Korea.

METHODS

We obtained clinical, epidemiological and laboratory data on MIS-C cases from national MIS-C surveillance in South Korea. We defined pre-delta period as January 2020-May 2021; delta period as June 2021-December 2021; and omicron period as January 2022-April 2022. We describe the clinical characteristics and outcomes of MIS-C patients by period.

RESULTS

A total of 91 cases were assessed to be MIS-C cases. Number of MIS-C cases have increased from six cases during pre-delta period to 66 cases during omicron period, while the incidence rate (the number of MIS-C cases per 100,000 cases of reported coronavirus disease 2019) has decreased from 38.5 cases per 100,000 (95% confidence interval [CI], 14.1-83.9) during pre-delta period to 1.6 cases per 100,000 (95% CI, 1.2-2.0) during omicron periods. During pre-delta period, 66.7% and 100% had hypotension and gastrointestinal involvement, respectively; while during omicron period, 12.1% and 6.1% had such clinical manifestations. Fifty percent of pre-delta MIS-C patients were taken intensive care unit (ICU) cares, while 10.6% of patients during omicron periods were in ICUs.

CONCLUSION

Omicron period were associated with less severe clinical manifestation compared to pre-delta and delta periods. Although incidence rate of MIS-C was lower for the omicron period than pre-delta and delta periods, number of patients reported with MIS-C may pose a substantial clinical burden.

Rare genetic variants involved in multisystem inflammatory syndrome in children: a multicenter Brazilian cohort study

Introduction

Despite the existing data on the Multisystem Inflammatory Syndrome in Children (MIS-C), the factors that determine these patients evolution remain elusive. Answers may lie, at least in part, in genetics. It is currently under investigation that MIS-C patients may have an underlying innate error of immunity (IEI), whether of monogenic, digenic, or even oligogenic origin.

Methods

To further investigate this hypothesis, 30 patients with MIS-C were submitted to whole exome sequencing.

Results

Analyses of genes associated with MIS-C, MIS-A, severe covid-19, and Kawasaki disease identified twenty-nine patients with rare potentially damaging variants (50 variants were identified in 38 different genes), including those previously described in IFNA21 and IFIH1 genes, new variants in genes previously described in MIS-C patients (KMT2D, CFB, and PRF1), and variants in genes newly associated to MIS-C such as APOL1, TNFRSF13B, and G6PD. In addition, gene ontology enrichment pointed to the involvement of thirteen major pathways, including complement system, hematopoiesis, immune system development, and type II interferon signaling, that were not yet reported in MIS-C.

Discussion

These data strongly indicate that different gene families may favor MIS- C development. Larger cohort studies with healthy controls and other omics approaches, such as proteomics and RNAseq, will be precious to better understanding the disease dynamics.

Exploring Factors Influencing Changes in Incidence and Severity of Multisystem Inflammatory Syndrome in Children

Multisystem inflammatory syndrome (MIS-C) is a rare condition associated with COVID-19 affecting children, characterized by severe and aberrant systemic inflammation leading to nonspecific symptoms, such as gastrointestinal, cardiac, respiratory, hematological, and neurological disorders. In the last year, we have experienced a progressive reduction in the incidence and severity of MIS-C, reflecting the worldwide trend. Thus, starting from the overall trend in the disease in different continents, we reviewed the literature, hypothesizing the potential influencing factors contributing to the reduction in cases and the severity of MIS-C, particularly the vaccination campaign, the spread of different SARS-CoV-2 variants (VOCs), and the changes in human immunological response. The decrease in the severity of MIS-C and its incidence seem to be related to a combination of different factors rather than a single cause. Maturation of an immunological memory to SARS-CoV-2 over time, the implication of mutations of key amino acids of S protein in VOCs, and the overall immune response elicited by vaccination over the loss of neutralization of vaccines to VOCs seem to play an important role in this change.

Principles of Rational COVID-19 Therapy in Pediatrics

The purpose of this review was to conduct a comparative assessment of the concepts of therapy for pediatric patients with COVID-19 in the framework of global clinical practice. A structural analysis of the range of drugs and treatment strategies in the context of etiotropic, pathogenetic, and symptomatic therapy has shown that in the global context and in real clinical practice, the etiotropic-pathogenetic approach based on information about the effectiveness of individual medical technologies prevails today. It has been established that eight international nonproprietary/grouping names are present in international practice as means of etiotropic therapy for pediatric patients with COVID-19, and 18 positions are used for pathogenetic therapy. In terms of frequency of occurrence, the leading positions are occupied by remdesivir and the combination of nirmatrelvir with ritonavir, as well as dexamethasone and tocilizumab. The paper emphasizes the relevance of research in the field of evaluating the effectiveness of individual treatment regimens as well as the analysis of the delayed consequences of pathology suffered in childhood under the conditions of using various approaches to pharmacotherapy.

[Multisystemic inflammatory syndrome in children after severe acute respiratory syndrome coronavirus 2 infection: a clinical analysis of four cases]

OBJECTIVES

To investigate the clinical features and treatment strategies of multisystemic inflammatory syndrome in children (MIS-C) after severe acute respiratory syndrome coronavirus 2 infection.

