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

Kawasaki Disease Before and During the COVID-19 Pandemic: A Nationwide Population-based Study in the United States

BACKGROUND

A decrease in the incidence of Kawasaki disease during the COVID-19 pandemic has been reported globally. Yet, previous US studies utilized patient populations of limited size and geographic scope, leaving a knowledge gap regarding the national trend. Employing a large sample size will increase the generalizability of the results and allow for more detailed analyses.

METHODS

The observational study using the 2016-2020 National (Nationwide) Inpatient Sample examined changes in the Kawasaki disease hospitalization rate in pediatric patients during the COVID-19 pandemic. Sensitivity analyses examined hospitalizations between October and December each year, as the code for multisystem inflammatory syndrome in children was implemented in October 2020.

RESULTS

In total, 24,505 hospitalizations with Kawasaki disease diagnoses were examined. Hospitalization rates were 65.1 and 53.8 per 1,000,000 pediatric population during the prepandemic and pandemic periods, respectively. Sensitivity analyses showed an overall decrease of 36.1%, with larger decreases for patients 1-4 years old (49.6%), males (40.0%), Asians or Pacific Islanders (57.9%) and patients in the South (47.5%), compared with their counterparts. Associations of the pandemic period with longer lengths of stay and higher daily costs were detected (adjusted mean ratio 1.11; P < 0.01 for length of stay, and adjusted mean ratio 1.33, P < 0.01 for costs).

CONCLUSIONS

A decrease in the incidence of Kawasaki disease during the COVID-19 pandemic was observed nationwide in the United States. Contrary to a report from Japan, we did not observe a relationship between population density and a decrease in Kawasaki disease hospitalization. More detailed analyses in targeted geographical areas may provide further insights.

Clinical and Laboratory Characteristics of Kawasaki Disease and COVID-19-Related Multisystem Inflammatory Syndrome in Children

Geographical and racial factors constitute important distinctions between Kawasaki disease (KD) and multisystem inflammatory syndrome in children (MIS-C), but no study has been conducted in Vietnam. Forty-one children with KD from January 2018 to July 2020 and 42 with KD/MIS-C from August 2020 to December 2022 were included in this study. Of the patients, 52.3% were aged between 12 and 35 months. Only two were aged over 5 years, and both were belong to the KD/MIS-C group. A 59.5% of the patients were male. Apart from fever, all symptoms tended to be more frequent in patients with KD/MIS-C. The prevalence of diffuse skin rash, hand and foot edema or erythema and gastrointestinal signs was significantly higher in patients hospitalized with KD/MIS-C. There was no significant difference in laboratory findings between the two groups. Coronary artery dilation was more frequently observed in patients with KD/MIS-C compared to those with KD (40.5% vs. 14.6%, P = 0.009).

[Kawasaki disease and multisystem inflammatory syndrome in children. Differences, and similarities in a pediatric center in Mexico]

OBJECTIVE

To evaluate the differences and similarities in clinical picture, laboratory findings and outcomes between children's with Kawasaki Disease (KD) versus multisystem inflammatory syndrome (MIS-C).

METHODS

We conducted a retrospective, comparative study from children with Kawasaki Disease (KD) hospi-talized in Sinaloa Pediatric Hospital from January 1, 2004, to March 31, 2020, and patients with multisystem inflammatory syndrome (MIS-C) according with World Health Organization (WHO) case definition criteria be-tween May 1, 2020 and May 31, 2021. Demographic characteristics, epidemiological data, clinical features, laboratory findings, type of treatment and clinical outcomes were compared among both groups.

