Treatment of Multisystem Inflammatory Syndrome in Children

First confirmed case of multisystem inflammatory syndrome in adult in Egypt

Key Clinical Message

Our case report demonstrates extremely uncommon data associated with MIS-A, such as cholestatic jaundice, anemia, and quickly progressing pneumonia. IVIG and pulse steroid medications are the best treatments for improving clinical outcomes.

Abstract

We report a case of multiple organ dysfunctions due to MIS-A in an adult with a history of suspected COVID-19. Our case demonstrates extremely uncommon data associated with MIS-A, such as cholestatic jaundice, anemia, and quickly progressing pneumonia. IVIG and pulse steroid medications are the best treatments for improving clinical outcomes.

Multi-Inflammatory Syndrome in Children (MIS-C) in 2023: Is It Time to Forget about It?

Multisystem inflammatory syndrome in children (MIS-C) is defined as a clinically serious condition requiring hospitalization involving fever, multi-system organ dysfunction, and an increase in inflammatory biomarkers. The syndrome was originally described as a post-infectious complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which usually causes COVID-19. During the COVID-19 pandemic, not only did the virus undergo mutations but vaccines against SARS-CoV-2 were also developed. Both these conditions led to a decrease in the incidence of MIS-C. This narrative review summarizes the recent updates for MIS-C, particularly regarding the change in incidence, the link between the SARS-CoV-2 vaccine and MIS-C, and new updates of MIS-C treatments.

Impact of congenital heart disease on outcomes among pediatric patients hospitalized for COVID-19 infection

BACKGROUND

COVID-19 infection is generally regarded as an acute self-limiting illness in children, but it can cause significant morbidity and mortality in both healthy and high-risk children. There are limited data on the outcomes of children with congenital heart disease (CHD) and COVID-19. This study aimed to examine the risks of mortality, in-hospital cardiovascular and non-cardiovascular complications in this patient population.

METHODS

We analyzed data from hospitalized pediatric patients from 2020 using the nationally representative National Inpatient Sample (NIS). Children hospitalized for COVID-19 were included, and weighted data were used to compare in-hospital mortality and morbidities between children with and without CHD.

RESULTS

Out of 36,690 children admitted with a diagnosis of COVID-19 infection(ICD-10 code:U07.1 and B97.29) during calendar year 2020, 1240 (3.4%) had CHD. The risk of mortality in children with CHD was not significantly higher than those without CHD(1.2% vs. 0.8%, p = 0.50), with adjusted OR (aOR) of 1.7 (95% CI: 0.6-5.3). Tachyarrhythmias and heart block were more likely in CHD children with an aOR of 4.2 (95% CI: 1.8-9.9) and aOR of 5.0 (95% CI: 2.4-10.8), respectively. Similarly, respiratory failure [aOR = 2.0 (1.5-2.8)], respiratory failure requiring non-invasive mechanical ventilation [aOR = 2.7 (1.4-5.2)] and invasive mechanical ventilation [aOR = 2.6 (1.6-4.0)], and acute kidney injury [aOR = 3.4 (2.2-5.4)] were all significantly higher among patients with CHD. Median length of hospital stay in children with CHD was longer than those without CHD [5 days (IQR: 2-11) vs. 3 days (IQR: 2-5), p = < 0.001].

CONCLUSIONS

Children with CHD hospitalized with COVID-19 infection were at increased risk of serious cardiovascular and non-cardiovascular adverse clinical outcomes. They also had increased length of hospital stay and utilization of healthcare resources.

Multisystemic Inflammatory Syndrome in Children and Kawasaki Disease: Parallels in Pathogenesis and Treatment

PURPOSE OF REVIEW

Since it first appeared, multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19) has been compared to Kawasaki disease (KD). Although there were early parallels between MIS-C and KD, key differences emerged over time. Here, we aim to compare the pathogenesis, clinical presentation, treatment, and outcomes of MIS-C and KD.

RECENT FINDINGS

In this article, we review and compare MIS-C and KD, highlighting differentiating features. We discuss the epidemiological and immunological factors along with clinical and laboratory features which discern MIS-C from KD. We also compare treatment and our understanding of long-term outcomes. Though parallels exist between MIS-C and KD, distinguishing the two is important for clinical management of patients, counseling about natural history, and determining long-term monitoring. While both MIS-C and KD are characterized by profound inflammation and inflammatory vasculopathy, further study is needed to determine whether they are distinct immunopathogenic disorders.

Extracorporeal Membrane Oxygenation Characteristics and Outcomes in Children and Adolescents With COVID-19 or Multisystem Inflammatory Syndrome Admitted to U.S. ICUs

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) has been used successfully to support adults with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related cardiac or respiratory failure refractory to conventional therapies. Comprehensive reports of children and adolescents with SARS-CoV-2-related ECMO support for conditions, including multisystem inflammatory syndrome in children (MIS-C) and acute COVID-19, are needed.

DESIGN

Case series of patients from the Overcoming COVID-19 public health surveillance registry.

SETTING

Sixty-three hospitals in 32 U.S. states reporting to the registry between March 15, 2020, and December 31, 2021.

PATIENTS

Patients less than 21 years admitted to the ICU meeting Centers for Disease Control criteria for MIS-C or acute COVID-19.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The final cohort included 2,733 patients with MIS-C ( n = 1,530; 37 [2.4%] requiring ECMO) or acute COVID-19 ( n = 1,203; 71 [5.9%] requiring ECMO). ECMO patients in both groups were older than those without ECMO support (MIS-C median 15.4 vs 9.9 yr; acute COVID-19 median 15.3 vs 13.6 yr). The body mass index percentile was similar in the MIS-C ECMO versus no ECMO groups (89.9 vs 85.8; p = 0.22) but higher in the COVID-19 ECMO versus no ECMO groups (98.3 vs 96.5; p = 0.03). Patients on ECMO with MIS-C versus COVID-19 were supported more often with venoarterial ECMO (92% vs 41%) for primary cardiac indications (87% vs 23%), had ECMO initiated earlier (median 1 vs 5 d from hospitalization), shorter ECMO courses (median 3.9 vs 14 d), shorter hospital length of stay (median 20 vs 52 d), lower in-hospital mortality (27% vs 37%), and less major morbidity at discharge in survivors (new tracheostomy, oxygen or mechanical ventilation need or neurologic deficit; 0% vs 11%, 0% vs 20%, and 8% vs 15%, respectively). Most patients with MIS-C requiring ECMO support (87%) were admitted during the pre-Delta (variant B.1.617.2) period, while most patients with acute COVID-19 requiring ECMO support (70%) were admitted during the Delta variant period.

CONCLUSIONS

ECMO support for SARS-CoV-2-related critical illness was uncommon, but type, initiation, and duration of ECMO use in MIS-C and acute COVID-19 were markedly different. Like pre-pandemic pediatric ECMO cohorts, most patients survived to hospital discharge.

Identifying and Validating Pediatric Hospitalizations for MIS-C Through Administrative Data

BACKGROUND

Individual children's hospitals care for a small number of patients with multisystem inflammatory syndrome in children (MIS-C). Administrative databases offer an opportunity to conduct generalizable research; however, identifying patients with MIS-C is challenging.

METHODS

We developed and validated algorithms to identify MIS-C hospitalizations in administrative databases. We developed 10 approaches using diagnostic codes and medication billing data and applied them to the Pediatric Health Information System from January 2020 to August 2021. We reviewed medical records at 7 geographically diverse hospitals to compare potential cases of MIS-C identified by algorithms to each participating hospital's list of patients with MIS-C (used for public health reporting).

RESULTS

The sites had 245 hospitalizations for MIS-C in 2020 and 358 additional MIS-C hospitalizations through August 2021. One algorithm for the identification of cases in 2020 had a sensitivity of 82%, a low false positive rate of 22%, and a positive predictive value (PPV) of 78%. For hospitalizations in 2021, the sensitivity of the MIS-C diagnosis code was 98% with 84% PPV.

CONCLUSION

We developed high-sensitivity algorithms to use for epidemiologic research and high-PPV algorithms for comparative effectiveness research. Accurate algorithms to identify MIS-C hospitalizations can facilitate important research for understanding this novel entity as it evolves during new waves.

Multisystem Inflammatory Syndrome therapies in children (MISTIC): A randomized trial

Background

Multisystem Inflammatory Syndrome in Children (MIS-C), which occurs 2-6 weeks after initial exposure to SARS-CoV-2, was first identified in early 2020 when patients presented with fever and significant inflammation, often requiring management in the intensive care unit. To date, there has been no clinical trial to determine the most effective treatment. This study compares anti-inflammatory treatments that were selected based on current treatments for Kawasaki disease, a coronary artery vasculitis that shares many clinical features with MIS-C.

Methods

This randomized, comparative effectiveness trial of children with MIS-C uses the small N Sequential Multiple Assignment Randomized Trial (snSMART) design for rare diseases to compare multiple therapies within an individual. Study participants were treated first with intravenous immunoglobulin (IVIG), and if needed, subjects were then randomized to one of three additional treatments (steroids, anakinra, or infliximab). Participants were re-randomized to remaining treatments if they did not demonstrate clinical improvement.

Conclusion

This trial continues to enroll eligible participants to determine the most effective therapies in addition to IVIG and best order in which to use them to treat MIS-C.

