Multisystem inflammatory syndrome (MIS-C): a systematic review and meta-analysis of clinical characteristics, treatment, and outcomes

Complete Blood Count in Children With COVID-19: A Predictor of Disease Severity

Blood count abnormalities are frequent in patients with severe COVID-19 disease and there is still a lack of information in pediatric complete blood count (CBC) results. Thus, this study aims to correlate the CBC in the emergency room of children with COVID-19 between 0 and 10 years old and the clinical severity of the disease. A retrospective cohort study was performed in children with COVID-19 who collected at the emergency room CBC, C-reactive protein (CRP), platelet to lymphocyte ratio (PLR), neutrophil to lymphocyte ratio (NLR), neutrophil to monocyte ratio (NMR), lymphocyte to neutrophil ratio (LNR), lymphocyte to monocyte ratio (LMR), monocyte to neutrophil ratio (MNR) and monocyte to lymphocyte ratio (MLR). In total, demographic data from 93 children with median age of 19 months (0.3-126), 60.2% males, were included. The main changes in the CBC were atypical lymphocytes (51.6%) and eosinopenia (49.5%). From 69 hospitalized children, 21 were considered severe. There was no association between age, gender, and CRP value with clinical severity. The presence of underlying disease was five times higher (odds ratio [OR] = 5.08) in patients who required hospitalization and a higher NLR value was 54% (OR = 1.54) more likely to occur. Eosinopenia was three times more frequent in inpatients with disease severity criteria (OR = 3.05). In conclusion, children younger than 10 years of age with COVID-19 have changes in the CBC collected in the emergency room, mainly atypical lymphocytes and eosinopenia. The presence of a comorbidity or a higher NLR increases the chance of hospitalization. In addition, eosinopenia was a predictor of severity in inpatient children due to COVID-19.

Level of awareness regarding MIS-C among medical students and surgeons in Switzerland

Background

Multisystem inflammatory syndrome in children (MIS-C) is a disease that emerged during the COVID-19 pandemic. Patients exhibit symptoms mimicking the clinical presentation of an acute abdomen, representing a novel differential diagnosis, particularly in the young generation. This study aims to investigate the current level of awareness of MIS-C among surgeons and medical students.

Methods

We conducted an anonymous online questionnaire among members of the Swiss Surgical Society and Swiss medical students. The questionnaires collected participants' baseline demographics and their awareness regarding MIS-C.

Results

Both students and surgeons obtained very low scores in the self-assessment and had a low score in the section with awareness questions (true score). In medical students, we observed a positive correlation between self-assessment and true scores (ρ=0.422, p=0.001), while surgeons had a negative correlation (ρ=-0.243, p<0.001). Furthermore, there was a positive correlation between gender and self-assessment (ρ=0.245, p<0.001), depicting a higher self-assessed score in female surgeons (median female self-assesment=5, IQR: 2-7). Likewise, board-certified pediatric surgeons and surgeons treating both children and adults had a higher self-assessment compared with non-pediatric surgeons. In both populations (surgeons and students), the true scores were similar in all the variables analyzed. Two-thirds of surgeons stated that MIS-C should be considered a differential diagnosis, and about half of surgeons indicated MIS-C being part of their differential diagnosis already.

Conclusion

The results show an insufficient level of awareness concerning MIS-C among students and surgeons, warranting implementation in students' curriculum and surgeons' continuous training.

Coronary artery dilation in children with MIS-C: prevalence, risk factor, and progression

Cardiac injury is the critical issue in children with MIS-C, particularly coronary artery dilation. This study aimed to describe the prevalence, risk factors associated with coronary artery abnormalities, and their progression after 3 months of follow-up in MIS-C children in Vietnam. A prospective multicenter case series study was conducted on MIS-C patients diagnosed per WHO criteria from September 2021 to February 2023 at the two largest pediatric hospitals in southern Vietnam. Data on demographics, clinical features, laboratory findings, and treatments during the acute phase of MIS-C were collected. Patients were followed for 3 months post-discharge and categorized into normal and abnormal coronary artery groups for comparative analysis. Among 195 patients (mean age 6.3 years; male to female ratio 1.5:1), 33.3% exhibited coronary artery abnormalities at admission. Treatment included a combination of intravenous immunoglobulin (IVIG) and corticosteroids (53.3%), corticosteroids alone (42.6%), and IVIG alone (4.1%). After 3 months, only 3.6% of patients had persistent coronary artery abnormalities. Independent risk factors for coronary artery dilation included male sex (OR 4.59; 95% CI 1.62-12.94; p = 0.004), Kawasaki-like phenotype (OR 6.42; 95% CI 2.25-18.33; p = 0.001), and mesenteric lymphadenitis (OR 8.79; 95% CI 1.74-44.31; p = 0.008).

CONCLUSION

Coronary artery dilation in MIS-C patients shows a favorable recovery trajectory after a 3-month follow-up. Male sex, Kawasaki-like MIS-C, and mesenteric lymphadenitis are independent risk factors for coronary artery dilation in MIS-C patients.

WHAT IS KNOWN

• Multisystem inflammatory syndrome in children (MIS-C) is a severe inflammatory syndrome following SARS-CoV-2 infection, often leading to cardiac complications, particularly coronary artery dilation.

WHAT IS NEW

• Coronary artery dilation in MIS-C patients mostly resolves within three months of follow-up. Factors associated with coronary artery dilation in MIS-C patients include: male sex, Kawasaki-like phenotype and mesenteric lymphadenitis.

The Detection of COVID-19-Related Multivariate Biomarker Immune Response in Pediatric Patients: Statistical Aspects

The development of new point-of-care diagnostic testing tools for the detection of infectious diseases such as COVID-19 are a key aspect of clinical care and research. Accurate predictive classification methods are required to correctly identify and treat patients. Here, the onset of multisystem inflammatory syndrome in children (MIS-C), a more serious form of COVID-19, was predicted in a pediatric population using a set of multivariate immunological biomarker expression values. A first-stage bivariate detection of statistically significant biomarkers was obtained from a chosen set of standard cytokines and chemokine biomarkers considered relevant to COVID-19-related infection and disease. To incorporate the observed correlation structure among the resulting set of significant biomarkers, dimension reduction was then applied in the form of principal components. A second-stage logistic regression model using a small number of the principal component variables provided a highly predictive classification model for MIS-C. The resulting model was shown to compare favorably with an artificial neural network-based predictive model.

Evaluation of Pentraxin-3 levels in children with multisystem inflammatory syndrome

BACKGROUND

Early recognition of cardiac involvement and prediction of disease prognosis are essential for the management of inflammatory diseases such as multisystem inflammatory syndrome. This study aimed to investigate the role of Pentraxin-3 levels in identifying cardiac involvement and evaluating disease severity in patients with multisystem inflammatory syndrome.

METHODS

The study included 56 multisystem inflammatory syndrome patients and 26 healthy children as a control group. The multisystem inflammatory syndrome group was divided into those with cardiac involvement (n = 34) and those without (n = 22), as well as those with clinically mild-moderate (n = 30) and severe (n = 26) multisystem inflammatory syndrome. Blood samples for measurement of Pentraxin-3 levels were obtained from all patients before treatment and from the healthy controls.

RESULTS

In the patient group, the mean age was 8.2 ± 4 years (range: 2-17 years), and the male-to-female ratio was 1.8. In the control group, these values were 9.5 ± 3.7 years (range: 2-16 years) and 1.9, respectively (p > 0.05). Plasma Pentraxin-3 levels were significantly higher in multisystem inflammatory syndrome patients compared to controls (7.1 ± 5 ng/mL vs. 2.9 ± 2.1 ng/mL, p = 0.001). Patients with cardiac involvement had a significantly higher median Pentraxin-3 level than those without (5.8 ng/mL vs. 4.1 ng/mL, p = 0.004). Severe disease was also associated with a higher median Pentraxin-3 level compared to mild-moderate disease (6.1 ng/mL vs. 4.4 ng/mL, p = 0.001). Pentraxin-3 level was negatively correlated with left ventricular ejection fraction and positively correlated with B-type natriuretic peptide, troponin.

CONCLUSION

Elevated Pentraxin-3 levels in multisystem inflammatory syndrome patients may help predict the clinical course of the disease and cardiac involvement. However, larger-scale prospective studies are needed to further elucidate this.

COVID-19: Lessons Learned from Molecular and Clinical Research

SARS-CoV-2 virus, the etiological agent of the novel coronavirus disease 19 (COVID-19), was first identified in late 2019, following the sudden appearance of a cluster of pneumonia cases of unknown origin in China [...].

