Immune System Development Processes with Special Emphasis on Relationship to Potential Mechanisms of MIS-C

Development of the mammalian immune system requires the intersection of myriad internal and external signals, from the migration of pluripotent stem cells to interactions with the vaginal microbiome during partuition to environmental factors that shape immune processes throughout life. Because the sequence of immune developmental events is fairly transcripted across time, multiple windows of susceptibility exist that can lead to immune dysfunction when these developmental events are perturbed. Additionally, early-life immune dysfunction can persist, leading to increased disease risk across the lifespan. Immune dysfunction can present functionally as suppression, hyperresponsivity, or inappropriate inflammation and molecularly, may involve multiple cells and signaling pathways. Thus, scenarios that lead to multisystem inflammatory syndrome in children (MIS-C) can be complex and multifaceted. This presentation will consider windows of susceptibility as well as external factors that may increase the risk of MIS-C.

Fulminant varicella infection complicated by disseminated intravascular coagulation following influenza-A case report

Objectives: Varicella is common infectious disease mainly in childhood, usually is a mild, self-limited illness and complications are usually rare. The incubation period for this disease is generally 14- 16 days but may vary from 7 to 21 days. Varicella in the adults with comorbidities or immunosuppressed children may be severe and prolonged with complications. Method(s): A case report of a 6-year-old girl hospitalized for new-onset manifestations of disseminated vesicular exanthema, the manifestations of which occurred mainly on the chest, back, capillitium, oral cavity, and genital area. The child was suffering from abdominal, knee and lumbosacral pain at that time. The patient's history revealed that 10 days prior to the cutaneous manifestations, she had influenza with bronchopneumonia requiring oxygen therapy, steroids and antibiotics. Result(s): The condition progressed within 48 h, complicated by the development of multi-organ failure, coagulopathy with the development of disseminated intravascular coagulopathy over the course of antiviral, antibiotic and antifungal therapy. Laboratory parameters included high elevation of C-reactive protein, il-6, leukocytosis, neutrophilia and highly elevated liver enzymes. Varicella infection was confirmed by detection of herpes zoster virus - polymerase chain reaction (PCR) from vesicles. The patient received intravenous immunoglobulin therapy at a dose of 2 g/L and fresh frozen plasma, thrombocyte concentrate. The girl was intubated with analogization. Laboratory parameters subsequently revealed high anti CoV-2 positivity, high CoV-2 IgG positivity and negative CoV-2 IgM. The patient's condition did not preclude the course of multisystem inflammatory syndrome in children (MIS-C) corticosteroids were added to the treatment at a dose of 1 mg/kg weight. Patient's condition stabilized after 1 month. Discussion(s): Our case report presents an example of fulminant complicated life-threatening course of varicella. Even in common respiratory infections, we must think about the risk and consequences of coinfections and post-infectious complications such as in our case especially influenza and COVID-19.

SARS-COV-2 Infection in Children and Young People in Bulgaria - A Prospective, Single-Center, Cohort Study

Compared to other respiratory viruses, the proportion of hospitalizations due to SARS-CoV-2 among children is relatively low. While severe illness is not common among children and young individuals, a particular type of severe condition called multisystem inflammatory syndrome in children (MIS-C) has been reported. The aim of this prospective cohort study, which followed a group of individuals under the age of 19, was to examine the characteristics of patients who had contracted SARS-CoV-2, including their coexisting medical conditions, clinical symptoms, laboratory findings, and outcomes. The study also aimed to investigate the features of children who met the WHO case definition of MIS-C, as well as those who required intensive care. A total of 270 patients were included between March 2020 and December 2021. The eligible criteria were individuals between 0-18 with a confirmed SARS-CoV-2 infection at the Infectious Disease Hospital "Prof. Ivan Kirov"in Sofia, Bulgaria. Nearly 76% of the patients were <= 12 years old. In our study, at least one comorbidity was reported in 28.1% of the cases, with obesity being the most common one (8.9%). Less than 5% of children were transferred to an intensive care unit. We observed a statistically significant difference in the age groups, with children between 5 and 12 years old having a higher likelihood of requiring intensive care compared to other age groups. The median values of PaO2 and SatO2 were higher among patients admitted to the standard ward, while the values of granulocytes and C-reactive protein were higher among those transferred to the intensive care unit. Additionally, we identified 26 children who met the WHO case definition for MIS-C. Our study data supports the evidence of milder COVID-19 in children and young individuals as compared to adults. Older age groups were associated with higher incidence of both MIS-C and ICU admissions.Copyright © 2023 P. Velikov et al., published by Sciendo.