Trial Registration

NCT04898231.

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.

Immunoglobulin, glucocorticoid, or combination therapy for multisystem inflammatory syndrome in children: a propensity-weighted cohort study

Background

Multisystem inflammatory syndrome in children (MIS-C), a hyperinflammatory condition associated with SARS-CoV-2 infection, has emerged as a serious illness in children worldwide. Immunoglobulin or glucocorticoids, or both, are currently recommended treatments.

Methods

The Best Available Treatment Study evaluated immunomodulatory treatments for MIS-C in an international observational cohort. Analysis of the first 614 patients was previously reported. In this propensity-weighted cohort study, clinical and outcome data from children with suspected or proven MIS-C were collected onto a web-based Research Electronic Data Capture database. After excluding neonates and incomplete or duplicate records, inverse probability weighting was used to compare primary treatments with intravenous immunoglobulin, intravenous immunoglobulin plus glucocorticoids, or glucocorticoids alone, using intravenous immunoglobulin as the reference treatment. Primary outcomes were a composite of inotropic or ventilator support from the second day after treatment initiation, or death, and time to improvement on an ordinal clinical severity scale. Secondary outcomes included treatment escalation, clinical deterioration, fever, and coronary artery aneurysm occurrence and resolution. This study is registered with the ISRCTN registry, ISRCTN69546370.

Findings

We enrolled 2101 children (aged 0 months to 19 years) with clinically diagnosed MIS-C from 39 countries between June 14, 2020, and April 25, 2022, and, following exclusions, 2009 patients were included for analysis (median age 8·0 years [IQR 4·2-11·4], 1191 [59·3%] male and 818 [40·7%] female, and 825 [41·1%] White). 680 (33·8%) patients received primary treatment with intravenous immunoglobulin, 698 (34·7%) with intravenous immunoglobulin plus glucocorticoids, 487 (24·2%) with glucocorticoids alone; 59 (2·9%) patients received other combinations, including biologicals, and 85 (4·2%) patients received no immunomodulators. There were no significant differences between treatments for primary outcomes for the 1586 patients with complete baseline and outcome data that were considered for primary analysis. Adjusted odds ratios for ventilation, inotropic support, or death were 1·09 (95% CI 0·75-1·58; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids and 0·93 (0·58-1·47; corrected p value=1·00) for glucocorticoids alone, versus intravenous immunoglobulin alone. Adjusted average hazard ratios for time to improvement were 1·04 (95% CI 0·91-1·20; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids, and 0·84 (0·70-1·00; corrected p value=0·22) for glucocorticoids alone, versus intravenous immunoglobulin alone. Treatment escalation was less frequent for intravenous immunoglobulin plus glucocorticoids (OR 0·15 [95% CI 0·11-0·20]; p<0·0001) and glucocorticoids alone (0·68 [0·50-0·93]; p=0·014) versus intravenous immunoglobulin alone. Persistent fever (from day 2 onward) was less common with intravenous immunoglobulin plus glucocorticoids compared with either intravenous immunoglobulin alone (OR 0·50 [95% CI 0·38-0·67]; p<0·0001) or glucocorticoids alone (0·63 [0·45-0·88]; p=0·0058). Coronary artery aneurysm occurrence and resolution did not differ significantly between treatment groups.

Interpretation

Recovery rates, including occurrence and resolution of coronary artery aneurysms, were similar for primary treatment with intravenous immunoglobulin when compared to glucocorticoids or intravenous immunoglobulin plus glucocorticoids. Initial treatment with glucocorticoids appears to be a safe alternative to immunoglobulin or combined therapy, and might be advantageous in view of the cost and limited availability of intravenous immunoglobulin in many countries.

Funding

Imperial College London, the European Union's Horizon 2020, Wellcome Trust, the Medical Research Foundation, UK National Institute for Health and Care Research, and National Institutes of Health.

Pediatric coronavirus disease 2019 in Africa

PURPOSE OF REVIEW

Three years into the coronavirus disease 2019 (COVID-19) pandemic, data on pediatric COVID-19 from African settings is limited. Understanding the impact of the pandemic in this setting with a high burden of communicable and noncommunicable diseases is critical to implementing effective interventions in public health programs.

RECENT FINDINGS

More severe COVID-19 has been reported in African settings, with especially infants and children with underlying comorbidities at highest risk for more severe disease. Data on the role of tuberculosis and HIV remain sparse. Compared to better resourced settings more children with multisystem inflammatory disease (MISC) are younger than 5 years and there is higher morbidity in all settings and increased mortality in some settings. Several reports suggest decreasing prevalence and severity of MIS-C disease with subsequent severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variant waves. Whether this decrease continues remains to be determined. Thus far, data on long-COVID in African settings is lacking and urgently needed considering the severity of the disease seen in the African population.

SUMMARY

Considering the differences seen in the severity of disease and short-term outcomes, there is an urgent need to establish long-term outcomes in children with COVID-19 and MIS-C in African children, including lung health assessment.

Methylprednisolone versus intravenous immunoglobulins in children with paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS): an open-label, multicentre, randomised trial

BACKGROUND

The emergence of paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) led to the widespread use of anti-inflammatory treatments in the absence of evidence from randomised controlled trials (RCTs). We aimed to assess the effectiveness of intravenous methylprednisolone compared with intravenous immunoglobulins.

METHODS

This is an open-label, multicentre, two-arm RCT done at ten hospitals in Switzerland in children younger than 18 years hospitalised with PIMS-TS (defined as age <18 years; fever and biochemical evidence of inflammation, and single or multiorgan dysfunction; microbiologically proven or putative contact with SARS-CoV-2; and exclusion of any other probable disease). Patients were randomly assigned 1:1 to intravenous methylprednisolone (10 mg/kg per day for 3 days) or intravenous immunoglobulins (2 g/kg as a single dose). The primary outcome was length of hospital stay censored at day 28, death, or discharge. Secondary outcomes included proportion and duration of organ support. Analyses were done by intention-to-treat. The study was registered with Swiss National Clinical Trials Portal (SNCTP000004720) and ClinicalTrials.gov (NCT04826588).

FINDINGS

Between May 21, 2021, and April 15, 2022, 75 patients with a median age of 9·1 years (IQR 6·2-12·2) were included in the intention-to-treat population (37 in the methylprednisolone group and 38 in the intravenous immunoglobulins group). The median length of hospital stay was 6·0 days (IQR 4·0-8·0) in the methylprednisolone group and 6·0 days (IQR 5·0-8·8) in the intravenous immunoglobulins group (estimated effect size -0·037 of the log10 transformed times, 95% CI -0·13 to 0·065, p=0·42). Fewer patients in the methylprednisolone group (ten [27%] of 37) required respiratory support compared with the intravenous immunoglobulin group (21 [55%] of 38, p=0·025). Need and duration of inotropes, admission to intensive care units, cardiac events after baseline, and major bleeding and thrombotic events were not significantly different between the study groups.

INTERPRETATION

In this RCT, treatment with methylprednisolone in children with PIMS-TS did not significantly affect the length of hospital stay compared with intravenous immunoglobulins. Intravenous methylprednisolone could be an acceptable first-line treatment in children with PIMS-TS.

FUNDING

NOMIS Foundation, Vontobel Foundation, and Gaydoul Foundation.

Comparison of the course of multisystem inflammatory syndrome in children during different pandemic waves

The purpose of this study is to assess the rate, clinical picture, and management of multisystem inflammatory syndrome in children (MIS-C) during the different COVID-19 variants of concern (VOC) domination periods. This was a retrospective analysis of prospectively collected data. The incidence and clinical picture of MIS-C during the original/Alpha (group 1) and Delta/Omicron (Group 2) variant domination periods were compared. Among 108 eligible patients, 74 (68.5%) were hospitalized during the group 1 domination period, and 34 (31.5%) were hospitalized during the group 2 domination period. The median (Me) patient ages were 76 months (interquartile range [IQR] 35-130) and 73 months (IQR 45-118), and 61% and 65% of patients were male, respectively. There was no significant difference in the presence of positive SARS-CoV 2 antibody test results (IgM or IgG) between the groups (84 vs. 90%; p = 0.54).No differences between groups were observed in fever duration prior to admission (Me [IQR]: 5 days [3-6] vs. 5 days [4-6]; p = 0.26) or the presence of mucocutaneous (95 vs. 100%; p = 0.41), circulatory (70.3 vs. 61.8%; p = 0.86), neurological (6.8 vs. 2.9%; p = 0.662), or gastrointestinal symptoms (84 vs. 79%; p = 0.59). Respiratory symptoms were more common in group 2 (70 vs. 91%; p = 0.015). The need for intensive care unit admission was similar in both groups (16.2 vs. 17.6%, p = 1.0). No deaths occurred in the entire cohort. The studied children were characterized by high C-reactive protein and procalcitonin levels, concentrations of ferritin within normal limits, lymphopenia, moderate hypoalbuminemia, and high B-type natriuretic peptide/brain natriuretic peptide (NT-proBNP) concentrations; however, there were no differences between the groups. Intravenous immunoglobulins were administered as a first-line treatment for almost all patients. There was no significant difference in corticosteroid administration between the groups (87% vs. 74%; p = 0.11); however, the summary dose of methylprednisolone was higher in group 2 (Me [IQR]″ 12.6 mg/kg [10.5-17.8] vs. 16.4 mg/kg [13.3-19.5]; p = 0.03). The median length of stay was 11 days [IQR]: [9-14] and 10 days [8-12], respectively (p = 0.065).

