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

Asymptomatic SARS-COV2 Infection or COVID-19 vaccination effect for severe multisystem inflammatory syndrome in a 6-year-old girl: case report and review of the literature

BACKGROUND

Multisystem Inflammatory Syndrome in Children (MIS-C) is a rare complication, which develops within 3-6 weeks after SARS-CoV2 infection. The coronavirus disease 2019 (COVID-19) vaccine was firstly introduced in adults and adolescents and later in patients aged 5-11 years old. Although a reduced incidence of MIS-C and with less severe symptoms has been reported in vaccinated adolescents, there is little knowledge in children younger than 12 years of age. In addition, it is not understood whether MIS-C in vaccinated patients can be triggered by Covid19 vaccination or be secondary to a recent asymptomatic Sars-Cov2 infection.

CASE PRESENTATION

We describe the case of a Caucasian 6-year-old girl, one month after double COVID-19 vaccination, who presented fever, acute abdominal pain, rash, pharyngotonsillitis, cheilitis, cervical lymphadenopathy without a prior detected Sars-Cov2 infection. She also had lymphopenia, increase in inflammatory markers, cardiac and pulmonary involvement. Therefore, we dosed both anti Sars-Cov2 Spike and Nucleocapsid antibodies, which were positive and allowed us to confirm the diagnosis of MIS-C. We promptly administered intravenous immunoglobulins and methylprednisone, resulting in the initial regression of fever. During the hospitalization, the child also developed pancreatitis and severe neurological involvement, including irritability, drowsiness, distal tremor, dyskinesia and buccal asymmetry with complete resolution after 2 months. After 3 months from the onset of the symptoms, she reported a transient loss of hair compatible with telogen effluvium. After 12 months of follow-up, she did not show any symptomatic sequelae.

CONCLUSIONS

This case raises the question of whether COVID-19 vaccination may be involved in the pathogenesis of MIS-C in children between the ages of 5 and 11 years old.

Clinical and Laboratory Parameters Associated with PICU Admission in Children with Multisystem Inflammatory Syndrome Associated with COVID-19 (MIS-C)

Background/Objectives: Multisystem Inflammatory Syndrome in children (MIS-C) is a rare but severe post-infectious complication of COVID-19 that often requires admission to the Pediatric Intensive Care Unit (PICU). The present study aimed to compare the demographic, clinical, and laboratory characteristics of children diagnosed with MIS-C who were admitted to the PICU and those who did not require PICU admission. Methods: Children diagnosed with MIS-C from September 2020 to April 2023 were included in this case-control study. Demographic, clinical, and laboratory data were collected from medical records. Results: Fifty children with MIS-C were included in the study [median (IQR) age: 7.5 (4.3, 11.4) years, 28/50 (56%) males]. Twenty-two (22/50, 44%) children required admission to the PICU. In the multivariate regression analysis, hepatic (OR: 12.89, 95%CI: 1.35-123.41, p-value = 0.03) and cardiological involvement (OR: 34.55, 95%CI: 2.2-541.91, p-value = 0.01) were significantly associated with hospitalization at the PICU. Regarding the laboratory and imaging parameters during the first 48 h from admission, D-dimer levels higher than 4 μg/mL and decreased Left Ventricular Ejection Fraction (LVEF) were associated with an increased risk of PICU admission (OR: 7.95, 95%CI: 1.48-42.78, p-value = 0.02 and OR = 1.28, 95%CI: 1.07-1.53, p-value = 0.01). Children who were admitted to the PICU were more likely to develop complications during their hospitalization (10/22, 45.5% vs. 3/28, 10.7%, p-value = 0.005) and were hospitalized for more days than children in the pediatric ward (median length of stay (IQR): 20 (15, 28) days vs. 8.5 (6, 14) days, p-value < 0.001). Conclusions: The findings of this study indicate that cardiovascular and hepatic involvement and increased D-dimer levels in children with MIS-C might be associated with admission to the PICU.

Dynamics of multisystem inflammatory syndrome in children associated to COVID-19 in Chile: Epidemiologic trends during pandemic, before and after children vaccination

BACKGROUND

Multisystem inflammatory syndrome associated to Covid-19 (MIS-C) is one of the most severe outcomes of SARS-CoV-2 in children. Covid-19 vaccines were successfully implemented in Chile for the pediatric population since 2021, using both mRNA and inactivated platforms. Effectiveness against MIS-C has been reported for mRNA vaccines. The aim of this study was to describe the epidemiologic trend of MIS-C in Chile during Covid-19 pandemic, both before and after the availability of vaccination for children.