Factors affecting disease severity of multisystem inflammatory syndrome in children

Purpose: Multisystem inflammatory syndrome that occurs after SARS-Cov-2 infection with fever, cardiogenic shock and hyperinflammation in children, can be life threatening. In this study, it was aimed to investigate the effects of the complaint and duration at diagnosis on the severity of multisystem inflammatory syndrome in children. Materials and methods: The medical records of 99 pediatric patients, who were diagnosed multisystem inflammatory syndrome between September 2020 and August 2021 according to Centers for Disease Control and Prevention, were evaluated retrospectively. Demographic features, initial findings, and admission time of patients were noted. Patients were categorized according to intensive care necessity. Results: The median age of the patients was 10 (2-18) and 62 (62.6%) of patients were male. The median duration before admission was 4 (1-10) days. All patients has fever, 81.8% had gastrointestinal and 75.8% had cardiovascular involvement at admission. The patients (56.6%) who were accepted as severe and moderate MIS-C required intensive care. Prolonged fever, delayed admission, cardiovascular involvement, high inflammatory markers, lymphopenia and thrombocytopenia were found to key parameters determining the need for intensive care. Conclusion: Multisystem inflammatory syndrome in children is a new disease characterized by fever, signs of inflammation and organ dysfunction associated with SARS-CoV-2 infection. Delayed admission, high cardiac and inflammatory markers at diagnosis increase the need for intensive care. © 2022, Pamukkale University. All rights reserved.

Bilateral Spontaneous Pneumothorax in a Child with Multisystem Inflammatory Syndrome Associated with COVID-19

Introduction: Spontaneous pneumothorax is a rare complication of coronavirus disease 2019 (COVID-19), primarily reported in adults. Pediatric cases with bilateral pneumothorax are much less reported. Case Presentation: We presented the case of a five-year-old previously healthy boy who developed persistent fever, abdominal pain, generalized maculopapular rash, and dyspnea before admission. His chest computed tomography (CT) showed a viral involvement pattern of pneumonia suggestive of COVID-19. Subsequently, he was confirmed with multisystem inflammatory syndrome in children (MIS-C). While he responded well to the therapies, on the fifth day of admission, he developed respiratory distress again. A chest roentgenogram showed bilateral spontaneous pneumothorax. Bilateral chest tubes were inserted, and his condition improved sig-nificantly after five days of admission to the intensive care unit. Two weeks later, he was discharged in good condition. Conclusion(s): Children with MIS-C associated with COVID-19 may develop primary spontaneous pneumothorax. Owing to the clinical picture overlapping with MIS-C associated with COVID-19, the timely diagnosis of pneumothorax may be challenging in such patients.Copyright © 2022, Author(s).

Recurrence of multisystem inflammatory syndrome associated with Covid-19 infection: case report.

The COVID-19 pandemic has left millions of cases and deaths worldwide, in children the infection is less severe and has low mortality. A post-infectious entity called Systemic Multiinflammatory Syndrome (MIS-C) associated with COVID-19 infection is described, which has a mortality rate ten times higher than acute infection in children. MIS-C is characterized by sustained systemic inflammatory manifestations associated with fever and multiple system involvement. We present the case of a schoolgirl who presented a diagnosis of MIS-C with a good response to management and 11 months later, she presented a second episode that also responded to treatment. To date, we have not found in the literature the report of recurrence of MIS-C in children, such as the case presented by us, it marks an important precedent, inviting us to consider recurrence as a possibility in the case of a similar clinical presentation.Copyright © 2023 Asociacion Colombiana de Infectologia. All rights reserved.