CONCLUSION

The clinical course of MIS-C is similar in subsequent pandemic waves; however, the incidence of MIS-C seems to be decreasing.

WHAT IS KNOWN

• The clinical picture of COVID-19 is evolving. Multisystem inflammatory syndrome in children (MIS-C) is a relatively new serious disease connected with SARS-CoV-2 infection, and in subsequent waves of the pandemic, new cases of the disease have been recorded.

WHAT IS NEW

• The clinical picture of MIS-C is not specific, but the course is still severe. • The incidence of MIS-C during the different pandemic waves is decreasing and the diagnosis in the period of lower prevalance is challenging.

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.

The Role of Immunity in the Pathogenesis of SARS-CoV-2 Infection and in the Protection Generated by COVID-19 Vaccines in Different Age Groups

This study aims to review the available data regarding the central role of immunity in combating SARS-CoV-2 infection and in the generation of protection by vaccination against COVID-19 in different age groups. Physiologically, the immune response and the components involved in it are variable, both functionally and quantitatively, in neonates, infants, children, adolescents, and adults. These immunological differences are mirrored during COVID-19 infection and in the post-vaccination period. The outcome of SARS-CoV-2 infection is greatly dependent on the reaction orchestrated by the immune system. This is clearly obvious in relation to the clinical status of COVID-19 infection, which can be symptomless, mild, moderate, or severe. Even the complications of the disease show a proportional pattern in relation to the immune response. On the contrary, the commonly used anti-COVID-19 vaccines generate protective humoral and cellular immunity. The magnitude of this immunity and the components involved in it are discussed in detail. Furthermore, many of the adverse effects of these vaccines can be explained on the basis of immune reactions against the different components of the vaccines. Regarding the appropriate choice of vaccine for different age groups, many factors have to be considered. This is a cornerstone, particularly in the following age groups: 1 day to 5 years, 6 to 11 years, and 12 to 17 years. Many factors are involved in deciding the route, doses, and schedule of vaccination for children. Another important issue in this dilemma is the hesitancy of families in making the decision about whether to vaccinate their children. Added to these difficulties is the choice by health authorities and governments concerning whether to make children's vaccination compulsory. In this respect, although rare and limited, adverse effects of vaccines in children have been detected, some of which, unfortunately, have been serious or even fatal. However, to achieve comprehensive control over COVID-19 in communities, both children and adults have to be vaccinated, as the former group represents a reservoir for viral transmission. The understanding of the various immunological mechanisms involved in SARS-CoV-2 infection and in the preparation and application of its vaccines has given the sciences a great opportunity to further deepen and expand immunological knowledge. This will hopefully be reflected positively on other diseases through gaining an immunological background that may aid in diagnosis and therapy. Humanity is still in continuous conflict with SARS-CoV-2 infection and will be for a while, but the future is expected to be in favor of the prevention and control of this disease.

COVID-19 Positive Versus Negative Complete Kawasaki Disease: A Study from the International Kawasaki Disease Registry

To determine clinical differences for children with complete Kawasaki disease (KD) with and without evidence of preceding SARS-CoV-2 infection. From January 2020, contemporaneous patients with complete KD criteria were classified as either SARS-CoV-2 positive (KDCOVID+; confirmed household exposure, positive PCR and/or serology) or SARS-CoV-2 negative (KDCOVID-; negative testing and no exposure) and compared. Of 744 patients in the International Kawasaki Disease Registry, 52 were KDCOVID- and 61 were KDCOVID+. KDCOVID+ patients were older (median 5.5 vs. 3.7 years; p < 0.001), and all additionally met diagnostic criteria for multisystem inflammatory syndrome in children (MIS-C). They were more likely to have abdominal pain (60% vs. 35%; p = 0.008) and headache (38% vs. 10%; p < 0.001) and had significantly higher CRP, troponin, and BUN/creatinine, and lower hemoglobin, platelets, and lymphocytes. KDCOVID+ patients were more likely to have shock (41% vs. 6%; p < 0.001), ICU admission (62% vs. 10%; p < 0.001), lower left ventricular ejection fraction (mean lowest LVEF 53% vs. 60%; p < 0.001), and to have received inotropic support (60% vs. 10%; p < 0.001). Both groups received IVIG (2 doses in 22% vs. 18%; p = 0.63), but KDCOVID+ were more likely to have received steroids (85% vs. 35%; p < 0.001) and anakinra (60% vs. 10%; p = 0.002). KDCOVID- patients were more likely to have medium/large coronary artery aneurysms (CAA, 12% vs. 0%; p = 0.01). KDCOVID+ patients differ from KDCOVID-, have more severe disease, and greater evidence of myocardial involvement and cardiovascular dysfunction rather than CAA. These patients may be a distinct KD phenotype in the presence of a prevalent specific trigger.

COVID-19 in Latin America: A Snapshot in Time and the Road Ahead

Since its initial detection in Brazil in February 2020, SARS-CoV-2 and the associated COVID-19 pandemic have continued to devastate Latin America. Specific comorbidities, as well as sociodemographic and lifestyle factors that may be more prevalent in underserved areas, have been identified as risk factors for COVID-19 infection or associated adverse outcomes. Dynamics of infections and deaths in Latin America have varied by country and temporally, as has SARS-CoV-2 variant prevalence; however, more recently, the Delta and subsequent Omicron variants have become ubiquitous. Successful pandemic responses have involved robust infection mitigation measures, testing, and smart deployment of healthcare resourcing. While in some Latin American countries up to 90% of the population is fully vaccinated (i.e., 2 doses) against COVID-19, other countries have failed to reach the World Health Organization's 70% target. Continued focus on comprehensive surveillance, strategies to maximize vaccine availability and uptake, and mitigation of collateral damage on other aspects of public health and social services are critical for managing the COVID-19 pandemic. This review summarizes the COVID-19 experience in Latin America, including epidemiology and vaccination. Key learnings and future considerations for the ongoing pandemic response are also discussed.

Recent developments in the immunopathology of COVID-19

There has been an important change in the clinical characteristics and immune profile of Coronavirus disease 2019 (COVID-19) patients during the pandemic thanks to the extensive vaccination programs. Here, we highlight recent studies on COVID-19, from the clinical and immunological characteristics to the protective and risk factors for severity and mortality of COVID-19. The efficacy of the COVID-19 vaccines and potential allergic reactions after administration are also discussed. The occurrence of new variants of concerns such as Omicron BA.2, BA.4, and BA.5 and the global administration of COVID-19 vaccines have changed the clinical scenario of COVID-19. Multisystem inflammatory syndrome in children (MIS-C) may cause severe and heterogeneous disease but with a lower mortality rate. Perturbations in immunity of T cells, B cells, and mast cells, as well as autoantibodies and metabolic reprogramming may contribute to the long-term symptoms of COVID-19. There is conflicting evidence about whether atopic diseases, such as allergic asthma and rhinitis, are associated with a lower susceptibility and better outcomes of COVID-19. At the beginning of pandemic, the European Academy of Allergy and Clinical Immunology (EAACI) developed guidelines that provided timely information for the management of allergic diseases and preventive measures to reduce transmission in the allergic clinics. The global distribution of COVID-19 vaccines and emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with reduced pathogenic potential dramatically decreased the morbidity, severity, and mortality of COVID-19. Nevertheless, breakthrough infection remains a challenge for disease control. Hypersensitivity reactions (HSR) to COVID-19 vaccines are low compared to other vaccines, and these were addressed in EAACI statements that provided indications for the management of allergic reactions, including anaphylaxis to COVID-19 vaccines. We have gained a depth knowledge and experience in the over 2 years since the start of the pandemic, and yet a full eradication of SARS-CoV-2 is not on the horizon. Novel strategies are warranted to prevent severe disease in high-risk groups, the development of MIS-C and long COVID-19.

COVID-19 Vaccination in Pediatrics: Was It Valuable and Successful?

BACKGROUND

The mass vaccination of children against coronavirus 2019 disease (COVID-19) has been frequently debated. The risk-benefit assessment of COVID-19 vaccination versus infection in children has also been debated.

AIM

This systematic review looked for answers to the question "was the vaccination of our children valuable and successful?".

METHODS

The search strategy of different articles in the literature was based on medical subject headings. Screening and selection were based on inclusion/exclusion criteria.

RESULTS AND DISCUSSION

The search results revealed that the majority of the reported adverse events after COVID-19 vaccination in pediatrics were mild to moderate, with few being severe. Injection site discomfort, fever, headache, cough, lethargy, and muscular aches and pains were the most prevalent side effects. Few clinical studies recorded significant side effects, although the majority of these adverse events had nothing to do with vaccination. In terms of efficacy, COVID-19 disease protection was achieved in 90-95% of cases for mRNA vaccines, in 50-80% of cases for inactivated vaccines, and in 58-92% of cases for adenoviral-based vaccines in children and adolescents.