Investigating the Role of Gut Microbiota in Pediatric Patients with Severe COVID-19 or MIS-C

Severe COVID-19 and MIS-C are rare but serious outcomes associated with SARS-CoV-2 infection. The onset of MIS-C often involves the gastrointestinal system, suggesting a potential connection with gut microbiota. This study aims to compare the gut microbiota of children with severe COVID-19 and those with MIS-C using various biomolecular approaches. Gut microbiota composition and specific microbial modulations were analyzed using fecal samples collected at hospital admission. The study included hospitalized patients (mean age 6 ± 5 years) diagnosed with severe COVID-19 (37 patients) or MIS-C (37 patients). Microbial differences were assessed using both NGS and qRT-PCR methodologies. In 75% of cases, pharmacological treatments included antibiotics and corticosteroids, which influenced the microbiota composition. Early age was found to have the most significant impact on microbiota diversity. Significant differences in alpha and beta diversity were observed between COVID-19 and MIS-C patients, particularly concerning low-abundance species. Levels of Bacteroides spp., Bifidobacterium spp., and Akkermansia muciniphila were comparable between groups, while an increased activity of Bifidobacterium spp. was noted in children with positive fecal samples (p = 0.019). An in-depth evaluation of lesser-known gut species may be key to reducing the risk of severe outcomes and developing microbiota-based biomarkers for the early diagnosis of MIS-C.

Multidimensional 1-Year Outcomes After Intensive Care Admission for Multisystem Inflammatory Syndrome in Children

OBJECTIVES

The COVID-19 pandemic gave rise to uncertainty concerning potential sequelae related to a severe acute respiratory syndrome coronavirus 2 infection. This landscape is currently unfolding with studies reporting sequelae on various domains (physical, cognitive, and psychosocial), although most studies focus on adults or only one domain. We sought to investigate concurrent sequelae on multiple domains 1 year after PICU admission for Multisystem Inflammatory Syndrome in Children (MIS-C).

DESIGN

Prospective cohort study.

SETTING

Two academic, tertiary referral hospitals in The Netherlands and Belgium.

PATIENTS

Patients (< 18 yr, n = 58) seen in-person 1-year after PICU admission for MIS-C.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Seventy MIS-C patients (62% male; median age, 10.0 [interquartile range, 7.4-13.0]) were admitted to the PICU, mostly (86%) due to (imminent) circulatory failure. The majority received IV immunoglobulins (95%), steroids (83%), and vasopressors and/or inotropes (72%). Invasive respiratory support and extracorporeal membrane oxygenation were necessary in 7% and 2%, respectively. All patients survived. Fifty-eight patients (83%) attended 1-year follow-up. Although most patients had normal functional performance scores (Pediatric Cerebral Performance Category, Pediatric Overall Performance Category, and Functional Status Score), 62% still experienced physical sequelae: fatigue (40%), headaches (27%), and decreased exercise tolerance (19%). Cognitive, behavioral, and psychological problems were reported in 14%, 13%, and 23%, respectively. This resulted in 22% requiring ongoing healthcare utilization, 9% not being able to return to full-time school attendance and cessation of hobbies in 7%.

CONCLUSIONS

This is the first 1-year outcome study of MIS-C PICU patients to include both physical and psychosocial characteristics. One year after PICU admission, most children had normalized functional performance as measured by three validated performance scores. However, many still reported a variety of multidimensional sequelae at 1-year follow-up impacting daily life. This emphasizes the importance of continued investigative efforts and multidisciplinary follow-up programs to better understand pathophysiology and contributing factors to the MIS-C disease trajectory and initiate patient-specific interventions to improve outcome and social participation.

Cardiovascular hospitalizations and deaths in adults, children and pregnant women

Cardiovascular diseases (CVDs) and strokes are the leading cause of death worldwide. To estimate the number and incidence of cardiovascular hospitalizations and deaths in adults and children and strokes and acute coronary syndromes (ACS) among pregnant women in France. Using National Health Data, we identified all hospitalizations for CVD in 2022 and cardiovascular deaths in 2021. We also identified all women in the general health insurance scheme who gave birth in France during 2010-2018 after 22 weeks' gestation and all strokes and ACS that occurred during pregnancy and postpartum. In adults in 2022, there were 1,229,003 hospitalizations for CVD among 925,936 adults (59.2% men) for a standardized rate of 1614 per 100,000. This was twice as high in men versus women and increased with age and social deprivation. In 2021, 138,137 adults died of CVD (47.4% men), i.e. 216 per 100,000 adults. Among children born during the first 6 months of 2022, a congenital heart defect (CHD) was identified in 3876 (1068 cases per 100,000 live births). In 2021, 193 children died of a CHD (1.4 per 100,000) and 100 of another CVD (0.7 per 100,000). In the women accounting for the 6.3 million deliveries during 2010-2018, 1261 strokes and 225 ACS were identified during pregnancy and the postpartum period, i.e. respective incidence rates of 24.0 and 4.3 per 100,000 person-years. The burden of CVD calls for large-scale action to improve the prevention, screening and management of CVD in these different populations.

In-hospital unfavorable outcomes of MIS-C during 2020-2022: a systematic review

Studies on the severity in multisystem inflammatory syndrome in children (MIS-C) show heterogeneous results and may not reflect a global perspective. This systematic review aims to estimate the frequency of in-hospital unfavorable outcomes in patients with MIS-C over the 3 years since the onset of the SARS-CoV-2 pandemic. A systematic search was conducted in Medline, Scopus, Embase, Cochrane, Web of Science, Scielo, and preprint repositories until December 15, 2022. Study selection and data extraction were evaluated independently. The primary outcomes were intensive care unit (ICU) admission, invasive mechanical ventilation (IMV), and death. Additionally, we evaluated cardiovascular-related outcomes. We performed a random-effects model meta-analysis and assessed the certainty of the evidence. Fifty-seven studies (n = 13 254) were included. The frequency of ICU admission was 44.7% (95% CI 38.8-50.7), 11.9% for IMV (95% CI 9.6-14.4), and 2.0% for death (95% CI 1.3-3.0). The requirement of vasoactive/inotropic drugs was 40.1% (95% CI 35.9-44.4), 7.9% for coronary aneurysm (95% CI 4.1-12.7), 30.7% for decreased left ventricle ejection fraction (LVEF) (95% CI 26.3-35.4), and 29.7% for myocarditis (95% CI 18.4-42.4). We assess the included evidence as being of very low certainty. Finally, excess COVID-19 mortality by country and the diagnostic criteria for MIS-C (CDC compared to WHO) were associated with a higher frequency of ICU admissions. The year of study conduction (2022 compared to 2020) was associated with a lower frequency of IMV.

CONCLUSION

The frequency of in-hospital unfavorable outcomes in patients with MIS-C was high. Well-designed studies are needed to explore other heterogeneity sources.

PROTOCOL REGISTRATION

CRD42021284878.

WHAT IS KNOWN

• Multisystem inflammatory syndrome in children (MIS-C) is a serious post-infectious condition linked to SARS-CoV-2. Studies on the severity of MIS-C show heterogeneous results. These findings may not be representative of the reality in other regions, making it challenging to draw generalizable conclusions.

WHAT IS NEW

• Over the 3 years since the onset of the SARS-CoV-2 pandemic, our systematic review has shown that the frequency of in-hospital unfavorable outcomes in patients with MIS-C is high, with a very low certainty of the evidence. Our results reflect the reality from a global perspective, across different countries with varying income levels. • The main sources of heterogeneity in the frequency of severe outcomes could be explained by the excess mortality due to COVID-19 in each country, the type of diagnostic criteria for MIS-C, and the year the study was conducted.