RESULTS

Eighty-one patients were included (62 patients with KD and 19 with MIS-C). several clinical and lab-oratory differences were found among these two entities. Median age was lower in KD vs. MIS-C (25 vs 79 months). Those finding more frequent in KD were male gender (64.5 vs. 47.4%), Mucocutaneous features (93.5 vs. 63.2%): Oral changes (83.9 vs. 63.2%) and extremity changes (77.4 vs. 57.9%); complete form of KD was (75.8 vs. 47.4%), Coronary artery aneurysm (16.1 vs. 11.8%). Secondly, findings that were more frequent in MIS-C than KD were Gastrointestinal involvement (89.4 vs. 9.6%), shock (57.9 vs. 3.2%), neurological symp-toms (63.1 vs. 11.2%), kidney involvement (52.6 vs. 16.1%), heart disease in general (52.9% vs 29%): Myocardial dysfunction (23.5 vs. 11.3%) and pericardial effusion (17.6 vs. 2.9%). Lymphocyte count (2.07 + 2.03 vs. 4.28 + 3.01/mm3), platelet count (197.89 + 187.51 vs. 420.37 + 200.08/mm3); serum albumin (2.29 + 0.65 vs. 3.33 + 0.06g/dL), and CPR (21.4 + 11.23 vs. 14.26 + 12.37 mg/dL). KD vs. MIS-C types of Treatment: IVIG (96.8 vs. 94.7%), systemic steroids (4.82 vs. 94.7%), IVIG resistance (19.4 vs. 15.8). Finally, mortality in KD was 0% and 5.3% in MIS-C.

CONCLUSIONS

Similarities were found in both groups such as fever, rash, and conjunctivitis. Nevertheless, signifi-cant differences such as severity of clinical presentation with multi-organ involvement and worst inflammato-ry response were found more frequently in MIS-C group than KD group, requiring more fluid replacement, use of inotropic agents and higher steroids dosages. Also, mortality rate was higher in patients with MIS-C thanpatients with KD. Similar results have been observed in other studies where both disorders were compared.

Multisystem inflammatory syndrome in adults: Comparison with other inflammatory conditions during the Covid-19 pandemic

BACKGROUND

Multisystem inflammatory syndrome in adults (MIS-A) is an increasingly recognized complication of Covid-19. We assessed risk factors, clinical characteristics, and outcomes of patients with MIS-A compared with other inflammatory conditions.

METHODS

We analyzed a cohort of patients ≥21 years hospitalized with MIS-A in Quebec, Canada between February 2020 and March 2021. We included comparison groups that share symptomatology or pathophysiology with MIS-A, including Kawasaki disease, toxic shock syndrome, and other Covid-19 complications. We examined characteristics of men and women at admission, and identified preexisting factors associated with MIS-A through odds ratios (OR) and 95% confidence intervals (CI) from adjusted logistic regression models.

RESULTS

Among 22,251 patients in this study, 52 had MIS-A, 90 Kawasaki disease, 500 toxic shock syndrome, and 21,609 other Covid-19 complications. MIS-A was associated with an elevated risk of respiratory failure compared with Kawasaki disease (OR 7.22, 95% CI 1.26-41.24), toxic shock syndrome (OR 4.41, 95% CI 1.73-11.23), and other Covid-19 complications (OR 3.03, 95% CI 1.67-5.50). Patients with MIS-A had a greater risk of cardiac involvement, renal failure, and mortality. The data pointed towards sex-specific differences in presentation, with more respiratory involvement in women and cardiac involvement in men compared with patients that had other Covid-19 complications. Except for allergic disorders and cancer, prior medical risk factors were not associated with a greater likelihood of MIS-A.

CONCLUSIONS

Patients with MIS-A have an elevated risk of mortality compared with other inflammatory conditions, with women having a predominance of respiratory complications and men cardiovascular complications.

Coronavirus disease 2019-related Kawasaki syndrome: a case report

BACKGROUND

Coronavirus disease 2019 has changed the pattern of some diseases in the world, especially in pediatrics. Despite data suggesting that the pediatric population is less affected by coronavirus disease-19 infection, new concerns have been raised owing to reported cases with hyperinflammatory conditions such as Kawasaki disease.