CONCLUSIONS

Based on available data, COVID-19 immunizations appear to be safe for children and adolescents. Furthermore, multiple studies have proven that different types of vaccines can provide excellent protection against COVID-19 in pediatric populations. The efficacy of vaccines against new SARS-CoV-2 variants and the reduction in vaccine-related long-term adverse events are crucial for risk-benefit and cost-effectiveness assessments; therefore, additional safety studies are required to confirm the long-term safety and effectiveness of vaccinations in children.

A cursed goodbye kiss from severe acute respiratory syndrome-coronavirus-2 to its pediatric hosts: multisystem inflammatory syndrome in children

PURPOSE OF REVIEW

We aimed to summarize a novel disease called multisystem inflammatory syndrome in children (MIS-C), which develops several weeks after a severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) illness.

RECENT FINDINGS

Given the rarity of the disease, the question of why a minority of children develop MIS-C is not known. Certain intrinsic susceptibility factors in the host have been described. In addition to hyperinflammation induced by the innate and acquired immune cells, evidence of molecular mimicry was presented for the disease pathogenesis. As there is an increasing number of infected individuals and mass vaccination schedules, concerns regarding the usefulness of the existing diagnostic criteria sets raised.

SUMMARY

Although children are likely to have a milder COVID-19 course compared with adults, MIS-C as a postinfectious and life-threatening complication was reported in the pediatric age. After 2 years of the disease definition, optimal treatment regimes, effective preventive measures, and long-term outcomes are still debated.

Post-COVID Multisystem Inflammatory Syndrome-Adult Leading to Cardiomyopathy and Autoimmune Thyroiditis: A Case Report

The Coronavirus disease pandemic is an evolving disease with myriad presentations and sequelae. Multisystem inflammatory syndrome in adults (MIS-A) can affect various organ systems, including cardiovascular, gastrointestinal, and neurologic systems, with fever and abnormally increased inflammatory markers without significant respiratory affection. This is a well-known complication in children (MIS-C). Validated clinical criteria are used to diagnose this condition. Long-term sequelae of MIS-A are unclear and underreported. Here, we describe a case of Post-COVID-19 MIS-A who presented with cardiac dysfunction, hepatitis, and acute kidney injury and recovered well with steroids. He was left with persistent cardiomyopathy and thyroiditis with hypothyroidism which to date has not fully recovered. This case emphasizes that the sequelae of COVID-19 and its pathophysiology are not fully understood, and more research is needed to predict and prevent the same.

Multisystem Inflammatory Syndrome in Children (MIS-C) temporally related to COVID-19: the experience at a pediatric reference hospital in Colombia

Abstract Objective: This study aimed to describe the clinical characteristics and the different phenotypes of children with multisystem inflammatory syndrome in children (MIS-C) temporally related to COVID-19 and to evaluate the risk conditions that favored a greater severity of the disease during a 12-month period at a pediatric reference hospital in Colombia. Methods: A 12-month retrospective observational study of children under the age of 18 years who met criteria for MIS-C. Results: A total of 28 children presented MIS-C criteria. The median age was 7 years. Other than fever (100%) (onset 4 days prior to admission), the most frequent clinical features were gastrointestinal (86%) and mucocutaneous (61%). Notably, 14 (50%) children had Kawasaki-like symptoms. The most frequent echocardiographic abnormalities were pericardial effusion (64%), valvular involvement (68%), ventricular dysfunction (39%), and coronary artery abnormalities (29%). In addition, 75% had lymphopenia. All had at least one abnormal coagulation test. Most received intravenous immunoglobulin (89%), glucocorticoids (82%), vasopressors (54%), and antibiotics (64%). Notably, 61% had a more severe form of the disease and were admitted to an intensive care unit (median 4 days, mean 6 days); the severity predictors were patients with the inflammatory/MIS-C phenotype (OR 26.5; 95%CI 1.40–503.7; p=0.029) and rash (OR 14.7; 95%CI 1.2–178.7; p=0.034). Two patients had macrophage activation syndrome. Conclusions: Coronary artery abnormalities, ventricular dysfunction, and intensive care unit admission were frequent, which needs to highlight the importance of early clinical suspicion.

Treatments for multi-system inflammatory syndrome in children - discharge, fever, and second-line therapies

Scarce evidence exists about the best treatment for multi-system inflammatory syndrome (MIS-C). We analyzed the effects of steroids, intravenous immunoglobulin (IVIG), and their combination on the probability of discharge over time, the probability of switching to second-line treatment over time, and the persistence of fever 2 days after treatment. We did a retrospective study to investigate the effect of different treatments on children with MIS-C from 1 March 2020 to 1 June 2021. We estimated the time-to-event probability using a Cox model weighted by propensity score to balance the baseline characteristics. Thirty of 132 (22.7%) patients were initially treated with steroids alone, 29/132 (21.9%) with IVIG alone, and 73/132 (55%) with IVIG plus steroids. The probability of early discharge was higher with IVIG than with IVIG plus steroids (hazard ratio [HR] 1.65, 95% CI 1.11-2.45, p = 0.013), but with a higher probability of needing second-line therapy compared to IVIG plus steroids (HR 3.05, 95% CI 1.12-8.25, p = 0.028). Patients on IVIG had a higher likelihood of persistent fever than patients on steroids (odds ratio [OR] 4.23, 95% CI 1.43-13.5, p = 0.011) or on IVIG plus steroids (OR 4.4, 95% CI 2.05-9.82, p < 0.001). No differences were found for this endpoint between steroids or steroids plus IVIG.    Conclusions: The benefits of each approach may vary depending on the outcome assessed. IVIG seemed to increase the probability of earlier discharge over time but also of needing second-line treatment over time. Steroids seemed to reduce persistent fever, and combination therapy reduced the need for escalating treatment. What is Known: • Steroids plus intravenous immunoglobulin, compared with intravenous immunoglobulin alone for multi-system inflammatory syndrome (MIS-C) might reduce the need for hemodynamic support and the duration of fever, but the certainty of the evidence is low. What is New: • Intravenous immunoglobulin, steroids, and their combination for MIS-C may have different outcomes. • In this study, intravenous immunoglobulin increased the probability of discharge over time, steroids reduced persistent fever, while combination therapy reduced the need for second-line treatments.

Clinical characteristics and short-term outcomes of multisystem inflammatory syndrome in a country with a high prevalence of KD

BACKGROUND

The COVID-19 pandemic has spread continuously. Multisystem inflammatory syndrome in children (MIS-C), like Kawasaki disease (KD), is a potentially severe illness in children that appears to be a delayed, post-infectious complication of COVID-19. However, based on the relatively low MIS-C prevalence and high KD prevalence in Asian children, the clinical features of MIS-C are not fully recognized, especially after the spread of the Omicron variant. Here, we aimed to identify the clinical characteristics of MIS-C in a country with high KD prevalence.

METHODS

We retrospectively analyzed 98 children diagnosed with KD and MIS-C admitted to Jeonbuk National University Hospital between January 1, 2021, and October 15, 2022. Twenty-two patients were diagnosed with MIS-C, following CDC diagnostic criteria for MIS-C. We reviewed medical records for clinical features, laboratory findings, and echocardiography.

RESULTS

Age, height, and weight were higher for patients with MIS-C than for those with KD. Lymphocytes percentage was lower, and the segmented neutrophil percentage was higher in the MIS-C group. The inflammation marker C-reactive protein was higher in the MIS-C group. Prothrombin time was prolonged in the MIS-C group. Albumin level was lower in the MIS-C group. The MIS-C group had lower potassium, phosphorus, chloride, and total calcium. Twenty-five percent of patients diagnosed with MIS-C had positive RT-PCR, and all the patients were N-type SARS-CoV-2 antibody-positive. Albumin ≤3.85 g/dl effectively predicted MIS-C. Regarding echocardiography, the right coronary artery z-score, the absolute value of apical 4-chamber left ventricle longitudinal strain, and the ejection fraction (EF) was significantly lower in the MIS-C group. A month after diagnosis using echocardiographic data, all coronary artery z-scores had reduced significantly. EF and fractional shortening (FS) also improved one month after diagnosis.

CONCLUSION

Albumin values can differentiate MIS-C and KD. In addition, a decrease in the absolute LV longitudinal strain value, EF, and FS was observed in the MIS-C group using echocardiography. Coronary artery dilatation was not evident at the initial diagnosis; however, a change in coronary artery size, EF, and FS was observed on follow-up echocardiography a month after diagnosis.

Pathogenesis, immunology, and immune-targeted management of the multisystem inflammatory syndrome in children (MIS-C) or pediatric inflammatory multisystem syndrome (PIMS): EAACI Position Paper

Multisystem inflammatory syndrome in children (MIS-C) is a rare, but severe complication of coronavirus disease 2019 (COVID-19). It develops approximately 4 weeks after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and involves hyperinflammation with multisystem injury, commonly progressing to shock. The exact pathomechanism of MIS-C is not known, but immunological dysregulation leading to cytokine storm plays a central role. In response to the emergence of MIS-C, the European Academy of Allergy and Clinical Immunology (EAACI) established a task force (TF) within the Immunology Section in May 2021. With the use of an online Delphi process, TF formulated clinical statements regarding immunological background of MIS-C, diagnosis, treatment, follow-up, and the role of COVID-19 vaccinations. MIS-C case definition is broad, and diagnosis is made based on clinical presentation. The immunological mechanism leading to MIS-C is unclear and depends on activating multiple pathways leading to hyperinflammation. Current management of MIS-C relies on supportive care in combination with immunosuppressive and/or immunomodulatory agents. The most frequently used agents are systemic steroids and intravenous immunoglobulin. Despite good overall short-term outcome, MIS-C patients should be followed-up at regular intervals after discharge, focusing on cardiac disease, organ damage, and inflammatory activity. COVID-19 vaccination is a safe and effective measure to prevent MIS-C. In anticipation of further research, we propose a convenient and clinically practical algorithm for managing MIS-C developed by the Immunology Section of the EAACI.