The Impact of BMI on Ventricular Function Recovery in Children After Pediatric Inflammatory Multisystem Syndrome (PIMS-TS)

Objectives: The goal of this study was to assess if body mass index (BMI) affects the pace of cardiac muscle recovery in children after Pediatric Inflammatory Multisystem Syndrome Temporally Associated with SARS-CoV-2/COVID-19 (PIMS-TS). Methods: A prospective single-center study enrolled consecutive children hospitalized with PIMS-TS between October 2020 and February 2022 and followed up after 6 weeks and 6 months. In all children, three-dimensional echocardiography and global longitudinal strain were used to assess ventricular function and the results were analyzed according to patients' BMI status. Results: This study enrolled 170 patients aged 1-17 years, median 8.5 ± 4.43 years. Children with normal BMI (>5th and <85th percentile; n = 115) accounted for 67.65%, overweight and obese children (>85th percentile; n = 40) accounted for 23.53% and underweight children (<5th percentile; n = 15) accounted for 8.82% of the participants. In all patients, the means of left and right ventricular ejection fractions (LVEF and RVEF) in 3D-ECHO and average GLS were within normal limits at discharge and during follow-up. However, in children with normal weight, the function of the left ventricle improved between 6 weeks and 6 months according to both GLS and LVEF (respectively: LV GLS -20.19 ± 3.88% and -23.17 ± 2.58, p < 0.05; LVEF 60.68 ± 2.64% and 63.58 ± 2.49%, p < 0.05), while no significant improvement was observed in underweight, overweight and obese children. In patients with BMI > 85th percentile, the mean of left ventricular GLS after 6 weeks, although in the normal range, was significantly lower than in underweight children (respectively: -20.09 ± 2.5% and -23.55 ± 3.55%, p = 0.002), whereas left ventricle function assessed with 3D-ECHO showed no significant difference in both groups at that time (BMI > 85th percentile LVEF 61.15 ± 3.21%, BMI < 5th percentile LVEF 61.30 ± 2.71%, p = 0.36). During the study period, right ventricular function remained within normal limits and no significant differences according to both GLS and RVEF were reported between weight status groups. However, further significant right ventricular function improvement between 6 weeks and 6 months was observed in children with normal weight according to GLS (respectively: -22.6 ± 4.51% and -24.16 ± 2.97%, p = 0.02), while RVEF in 3D-ECHO remained unchanged (respectively: 64.01 ± 3.61% and 64.53 ± 3.15%, p = 0.63). In groups of underweight, overweight and obese children, no significant changes between 6 weeks and 6 months were observed (BMI < 5th percentile RVEF at 6 weeks 66.20 ± 2.86% and BMI < 5th percentile RVEF at 6 months 65.20 ± 2.28%, p = 0.58; BMI > 85th percentile RVEF at 6 weeks 63.44 ± 3.00% and BMI > 85th percentile RVEF at 6 months 64.11 ± 2.52%, p = 0.58). Conclusions: Left and right ventricular function stayed within normal limits 6 weeks after PIMS-TS regardless of patients' BMI. Left and right ventricular function improved further between 6 weeks and 6 months after acute disease in the group of children with normal BMI. GLS is a sensitive tool for its assessment. Lower ventricular GLS in children with BMI > 85th percentile may indicate poorer left ventricular performance. Children with normal BMI may present with a more advantageous cardiac recovery pace after PIMS-TS.

Characteristics of Multisystem Inflammatory Syndrome in Children Across COVID-19 Variants in Vojvodina

Background/Objectives: To investigate if the severity and presentation of multisystem inflammatory syndrome in children (MIS-C) vary between different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. Methods: This retrospective study included 59 patients aged 0-18 years, diagnosed with COVID-19 and MIS-C, treated and monitored over a one-year period after discharge from hospital. The patients were grouped according to the predominant SARS-CoV-2 variant. The predominant variant of SARS-CoV-2 was assumed by the date of hospitalization. The following patient data were collected: demographic data (age, sex), information on comorbidities, body mass index, clinical data (fever and duration of febrile periods, symptoms of Kawasaki-like phenotypes, and presence of respiratory, cardiovascular, gastrointestinal, neurological and other symptoms), and laboratory and imaging findings. Results: In total, 24 (41%), 19 (32%), and 15 (25%) patients were diagnosed with MIS-C during the Alpha, Delta, and Omicron periods, respectively (63.8% were males; 36.2% were females). Comorbidities were present in 49% of patients. Respiratory symptoms were the most common during the Delta period (73%, p = 0.028). There was no statistically significant difference in the occurrence of other symptoms, laboratory findings, treatment, complications, and long-term outcomes between groups. Conclusions: No significant correlation was found between hospitalization date (used to estimate COVID-19 variant) and presentation/severity of MIS-C.

Long-term health outcome and quality of life in children with multisystem inflammatory syndrome: findings from multidisciplinary follow-up at an Italian tertiary-care paediatric hospital

Multisystem inflammatory syndrome is a severe complication of SARS-CoV-2 infection in children (MIS-C). To date, data on long-term sequelae mainly concern cardiac outcomes. All ≤ 18 year olds consecutively admitted to the Buzzi Children's Hospital with a diagnosis of MIS-C between October 1, 2020, and May 31, 2022, were followed up for up to 12 months by a dedicated multidisciplinary team. They underwent laboratory tests, multi-organ clinical and instrumental assessments, and psychosocial evaluation. 56/62 patients, 40 M, mean age 8.7 years (95% CI 7.7, 9.7), completed the follow-up. Cardiological, gastroenterological, pneumological, and neurological evaluations, including IQ and EEG, were normal. Alterations of HOMA-IR index and/or TyG index, observed in almost all patients during hospitalisation, persisted in about a third of the population at 12 months. At 6 and 12 months respectively, impairment of adaptive functions was observed in 38/56 patients (67.9%) and 25/56 (44.6%), emotional and behavioural problems in 10/56 (17.9%) and 9/56 (16.1%), and decline in QoL in 14/56 (25.0%) and 9/56 (16.1%). Psychosocial well-being impairment was significantly more frequent in the subgroup with persistent glycometabolic dysfunction at 12 months (75% vs. 40.9% p < 0.001).

CONLUSION

The mechanisms that might explain the long-term persistence of both metabolic alterations and neuro-behavioural outcomes and their possible relationship are far from being clarified. Our study points out to the potential long-term effects of pandemics and to the importance of a multidisciplinary follow-up to detect potential negative sequelae in different areas of health, both physical and psychosocial.

WHAT IS KNOWN

• Multisystem inflammatory syndrome in children (MIS-C) is a severe complication of SARS-CoV-2 infection. • Few data exist on the medium- and long-term outcomes of MIS-C, mostly focused on cardiac involvement. Emerging evidence shows neurological and psychological sequelae at mid- and long-term follow-up.

WHAT IS NEW

• This study reveals that MIS-C may lead to long-term glycometabolic dysfunctions joined to impairment in the realm of general well-being and decline in quality of life, in a subgroup of children. • This study highlights the importance of a long-term multidisciplinary follow-up of children hospitalised with MIS-C, in order to detect the potential long-term sequelae in different areas of health, both physical and psychosocial well-being.

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.

Multisystem inflammatory syndrome in children: A review

AIM

To comprehensively review the literature on multisystem inflammatory syndrome in children (MIS-C).

METHODS

Narrative review of relevant studies published between April 2020 and January 2024.

RESULTS

MIS-C is a SARS-CoV-2-related hyperinflammatory syndrome developing 2-6 weeks after COVID-19 in genetically susceptible individuals. Persisting fever, mucocutaneous manifestations, GI and cardiac involvement, together with lymphopenia and elevated inflammatory and cardiac markers are the main clinical features. It is believed to recognise some pathogenetic and clinical overlap with Kawasaki disease. New case definitions have been proposed after an assessment of the diagnostic performance of existing criteria; epidemiological criterion is however progressively losing its usefulness as the pandemic turns into an endemic and in the areas with the highest rates of COVID-19 vaccination. Current guidelines recommend both intravenous immunoglobulin and glucocorticoids in the first-line immunomodulatory treatment, mainly based on comparative retrospective cohorts; the actual role of biologics remains to be adequately established. Strict follow-up is mandatory, especially for those with severe cardiac involvement, as longitudinal studies evaluate the long-term evolution of cardiac damage.

CONCLUSION

In this paper, we review the epidemiological, pathogenetic, clinical and prognostic features of MIS-C, and outline the main questions which still remain unanswered after more than 3 years of research.

The Spectrum of Postacute Sequelae of COVID-19 in Children: From MIS-C to Long COVID

The effects of SARS-CoV-2 infection on children continue to evolve following the onset of the COVID-19 pandemic. Although life-threatening multisystem inflammatory syndrome in children (MIS-C) has become rare, long-standing symptoms stemming from persistent immune activation beyond the resolution of acute SARS-CoV-2 infection contribute to major health sequelae and continue to pose an economic burden. Shared pathophysiologic mechanisms place MIS-C and long COVID within a vast spectrum of postinfectious conditions characterized by intestinal dysbiosis, increased gut permeability, and varying degrees of immune dysregulation. Insights obtained from MIS-C will help shape our understanding of the more indolent and prevalent postacute sequelae of COVID and ultimately guide efforts to improve diagnosis and management of postinfectious complications of SARS-CoV-2 infection in children.