METHODS

A retrospective analysis was performed on the medical data of four children with MIS-C who were admitted to the Department of Cardiology, Xuzhou Children's Hospital, Xuzhou Medical Universityfrom January to February 2023.

RESULTS

All four children had multiple organ involvements and elevated inflammatory markers, with a poor response to standard therapy for Kawasaki disease after admission. Two children were treated with intravenous immunoglobulin therapy pulse therapy twice, and all four children were treated with glucocorticoids. The children had a good prognosis after the treatment.

CONCLUSIONS

MIS-C often appears within 4-6 weeks or a longer time after severe acute respiratory syndrome coronavirus 2 infection, and anti-inflammatory therapy in addition to the standard treatment regimen for Kawasaki disease can help to achieve a favorable treatment outcome.

Surveillance for Multisystem Inflammatory Syndrome in US Children Aged 5-11 Years Who Received Pfizer-BioNTech COVID-19 Vaccine, November 2021 through March 2022

Multisystem inflammatory syndrome in children (MIS-C) is a complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; in the United States, reporting of MIS-C after coronavirus disease 2019 (COVID-19) vaccination is required for vaccine safety monitoring. Pfizer-BioNTech COVID-19 vaccine was authorized for children aged 5-11 years on 29 October 2021. Covering a period when approximately 7 million children received vaccine, surveillance for MIS-C ≤ 90 days postvaccination using passive systems identified 58 children with MIS-C and laboratory evidence of past/recent SARS-CoV-2 infection, and 4 without evidence. During a period with extensive SARS-CoV-2 circulation, MIS-C illness in children after COVID-19 vaccination who lacked evidence of SARS-CoV-2 infection was rare (<1 per million vaccinated children).

A framework for future national pediatric pandemic respiratory disease severity triage: The HHS pediatric COVID-19 data challenge

Introduction

With persistent incidence, incomplete vaccination rates, confounding respiratory illnesses, and few therapeutic interventions available, COVID-19 continues to be a burden on the pediatric population. During a surge, it is difficult for hospitals to direct limited healthcare resources effectively. While the overwhelming majority of pediatric infections are mild, there have been life-threatening exceptions that illuminated the need to proactively identify pediatric patients at risk of severe COVID-19 and other respiratory infectious diseases. However, a nationwide capability for developing validated computational tools to identify pediatric patients at risk using real-world data does not exist.

Methods

HHS ASPR BARDA sought, through the power of competition in a challenge, to create computational models to address two clinically important questions using the National COVID Cohort Collaborative: (1) Of pediatric patients who test positive for COVID-19 in an outpatient setting, who are at risk for hospitalization? (2) Of pediatric patients who test positive for COVID-19 and are hospitalized, who are at risk for needing mechanical ventilation or cardiovascular interventions?

Results

This challenge was the first, multi-agency, coordinated computational challenge carried out by the federal government as a response to a public health emergency. Fifty-five computational models were evaluated across both tasks and two winners and three honorable mentions were selected.

Conclusion

This challenge serves as a framework for how the government, research communities, and large data repositories can be brought together to source solutions when resources are strapped during a pandemic.

Seizure as Presenting Symptom of Multisystem Inflammatory Syndrome in Children

We describe the case of a 13-year-old girl who presented with a new-onset seizure and fever and subsequently developed severe cardiac dysfunction, coronary artery dilation, and shock due to the surprising diagnosis of multisystem inflammatory syndrome in children (MIS-C). Although the clinical entity we now call MIS-C was first mentioned in the medical literature in April 2020, the full picture of this disease process is still evolving. Neurologic involvement has been described in cases with MIS-C; however, seizures are not a typical presenting symptom. Additionally, because children infected with SARS-CoV-2 are often asymptomatic, a documented preceding COVID-19 infection might not be available to raise suspicion of MIS-C early on. Febrile seizures, meningitis, and encephalitis are childhood illnesses that pediatricians are generally familiar with, but associating these clinical pictures with MIS-C is uncommon. Given the possibility of rapid clinical cardiogenic decline, as seen in our patient, a prompt diagnosis and appropriate monitoring and treatment are of utmost importance. This case report aims to raise awareness that new-onset seizures with fevers can be early or the first presenting symptoms in children with MIS-C, and further workup and close monitoring may be required.