CASE PRESENTATION

We report herein the case of a pediatric patient diagnosed and treated for classic Kawasaki disease in the setting of confirmed coronavirus disease 2019 infection. She was an 8-year-old, previously healthy, and fully immunized Iranian girl who initially presented to the pediatric emergency department with 5 days of intermittent fever, followed by abdominal pain, nausea, and vomiting. She was admitted for fever and abdominal pain to the surgery service of Akbar Hospital with suspected appendicitis.

CONCLUSIONS

This case report may serve as a useful reference to other clinicians caring for pediatric patients affected by coronavirus disease 2019 infection. Standard therapeutic interventions for Kawasaki disease must be performed to prevent critical coronary aneurysm-related complications in the coronavirus disease 2019 era.

Distinguishing immune activation and inflammatory signatures of multisystem inflammatory syndrome in children (MIS-C) versus hemophagocytic lymphohistiocytosis (HLH)

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a potentially life-threatening sequela of severe acute respiratory syndrome coronavirus 2 infection characterized by hyperinflammation and multiorgan dysfunction. Although hyperinflammation is a prominent manifestation of MIS-C, there is limited understanding of how the inflammatory state of MIS-C differs from that of well-characterized hyperinflammatory syndromes such as hemophagocytic lymphohistiocytosis (HLH).

OBJECTIVES

We sought to compare the qualitative and quantitative inflammatory profile differences between patients with MIS-C, coronavirus disease 2019, and HLH.

METHODS

Clinical data abstraction from patient charts, T-cell immunophenotyping, and multiplex cytokine and chemokine profiling were performed for patients with MIS-C, patients with coronavirus disease 2019, and patients with HLH.

RESULTS

We found that both patients with MIS-C and patients with HLH showed robust T-cell activation, markers of senescence, and exhaustion along with elevated TH1 and proinflammatory cytokines such as IFN-γ, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10. In comparison, the amplitude of T-cell activation and the levels of cytokines/chemokines were higher in patients with HLH when compared with patients with MIS-C. Distinguishing inflammatory features of MIS-C included elevation in TH2 inflammatory cytokines such as IL-4 and IL-13 and cytokine mediators of angiogenesis, vascular injury, and tissue repair such as vascular endothelial growth factor A and platelet-derived growth factor. Immune activation and hypercytokinemia in MIS-C resolved at follow-up. In addition, when these immune parameters were correlated with clinical parameters, CD8+ T-cell activation correlated with cardiac dysfunction parameters such as B-type natriuretic peptide and troponin and inversely correlated with platelet count.

CONCLUSIONS

Overall, this study characterizes unique and overlapping immunologic features that help to define the hyperinflammation associated with MIS-C versus HLH.

Global Research Trends in Pediatric COVID-19: A Bibliometric Analysis

Background

Coronavirus disease 2019 (COVID-19) emerged in 2019 and has since caused a global pandemic. Since its emergence, COVID-19 has hugely impacted healthcare, including pediatrics. This study aimed to explore the current status and hotspots of pediatric COVID-19 research using bibliometric analysis.

Methods

The Institute for Scientific Information Web of Science core collection database was searched for articles on pediatric COVID-19 to identify original articles that met the criteria. The retrieval period ranged from the creation of the database to September 20, 2021. A total of 3,561 original articles written in English were selected to obtain data, such as author names, titles, source publications, number of citations, author affiliations, and countries where the studies were conducted. Microsoft Excel (Microsoft, Redmond, WA) was used to create charts related to countries, authors, and institutions. VOSviewer (Center for Science and Technology Studies, Leiden, The Netherlands) was used to create visual network diagrams of keyword, author, and country co-occurrence.