SARS-CoV-2 parental vaccination and risk of multisystem inflammatory syndrome in children: a single-center retrospective study

Purpose

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) usually causes a mild disease in children and the most serious consequence is multisystem inflammatory syndrome in children (MIS-C). Currently, there are no data about the protective role of vaccination performed by parents on children regarding the development of MIS-C. The aim of our study is to establish whether parental vaccination is related to MIS-C and the protective value of SARS-CoV-2 vaccination performed by parents against the occurrence of MIS-C in their children.

Materials and Methods

Our retrospective single center study included 124 patients aged 1 month to 18 years admitted to emergency department from April 2020 to March 2022 for coronavirus disease 2019 disease.

Results

Parental vaccination was negatively correlated with the development of MIS-C: 4% of patients with both parents vaccinated developed MIS-C, while patients with no parent vaccinated to have developed MIS-C were 20%.

Conclusion

Parental vaccination could be an important factor influencing the course of the disease and reduces the probability that a child would develop MIS-C by 83% if both parents vaccinated.

Inflammatory and Autoimmune Aspects of Multisystem Inflammatory Syndrome in Children (MIS-C): A Prospective Cohort Study

Multisystem Inflammatory Syndrome in Children (MIS-C) is a potentially life-threatening complication of COVID-19. The pathophysiological mechanisms leading to severe disease are poorly understood. This study leveraged clinical samples from a well-characterized cohort of children hospitalized with COVID-19 or MIS-C to compare immune-mediated biomarkers. Our objective was to identify selected immune molecules that could explain, in part, why certain SARS-CoV-2-infected children developed MIS-C. We hypothesized that type-2 helper T cell-mediated inflammation can elicit autoantibodies, which may account for some of the differences observed between the moderate-severe COVID-19 (COVID+) and MIS-C cohort. We enumerated blood leukocytes and measured levels of selected serum cytokines, chemokines, antibodies to COVID-19 antigens, and autoantibodies in children presenting to an academic medical center in Connecticut, United States. The neutrophil/lymphocyte and eosinophil/lymphocyte ratios were significantly higher in those in the MIS-C versus COVID+ cohort. IgM and IgA, but not IgG antibodies to SARS-CoV-2 receptor binding domain were significantly higher in the MIS-C cohort than the COVID+ cohort. The serum levels of certain type-2 cytokines (interleukin (IL)-4, IL-5, IL-6, IL-8, IL-10, IL-13, and IL-33) were significantly higher in children with MIS-C compared to the COVID+ and SARS-CoV-2-negative cohorts. IgG autoantibodies to brain antigens and pentraxin were higher in children with MIS-C compared to SARS-CoV-19-negative controls, and children with MIS-C had higher levels of IgG anti-contactin-associated protein-like 2 (caspr2) compared to the COVID+ and SARS-CoV-19-negative controls. We speculate that autoimmune responses in certain COVID-19 patients may induce pathophysiological changes that lead to MIS-C. The triggers of autoimmunity and factors accounting for type-2 inflammation require further investigation.

Clinical presentation, diagnosis and management of multisystem inflammatory syndrome in children (MIS-C): a systematic review

BACKGROUND

Knowledge about multisystem inflammatory syndrome in children (MIS-C) is evolving, and evidence-based standardised diagnostic and management protocols are lacking. Our review aims to summarise the clinical and diagnostic features, management strategies and outcomes of MIS-C and evaluate the variances in disease parameters and outcomes between high-income countries (HIC) and middle-income countries (MIC).

METHODS

We searched four databases from December 2019 to March 2023. Observational studies with a sample size of 10 or more patients were included. Mean and prevalence ratios for various variables were pooled by random effects model using R. A mixed generalised linear model was employed to account for the heterogeneity, and publication bias was assessed via funnel and Doi plots. The primary outcome was pooled mean mortality among patients with MIS-C. Subgroup analysis was conducted based on the income status of the country of study.

RESULTS

A total of 120 studies (20 881 cases) were included in the review. The most common clinical presentations were fever (99%; 95% CI 99.6% to 100%), gastrointestinal symptoms (76.7%; 95% CI 73.1% to 79.9%) and dermatological symptoms (63.3%; 95% CI 58.7% to 67.7%). Laboratory investigations suggested raised inflammatory, coagulation and cardiac markers. The most common management strategies were intravenous immunoglobulins (87.5%; 95% CI 82.9% to 91%) and steroids (74.7%; 95% CI 68.7% to 79.9%). Around 53.1% (95% CI 47.3% to 58.9%) required paediatric intensive care unit admissions, and overall mortality was 3.9% (95% CI 2.7% to 5.6%). Patients in MIC were younger, had a higher frequency of respiratory distress and evidence of cardiac dysfunction, with a longer hospital and intensive care unit stay and had a higher mortality rate than patients in HIC.

CONCLUSION

MIS-C is a severe multisystem disease with better mortality outcomes in HIC as compared with MIC. The findings emphasise the need for standardised protocols and further research to optimise patient care and address disparities between HIC and MIC.

PROSPERO REGISTRATION NUMBER

CRD42020195823.

COVID-19 ethics: unique aspects and a review as of early 2024

COVID-19 presents a variety of ethical challenges in a set of arenas, arenas not always considered in past pandemics. These challenges include issues related to autonomy, distributive ethics, and the establishment of policies of equity and justice. Methods are a literature review based on regular editing of an online textbook during the COVID-19 outbreak and a literature review using key ethical terms. Patients are confronted with new issues related to autonomy. Providers need to expand their concepts of ethical issues to include decisions based on proportionality and public health ethics. The public health sector needs to assess the beneficence of alternative modes of disease control. The research community needs to redefine the concept of informed consent in emergent conditions. All elements of the medical spectrum-physicians, scientists, and the community-at-large including the pharmaceutical industry-need to consider the multifaceted methods for preventing future pandemics. This will require giving particular emphasis to public health funding and ending the documented discrimination that exists in the provision of proven therapies. The developing world is especially at risk for most of the ethical issues, especially those related to equity and justice. The ethical issues associated with the COVID-19 outbreak are not unique but provide a diverse set of issues that apply to patients, providers, social groups, and investigators. The further study of such issues can help with preventing future outbreaks.

Therapeutic implications of quercetin and its derived-products in COVID-19 protection and prophylactic

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel human coronavirus, which has triggered a global pandemic of the coronavirus infectious disease 2019 (COVID-19). Outbreaks of emerging infectious diseases continue to challenge human health worldwide. The virus conquers human cells through the angiotensin-converting enzyme 2 receptor-driven pathway by mostly targeting the human respiratory tract. Quercetin is a natural flavonoid widely represented in the plant kingdom. Cumulative evidence has demonstrated that quercetin and its derivatives have various pharmacological properties including anti-cancer, anti-hypertension, anti-hyperlipidemia, anti-hyperglycemia, anti-microbial, antiviral, neuroprotective, and cardio-protective effects, because it is a potential treatment for severe inflammation and acute respiratory distress syndrome. Furthermore, it is the main life-threatening condition in patients with COVID-19. This article provides a comprehensive review of the primary literature on the predictable effectiveness of quercetin and its derivatives docked to multi-target of SARS-CoV-2 and host cells via in silico and some of validation through in vitro, in vivo, and clinically to fight SARS-CoV-2 infections, contribute to the reduction of inflammation, which suggests the preventive and therapeutic latency of quercetin and its derived-products against COVID-19 pandemic, multisystem inflammatory syndromes (MIS), and long-COVID.

Severe pediatric COVID-19: a review from the clinical and immunopathophysiological perspectives

BACKGROUND

Coronavirus disease 2019 (COVID-19) tends to have mild presentations in children. However, severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times, meriting further attention from clinicians. Meanwhile, the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely understood.

DATA SOURCES

A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed, Embase, and Wanfang databases. Searched keywords included "COVID-19 in children", "severe pediatric COVID-19", and "critical illness in children with COVID-19".

RESULTS

Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated status. Acute respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations, while various forms of cardiovascular and neurological involvement may also be seen. Multiple immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways, whose dysregulation in severe and critical diseases translates into adverse clinical manifestations. Multisystem inflammatory syndrome in children (MIS-C), a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure, denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric immunity. Despite the considerable dissimilarities between the pediatric and adult immune systems, clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult guidelines.

CONCLUSIONS

Severe pediatric COVID-19 can affect multiple organ systems. The dysregulated immune pathways in severe COVID-19 shape the disease course, epitomize the vast functional diversity of the pediatric immune system and highlight the immunophenotypical differences between children and adults. Consequently, further research may be warranted to adequately address them in pediatric-specific clinical practice guidelines.