Multicentre observational study on multisystem inflammatory syndrome related to COVID-19 in Argentina

BACKGROUND

The impact of the pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in low- and middle-income countries remains poorly understood. Our aim was to understand the characteristics and outcomes of PIMS-TS in Argentina.

METHODS

This observational, prospective, and retrospective multicenter study enrolled patients younger than 18 years-old manifesting PIMS-TS, Kawasaki disease (KD) or Kawasaki shock syndrome (KSS) between March 2020 and May 2021. Patients were followed-up until hospital discharge or death (one case). The primary outcome was pediatric intensive care unit (PICU) admission. Multiple logistic regression was used to identify variables predicting PICU admission.

RESULTS

Eighty-one percent, 82%, and 14% of the 176 enrolled patients fulfilled the suspect case criteria for PIMS-TS, KD, and KSS, respectively. Temporal association with SARS-CoV-2 was confirmed in 85% of the patients and 38% were admitted to the PICU. The more common clinical manifestations were fever, abdominal pain, rash, and conjunctival injection. Lymphopenia was more common among PICU-admitted patients (87% vs. 51%, p < 0.0001), who also showed a lower platelet count and higher plasmatic levels of inflammatory and cardiac markers. Mitral valve insufficiency, left ventricular wall motion alterations, pericardial effusion, and coronary artery alterations were observed in 30%, 30%, 19.8%, and 18.6% of the patients, respectively. Days to initiation of treatment, rash, lymphopenia, and low platelet count were significant independent contributions to PICU admission.

CONCLUSION

Rates of severe outcomes of PIMS-TS in the present study agreed with those observed in high-income countries. Together with other published studies, this work helps clinicians to better understand this novel clinical entity.

Methylprednisolone pulses as an initial treatment in hyperinflammatory syndrome after COVID-19 in children: evaluation of laboratory data, serial echocardiography and outcome: a case series

BACKGROUND

Hyper-inflammatory syndrome in children and young adult occur 2-6 weeks after COVID-19 infection or closed contact with COVID-19 persons. In this study, the laboratory data and echocardiography and abdominal ultrasonography assessments were evaluated before and after Methylprednisolone pulse as an initial treatment of hyper-inflammatory syndrome. Therefore, the aim of this study is to assessment the clinical manifestations and laboratory data and outcome after methylprednisolone pulse as an initial treatment.

METHOD

In this retrospective study, the demographic status, clinical features, laboratory data, echocardiography, abdominal ultrasound, treatment and outcome of 31 pediatric patients under 16 years old, with inflammatory process after COVID-19 were evaluated. The clinical assessments, laboratory data, sonography and echocardiography were evaluated before and after methylprednisolone pulse. The patients were divided in two age group < and ≥ 7 years old and the clinical manifestations were compared with each other. The Mann-Whitney U test was used to assess the difference in quantitative variables between two groups. To compare pre- and post- treatment values, Wilcoxol test was used. To assess the correlation between qualitative variables chi-square test was used. The level of significant was considered 0.05. These patients with fever and hyper-inflammation features admitted to the referral pediatric rheumatology ward in Children Medical Center of Tehran University of medical sciences, from April 2020 to May 2021 were assessed.

RESULT

The mean age ± SD were (5.94 ± 3) and 51.6% (16) patients were male and 48.4% (15) patients were female. The most documented of previous COVID infection were antibody positive in about 27 (87%) patients. Moreover, 1 (3.8%) was PCR positive, 2 (7.7%) were positive in both PCR and serology and 3(11.5%) had closed contact with COVID-19 patients. About 9(29%) of patients were admitted in Intensive Care Unit (ICU). There were significant correlation between days of delay in starting treatment and ICU admission (P-value = 0.02). The mortality rate was negative in patients and no re-hospitalization was documented. There were significant differences (P-value < 0.05) between lymphocytes, platelet, Erythrocyte Sedimentation rate, C-reactive protein, Aspartate transaminase, Alanine transaminase and ferritin before and after treatment. Skin rashes and cardiac involvement totally as carditis (myocarditis, vulvulitis and pericarditis) (33.3%) and coronary involvements (53.3%) were the most prominent initial presentation in patients. There were near significant correlation (P-value = 0.066) between ferritin level and carditis before treatment. Cervical lymphadenopathy was seen significantly more in ≥ 7 years old (P-value = 0.01).

CONCLUSION

Multisystem inflammatory system in children as a hyperinflammatory syndrome could be treated with first step methylprednisolone pulse with decreasing inflammation in laboratory data and cardiac involvements and good outcome. Furthermore, the ferritin level may be one of the predictor of severe hyper-inflammatory syndrome leading to aggressive and urgent treatment with methylprednisolone pulse.

Council of State and Territorial Epidemiologists/CDC Surveillance Case Definition for Multisystem Inflammatory Syndrome in Children Associated with SARS-CoV-2 Infection - United States

Since May 14, 2020, CDC has conducted national surveillance for multisystem inflammatory syndrome in children (MIS-C) associated with infection with SARS-CoV-2, the virus that causes COVID-19, among persons aged <21 years using a CDC case definition based on public health need and data from early reports of patients with this condition. Recent analyses of accumulated data indicated that certain criteria from the 2020 CDC MIS-C case definition performed better than others in distinguishing MIS-C from other illnesses and that certain other criteria likely contributed to misclassification. To incorporate lessons learned from MIS-C surveillance and public health investigations and to improve feasibility of implementation by surveillance staff at state, local, territorial, and tribal health departments, the Council of State and Territorial Epidemiologists (CSTE) and CDC developed a CSTE/CDC position statement (approved by CSTE in 2022) that includes an MIS-C surveillance case definition for voluntary reporting to CDC (effective January 1, 2023)

This report summarizes the evidence and rationale supporting the components of the CSTE/CDC MIS-C surveillance case definition and describes the methods used to develop the definition. These methods included convening MIS-C clinical experts (i.e., consultants)

regarding identification of MIS-C and its distinction from other pediatric conditions, a review of available literature comparing MIS-C phenotype with that of pediatric COVID-19 and other hyperinflammatory syndromes, and retrospective application of different criteria to data from MIS-C cases previously reported to CDC.

The CSTE/CDC surveillance case definition for MIS-C includes four important changes, in comparison with the 2020 CDC MIS-C case definition. These changes are 1) no required duration of subjective or measured fever; 2) requirement of C-reactive protein ≥3.0 mg/dL to indicate systemic inflammation; 3) adjustments to criteria of organ system involvement to include addition of shock as a separate category and elimination of respiratory, neurologic, and renal criteria; and 4) new requirements on timing of positive SARS-CoV-2 laboratory testing relative to the MIS-C illness. Although MIS-C is not a nationally notifiable condition and reporting is voluntary, CSTE and CDC recommend that all states and territories report all cases meeting confirmed, probable, or suspect criteria of the CSTE/CDC MIS-C surveillance case definition beginning January 1, 2023, for cases with MIS-C illness onset on or after that date

Initial Immunomodulation and Outcome of Children with Multisystem Inflammatory Syndrome Related to COVID-19: A Multisite Study from India

OBJECTIVE

To determine the outcomes in children with MIS-C receiving different immunomodulatory treatment.

METHODS

In this multicentric, retrospective cohort study, data regarding treatment and outcomes of children meeting the WHO case definition for MIS-C, were collected. The primary composite outcome was the requirement of vasoactive/inotropic support on day 2 or beyond or need of mechanical ventilation on day 2 or beyond after initiation of immunomodulatory treatment or death during hospitalization in the treatment groups. Logistic regression and propensity score matching analyses were used to compare the outcomes in different treatment arms based on the initial immunomodulation, i.e., IVIG alone, IVIG plus steroids, and steroids alone.

RESULTS

The data of 368 children (diagnosed between April 2020 and June 2021) meeting the WHO case definition for MIS-C, were analyzed. Of the 368 subjects, 28 received IVIG alone, 82 received steroids alone, 237 received IVIG and steroids, and 21 did not receive any immunomodulation. One hundred fifty-six (42.39%) children had the primary outcome. On logistic regression analysis, the treatment group was not associated with the primary outcome; only the children with shock at diagnosis had higher odds for the occurrence of the outcome [OR (95% CI): 11.4 (5.19-25.0), p < 0.001]. On propensity score matching analysis, the primary outcome was comparable in steroid (n = 45), and IVIG plus steroid (n = 84) groups (p = 0.515).

CONCLUSION

While no significant difference was observed in the frequency of occurrence of the primary outcome in different treatment groups, data from adequately powered RCTs are required for definitive recommendations.