Results

We screened 3,561 publications with a total citation frequency of 30,528. The United States had the most published articles (1188 articles) and contributed the most with author co-occurrences. The author with the most published articles was Villani from the University of Padua, Italy. He also contributed the most co-authored articles. The most productive institution was Huazhong University of Science and Technology in China. The institution with the most frequently cited published articles was Shanghai Jiao Tong University in China. The United States cooperated most with other countries. Research hotspots were divided into two clusters: social research and clinical research. Besides COVID-19 and children, the most frequent keywords were pandemic (251 times), mental health (187 times), health (172 times), impact (148 times), and multisystem inflammatory syndrome in children (MIS-C) (144 times).

Conclusion

Pediatric COVID-19 has attracted considerable attention worldwide, leading to a considerable number of articles published over the past 2 years. The United States, China, and Italy have leading roles in pediatric COVID-19 research. The new research hotspot is gradually shifting from COVID-19 and its related clinical studies to studies of its psychological and social impacts on children.

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

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

Kawasaki disease in Malaysia: Biochemical profile, characterization, diagnosis and treatment

INTRODUCTION

Kawasaki disease (KD) is an acute idiopathic systemic vasculitis with a self- limiting course that predominantly affects children under 5 years old, particularly in the East Asian countries. Nevertheless, to date, the data on KD in Malaysia are limited. This study aimed to evaluate the epidemiology, clinical features, treatment, and outcomes of KD among the pediatric patients admitted to Hospital Canselor Tunku Muhriz (HCTM), Kuala Lumpur, Malaysia.

METHOD

A retrospective cohort study of 66,500 pediatric patients presented at HCTM from the year 2004 to 2021 was conducted.

RESULTS

62 KD cases out of 66,500 pediatric admissions were reported, with a male-to-female ratio of 1.58 to 1. Majority of KD patients (95.0%) were younger than 5 years old. Prior infection was reported in 5 KD patients (8.1%). Apart from the classical features, manifestations of various organ systems including cardiovascular (16.1%), gastrointestinal (43.5%), neurological (1.61%), musculoskeletal (1.61%), and genitourinary (17.7%) systems were observed. There was a significant association between sterile pyuria and coronary artery aneurysm (CAA) (p < 0.05). Interestingly, abnormal liver parameters (p < 0.05) and incomplete KD (p < 0.05) were significantly related to IVIG resistance.

DISCUSSION

The presence of family history, immunological disorder, and previous infection in our KD patients suggested that there is a possibility of genetic, immunological, and infectious roles in the pathophysiology of KD. IVIG resistance is more likely to occur in KD patients with hepatic dysfunction or incomplete KD presentation. These findings highlighted the significant contribution of laboratory parameters to the prognosis of KD, prompting more in-depth research on the KD scoring systems and their relevance in this country.

Pediatric cardiothoracic vasculitis: multimodality imaging review

The pediatric vasculitides are a relatively uncommon and heterogeneous group of disorders characterized by vessel inflammation, often with cardiothoracic involvement. Diagnosis and monitoring are often clinically challenging because of the nonspecific symptoms and laboratory markers. Thus, imaging has assumed increasing importance for early detection of disease activity, extent and complications as well as long-term monitoring pre- and post-treatment. Herein, we review the major pediatric vasculitides with frequent chest manifestations, including Takayasu arteritis, Kawasaki disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, microscopic polyangiitis, Behçet disease and potential mimics. We highlight key clinical features and management considerations, emphasizing the central role of imaging.

Case Report: Successful Treatment of a Child With COVID-19 Reinfection-Induced Fulminant Myocarditis by Cytokine-Adsorbing oXiris® Hemofilter Continuous Veno-Venous Hemofiltration and Extracorporeal Membrane Oxygenation

BACKGROUND

Indirect cardiomyocyte damage-related hyperinflammatory response is one of the key mechanisms in COVID-19-induced fulminant myocarditis. In addition to the clinical benefit of using cytokines absorption hemofiltration, the effectiveness of instituting veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support for cardiac compromise has been reported. However, current literature enunciates a paucity of available data on the effectiveness of these novel modalities.