Vitamin D Supplementation in Neonatal and Infant MIS-C Following COVID-19 Infection

To date, the SARS-CoV-2 pandemic still represents a great clinical challenge worldwide, and effective anti-COVID-19 drugs are limited. For this reason, nutritional supplements have been investigated as adjuvant therapeutic approaches in disease management. Among such supplements, vitamin D has gained great interest, due to its immunomodulatory and anti-inflammatory actions both in adult and pediatric populations. Even if there is conflicting evidence about its prevention and/or mitigation effectiveness in SARS-CoV-2 infection, several studies demonstrated a strict correlation between hypovitaminosis D and disease severity in acute COVID-19 and MIS-C (multisystem inflammatory syndrome in children). This narrative review offers a resume of the state of the art about vitamin D's role in immunity and its clinical use in the context of the current pandemic, specially focusing on pediatric manifestations and MIS-C. It seems biologically reasonable that interventions aimed at normalizing circulating vitamin D levels could be beneficial. To help clinicians in establishing the correct prophylaxis and/or supportive therapy with vitamin D, well-designed and adequately statistically powered clinical trials involving both adult and pediatric populations are needed. Moreover, this review will also discuss the few other nutraceuticals evaluated in this context.

High Fatality Rates in Pediatric Multisystem Inflammatory Syndrome: A Multicenter Experience From the Epicenter of Brazil's Coronavirus Pandemic

BACKGROUND

Brazil´s case fatality rate (CFR) of pediatric multisystem inflammatory syndrome in children and adolescents (MIS-C) is among the highest worldwide. Despite these concerns, limited hospital-based and comprehensive pediatric data have been published on MIS-C in Brazilian children.

METHODS

We performed a descriptive analysis of the MIS-C scores in 16 public and private hospitals providing secondary and tertiary care in the metropolitan area of São Paulo, Brazil. Clinical and demographic information were systematically extracted from the electronic medical records of each patient. Logistic regression analysis was performed to identify the combined effects of MIS-C phenotype, disease severity and comorbidity as dependent variables.

RESULTS

A total of 101 patients met the MIS-C criteria and were evaluated. The median age was 67 months, 60% were male, 28.7% were black or afrodescendant and 62.3% were admitted to public hospitals. Underlying medical conditions were observed in 16.8% of patients and were associated with a longer duration of hospitalization. A Kawasaki disease-like phenotype was observed in 43.5% of patients, and they demonstrated a trend of lower median age. Children with severe MIS-C were older (median age 91 months vs. 36 months) and had a nonspecific phenotype, more cardiovascular and respiratory involvement and kidney injury; 73.3% required intensive care, 20.8% required mechanical ventilation and 35.6% required inotropic support. Four deaths occurred (CFR = 3.9%), three of which were in healthy participants.

CONCLUSION

We identified a lower median age, particularly among children with Kawasaki disease-like phenotypes, those with a significant need for intensive care, and a high CFR in MIS-C. Our findings confirmed the increased severity of the disease in the selected Brazilian population.

Parental concerns and vaccine hesitancy against COVID-19 vaccination for children in Greece: A cross-sectional survey

INTRODUCTION

Parental hesitancy against children's COVID-19 vaccination remains a challenge globally. Although many studies have explored parental hesitancy, less is known about parental intentions towards COVID-19 vaccination of 6-month to 4-year-old children who were the last age group that became eligible for vaccination and for older children throughout the Omicron predominance period.

METHODS

We conducted a nationwide cross-sectional survey from November to December 2022 in Greece. We aimed to explore parental COVID-19 vaccination intentions for their children, reasons against vaccination, and to estimate the association between parents' intentions and child and parental characteristics and parental attitudes towards COVID-19 vaccination.

RESULTS

Of 431 parents, 243 (56.4 %) had not or did not intend to vaccinate their children against COVID-19. Most parents were vaccinated against COVID-19 (64.7 % no booster; 14.2 % at least one booster). Among parents with children under the age of 5, 13.0 % intended to vaccinate their children against COVID-19, while 47.3 % of parents with children 5 years of age or older reported intention or had already completed vaccination. The most common reasons against COVID-19 vaccination were fear of side effects (32.9 %), perceived short length of clinical trials (29.2 %), and the child having previously contracted COVID-19 (12.0 %). The strongest factors associated with intention or already completed vaccination were parental own vaccination against COVID-19, using a pediatrician or a healthcare professional as the main source of vaccine-related information for their children, agreeing with their pediatrician regarding COVID-19 vaccination, and trusting official healthcare guidelines. Stratified analyses by the two children's age groups (<5 and 5 to 17) yielded similar estimates. Among parents who had not or did not intend to vaccinate their children, 11.9 % would do so if recommended by a pediatrician.

CONCLUSIONS

Our findings highlight the need to incentivize healthcare professionals and pediatricians to inform parents about vaccines, clarify misconceptions and address concerns.

Multisystem inflammatory syndrome in 1.2 million children: longitudinal cohort study of risk factors

BACKGROUND

We identified patient characteristics associated with an increased risk of developing MIS-C.

METHODS

We conducted a longitudinal cohort study of 1,195,327 patients aged 0-19 years between 2006 and 2021, including the first two waves of the pandemic (February 25-August 22, 2020 and August 23, 2020-March 31, 2021). Exposures included prepandemic morbidity, birth outcomes, and family history of maternal disorders. Outcomes included MIS-C, Kawasaki disease, and other Covid-19 complications during the pandemic. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) for the association between patient exposures and these outcomes using log-binomial regression models adjusted for potential confounders.

RESULTS

Among 1,195,327 children, 84 developed MIS-C, 107 Kawasaki disease, and 330 other Covid-19 complications during the first year of the pandemic. Prepandemic hospitalizations for metabolic disorders (RR 11.3, 95% CI 5.61-22.6), atopic conditions (RR 3.34, 95% CI 1.60-6.97), and cancer (RR 8.11, 95% CI 1.13-58.3) were strongly associated with the risk of MIS-C, compared with no exposure. These same exposures were also associated with Kawasaki disease and other Covid-19 complications. However, birth characteristics and history of maternal morbidity were not associated with MIS-C development.

CONCLUSIONS

Children with pre-existing morbidity have a considerably elevated risk of MIS-C.

IMPACT

Morbidities that predispose children to multisystem inflammatory syndrome (MIS-C) are unclear. In this study, prepandemic hospitalizations for metabolic disorders, atopic conditions, and cancer were associated with an elevated risk of MIS-C. Birth characteristics and family history of maternal morbidity were not, however, associated with MIS-C. Pediatric morbidities may play a greater role in MIS-C onset than maternal or perinatal characteristics, and may help clinicians better recognize children at risk for this complication.

Prognostic factors for multisystem inflammatory syndrome in children: A systematic review and meta-analysis

AIM

Multisystem inflammatory syndrome in children (MIS-C) is a novel condition that can occur post-SARS-CoV-2 infection in children and adolescents. There is a paucity of evidence on the prognostic factors associated with MIS-C. The aim of this systematic review and meta-analysis was to summarise the prognostic factors for MIS-C development.

METHODS

Five databases were systematically searched from January 2020 to May 2023 for studies reporting on prognostic factors for MIS-C using multivariable regression models. Random-effects meta-analyses were conducted to pool odds ratios for each prognostic factor. Risk of bias was rated using QUIPS and the GRADE framework was used to assess the certainty of evidence for each unique factor.

RESULTS

Twelve observational studies (N = 18 024) were included, and 13 unique prognostic factors were amenable to meta-analysis. With moderate certainty, age <12 years, male sex and Black race probably increase the risk of MIS-C. Malignancy and underlying respiratory disease probably decrease the risk of MIS-C. Low-certainty evidence suggests that Asian race may increase the risk of MIS-C, and comorbidity may decrease the risk of MIS-C.

CONCLUSION

Current literature presents several prognostic factors related to MIS-C following SARS-CoV-2 infection. Further research is necessary to elucidate the pathophysiologic mechanisms related to MIS-C.