Multisystem Inflammatory Syndrome in Children: Characteristics and Epidemiology

Shortly after the novel coronavirus (now known as SARSCoV- 2) was recognized, data began to accumulate on the virus's effects on children. Initial data showed that children were more likely to be mildly affected, compared to adults, with lower risks of hospitalization and death. However, in April of 2020, reports appeared of a severe disease in children occurring about two-six weeks after infection with SARS-CoV-2. The features were similar to those seen in a rare vasculitis condition called Kawasaki disease. On May 14, 2020, the Centers for Disease Control and Prevention (CDC) issued a national health advisory regarding this new condition, which was called multisystem inflammatory syndrome in children (MIS-C). The current case definition for MIS-C includes six criteria: (1) serious illness leading to hospitalization or resulting in death;(2) age less than 21 years;(3) measured fever over 38 degrees Celsius or report of subjective fever;(4) laboratory evidence of inflammation;(5) new onset involvement in at least two of the following (cardiac involvement, mucocutaneous involvement, shock, gastrointestinal involvement, and hematologic involvement);and (6) laboratory-confirmed SARS-CoV-2 infection or an epidemiologic link to a person with COVID-19. According to CDC, as of January 3, 2023, there have been 9,333 patients in the United States meeting the case definition of MIS-C, with 76 deaths. The median age of patients was nine years, with half of those affected between the ages of five and 13 years. More than half of the reported patients on whom race-ethnicity information was available were in children who are Hispanic/Latino or Black, non-Hispanic. Over 60% of reported patients were male. Most affected children had previously been healthy. A better understanding of the pathogenesis of this serious illness is needed to provide better treatment options for children with MIS-C. Prevention of MIS-C is focused on the prevention of SARS-CoV-2 infection through staying up to date with COVID-19 vaccination, masking, and other prevention strategies.

EBV-related lymphoproliferative disease in Wiskott-Aldrich Syndrome patient

Case: Wiskott-Aldrich Syndrome (WAS) is a rare X-linked inborn error of immunity caused by mutations in the WAS gene. It is classically characterized by immunodeficiency, eczema, and micro-thrombocytopenia. It has been known since the 1960s that patients with WAS have an increased risk of lymphoproliferative disease though the exact incidence remains unknown in the American population. Limited case reports have discussed EBV-related lymphoproliferative disease in patients with WAS. We present a case of a 9-year-old boy with known WAS complicated by eczematous rash, thrombocytopenia, recurrent ear infections, and monoclonal gammopathy who was found to have submandibular EBV-associated lymphoid hyperplasia with associated lung and retroperitoneal lymphadenopathy. Family had been offered treatment with hematopoietic stem cell transplant but declined multiple times in the past. Earlier in the year, he presented with possible MIS-C with negative SARS-CoV-2 PCR. He presented to our hospital with mastoiditis and lymphadenopathy. Physical examination showed severe eczema on hands and tender right mastoid. Laboratory evaluation showed thrombocytopenia, elevated IgG of 6290, IgA of 744, IgE of 827, low IgM of 41, and 14% response to pneumococcal titers. He was empirically treated with intravenous antibiotics. ENT performed right postauricular incision and drainage and the culture grew Hemophilus influenza. Throughout his hospital stay, his submandibular lymphadenopathy became more prominent despite treatment. Core needle biopsy of right submandibular lymph node was suggestive of EBV-associated lymphoid hyperplasia. EBV PCR and antibodies were both positive. CT chest, abdomen, and pelvis revealed multifocal pulmonary lymphadenopathy and a diffuse, bilateral nodularity as well as retroperitoneal and mesenteric lymphadenopathy. He was given four doses of weekly Rituximab, which successfully decreased EBV viremia below linear detectability. Immunoglobulin replacement therapy (IgRT) was initiated. Bronchoalveolar lavage and lung biopsy were performed and are results are currently pending. Discussion(s): We present a case of a 9-year-old boy with known WAS awaiting transplant who was found to have submandibular EBV-associated lymphoid hyperplasia with associated lung and retroperitoneal lymphadenopathy. While lymphoproliferative disease is a known complication of WAS, EBV-related lymphoproliferative disease in WAS patients has only been reported as case reports and remains a rare but known complication of patient with WAS.Copyright © 2023 Elsevier Inc.

Should Young Covid-19 Patients be Suplemented with Vitamin D?