CASE PRESENTATION

We reported a 9-year-old boy with recurrent COVID-19 infection-causing fulminant myocarditis, who was treated successfully by using novel modalities of oXiris ^® hemofilter continuous venovenous hemofiltration (CVVH) and VA-ECMO. The patient made a full recovery without any sequelae.

CONCLUSION

We conclude that the novel highly-absorptive hemofilter CVVH and VA-ECMO may be effective treatment modalities in managing SARS-CoV-2-induced fulminant myocarditis. Our report highlights the need for further well-designed investigations to confirm this extrapolation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

SYSTEMATIC REVIEW REGISTRATION

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

Infliximab treatment for refractory COVID-19-associated multisystem inflammatory syndrome in a Japanese child

Patients with multisystem inflammatory syndrome in children (MIS-C) can develop clinical features resembling Kawasaki disease (KD). A full picture of MIS-C in East Asia which has higher incidence of KD than other regions remains unclear. We report on a 15-year-old Japanese boy with refractory MIS-C who was successfully treated with infliximab. A Japanese boy who was diagnosed with coronavirus disease 2019 (COVID-19) before a month developed MIS-C with fulfilling six principal symptoms of KD. Laboratory data showed extreme hyperferritinemia (11,404 ng/mL), besides lymphopenia and thrombocytopenia. The patient was refractory to initial therapy with intravenous immunoglobulin (IVIG; 2 g/kg), aspirin, and prednisolone. He was therefore administered a second IVIG (2 g/kg) and infliximab (5 mg/kg) on days 7 and 8 from the onset of fever, respectively, which resulted in an improvement of clinical symptoms. Only four Japanese cases with MIS-C were reported and all of them were responsive to IVIG. The hyperferritinemia in this case was distinctive from previously reported MIS-C cases in Japan and other cohorts and may be associated with refractoriness to IVIG therapy. Marked elevation of circulating ferritin levels is known to be induced by tumor necrosis factor-α, which plays a key role in the pathogenesis of both KD and MIS-C. Thus, for MIS-C patients with hyperferritinemia, early intervention with adjunctive infliximab may induce a more rapid resolution of inflammation and improve outcome. Because MIS-C may be heterogeneous with respect to immunopathology, genetic background, clinical phenotypes and response to therapies, optimized treatment strategies according to immunopathogenesis are required.

Clinical characteristics of Kawasaki disease in adolescents

Objective

Studies focusing on Kawasaki disease (KD) in adolescents are lacking in Southwest China. We systematically summarized the clinical characteristics of KD in adolescents to improve pediatricians’ recognition of this condition.

Methods

The clinical data of patients with adolescent-onset KD in our center were retrospectively analyzed. The patients were divided into Group A (n = 7), whose first hospitalization was at our hospital, and Group B (n = 10), who were transferred from their local hospital or community health center.

Results

Seventeen patients with adolescent-onset KD were identified (constituent ratio of 0.8%). Seven patients had an intermittent fever for >10 days. The incidence of incomplete KD was 52.9%. These patients had a high incidence of other atypical clinical manifestations. Fifteen patients were initially misdiagnosed with other infectious diseases. Although the incidence of typical KD was higher in Group B, the overall misdiagnosis rate at the initial stages was higher and the average fever duration on arrival and before IVIG administration were much longer in Group B than A.

Conclusions

KD in adolescents was frequently misdiagnosed, which might be associated with its atypical, diverse clinical features and pediatricians’ poor recognition. Pediatricians must be aware of the possibility of KD in adolescents.

Unraveling the mechanisms of IVIG immunotherapy in MIS-C

In The Journal of Clinical Investigation, Zhu et al.¹ report that intravenous immunoglobulin (IVIG) targets IL-1β⁺ neutrophils to exert anti-inflammatory effects in multisystem inflammatory syndrome in children (MIS-C), a post-infectious inflammatory condition associated with COVID-19.

The impact of the COVID-19 pandemic on child health

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