MATERIALS AND METHODS

Analytic study of MIS-C cases from April 2020 to December 2022. Epidemiological data, SARS-CoV-2 variants and vaccination uptake information were obtained from the Epidemiology Department-Ministry of Health, Institute of Public Health and the National Immunization Program, respectively.

RESULTS

496 cases of MIS-C were reported, 58 % males. Median age was 5 years and most frequent age-cohorts were 6-11 and 0-2 years old with a 33 % each. After the introduction of the Covid-19 vaccine, most cases occurred in children aged 0-2 years. Incidence rates were 3.8, 5.4 and 1.7 per 100,000 inhabitants in 2020, 2021 and 2022, respectively. 97 % of cases (481) occurred in unvaccinated subjects. On those previously vaccinated (15), all but one case occurred in children receiving the inactivated vaccine. No association among circulating variants and incidence was observed. Incidence rate reduction (IRR) comparison between 2020 and 2021-2022 periods was 0.72 (CI 95 % 0.65-0.81, p < 0.05) overall; 0.86 for 0-2 years (CI 95 %:0.71-1; p = 0.12); 0.88 for 3-5 years (CI 95 %:0.69-1.11; p = 0.28); 0.61 for 6-11 years (CI 95 %: 0.50-0.75; p < 0.05); and 0.64 for 12-17 years (CI 95 %:0.47-0.89; p < 0.05), consistent with vaccination uptake during the studied period: 63 % for 3-5 years, 91 % for 6-11 years, and 99 % for 12-17 years.

CONCLUSIONS

A decline of MIS-C incidence and a shift to younger, unvaccinated population overtime was observed. IRR decreased in age-cohorts which achieved high vaccination rates.

Complications of Multisystem Inflammatory Syndrome Associated with SARS-CoV-2 Infection-Many Facets of One Disease-A Literature Review Based on a Case Report

Multisystem inflammatory syndrome in children (MIS-C) is a disease that made its mark in the early days of the COVID-19 pandemic due to the diverse course and symptoms affecting multiple body systems. It is a condition that develops in pediatric patients about 2-6 weeks after contact with a person infected with the SARS-CoV-2 virus. In many instances, MIS-C has caused multiple organ failure, with particularly severe complications involving the cardiovascular system and manifesting as hypotension, various cardiac arrhythmias, myocarditis or coronary artery lesions resembling those seen in Kawasaki disease. Currently, the incidence of MIS-C is about 1-3 per 1000 children, with a decreasing trend in recent years due to the introduction of immunization against the SARS-CoV-2 virus for children as young as 6 months. In our paper, we present the case of a patient with a severe course of MIS-C with numerous cardiovascular and neurological complications, in whom the symptoms of the disease were managed by administering biological treatment. We also present a review of the literature on the subject, which shows how many different facets this disease can have and that physicians still need to remain alert, as there are cases of severe MIS-C, especially in unvaccinated patients.

An epidemiological study of multisystem inflammatory syndrome in children (MIS-C) and young adults among COVID-19-positive patients - data from National Inpatient Sample database

During the pandemic of COVID-19, a novel atypical set of clinical findings was seen among several children with recent or current exposure to the virus. It was termed the "multisystem inflammatory syndrome in children" (MIS-C). Our study used the 2021 National Inpatient Sample to study the associations of sex, race, and age with the incidence of MIS-C among COVID-19-positive children. Out of 69,440 COVID-19-positive children, 2,790 (4.0%) reported MIS-C. The incidence of MIS-C was highest among those aged 8 years old (17,130 MIS-C cases per 100,000 COVID-19 patients), Asian or Pacific Islanders (API) (5,346 MIS-C per 100,000 COVID-19 cases), and males (4,734 cases per 100,000 COVID-19 cases). Furthermore, 7.9% of MIS-C cases met the classification of Kawasaki disease.

Evolution of Cardiovascular Findings in Multisystem Inflammatory Syndrome in Children (MIS-C) Across COVID-19 Variants: Common Trends and Unusual Presentations

