Management of COVID-19-associated multisystem inflammatory syndrome in children: A comprehensive literature review

Multisystem inflammatory syndrome drug treatment in countries with different income profiles: a scoping review

Objective: The purpose of this study was to map and describe the studies that have investigated therapeutic alternatives for the management of paediatric multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19. Considering the origin of the studies performed (low-, middle- and high-income countries), a systematic scoping review was conducted with primary studies that reported the use of medications for the treatment of patients with MIS-C. Sources: The searches were performed in MEDLINE, Embase, Lilacs, Epistemonikos, CINAHL, and CENTRAL, in the grey literature (theses and dissertations from CAPES, ProQuest, and PROSPERO) and in clinical trial databases until May 2022. The selection and extraction of studies were performed independently by two reviewers. Summary of the findings: A total of 173 studies were included, most of which were published as case reports or series. No randomized controlled clinical trials (RCTs) were identified. The investigated drugs were immunoglobulins, glucocorticoids, monoclonal antibodies, anticoagulants, and antiplatelet agents. Conclusion: The dosages, when reported, were heterogeneous among the studies. The ethnicity and comorbidity of the participants were poorly reported. Monoclonal antibodies, drugs with higher costs, were mostly described in studies of high-income countries.

Coincidental or mimicking acute appendicitis secondary to MIS-C associated with SARS-CoV-2: A case report

The predominant organic system involved in multisystem inflammatory syndrome in children associated with COVID-19 is the gastrointestinal system, which is observed in almost 90% of patients. Gastrointestinal symptoms can mimic acute appendicitis. There have been a few cases of misdiagnosed multisystem inflammatory syndrome in children associated with SARS-CoV-2 as appendicitis, and a few concomitant cases of a multisystem inflammatory syndrome associated with acute appendicitis during the COVID-19 pandemic. Here, we present the case of an 11-year-old girl who presented to our Intensive Care Unit with a 2-day history of fever, generalized abdominal pain, and vomiting. The clinical findings resulted in a clinical suspicion of acute appendicitis and subsequent surgery. While postoperatively, she became critically ill, and she was diagnosed with the multisystem inflammatory syndrome in children associated with COVID-19. When diagnosing children with acute appendicitis, healthcare professionals, especially pediatricians and surgeons, must pay attention to the multisystem inflammatory syndrome linked to the SARS-CoV-2 infection.

Short-term Outcomes of Corticosteroid Monotherapy in Multisystem Inflammatory Syndrome in Children

IMPORTANCE

Optimal agents and duration of primary treatment for multisystem inflammatory syndrome in children (MIS-C) remain unclear.

OBJECTIVE

To compare short-term patient outcomes based on initial treatment with corticosteroids, intravenous immunoglobulin (IVIG), or both.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included patients in a tertiary-care pediatric hospital system who had MIS-C per the Centers for Disease Control and Prevention case definition during the period March 2020 to February 2021.

EXPOSURES

Immunomodulatory therapy within the first 24 hours (patients in the intensive care unit [ICU]) or 48 hours (non-ICU patients): corticosteroids alone, IVIG alone, and IVIG plus corticosteroids.

MAIN OUTCOMES AND MEASURES

Primary outcome was failure of initial therapy, defined as therapy escalation due to fever or worsening or lack of improvement of laboratory, cardiac, or noncardiac clinical factors after 24 hours (ICU patients) or 48 hours (non-ICU patients) from time of therapy initiation, per clinician assessment. Secondary outcomes included presence of complications, cardiovascular outcomes, fever duration, length of hospital and ICU stays, corticosteroid use duration, and need for readmission.

RESULTS

Among 228 eligible patients, 215 patients were included in the univariate analysis; median age was 8 years, and 135 (62.8%) were boys. There were 69 patients in the corticosteroids group, 31 patients in the IVIG group, and 115 patients in the IVIG plus corticosteroids group. Patients in the corticosteroids group had milder disease at presentation. After propensity score weighting including 179 patients (68 in the corticosteroids group and 111 in the IVIG plus corticosteroids group), rates of initial treatment failure were similar between groups. Among patients whose initial treatment failed, treatment failure in the IVIG plus corticosteroids group was more likely to be based on laboratory parameters (odds ratio [OR], 1.96; 95% CI, 1.07-3.60) and less likely to be based on cardiovascular markers (OR, 0.39; 95% CI, 0.2-0.76), per clinician assessment. Patients in the IVIG plus corticosteroids group had a longer median inpatient stay (6 vs 5 days; P = .001) and longer median corticosteroid course duration (10 vs 5 days; P = .04) compared with the corticosteroids group. Forty-nine patients (71% of 69 in the corticosteroids group) recovered after receiving corticosteroid monotherapy for 10 days or less.