Fifteen-minute consultation: An approach to the management of PIMS-TS in a district general hospital

The COVID-19 pandemic has caused significant disease across the globe but children seem to be much less affected than adults. Coincidentally with the first wave of the pandemic, a cluster of children with fever, hyperinflammation and shock were identified, and this was first described as paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) by the Royal College of Paediatrics and Child Health. Patients with this novel condition were transferred to tertiary centres for management, increasing the pressure in these hospitals that were already extremely busy. There are multiple challenges related to the identification of patients presenting with PIMS-TS given that they mimic multiple other well-known paediatric conditions, like Kawasaki disease and toxic shock syndrome. Investigations and admission criteria to a district general hospital (DGH) need to be well established, and clear guidance should be available for easy decision making in a busy paediatric emergency department. Furthermore, these children can deteriorate suddenly and rapidly; close monitoring is vital, and any deterioration must be taken seriously and addressed immediately. All children who present severely ill, with shock and multiorgan failure, should be retrieved to a paediatric intensive care unit. As our knowledge of the condition has developed, more patients are now managed in a DGH, with virtual multidisciplinary team involvement. This paper outlines a structured approach to management of children presenting with suspected PIMS-TS in a DGH.

Multisystem Inflammatory Syndrome in Children in Western Countries? Decreasing Incidence as the Pandemic Progresses?: An Observational Multicenter International Cross-sectional Study

BACKGROUND

SARS-CoV-2 variations as well as immune protection after previous infections and/or vaccination may have altered the incidence of multisystemic inflammatory syndrome in children (MIS-C). We aimed to report an international time-series analysis of the incidence of MIS-C to determine if there was a shift in the regions or countries included into the study.

METHODS

This is a multicenter, international, cross-sectional study. We collected the MIS-C incidence from the participant regions and countries for the period July 2020 to November 2021. We assessed the ratio between MIS-C cases and COVID-19 pediatric cases in children <18 years diagnosed 4 weeks earlier (average time for the temporal association observed in this disease) for the study period. We performed a binomial regression analysis for 8 participating sites [Bogotá (Colombia), Chile, Costa Rica, Lazio (Italy), Mexico DF, Panama, The Netherlands and Catalonia (Spain)].

RESULTS

We included 904 cases of MIS-C, among a reference population of 17,906,432 children. We estimated a global significant decrease trend ratio in MIS-C cases/COVID-19 diagnosed cases in the previous month ( P < 0.001). When analyzing separately each of the sites, Chile and The Netherlands maintained a significant decrease trend ( P < 0.001), but this ratio was not statistically significant for the rest of sites.

CONCLUSIONS

To our knowledge, this is the first international study describing a global reduction in the trend of the MIS-C incidence during the pandemic. COVID-19 vaccination and other factors possibly linked to the virus itself and/or community transmission may have played a role in preventing new MIS-C cases.

Management of Multisystem Inflammatory Syndrome in Children: Decision-Making Regarding a New Condition in the Absence of Clinical Trial Data

Multisystem inflammatory syndrome in children (MIS-C) is a new illness that evolved during the COVID-19 pandemic with initial reports of severe disease including use of extracorporeal membrane oxygenation and death. Institutions rapidly assembled task forces to develop treatment algorithms. At the national/international levels, collaboratives and associations assembled consensus writing groups to draft guidelines. These guidelines and algorithms were initially on the basis of expert opinion and small case series. Some groups used the Delphi approach, and the resultant guidelines often mimicked those for other conditions that resembled MIS-C, like Kawasaki disease (KD). For instance, intravenous immunoglobulin (IVIG), a known effective treatment for KD, was recommended for MIS-C. Early in the pandemic many favoured IVIG over steroids as first-line therapy. As evidence evolved so did some guidelines, which now endorse the dual use of IVIG with steroids as first-line therapy. In contrast, withholding immunotherapy became an option for some MIS-C patients with mild symptoms. Herein, we review guidelines and discuss the evidence informing early recommendations, how this has evolved, the role and limitations of expert opinion and observational data, and the importance of leveraging existing research infrastructures, such as the intensive care unit collaborative (Overcoming COVID-19 surveillance registry), and the International Kawasaki Disease Registry. Finally, we discuss strategies to rapidly develop, deploy, and adapt clinical trials evaluating the treatment of such rare conditions in children, which might include alternatives to conventional clinical trial design. The emergence of MIS-C during the COVID-19 pandemic has highlighted unmet needs regarding research of a new condition.

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.

Evidence, detailed characterization and clinical context of complement activation in acute multisystem inflammatory syndrome in children

Multisystem inflammatory syndrome in children (MIS-C) is a rare, life-threatening complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. MIS-C develops with high fever, marked inflammation and shock-like picture several weeks after exposure to, or mild infection with SARS-CoV-2. Deep immune profiling identified activated macrophages, neutrophils, B-plasmablasts and CD8 + T cells as key determinants of pathogenesis together with multiple inflammatory markers. The disease rapidly responds to intravenous immunoglobulin (IVIG) treatment with clear changes of immune features. Here we present the results of a comprehensive analysis of the complement system in the context of MIS-C activity and describe characteristic changes during IVIG treatment. We show that activation markers of the classical, alternative and terminal pathways are highly elevated, that the activation is largely independent of anti-SARS-CoV-2 humoral immune response, but is strongly associated with markers of macrophage activation. Decrease of complement activation is closely associated with rapid improvement of MIS-C after IVIG treatment.

Characteristics and Outcomes of Critically Ill Children With Multisystem Inflammatory Syndrome

OBJECTIVES

To characterize the prevalence of pediatric critical illness from multisystem inflammatory syndrome in children (MIS-C) and to assess the influence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain on outcomes.

DESIGN

Retrospective cohort study.

SETTING

Database evaluation using the Virtual Pediatric Systems Database.

PATIENTS

All children with MIS-C admitted to the PICU in 115 contributing hospitals between January 1, 2020, and June 30, 2021.

MEASUREMENTS AND MAIN RESULTS

Of the 145,580 children admitted to the PICU during the study period, 1,338 children (0.9%) were admitted with MIS-C with the largest numbers of children admitted in quarter 1 (Q1) of 2021 ( n = 626). The original SARS-CoV-2 viral strain and the D614G Strain were the predominant strains through 2020, with Alpha B.1.1.7 predominating in Q1 and quarter 2 (Q2) of 2021. Overall, the median PICU length of stay (LOS) was 2.7 days (25-75% interquartile range [IQR], 1.6-4.7 d) with a median hospital LOS of 6.6 days (25-75% IQR, 4.7-9.3 d); 15.2% received mechanical ventilation with a median duration of mechanical ventilation of 3.1 days (25-75% IQR, 1.9-5.8 d), and there were 11 hospital deaths. During the study period, there was a significant decrease in the median PICU and hospital LOS and a decrease in the frequency of mechanical ventilation, with the most significant decrease occurring between quarter 3 and quarter 4 (Q4) of 2020. Children admitted to a PICU from the general care floor or from another ICU/step-down unit had longer PICU LOS than those admitted directly from an emergency department.

CONCLUSIONS

Overall mortality from MIS-C was low, but the disease burden was high. There was a peak in MIS-C cases during Q1 of 2021, following a shift in viral strains in Q1 of 2021. However, an improvement in MIS-C outcomes starting in Q4 of 2020 suggests that viral strain was not the driving factor for outcomes in this population.

Cardiovascular injury and clinical features of multisystem inflammatory syndrome in children (MIS-C) related to Covid-19 in Vietnam

BACKGROUND

This study aimed to describe the cardiovascular injury and clinical features of multisystem inflammatory syndrome in children (MIS-C) related to coronavirus disease 2019 (COVID-19) in Ho Chi Minh City, Vietnam.

METHODS

This was a retrospective cohort study of children with MIS-C (from September 1, 2021 to February 28, 2022) in Children's Hospital 1, Ho Chi Minh City. Demographics, clinical history, significant underlying conditions, clinical manifestations, laboratory investigations, and medical management were analyzed.

RESULTS

A total of 76 patients were included (median age, 5.9 years old, 2 months-16 years). The male/female ratio was 1.6/1. Most patients (75/76) had no previous medical conditions. The mean time from acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to symptom onset was 39 days. During an acute SARS-CoV-2 infection, these patients are either asymptomatic or mildly symptomatic. In addition to fever, gastrointestinal symptoms were also prominent, as observed in our study, with 75%, 73.7%, and 72.3% of patients presenting with abdominal pain, vomiting, and loose stools, respectively. The levels of inflammatory markers increased upon admission and returned to normal levels after treatment. Echocardiography revealed decreased myocardial contractility and coronary injury in 16 (21.1%) and 32 (42.1%) patients, respectively. Most cases (72/76) had no fever within 3 days of intravenous immunoglobulin (IVIG) and methylprednisolone treatment. No deaths occurred in this study. The mean duration of hospitalization was 7.2 days.

CONCLUSION

Cardiovascular involvement was observed in approximately 53.9% of the patients. Anti-inflammatory treatment with IVIG and methylprednisolone had a favorable short-term outcome. However, long-term follow-up studies on post-discharge MIS-C cases are needed to make appropriate treatment recommendations in the acute phase.

Postdischarge Glucocorticoid Use and Clinical Outcomes of Multisystem Inflammatory Syndrome in Children

IMPORTANCE

Minimal data are available regarding the postdischarge treatment of multisystem inflammatory syndrome in children (MIS-C).