"Multisystem Inflammatory Syndrome in Children"-Like Disease after COVID-19 Vaccination (MIS-V) with Potential Significance of Functional Active Autoantibodies Targeting G-Protein-Coupled Receptors (GPCR-fAAb) for Pathophysiology and Therapy

BACKGROUND

An infection with SARS-CoV-2 can trigger a systemic disorder by pathological autoimmune processes. A certain type of this dysregulation is known as Multisystemic inflammatory syndrome in children (MIS-C). However, similar symptoms may occur and have been described as Multisystemic inflammatory syndrome after SARS-CoV-2 Vaccination (MIS-V) following vaccination against SARS-CoV-2. We report the case of a 12-year-old boy who was identified with MIS-C symptoms without previous SARS-CoV-2 infection after receiving two doses of the Pfizer-BioNTech COVID-19 vaccine approximately one month prior to the onset of symptoms. He showed polyserositis, severe gastrointestinal symptoms and, consequently, a manifestation of a multiorgan failure. IgG antibodies against spike proteins of SARS-CoV-2 were detected, indicating a successful vaccination, while SARS-CoV-2 Nucleocapsid protein antibodies and SARS-CoV-2 PCR were not detected. Several functional, active autoantibodies against G-protein-coupled receptors (GPCR-fAAb), previously associated with Long COVID disease, were detected in a cardiomyocyte bioassay. Immunosuppression with steroids was initiated. Due to side effects, treatment with steroids and later interleukin 1 receptor antagonists had to be terminated. Instead, immunoadsorption was performed and continued with tacrolimus and mycophenolic acid therapy, leading to improvement and discharge after 79 days. GPCR-fAAb decreased during therapy and remained negative after clinical curing and under continued immunosuppressive therapy with tacrolimus and mycophenolic acid. Follow-up of the patient showed him in good condition after one year.

CONCLUSIONS

Infection with SARS-CoV-2 shows a broad and severe variety of symptoms, partly due to autoimmune dysregulation, which, in some instances, can lead to multiorgan failure. Despite its rarity, post-vaccine MIS-C-like disease may develop into a serious condition triggered by autoimmune dysregulation. The evidence of circulating GPCR-fAAb and their disappearance after therapy suggests a link of GPCR-fAAb to the clinical manifestations. Thus, we hypothesize a potential role of GPCR-fAAb in pathophysiology and their potential importance for the therapy of MIS-C or MIS-V. However, this observation needs further investigation to prove a causative correlation.

Multisystem inflammatory syndrome in children (MIS-C): Implications for long COVID

The COVID-19 pandemic caused by the coronavirus 2 of the severe acute respiratory syndrome (SARS-CoV-2) has significantly affected people around the world, leading to substantial morbidity and mortality. Although the pandemic has affected people of all ages, there is increasing evidence that children are less susceptible to SARS-CoV-2 infection and are more likely to experience milder symptoms than adults. However, children with COVID-19 can still develop serious complications, such as multisystem inflammatory syndrome in children (MIS-C). This narrative review of the literature provides an overview of the epidemiology and immune pathology of SARS-CoV-2 infection and MIS-C in children. The review also examines the genetics of COVID-19 and MIS-C in children, including the genetic factors that can influence the susceptibility and severity of the diseases and their implications for personalized medicine and vaccination strategies. By examining current evidence and insights from the literature, this review aims to contribute to the development of effective prevention and treatment strategies for COVID-19, MIS-C, and long COVID syndromes in children.

Three-Dimensional Echocardiography and Global Longitudinal Strain in Follow-Up After Multisystem Inflammatory Syndrome in Children: Six-Month, Single-Center, Prospective Study

OBJECTIVE

To assess the potential long-term cardiac effects after multisystem inflammatory syndrome in children (MIS-C) with cardiovascular involvement in the acute phase.

STUDY DESIGN

Our prospective study involved children consecutively diagnosed with MIS-C between October 2020 and February 2022 and followed 6 weeks and 6 months after the disease. In patients with severe cardiac involvement during the acute phase, an additional check-up after 3 months was scheduled. In all patients at all check-ups, 3-dimensional echocardiography and global longitudinal strain (GLS) were used to assess ventricular function.

RESULTS

The study enrolled 172 children aged 1-17 years (median, 8 years). The means of ejection fraction (EF) and GLS for both ventricles were within normal limits after 6 weeks with no relationship with initial severity: left ventricular EF (LVEF) 60% (59%-63%), LV GLS -21.08% (-18.63% to -23.2%), right ventricular (RV) EF 64% (62%-67%), and RV GLS -22.8% (-20.5% to -24.5%). Further, statistically significant improvement of LV function was observed after 6 months-LVEF 63% (62%-65%) and LV GLS -22.55% (-21.05% to -24.25%; P < .05); however, RV function remained unchanged. The group with severe cardiac involvement showed LV function recovery pattern with no significant improvement between 6 weeks and 3 months after MIS-C, while still improving between 3 and 6 months after discharge.

CONCLUSIONS

LV and RV function is within normal limits 6 weeks after MIS-C regardless of severity of cardiovascular involvement; LV function improves further between 6 weeks and 6 months after the disease. The long-term prognosis is optimistic with full recovery of cardiac function.

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.

The Management of COVID-19-Related Coagulopathy: A Focus on the Challenges of Metabolic and Vascular Diseases

The course of COVID-19 is highly dependent on the associated cardiometabolic comorbidities of the patient, which worsen the prognosis of coronavirus infection, mainly due to systemic inflammation, endothelium dysfunction, and thrombosis. A search on the recent medical literature was performed in five languages, using the PubMed, Embase, Cochrane, and Google Scholar databases, for the review of data regarding the management of patients with a high risk for severe COVID-19, focusing on the associated coagulopathy. Special features of COVID-19 management are presented, based on the underlying conditions (obesity, diabetes mellitus, and cardiovascular diseases), emphasizing the necessity of a modern, holistic approach to thromboembolic states. The latest findings regarding the most efficient therapeutic approaches are included in the article, offering guidance for medical professionals in severe, complicated cases of SARS-CoV-2 infection. We can conclude that severe COVID-19 is closely related to vascular inflammation and intense cytokine release leading to hemostasis disorders. Overweight, hyperglycemia, cardiovascular diseases, and old age are important risk factors for severe outcomes of coronavirus infection, involving a hypercoagulable state. Early diagnosis and proper therapy in complicated SARS-CoV-2-infected cases could reduce mortality and the need for intensive care during hospitalization in patients with cardiometabolic comorbidities.

"Multisystem Inflammatory Syndrome in Children" (MIS-C) after COVID-19 Infection in the Metropolitan Area of Nuremberg-Erlangen, Germany-Expectations and Results of a Two-Year Period

BACKGROUND

Multisystemic Inflammatory Syndrome in children (MIS-C) is a rare autoimmune disorder occurring after a latency period following acute SARS-CoV-2 infection. The therapeutic regime of MIS-C is adapted to the therapy of the Kawasaki disease, as clinical symptoms are similar. Since the Kawasaki disease can potentially result in severe symptoms, which may even affect long-term health, it is essential to gain further knowledge about MIS-C. Thus, we aimed to investigate the incidence, symptoms, therapeutical procedure and outcome of MIS-C patients in the metropolitan area of Nuremberg-Erlangen during the SARS-CoV2 pandemic.

MATERIAL AND METHODS

Retrospective analysis of clinical charts of MIS-C patients was carried out at three children's hospitals covering the medical care of the metropolitan area of Nuremberg-Erlangen in Germany. Demographic characteristics and symptoms at first visit, their clinical course, therapeutic regime and outcome were recorded within the time period January 2021-December 2022.

RESULTS

Analysis of 10 patients (5 male, 5 female) with MIS-C resulting in an incidence of 2.14/100.000 children. The median time between COVID-19 infection and admission to hospital was 5 weeks. The median age was 7 years. Symptoms comprised fever (100%), rash (70%), bilateral non-purulent conjunctivitis (70%) and urticaria (20%). At the time of presentation, diagnosis-defining inflammation parameters were increased and the range for C-reactive protein was 4.13 mg/dL to 28 mg/dL, with a median of 24.7 mg/dL. Procalcitonin was initially determined in six patients (1.92 ng/mL to 21.5 ng/mL) with a median value of 5.5 pg/mL. Two patients displayed leukocytosis and two displayed leukopenia. None of the patients presented coronary pathologies. Nine of the ten patients received intravenous immunoglobulin (IVIG) therapy. In addition, patients received intravenous steroids (80%) and acetylsalicylic acid (80%).