Multisystem inflammatory syndrome in children (MIS-C) is a rare condition following COVID-19 infection. Cardiac involvement is common and includes left ventricular systolic dysfunction, cardiac marker elevation, electrocardiogram (ECG) changes, and coronary artery dilation. This single-center retrospective cohort study compares cardiovascular disease between three major SARS-CoV-2 variants and describes the evolution of findings in medium-term follow-up. Of 69 total children (mean age 9.2 years, 58% male), 60 (87%) had cardiovascular involvement with the most common features being troponin elevation in 33 (47%) and left ventricular dysfunction in 22 (32%). Based on presumed infection timing, 61 patients were sorted into variant cohorts of Alpha, Delta, and Omicron. Hospitalization was longer for the Delta group (7.7 days) vs Alpha (5.1 days, p = 0.0065) and Omicron (4.9 days, p = 0.012). Troponin elevation was more common in Delta compared to Alpha (13/20 vs 7/25, p = 0.18), and cumulative evidence of cardiac injury (echocardiographic abnormality and/or troponin elevation) was more common in Delta (17/20) compared with Alpha (12/25, p = 0.013) or Omicron (8/16, p = 0.034). Forty-nine (77%) of the original cohort (n = 69) had no cardiac symptoms or findings beyond 3 months post-hospitalization. Cardiac MRI was performed in 28 patients (between 3 and 6 months post-hospitalization) and was normal in 25 patients (89%). The differences in the variant cohorts may be due to alteration of the immune landscape with higher severity of COVID-19 infection. Despite overall reassuring cardiac outcomes, it is important to note the variability of presentation and remain vigilant with future variants.

Short-term and medium-term clinical outcomes of multisystem inflammatory syndrome in children: a prospective observational cohort study

BACKGROUND

Even though the incidence of Multisystem Inflammatory Syndrome in children (MIS-C) is decreasing cases are still reported across the world. Studying the consequences of MIS-C enhances our understanding of the disease's prognosis. The objective of this study was to assess short- and medium-term clinical outcomes of MIS-C.

METHODS

Prospective observational cohort study at Municipal Children's Hospital Morozovskaya, Moscow, Russia. All children meeting the Royal College of Paediatrics and Child Health (RCPCH), Centers for Disease Control and Prevention (CDC), or the World Health Organization (WHO) MIS-C case definition admitted to the hospital between 17 May and 26 October 2020 were included in the study. All survivors were invited to attend a clinic at 2 and 6 weeks after hospital discharge.

RESULTS

37 children median age 6 years (interquartile range [IQR] 3.3-9.4), 59.5% (22/37) boys were included in the study. 48.6% (18/37) of patients required ICU care. One child died. All children had increased levels of systemic inflammatory markers during the acute event. Echocardiographic investigations identified abnormal findings in 35.1% (13/37) of children. 5.6% (2/36) of children were presenting with any symptoms six weeks after discharge. By six weeks the inflammatory markers were within the reference norms in all children. The echocardiographic evaluation showed persistent coronary dilatation in one child.

CONCLUSIONS

Despite the severity of their acute MIS-C, the majority of children in our cohort fully recovered with none having elevated laboratory markers of inflammation at 6 weeks, few (< 10%) reporting persistent symptoms at 6 weeks, and only one with persistent echocardiographic abnormalities.

The impact of the COVID-19 pandemic on pediatric rheumatology practice: an international, cross-sectional survey study

OBJECTIVE

The COVID-19 pandemic has affected patient care in general. We aimed to analyze the impact of the pandemic on pediatric rheumatology practice.

METHODS

An online survey including 22 questions was created by the representatives of the Emerging RheumatoloGists and rEsearchers (EMERGE) group of the Pediatric Rheumatology European Society (PReS) on SurveyMonkey. The descriptive analysis of the responses was performed on SurveyMonkey.

RESULTS

Overall, 469 pediatric rheumatologists (F/M: 2.9) from 70 countries completed the survey. The practice of drug prescription is not affected by the pandemic, according to 65.3 % of the respondents, while 24.3 % and 16.5 % are prescribing biologic drugs and corticosteroids less often, respectively. Over 40 % of the respondents have seen an increased number of patients with vasculitis or chilblains during the pandemic. One-third of the respondents stated no adjustments in their clinical practice after 2.5 years of COVID-19 pandemic. The rest indicated implementing various changes, with an emphasis on incorporating telemedicine. Telemedicine constitutes ≥10 % of the clinical practice for one-third of the participants. Nonetheless, 35.5 % agree that there are still delays in patient care due to the pandemic. However, most (∼90 %) think our practice is returning to the pre-pandemic routine.

CONCLUSION

The findings of our study indicate a significant alteration in pediatric rheumatology practice due to the pandemic. This includes increased caution when prescribing anti-rheumatic drugs, a transition towards telemedicine utilization, delays in routine care, and a rise in COVID-19-related inflammatory conditions. It is imperative to address these aspects in order to improve patient care in pediatric rheumatology.

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

Background

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

Methods

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

Results

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

Conclusions

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