OBJECTIVES

To evaluate clinical characteristics associated with duration of postdischarge glucocorticoid use and assess postdischarge clinical course, laboratory test result trajectories, and adverse events in a multicenter cohort with MIS-C.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included patients with MIS-C hospitalized with severe illness and followed up for 3 months in an ambulatory setting. Patients younger than 21 years who were admitted between May 15, 2020, and May 31, 2021, at 13 US hospitals were included. Inclusion criteria were inpatient treatment comprising intravenous immunoglobulin, diagnosis of cardiovascular dysfunction (vasopressor requirement or left ventricular ejection fraction ≤55%), and availability of complete outpatient data for 3 months.

EXPOSURES

Glucocorticoid treatment.

MAIN OUTCOMES AND MEASURES

Main outcomes were patient characteristics associated with postdischarge glucocorticoid treatment, laboratory test result trajectories, and adverse events. Multivariable regression was used to evaluate factors associated with postdischarge weight gain (≥2 kg in 3 months) and hyperglycemia during illness.

RESULTS

Among 186 patients, the median age was 10.4 years (IQR, 6.7-14.2 years); most were male (107 [57.5%]), Black non-Hispanic (60 [32.3%]), and Hispanic or Latino (59 [31.7%]). Most children were critically ill (intensive care unit admission, 163 [87.6%]; vasopressor receipt, 134 [72.0%]) and received inpatient glucocorticoid treatment (178 [95.7%]). Most were discharged with continued glucocorticoid treatment (173 [93.0%]); median discharge dose was 42 mg/d (IQR, 30-60 mg/d) or 1.1 mg/kg/d (IQR, 0.7-1.7 mg/kg/d). Inpatient severity of illness was not associated with duration of postdischarge glucocorticoid treatment. Outpatient treatment duration varied (median, 23 days; IQR, 15-32 days). Time to normalization of C-reactive protein and ferritin levels was similar for glucocorticoid duration of less than 3 weeks vs 3 or more weeks. Readmission occurred in 7 patients (3.8%); none was for cardiovascular dysfunction. Hyperglycemia developed in 14 patients (8.1%). Seventy-five patients (43%) gained 2 kg or more after discharge (median 4.1 kg; IQR, 3.0-6.0 kg). Inpatient high-dose intravenous and oral glucocorticoid therapy was associated with postdischarge weight gain (adjusted odds ratio, 6.91; 95% CI, 1.92-24.91).

CONCLUSIONS AND RELEVANCE

In this multicenter cohort of patients with MIS-C and cardiovascular dysfunction, postdischarge glucocorticoid treatment was often prolonged, but clinical outcomes were similar in patients prescribed shorter courses. Outpatient weight gain was common. Readmission was infrequent, with none for cardiovascular dysfunction. These findings suggest that strategies are needed to optimize postdischarge glucocorticoid courses for patients with MIS-C.

Cardiac involvement in Multisystem Inflammatory Syndrome in Children cases

Multisystem Inflammatory Syndrome in Children is a rare form of COVID-19 that affects various organ systems and carries the risk of morbidity and mortality. Cardiac involvement is commonly observed in Multisystem Inflammatory Syndrome in Children cases; hence, this study was conducted to evaluate the cardiac findings of the Multisystem Inflammatory Syndrome in Children cases that were diagnosed and followed up in our hospital.

MATERIALS AND METHODS

The medical histories, laboratory results, cardiac findings, and treatments of the cases that were diagnosed with Multisystem Inflammatory Syndrome in Children between December 2020 and August 2021 were evaluated retrospectively.

RESULTS

Our study group consisted of 14 males and 12 females whose median age was 3.67 years. Of the 26 patients, 24 had echocardiographic findings and 12 cases had cardiac pathologies that were mostly mild. Among these, mitral valve insufficiency, coronary artery pathology, and pericardial effusion were the most common. Perivascular brightness, aortic and tricuspid insufficiency, systolic dysfunction, and tricuspid thrombosis were less common. The cardiac pathologies of all patients resolved in less than a month following treatment.

CONCLUSION

Although the cardiac pathologies of Multisystem Inflammatory Syndrome in Children cases disappear fairly rapidly, the long-term cardiac effects of this disease are not known clearly. To improve our current understanding of Multisystem Inflammatory Syndrome in Children, more multi-centred studies with long-term follow-up periods should be conducted, and treatment protocols for cases of different severities should be developed to maximise the treatments' efficacy.

Nutraceuticals for Complementary Treatment of Multisystem Inflammatory Syndrome in Children: A Perspective from Their Use in COVID-19

Multisystem inflammatory syndrome in children (MIS-C) has been widely reported in some children diagnosed with SARS-CoV-2. Clinical signs of MIS-C are manifested at 2 to 4 weeks after SARS-CoV-2 infection, where elevated biomarkers of inflammation and cardiac dysfunction are the hallmark of this syndrome when infection or exposure to SARS-CoV-2 has been confirmed. However, after two years of acknowledgment, MIS-C treatment is still under research to reach safety and effectiveness in the acute phase in children. Therefore, in this review, we discuss the potential use of natural compounds with antioxidant and anti-inflammatory effects to reduce collateral damage caused by hyperinflammation in MIS-C pathology for new research in treatment and interventions.

Age-adjusted NT-proBNP could help in the early identification and follow-up of children at risk for severe multisystem inflammatory syndrome associated with COVID-19 (MIS-C)

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) has emerged as a new disease associated with COVID-19 that presents in acute critically ill children with acute cardiovascular dysfunction.

AIM

To determine whether the age-adjusted N-terminal pro-brain natriuretic peptide (NT-proBNP) value (Z-log-NT-proBNP) is associated with severe MIS-C and myocardial dysfunction.

METHODS

A retrospective study was conducted which included children with MIS-C managed at our institution between April 1, 2020, and February 28, 2022. We divided the population into groups depending on severity based on pediatric intensive care unit (PICU) admission. We compared Z-log-NT-proBNP values across these groups and analyzed Z-log-NT-proBNP dynamics during the one-month follow-up.

RESULTS

We included 17 participants [median age 3 (2-9) years] and seven (41%) required PICU admission. All (100%) of these cases presented very high (Z-log > 4) levels of NT-proBNP at the time of admission compared to only 5 (50%) patients with non-severe MIS-C (P = 0.025). NT-proBNP was significantly correlated with high-sensitive Troponin I levels (P = 0.045), Ross modified score (P = 0.003) and left ventricle ejection fraction (P = 0.021).

CONCLUSION

Raised NT-proBNP, specifically very high values (Z-log-NT-proBNP > 4) could help in the early identification of MIS-C patients with myocardial dysfunction requiring inotropic support and PICU admission.

Drugs for the prevention and treatment of COVID-19 and its complications: An update on what we learned in the past 2 years

The COVID-19 Committee of the Lincei Academy has reviewed the scientific evidence supporting the efficacy and safety of existing and new drugs/biologics for the preventing and treating of COVID-19 and its complications. This position paper reports what we have learned in the field in the past 2 years. The focus was on, but not limited to, drugs and neutralizing monoclonal antibodies, anti-SARS-CoV-2 agents, anti-inflammatory and immunomodulatory drugs, complement inhibitors and anticoagulant agents. We also discuss the risks/benefit of using cell therapies on COVID-19 patients. The report summarizes the available evidence, which supports recommendations from health authorities and panels of experts regarding some drugs and biologics, and highlights drugs that are not recommended, or drugs for which there is insufficient evidence to recommend for or against their use. We also address the issue of the safety of drugs used to treat underlying concomitant conditions in COVID-19 patients. The investigators did an enormous amount of work very quickly to understand better the nature and pathophysiology of COVID-19. This expedited the development and repurposing of safe and effective therapeutic interventions, saving an impressive number of lives in the community as well as in hospitals.

MIS-C: A COVID-19-as sociated condition between hypoimmunity and hyperimmunity

Multisystem inflammatory syndrome in children (MIS-C) is a rare, severe complication of COVID-19. A better knowledge of immunological, cellular, and genetic characteristics of MIS-C could help better understand the pathogenesis of the disease and contribute to identifying specific diagnostic biomarkers and develop targeted therapies. We studied 37 MIS-C children at hospital admission and 24 healthy controls analyzing serum cytokines (IFN-α, IFN-β, IFN-γ, IL-6, IL-10, IL-17A, IL-12p70 and TNF), lymphocyte populations by flow cytometry and 386 genes related to autoimmune diseases, autoinflammation and primary immunodeficiencies by NGS. MIS-C patients showed a significant increase of serum IFNγ (despite a significant reduction of activated Th1) and ILs, even if with a great heterogeneity among patients, revealing different pathways involved in MIS-C pathogenesis and suggesting that serum cytokines at admission may help to select the inflammatory pathways to target in each patient. Flow cytometry demonstrated a relevant reduction of T populations while the percentage of B cell was increased in agreement with an autoimmune pathogenesis of MIS-C. Genetic analysis identified variants in 34 genes and 83.3% of patients had at least one gene variant. Among these, 9 were mutated in more patients. Most genes are related to autoimmune diseases like ATM, NCF1, MCM4, FCN3, and DOCK8 or to autoinflammatory diseases associated to the release of IFNγ like PRF1, NOD2, and MEF. Thus, an incomplete clearance of the Sars-CoV2 during the acute phase may induce tissue damage and self-antigen exposure and genetic variants can predispose to hyper-reactive immune dysregulation events of MIS-C-syndrome. Type II IFN activation and cytokine responses (mainly IL-6 and IL-10) may cause a cytokine storm in some patients with a more severe acute phase of the disease, lymphopenia and multisystemic organ involvement. The timely identification of such patients with an immunocytometric panel might be critical for targeted therapeutic management.