CONCLUSION

SARS-CoV virus may rarely exert multiorgan manifestations due to hyperinflammatory immunological processes. Within two years of the COVID-19 pandemic, we identified ten patients with COVID-induced MIS-C in the metropolitan area Nuremberg-Erlangen. In the description of the patient collective, we can confirm that MIS-C is distinguished from the Kawasaki disease by the lack of coronary manifestations. Interestingly, although having monitored all pediatric facilities in the investigated area, we find lower incidences of MIS-C compared to findings in the literature. In conclusion, an overestimation of incidences in the upcoming MIS-C during the pandemic needs to be considered.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Principles of Rational COVID-19 Therapy in Pediatrics

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

Pediatric multisystem inflammatory syndrome associated with COVID-19: Insights in pathogenesis and clinical management

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been a major challenge to be faced in recent years. While adults suffered the highest morbidity and mortality rates of coronavirus disease 2019, children were thought to be exclusively asymptomatic or to present with mild conditions. However, around April 2020, there was an outbreak of a new clinical syndrome related to SARS-CoV-2 in children - multisystemic inflammatory syndrome in children (MIS-C) - which comprises a severe and uncon-trolled hyperinflammatory response with multiorgan involvement. The Centers for Disease Control and Prevention considers a suspected case of MIS-C an individual aged < 21 years presenting with fever, high inflammatory markers levels, and evidence of clinically severe illness, with multisystem (> 2) organ involvement, no alternative plausible diagnoses, and positive for recent SARS-CoV-2 infection. Despite its severity, there are no definitive disease management guidelines for this condition. Conversely, the complex pathogenesis of MIS-C is still not completely understood, although it seems to rely upon immune dysregulation. Hence, in this study, we aim to bring together current evidence regarding the pathogenic mechanisms of MIS-C, clinical picture and management, in order to provide insights for clinical practice and implications for future research directions.

The Impact of Post-COVID-19 Syndrome in Adolescents: A Pilot Study

BACKGROUND

 Post-COVID-19 syndrome has emerged as a long-term complication in adults and children; its effect on adolescents' performance in school is not well studied.

OBJECTIVES

To study the physical/psychological impact of prolonged post-COVID-19 symptoms on school performance.

METHODS

 This is a cross-sectional study using Google Forms, a web-based fully anonymized survey of children in grades 10-12.

RESULTS

 The study included 54 students with a mean age of 16 years of whom 32 had COVID-19. Two were hospitalized and 10 had symptoms lasting more than four weeks. Commonly reported chronic symptoms were fatigue and cough. Seven students quit sports; eight had a decrease in their academic performance. Adolescents being infected more than once or not being fully vaccinated were more likely to develop prolonged symptoms and quit sports while academic performance in school was not affected. Three out of 10 (30%) students who had COVID-19 and responded to the questionnaire reported not seeking help.

CONCLUSION

Post-COVID-19 syndrome is associated with a decline in physical but not mental performance in school. Being infected more than once with SARS-CoV-2 seems to play an important role in the persistence of post-COVID-19 symptoms despite the fact that some adolescents are hesitant to seek medical or psychological care.

Emerging Insights Into the Pathophysiology of Multisystem Inflammatory Syndrome Associated With COVID-19 in Children

Multisystem inflammatory syndrome in children (MIS-C) has emerged as a rare delayed hyperinflammatory response to SARS-CoV-2 infection and causes severe morbidity in the pediatric age group. Although MIS-C shares many clinical similarities to Kawasaki disease (KD), important differences in epidemiologic, clinical, immunologic, and potentially genetic factors exist and suggest potential differences in pathophysiology and points to be explored and explained. Epidemiologic features include male predominance, peak age of 6 to12 years, and specific racial or ethnicity predilections. MIS-C is characterized by fever, prominent gastrointestinal symptoms, mucocutaneous manifestations, respiratory symptoms, and neurologic complaints, and patients often present with shock. Cardiac complications are frequent and include ventricular dysfunction, valvular regurgitation, pericardial effusion, coronary artery dilation and aneurysms, conduction abnormalities, and arrhythmias. Emerging evidence regarding potential immunologic mechanisms suggest that an exaggerated T-cell response to a superantigen on the SARS-CoV-2 spike glycoprotein-as well as the formation of autoantibodies against cardiovascular, gastrointestinal, and endothelial antigens-are major contributors to the inflammatory milieu of MIS-C. Further studies are needed to determine both shared and distinct immunologic pathway(s) that underlie the pathogenesis of MIS-C vs both acute SARS-CoV-2 infection and KD. There is evidence to suggest that the rare risk of more benign mRNA vaccine-associated myopericarditis is outweighed by a reduced risk of more severe MIS-C. In the current review, we synthesize the published literature to describe associated factors and potential mechanisms regarding an increased risk of MIS-C and cardiac complications, provide insights into the underlying immunologic pathophysiology, and define similarities and differences with KD.

Characteristics and outcomes of multisystem inflammatory syndrome in children: A multicenter, retrospective, observational cohort study in Mexico

Introduction

Multisystem inflammatory syndrome in children associated with coronavirus disease 2019 (MIS-C), a novel hyperinflammatory condition secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is associated with severe outcomes such as coronary artery aneurysm and death.

Methods

This multicenter, retrospective, observational cohort study including eight centers in Mexico, aimed to describe the clinical characteristics and outcomes of patients with MIS-C. Patient data were evaluated using latent class analysis (LCA) to categorize patients into three phenotypes: toxic shock syndrome-like (TSSL)-MIS-C, Kawasaki disease-like (KDL)-MIS-C, and nonspecific MIS-C (NS-MIS-C). Risk factors for adverse outcomes were estimated using multilevel mixed-effects logistic regression.

Results

The study included 239 patients with MIS-C, including 61 (26%), 70 (29%), and 108 (45%) patients in the TSSL-MIS-C, KDL-MIS-C, and NS-MIS-C groups, respectively. Fifty-four percent of the patients were admitted to the intensive care unit, and 42%, 78%, and 41% received intravenous immunoglobulin, systemic glucocorticoids, and anticoagulants, respectively. Coronary artery dilatation and aneurysms were found in 5.7% and 13.2% of the patients in whom coronary artery diameter was measured, respectively. Any cause in-hospital mortality was 5.4%. Hospitalization after ten days of symptoms was associated with coronary artery abnormalities (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.2-2.0). Age ≥10 years (OR: 5.6, 95% CI: 1.4-2.04), severe underlying condition (OR: 9.3, 95% CI: 2.8-31.0), platelet count <150,000 /mm³ (OR: 4.2, 95% CI: 1.2-14.7), international normalized ratio >1.2 (OR: 3.8, 95% CI: 1.05-13.9), and serum ferritin concentration >1,500 mg/dl at admission (OR: 52, 95% CI: 5.9-463) were risk factors for death.

Discussion

Mortality in patients with MIS-C was higher than reported in other series, probably because of a high rate of cases with serious underlying diseases.

Incidence and Prevalence of Multisystem Inflammatory Syndrome in Children (MIS-C) in Southern Italy

Multisystem inflammatory syndrome in children (MIS-C) is a pediatric hyperinflammatory syndrome related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection whose epidemiology is not very well known at present. The objective of the study was to better understand the incidence of MIS-C in the Apulia region in southern Italy. Our primary goal was to estimate the incidence of newly identified cases of MIS-C in children aged 0-18 years, during a period of six months, encompassing the second pandemic wave. We also analyzed the characteristics of our cohort in terms of clinical features, treatment, and outcomes. The cumulative incidence of MIS-C was 3.27 per 100,000 residents between 0 and 18 years of age. In our cohort, gastrointestinal, mucocutaneous, and cardiac involvement were the most common clinical features. With our step-up approach to therapy, no patients required intensive care unit (ICU) admission and no cardiac sequelae after 6 months of onset were found in echocardiograms. Conclusion: Our epidemiological study of MIS-C in southern Italy showed unexpectedly overlapping figures with other US studies.

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.

Multisystem inflammatory syndrome in children: A dysregulated autoimmune disorder following COVID-19

Multisystem inflammatory syndrome in children (MIS-C) is a dysregulated autoimmune-mediated illness in genetically susceptible patients following COVID-19 with an interval of 2-6 weeks. The median age of patients with MIS-C is 6-11 years. Most common manifestations are involvement of gastrointestinal tract, cardiovascular system, hematological system, and mucocutaneous system. Respiratory tract, neurological system, musculoskeletal system, and kidney are less frequently affected. Mucocutaneous manifestations and coronary artery abnormalities characteristic for Kawasaki disease (KD) may be observed in a significant proportion of MIS-C patients that may make the differential diagnosis be difficult for some patients, especially in the post-pandemic era. The mortality rate is 1-3%. Management and prognosis of MIS-C are similar to that of KD. MIS-C and KD may share a common pathogenic process. Based on the observation of MIS-C-like illness in uninfected neonates, i.e. multisystem inflammatory syndrome in neonates, both MIS-C and KD may be a consequence of dysregulated, over-exaggerated humoral immune responses triggered by a specific infectious agent.