CONCLUSIONS AND RELEVANCE

Corticosteroid monotherapy is a reasonable management option for a subset of patients with MIS-C, particularly those with mild disease.

Cytokine Cascade in Kawasaki Disease Versus Kawasaki-Like Syndrome

Kawasaki disease (KD) is a medium vessel systemic vasculitis that predominantly occurs in children below five years of age. It is an acute febrile condition in which coronary artery aneurysms and myocarditis are the most common cardiovascular complications. It is most often characterized by hypercytoki-nemia. The etiopathogenesis of KD is not fully understood. The present review synthesizes the recent advances in the pathophysiology and treatment options of KD. According to different studies, the genetic, infections and autoimmunity factors play a major role in pathogenesis. Several susceptibility genes (e.g. caspase 3) and cytokines (e.g. IL-2, IL-4, IL-6, IL-10, IFN-γ and TNF-α) have been identified in KD. Patients with high cytokine levels are predisposed to KD shock syndrome. The importance of respiratory viruses in the pathogenesis of the disease is unclear. Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce in children and adults an abnormal systemic inflammatory response. This syndrome shares characteristics with KD. It has been called by many terms like MIS-C (Multisystem Inflammatory Syndrome in Children), PIMS-TS (pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2), hyperinflammatory shock syndrome, cytokine storm (cytokine release syndrome) or simply, Kawasaki-like syndrome. The cytokine’s role in the development of KD or Kawasaki-like syndrome being triggered by COVID-19 is controversial. The presences of the antiendothelial cell autoantibodies (AECAs) together with the newly developed hypothesis of immunothrombosis are considered potential pathogenic mechanisms for KD. In consequence, the diagnosis and treatment of KD and Kawasaki-like syndrome, one of the most common causes of acquired heart disease in developed countries, are challenging without a clearly defined protocol.

Giant Coronary Aneurysm in an Infant with Multisystem Inflammatory Syndrome

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV2), also known as COVID-19, has rapidly spread resulting in a worldwide pandemic. Although COVID-19 infections in children are generally mild and nonfatal, there is increasing recognition of its association with the multisystem inflammatory syndrome in children (MIS-C), leading to serious illness and possible long-term complications. This report describes a 6-month-old Indian infant who presented with a 4-day history of fever with nonspecific signs of viral illness and erythematous rash. Although the initial echocardiogram was normal, subsequent scans showed progressive dilatation of bilateral coronary arteries. Despite the timely intervention, he developed left coronary artery thrombosis, leading to myocardial infarction. His SARS-CoV-2 antibody titers were strongly positive. Through this case, we discuss the management of MIS-C with coronary artery involvement. The long-term outcome of coronary artery aneurysm due to MIS-C remains unknown and close follow-up is important. Further research is pivotal for a better understanding of MIS-C.

Prevalence of paediatric hyperinflammatory conditions in paediatric and adolescent hospitalized COVID-19 patients: a systematic review and meta-analysis

In the milieu of coronavirus disease 2019 (COVID-19), there are increasing reports of paediatric hyperinflammatory conditions (PHICs), including multisystem inflammatory syndrome in children (MIS-C), paediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (PIMS-TS) and Kawasaki disease (KD). Few analyses of PHIC prevalence in paediatric and adolescent hospitalized COVID-19 patients exist. The purpose of this study was to perform a meta-analysis to determine a pooled prevalence estimate of PHICs in paediatric and adolescent hospitalized patients admitted for treatment due to COVID-19. Individual studies were retrieved from PubMed/Medline, EMBASE and Cochrane databases. Relevant prevalence, baseline, treatment and outcome data were extracted using a standardized datasheet. The systematic review and meta-analysis were conducted as per the PRISMA and MOOSE guidelines. Overall, 14 studies with 2202 patients admitted for treatment due to COVID-19, among whom 780 were diagnosed with PHICs, were included. The crude estimate of prevalence was 35.42%, and the pooled estimate of prevalence was 29% (random pooled ES = 0.29; 95% CIs = 0.18-0.42; p < 0.0001; z = 7.45). A sizeable proportion of paediatric and adolescent hospitalized patients admitted for treatment due to COVID-19 are diagnosed with a PHIC warranting a high index of clinical suspicion for PHICs. Further studies are required to validate these findings.