It is well known that vitamin D's general immunomodulatory actions are helpful in viral infections and that a shortage is linked to a more serious prognosis for Covid-19. In this sistematic review, we examined the existing literature on evidence as to whether there is also link between vitamin D range levels in pediatric population and the outcome of the Covid-19 infection. We looked for studies that measured vitamin D blood concentrations and examined the effects of vitamin D supplementation in young infected patients. Vitamin D may decrease the risk of respiratory infections in a number of ways through its interactions with numerous cells, including by decreasing viral survival and replication, reducing the cytokine storm, raising angiotensin-converting enzyme 2 concentrations (ACE2) while not damaging the endothelial integrity. The incidence or severity of Covid-19 is linked with blood 25-hydroxyvitamin D concentrations, according to many observational studies. However experimental verification is still needed. Given their safety and broad therapeutic window, vitamin D supplements seem to be an effective way for individuals and doctors to prevent or treat Covid-19. Nonetheless, the outcomes of significant vitamin D randomized controlled trials are further needed.Copyright © 2022 Maria Nicolae et al., published by Sciendo.

Prevention and Treatment of Multisystem Inflammatory Syndrome in Children

We will review the intersection of COVID-19 and children, including acute COVID-19, long COVID, and multisystem inflammatory syndrome in children (MIS-C) based on our local experiences. We will review available local epidemiologic COVID-19 data in pediatrics that has led our MIS-C team's prevention and treatment strategy. We will review the recommended treatments for pediatric acute COVID-19 and MIS-C in children, and evidence-based prevention strategies and walk through our experiences in implementing these prevention and treatment strategies.

Pediatric Inflammatory Multisystem Syndrome Temporally Associated with Sars-Cov-2 Infection

Despite the low incidence, low mortality and relatively mild symptoms of COVID-19 in children, there has been a rise in pediatric patients who develop a condition resembling Kawasaki disease after COVID-19 or contact with individuals infected with SARS-CoV-2. This condition is known as the pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 infection (PIMS-TS). This review introduces the reader to the hypotheses of PIMS-TS pathogenesis, provides information about its diagnosis and treatment, presents clinical and laboratory data and describes treatments strategies used in children and adolescents hospitalized to the intensive care unit of the Pediatric Research and Clinical Center for Infectious Diseases. Besides, the review outlines the main diagnostic and prognostic challenges of PIMS-TS.Copyright © Extreme Medicine.All right reserved.

Inherited deficiency of the OAS-RNase L pathway in children with MIS-C

Multisystem inflammatory syndrome in children (MIS-C) is a rare and severe condition that follows benign COVID-19. We report autosomal recessive deficiencies of OAS1, OAS2, or RNASEL in five unrelated children with MIS-C. The cytosolic dsRNA-sensing OAS1 and OAS2 generate 2'-5'-linked oligoadenylates (2-5A) that activate the ssRNA-degrading RNase L. Consistent with the absence of pneumonia in these patients, epithelial cells and fibroblasts defective for this pathway restricted SARS-CoV-2 normally. This contrasted with IFNAR1-deficient cells from patients prone to hypoxemic pneumonia without MIS-C. Monocytic cell lines and primary myeloid cells with OAS1, OAS2, or RNASEL deficiencies produce excessive amounts of inflammatory cytokines upon dsRNA or SARS-CoV- 2 stimulation. Exogenous 2-5A suppresses cytokine production in OAS1-but not RNase L- deficient cells. Cytokine production in RNase L-deficient cells is impaired by MDA5 or RIG-I deficiency and abolished by MAVS deficiency. Recessive OAS-RNase L deficiencies in these patients unleash the production of SARS-CoV-2-triggered, MAVS-mediated inflammatory cytokines by mononuclear phagocytes, thereby underlying MIS-C.Copyright © 2023 Elsevier Inc.

Once again about the new coronavirus infection COVID-19.