A machine-learning algorithm for diagnosis of multisystem inflammatory syndrome in children and Kawasaki disease in the USA: a retrospective model development and validation study

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a novel disease that was identified during the COVID-19 pandemic and is characterised by systemic inflammation following SARS-CoV-2 infection. Early detection of MIS-C is a challenge given its clinical similarities to Kawasaki disease and other acute febrile childhood illnesses. We aimed to develop and validate an artificial intelligence algorithm that can distinguish among MIS-C, Kawasaki disease, and other similar febrile illnesses and aid in the diagnosis of patients in the emergency department and acute care setting.

METHODS

In this retrospective model development and validation study, we developed a deep-learning algorithm called KIDMATCH (Kawasaki Disease vs Multisystem Inflammatory Syndrome in Children) using patient age, the five classic clinical Kawasaki disease signs, and 17 laboratory measurements. All features were prospectively collected at the time of initial evaluation from patients diagnosed with Kawasaki disease or other febrile illness between Jan 1, 2009, and Dec 31, 2019, at Rady Children's Hospital in San Diego (CA, USA). For patients with MIS-C, the same data were collected from patients between May 7, 2020, and July 20, 2021, at Rady Children's Hospital, Connecticut Children's Medical Center in Hartford (CT, USA), and Children's Hospital Los Angeles (CA, USA). We trained a two-stage model consisting of feedforward neural networks to distinguish between patients with MIS-C and those without and then those with Kawasaki disease and other febrile illnesses. After internally validating the algorithm using stratified tenfold cross-validation, we incorporated a conformal prediction framework to tag patients with erroneous data or distribution shifts. We finally externally validated KIDMATCH on patients with MIS-C enrolled between April 22, 2020, and July 21, 2021, from Boston Children's Hospital (MA, USA), Children's National Hospital (Washington, DC, USA), and the CHARMS Study Group consortium of 14 US hospitals.

FINDINGS

1517 patients diagnosed at Rady Children's Hospital between Jan 1, 2009, and June 7, 2021, with MIS-C (n=69), Kawasaki disease (n=775), or other febrile illnesses (n=673) were identified for internal validation, with an additional 16 patients with MIS-C included from Connecticut Children's Medical Center and 50 from Children's Hospital Los Angeles between May 7, 2020, and July 20, 2021. KIDMATCH achieved a median area under the receiver operating characteristic curve during internal validation of 98·8% (IQR 98·0-99·3) in the first stage and 96·0% (95·6-97·2) in the second stage. We externally validated KIDMATCH on 175 patients with MIS-C from Boston Children's Hospital (n=50), Children's National Hospital (n=42), and the CHARMS Study Group consortium of 14 US hospitals (n=83). External validation of KIDMATCH on patients with MIS-C correctly classified 76 of 81 patients (94% accuracy, two rejected by conformal prediction) from 14 hospitals in the CHARMS Study Group consortium, 47 of 49 patients (96% accuracy, one rejected by conformal prediction) from Boston Children's Hospital, and 36 of 40 patients (90% accuracy, two rejected by conformal prediction) from Children's National Hospital.

INTERPRETATION

KIDMATCH has the potential to aid front-line clinicians to distinguish between MIS-C, Kawasaki disease, and other similar febrile illnesses to allow prompt treatment and prevent severe complications.

FUNDING

US Eunice Kennedy Shriver National Institute of Child Health and Human Development, US National Heart, Lung, and Blood Institute, US Patient-Centered Outcomes Research Institute, US National Library of Medicine, the McCance Foundation, and the Gordon and Marilyn Macklin Foundation.

Allergic diseases and immunodeficiencies in children, lessons learnt from COVID-19 pandemic by 2022: A statement from the EAACI-section on pediatrics

By the April 12, 2022, the COVID-19 pandemic had resulted in over half a billion people being infected worldwide. There have been 6.1 million deaths directly due to the infection, but the pandemic has had many more short- and long-term pervasive effects on the physical and mental health of the population. Allergic diseases are among the most prevalent noncommunicable chronic diseases in the pediatric population, and health-care professionals and researchers were seeking answers since the beginning of pandemic. Children are at lower risk of developing severe COVID-19 or dying from infection. Allergic diseases are not associated with a higher COVID-19 severity and mortality, apart from severe/poorly controlled asthma. The pandemic disrupted routine health care, but many mitigation strategies, including but not limited to telemedicine, were successfully implemented to continue delivery of high-standard care. Although children faced a multitude of pandemic-related issues, allergic conditions were effectively treated remotely while reduction in air pollution and lack of contact with outdoor allergens resulted in improvement, particularly respiratory allergies. There is no evidence to recommend substantial changes to usual management modalities of allergic conditions in children, including allergen immunotherapy and use of biologicals. Allergic children are not at greater risk of multisystem inflammatory syndrome development, but some associations with Long COVID were reported, although the data are limited, and further research is needed. This statement of the EAACI Section on Pediatrics provides recommendations based on the lessons learnt from the pandemic, as available evidence.

Factors Associated with Pulse Methylprednisolone Treatment Failure in COVID-19-Related Multisystem Inflammatory Syndrome in Children (MIS-C)

Objective This article determines the occurrence and variables associated with pulse methylprednisolone treatment failure in children with coronavirus disease 2019 (COVID-19)-related multisystem inflammatory syndrome in children (MIS-C).

Methods This prospective observational study was undertaken at a tertiary care teaching hospital in Kerala, India. Children admitted with COVID-19-related MIS-C who were treated with pulse methylprednisolone as first-line therapy were included in the study. Depending on the response to the treatment, they were divided into two groups. The clinical, laboratory parameters, and follow-up findings at 3 months were compared between the two groups

Results Seventy-six patients were admitted with MIS-C during the study period. Sixty received pulse methylprednisolone as the first-line therapy. Of the 60 patients who received pulse methylprednisolone, 50 responded to treatment, while 10 required repeat immunomodulation. Need for noninvasive or invasive ventilation (relative risk [RR]: 13.14, 95% confidence interval [CI]: 3.147–54.88), six or more organ involvement (RR: 4.667, 95% CI: 1.349–16.149), thrombocytopenia (RR: 6.43, 95% CI: 0.87–47.6, p 0.003), and abnormal chest X-ray findings at admission (RR: 4.5, 95% CI: 1.46–13.8), were found to be associated with increased risk of treatment failure with pulse methylprednisolone therapy. Note that 88% of patients with coronary artery involvement showed resolution at 3-month follow-up.

Conclusion More than 80% of children with MIS-C can be treated successfully with corticosteroids. The need for ventilator support, abnormal chest X-ray findings, and thrombocytopenia at admission were found to be factors associated with pulse methylprednisolone treatment failure.

Severe Acute Respiratory Syndrome Coronavirus 2 Vaccination in Children with a History of Multisystem Inflammatory Syndrome in Children: An International Survey

The optimal severe acute respiratory syndrome coronavirus 2 vaccine strategy for patients with a history of multisystem inflammatory syndrome in children (MIS-C) is unclear. We performed an international survey (32 countries) and found substantial variations in vaccine policies. Respondents did not report relapses of MIS-C or other severe inflammatory side effects after severe acute respiratory syndrome coronavirus 2 vaccination in 273 patients with a history of MIS-C.

Multisystem inflammatory syndrome in children (MIS-C) and neonates (MIS-N) associated with COVID-19: optimizing definition and management

During the SARS-CoV-2-associated infection (COVID-19), pandemic initial reports suggested relative sparing of children inversely related to their age. Children and neonates have a decreased incidence of SARS-CoV-2 infection, and if infected they manifested a less severe phenotype, in part due to enhanced innate immune response. However, a multisystem inflammatory syndrome in children (MIS-C) or paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 emerged involving coronary artery aneurysms, cardiac dysfunction, and multiorgan inflammatory manifestations. MIS-C has many similarities to Kawasaki disease and other inflammatory conditions and may fit within a spectrum of inflammatory conditions based on immunological results. More recently neonates born to mothers with SARS-CoV-2 infection during pregnancy demonstrated evidence of a multisystem inflammatory syndrome with raised inflammatory markers and multiorgan, especially cardiac dysfunction that has been described as multisystem inflammatory syndrome in neonates (MIS-N). However, there is a variation in definitions and management algorithms for MIS-C and MIS-N. Further understanding of baseline immunological responses to allow stratification of patient groups and accurate diagnosis will aid prognostication, and inform optimal immunomodulatory therapies. IMPACT: Multisystem inflammatory system in children and neonates (MIS-C and MIS-N) post COVID require an internationally recognized consensus definition and international datasets to improve management and plan future clinical trials. This review incorporates the latest review of pathophysiology, clinical information, and management of MIS-C and MIS-N. Further understanding of the pathophysiology of MIS-C and MIS-N will allow future targeted therapies to prevent and limit clinical sequelae.