Pediatric Inflammatory Multisystem Syndrome or Multisystem Inflammatory Syndrome in Children: A New Thread in Pandemic Era

After the perturbing effects of the COVID-19 Pandemic, we observed intense public health efforts in a global-scale to prevent, control, and treat the SARS-CoV-2. Hundreds of clinical center researched for adequate treatments, other were devoted to the development the COVID-19 vaccines and other studied the nature and the effects of this mutant coronavirus SARS-CoV-2. As time goes by, the pediatric inflammatory multisystem syndrome has been recently defined and associated the COVID-19 past infection and is now considered a shot to middle-term complication of COVID-19. In this paper, we review the actual concepts of PIMS in children, the epidemiology, the clinical presentation, and evolution, the recommended laboratory and other testing. The recommended specialties interconsultation for hospitalized patients and a full discussion on the appropriate treatment of these patients. We include the Latin-American experience with PIMS and a final discussion on the outcome of this disease.

Osteopontin as a biomarker for COVID-19 severity and multisystem inflammatory syndrome in children: A pilot study

This study sought to evaluate the candidacy of plasma osteopontin (OPN) as a biomarker of COVID-19 severity and multisystem inflammatory condition in children (MIS-C) in children. A retrospective analysis of 26 children (0-21 years of age) admitted to Children's Healthcare of Atlanta with a diagnosis of COVID-19 between March 17 and May 26, 2020 was undertaken. The patients were classified into three categories based on COVID-19 severity levels: asymptomatic or minimally symptomatic (control population, admitted for other non-COVID-19 conditions), mild/moderate, and severe COVID-19. A fourth category of children met the Centers for Disease Control and Prevention's case definition for MIS-C. Residual blood samples were analyzed for OPN, a marker of inflammation using commercial ELISA kits (R&D), and results were correlated with clinical data. This study demonstrates that OPN levels are significantly elevated in children hospitalized with moderate and severe COVID-19 and MIS-C compared to OPN levels in mild/asymptomatic children. Further, OPN differentiated among clinical levels of severity in COVID-19, while other inflammatory markers including maximum erythrocyte sedimentation rate, C-reactive protein and ferritin, minimum lymphocyte and platelet counts, soluble interleukin-2R, and interleukin-6 did not. We conclude OPN is a potential biomarker of COVID-19 severity and MIS-C in children that may have future clinical utility. The specificity and positive predictive value of this marker for COVID-19 and MIS-C are areas for future larger prospective research studies.

Ocular and Systemic Manifestations in Paediatric Multisystem Inflammatory Syndrome Associated with COVID-19

This study aimed to achieve a better understanding of the epidemiological and clinical characteristics of multisystem inflammatory syndrome in children (MIS-C) following coronavirus disease 2019 (COVID-19). We searched PubMed and Embase between December 2019 and March 2021 and included only peer-reviewed clinical studies or case series. The proportions of patients who had conjunctivitis, systemic symptoms/signs (s/s), Kawasaki disease (KD), and exposure history to suspected/confirmed COVID-19 cases were obtained. Moreover, positive rates of the nasopharyngeal real-time reverse transcriptase polymerase chain reaction (RT-PCR) and serum antibody for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were recorded. Overall, 32 studies with 1458 patients were included in the pooled analysis. Around half of the patients had conjunctivitis. The five most common systemic manifestations were fever (96.4%), gastrointestinal s/s (76.7%), shock (61.5%), rash (57.1%), and neurological s/s (36.8%). Almost one-third presented complete KD and about half had exposure history to COVID-19 cases. The positivity of the serology (82.2%) was higher than that of the nasopharyngeal RT-PCR (37.0%). MIS-C associated with COVID-19 leads to several features similar to KD. Epidemiological and laboratory findings suggest that post-infective immune dysregulation may play a predominant role. Further studies are crucial to elucidate the underlying pathogenesis.