Risk and Benefit of mRNA COVID-19 Vaccines for the Omicron Variant by Age, Sex, and Presence of Comorbidity: A Quality-Adjusted Life Years Analysis

The development of the mutant omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the coronavirus disease 2019 (COVID-19) pandemic raised the importance of reevaluating the risk and benefit of COVID-19 vaccines. With a decision tree model, we calculated the benefit-risk ratio and the benefit-risk difference of receiving monovalent messenger RNA (mRNA) COVID-19 vaccine (primary 2 doses, a third dose, and a fourth dose) in the 4-5 months after vaccination using quality-adjusted life years. The analysis was stratified by age, sex, and the presence of comorbidity. Evidence from peer-reviewed publications and gray literature was reviewed on September 16, 2022, to inform the study. Benefit-risk ratios for receipt of the BNT162b2 vaccine (Pfizer-BioNTech) ranged from 6.8 for males aged 12-17 years without comorbidity for the primary doses to 221.3 for females aged ≥65 years with comorbidity for the third dose. The benefit-risk ratios for receipt of the mRNA-1273 vaccine (Moderna) ranged from 7.2 for males aged 18-29 years without comorbidity for the primary doses to 101.4 for females aged ≥65 years with comorbidity for the third dose. In all scenarios of the one-way sensitivity analysis, the benefit-risk ratios were more than 1, irrespective of age, sex, comorbidity status, and type of vaccine, for both primary and booster doses. The benefits of mRNA COVID-19 vaccines in protecting against the omicron variant outweigh the risks, irrespective of age, sex, and comorbidity.

Clinical and biological heterogeneity of multisystem inflammatory syndrome in adults following SARS-CoV-2 infection: a case series

Importance

Multisystem inflammatory syndrome in adults (MIS-A) is a poorly understood complication of SARS-CoV-2 infection with significant morbidity and mortality.

Objective

Identify clinical, immunological, and histopathologic features of MIS-A to improve understanding of the pathophysiology and approach to treatment.

Design

Three cases of MIS-A following SARS-CoV-2 infection were clinically identified between October 2021 - March 2022 using the U.S. Centers for Disease Control and Prevention diagnostic criteria. Clinical, laboratory, imaging, and tissue data were assessed.

Findings

All three patients developed acute onset cardiogenic shock and demonstrated elevated inflammatory biomarkers at the time of hospital admission that resolved over time. One case co-occurred with new onset Type 1 diabetes and sepsis. Retrospective analysis of myocardial tissue from one case identified SARS-CoV-2 RNA. All three patients fully recovered with standard of care interventions plus immunomodulatory therapy that included intravenous immunoglobulin, corticosteroids, and in two cases, anakinra.

Conclusion

MIS-A is a severe post-acute sequela of COVID-19 characterized by systemic elevation of inflammatory biomarkers. In this series of three cases, we find that although clinical courses and co-existent diseases vary, even severe presentations have potential for full recovery with prompt recognition and treatment. In addition to cardiogenic shock, glucose intolerance, unmasking of autoimmune disease, and sepsis can be features of MIS-A, and SARS-CoV-2 myocarditis can lead to a similar clinical syndrome.

Neurological and Psychological Sequelae Associated With Multisystem Inflammatory Syndrome in Children

Importance

Acute neurological involvement occurs in some patients with multisystem inflammatory syndrome in children (MIS-C), but few data report neurological and psychological sequelae, and no investigations include direct assessments of cognitive function 6 to 12 months after discharge.

Objective

To characterize neurological, psychological, and quality of life sequelae after MIS-C.

Design, Setting, and Participants

This cross-sectional cohort study was conducted in the US and Canada. Participants included children with MIS-C diagnosed from November 2020 through November 2021, 6 to 12 months after hospital discharge, and their sibling or community controls, when available. Data analysis was performed from August 2022 to May 2023.

Exposure

Diagnosis of MIS-C.

Main Outcomes and Measures

A central study site remotely administered a onetime neurological examination and in-depth neuropsychological assessment including measures of cognition, behavior, quality of life, and daily function. Generalized estimating equations, accounting for matching, assessed for group differences.

Results

Sixty-four patients with MIS-C (mean [SD] age, 11.5 [3.9] years; 20 girls [31%]) and 44 control participants (mean [SD] age, 12.6 [3.7] years; 20 girls [45%]) were enrolled. The MIS-C group exhibited abnormalities on neurological examination more frequently than controls (15 of 61 children [25%] vs 3 of 43 children [7%]; odds ratio, 4.7; 95% CI, 1.3-16.7). Although the 2 groups performed similarly on most cognitive measures, the MIS-C group scored lower on the National Institutes of Health Cognition Toolbox List Sort Working Memory Test, a measure of executive functioning (mean [SD] scores, 96.1 [14.3] vs 103.1 [10.5]). Parents reported worse psychological outcomes in cases compared with controls, particularly higher scores for depression symptoms (mean [SD] scores, 52.6 [13.1] vs 47.8 [9.4]) and somatization (mean [SD] scores, 55.5 [15.5] vs 47.0 [7.6]). Self-reported (mean [SD] scores, 79.6 [13.1] vs 85.5 [12.3]) and parent-reported (mean [SD] scores, 80.3 [15.5] vs 88.6 [13.0]) quality of life scores were also lower in cases than controls.

Conclusions and Relevance

In this cohort study, compared with contemporaneous sibling or community controls, patients with MIS-C had more abnormal neurologic examinations, worse working memory scores, more somatization and depression symptoms, and lower quality of life 6 to 12 months after hospital discharge. Although these findings need to be confirmed in larger studies, enhanced monitoring may be warranted for early identification and treatment of neurological and psychological symptoms.