Misdiagnosis of multisystem inflammatory syndrome in children: A diagnostic challenge

AIMS

As the COVID-19 pandemic continues, multisystem inflammatory syndrome in children (MIS-C) maintains its importance in the differential diagnosis of common febrile diseases. MIS-C should be promptly diagnosed because corticosteroid and/or intravenous immunoglobulin treatment can prevent severe clinical outcomes. In this study, we aimed to evaluate clinical presentation, diagnostic parameters and management of MIS-C and compare its clinical features to those of common febrile disease.

METHODS

This study was conducted at a tertiary-level university hospital between December 2020 and October 2022. One hundred and six children who were initially considered to have MIS-C disease were included in the study. During the follow-up period in the hospital, when the clinical and laboratory findings were re-evaluated, 38 out of 106 children were diagnosed differently. The clinical and laboratory findings of 68 children followed up with the diagnosis of MIS-C and 38 children who were initially misdiagnosed as MIS-C but with different final diagnoses were retrospectively compared.

RESULTS

We identified 68 patients with MIS-C and 38 patients misdiagnosed as MIS-C during the study period. Infectious causes (71%), predominantly bacterial origin, were the most frequently confused conditions with MIS-C. Patients with MIS-C were older and had a more severe clinical course with high rates of respiratory distress, shock, and paediatric intensive care unit admission. While rash and conjunctivitis were more common among patients with MIS-C, cough, abdominal pain and diarrhoea were observed more frequently in patients misdiagnosed as MIS-C. Lower absolute lymphocyte counts, platelet counts and higher C-reactive protein and fibrinogen levels, pathological findings on echocardiography were the distinctive laboratory parameters for MIS-C. Multivariate analysis showed that older age, presence of conjunctivitis, high level of serum CRP and lower platelets were the most discriminative predictors for the diagnosis of MIS-C.

CONCLUSION

There are still no specific findings to diagnose MIS-C, which therefore can be confused with different clinical conditions. Further data are needed to assist the clinician in the differential diagnosis of MIS-C and the diagnostic criteria should be updated over time.

Children's SARS-CoV-2 Infection and Their Vaccination

SARS-CoV-2, a novel coronavirus, causes respiratory tract infections and other complications in affected individuals, and has resulted in numerous deaths worldwide. The unprecedented pace of its transmission worldwide, and the resultant heavy burden on healthcare systems everywhere, prompted efforts to have effective therapeutic strategies and vaccination candidates available to the global population. While aged and immunocompromised individuals form a high-risk group for COVID-19 and have severe disease outcome, the rate of infections among children has also increased with the emergence of the Omicron variant. In addition, recent reports of threatening SARS-CoV-2-associated complications in children have brought to the forefront an urgent necessity for vaccination. In this article, we discuss the current scenario of SARS-CoV-2 infections in children with a special focus on the differences in their immune system response as compared to adults. Further, we describe the various available COVID-19 vaccines, including the recent bivalent vaccines for children, in detail, intending to increase willingness for their acceptance.

Multi-inflammatory syndrome in children (MIS-C) associated with COVID-19: a nursing perspective experience report from a high-income tertiary paediatric hospital context

BACKGROUND

In the midst of the COVID-19 coronavirus pandemic, a new disease that affects children has arisen called multisystem inflammatory syndrome in children (MIS-C). Several research articles focusing on its medical aspects have been published, but very few have focused on nursing care. The aim of this study was therefore to describe the nursing status of children suffering from MIS-C and the experiences of registered nurses (RNs) in caring for these children in paediatric hospital inpatient care.

METHODS

The study design includes both quantitative nursing clinical record data and qualitative interview data. Quantitative data from the clinical records were analysed using descriptive statistics. Qualitative data analysis of the interviews was conducted using both deductive and inductive approaches with content analysis.

RESULTS

In total, 47 clinical records from children with MIS-C were investigated during January-March 2021. The mean age of the children was 8.8 years. Boys were more affected than girls. Challenges in children's nursing status were related to circulation (fever and swelling), nutrition (great thirst and loss of appetite), pain, and psychosocial situations. When caring for children with MIS-C, nurses experienced "frustration over uncertainty of care", "children's illbeing" and "unavoidable procedures".

CONCLUSION

This study contributes knowledge to the ongoing nursing care of children suffering from MIS-C. The results show many different areas of nursing focus, which challenges nurses and other disciplines within paediatric hospital care. One important factor when caring for these children was the use of a central venous line early in the care process, which improved the quality of care. Moreover, the care of children suffering from MIS-C demands resources and time from healthcare professionals, especially RNs, to meet caring needs and reduce illbeing.

The role of indices in predicting disease severity and outcomes of multisystem inflammatory syndrome in children

BACKGROUND

The aim of this study was to evaluate the role of the systemic immune inflammation index (SII), C-reactive protein/albumin ratio (CAR), the monocyte/lymphocyte ratio (MLR), and the neutrophil/lymphocyte ratio (NLR) in predicting disease severity, treatment, and prognosis in multisystem inflammatory syndrome in children (MIS-C).

METHODS

This medical record review retrospectively evaluated the clinical and laboratory findings of 191 MIS-C patients followed in the Department of Pediatric Rheumatology at Ankara City Hospital, Turkey. The patients were grouped by disease severity: mild, moderate, and severe. SII, CAR, MLR, and NLR were calculated for each group.

RESULTS

All patients had fever at the time of admission; 153 (80.1%) had gastrointestinal tract involvement, 74 (38.7%) had rash, 63 (33%) had conjunctivitis, 107 (56%) had cardiac involvement, 32 (15.6%) had renal involvement, and 143 (74.9%) had hematological involvement. According to logistic regression analysis, SII, NLR, MLR, and CAR were found to be predictive indexes for disease severity, need for intensive care, need for inotropes, and anakinra treatment in MIS-C. The cut-off values of ≥1605.3 for SII, ≥9.1 for NLR, and ≥3.9 for CAR increased the risk of severe disease by 3.4, 7.1, and 5.7 times, respectively.

CONCLUSION

NLR, SII, MLR, and CAR are effective and useful for predicting the severity of MIS-C, the need for intensive care, and the need for anakinra treatment.

Neurological consequences of SARS-CoV-2 infections in the pediatric population

COVID-19 in the pediatric population is mostly asymptomatic. However, 1 out of 5 children presents non-specific neurologic symptoms such as headache, weakness, or myalgia. Furthermore, rarer forms of neurological diseases are increasingly being described in association to a SARS-CoV-2 infection. Encephalitis, stroke, cranial nerves impairment, Guillain-Barré syndrome or acute transverse myelitis have been reported and account for around 1% of pediatric COVID-19 cases. Some of these pathologies may occur during or after the SARS-CoV-2 infection. The pathophysiological mechanisms range from direct invasion of the central nervous system (CNS) by SARS-CoV-2 itself to postinfectious immune-mediated CNS inflammation. In most cases, patients presenting neurological pathologies related to SARS-CoV-2 infection are at greater risk of life-threatening complications and should be closely monitored. Further studies are needed to acknowledge the potential long-term neurodevelopmental consequences of the infection.

Hemolytic uremic syndrome in the setting of COVID-19 successfully treated with complement inhibition therapy: An instructive case report of a previously healthy toddler and review of literature

INTRODUCTION

As the global pandemic continues, new complications of COVID-19 in pediatric population have turned up, one of them being hemolytic uremic syndrome (HUS), a complement-mediated thrombotic microangiopathy (CM-TMA) characterized by triad of thrombocytopenia, microangiopathic hemolytic anemia and acute kidney injury (AKI). With both multisystem inflammatory syndrome in children (MIS-C) and HUS sharing complement dysregulation as one of the key factors, the aim of this case report is to highlight differences between these two conditions and also emphasize the importance of complement blockade as a treatment modality.

CASE REPORT

We describe a 21-month-old toddler who initially presented with fever and confirmed COVID-19. His condition quickly deteriorated and he developed oliguria, accompanied with diarrhea, vomiting and oral intake intolerance. HUS was suspected, supported with compelling laboratory findings, including decreased platelets count and C3 levels, elevated LDH, urea, serum creatinine and sC5b-9 and presence of schistocytes in peripheral blood, negative fecal Shiga toxin and normal ADAMTS13 metalloprotease activity. The patient was given C5 complement blocker Ravulizumab and started to display rapid improvement.

CONCLUSION

Although reports of HUS in the setting of COVID-19 continue to pour in, the questions of exact mechanism and similarities to MIS-C remain. Our case for the first time accentuates the use of complement blockade as a valuable treatment option in this scenario. We sincerely believe that reporting on HUS as a complication of COVID-19 in children will give rise to improved diagnosis and treatment, as well as better understanding of both of these intricating diseases.