The COVID-19 pandemic continues to affect millions of people with increasing morbidity and mortality. Substantial variations exists in drug treatment of COVID-19. Extracorporeal membrane oxygenation (ECMO) facilitates survival of select critically ill patients with COVID-19 with about 25-45% survival rate;survivors tend to be younger and have a shorter duration from diagnosis to cannulation. The practioners found the severe complications including concomitant neurological manifestations (from headache, anosmia, ageusia to encephalopathy, stroke and others) and multisystem inflammation syndrome (MIS) predominantly in children few weeks after SARS-CoV-2 infection and characterized by persistent fever, vomiting, headache, Kawasaki - like rash and fatigue. Regarding MIS the authors did not find strong association between the complications rate and outcomes and regime of immunomodulation treatment. The neurological manifestations in pts with COVID-19 were associated with higher in-hospital mortality.Copyright © 2022 Sinergia Press. All rights reserved.

MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN ACROSS 16 LATIN AMERICAN COUNTRIES: A MULTICENTER STUDY FROM THE REKAMLATINA NETWORK

BackgroundMultisystem Inflammatory Syndrome in Children (MIS-C) is one of the most feared complications following SARS-CoV2 infection in children and adolescents. Few multinational multicenter studies from Latin America have been published.ObjectivesTo describe the clinical presentation, management, and outcomes of MIS-C in Latin America.MethodsObservational, prospective and retrospective, multicenter study to gather information from 84 participating centers across 16 Latin American countries, between August January 1, 2020 and June 30, 2022.ResultsOf the 1,239 reported cases of MIS-C, 84.2% were previously healthy. The most frequent clinical manifestation in our studied population was abdominal pain (N=804, 64.9%), followed by conjunctival injection (N=784, 63.3%). The median days of fever at the time of hospital admission was 5 and a significant number of subjects required admission to an intensive care unit (N=589, 47.8%). A total of 538 (47.2%) patients had an abnormal initial echocardiogram. Most of the subjects (N= 1,096, 88.7%) were treated with intravenous immunoglobulin (IVIG), while 76.7% (N= 947) were treated with steroids, of which 10.6% (N= 100) did not receive IVIG. The death rate attributed to MIS-C was 4.88%, with a rate of 3.39% for those initially diagnosed with MIS-C and 8.85% for those whose admission diagnosis was not MIS-C (P= 0.00001).ConclusionOne of the most significant findings from our study was the death rate, especially in those not initially diagnosed with MIS-C, in whom it was higher. This highlights the importance of increasing awareness and making an earlier diagnosis of MIS-C in Latin America.REFERENCES:NIL.Acknowledgements:NIL.Disclosure of InterestsNone Declared.

A CLINICAL CASE OF MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN ASSOCIATED WITH A NEW CORONAVIRUS INFECTION (COVID-19).

The article presents a clinical case of diagnosis and treatment of children's multisystem inflammatory syndrome associated with a new coronavirus infection (COVID-19) in a 12-year-old girl. The clinical picture, the dynamics of the disease, the results of instrumental and laboratory findings and successful treatment of the patient are described.Copyright © 2022 Stavropol State Medical University. All rights reserved.

ECMO in acute fulminant myocarditis in pediatrics

Objectives: To describe our experience in ECMO for acute myocarditis Methods: Descriptive, retrospective study (2018-2022) of a cohort of 8 patients < 16 years with acute myocarditis who were assisted on ECMO. Result(s): 8 patients were collected, (6 females), with a mean age 7;8 years [range 0;1-13;8]. In 7/8, the reason for cannulation was hemodynamic instability refractory to medical treatment, with a mean inotropic score of 70 [range 10-122]. Sixty-two percent presented cardiorespiratory arrest prior to cannulation and 2 of them needed ECRP. The mean precannulation troponin level was 1498 ng/ml [range 89-6212]. Primary transport was performed in 4 patients. ECMO was peripheral veno-arterial in 100%, jugulo-carotid in 2/8 and femoro-femoral in 6/8. All patients underwent atrioseptostomy. They received treatment with levosimendan, immunoglobulins, corticoids and carnitine. In 4 acute infectious etiology was confirmed (parvovirus, influenza and SARSCoV2), another one was due to PIMS-TS and in 3 no etiology was found. Six patients underwent myocardial biopsy and 5 of them showed inflammatory infiltrates. The mean time on ECMO was 8 days [range 3-14], 2 of them requiring 2 ECMO courses. The mean length of PICU stay was 21 days [range 10-50]. Two were transferred to a heart transplant center. The main complications were arterial hypertension (88%), bleeding (63%), neurological (50%), arrhythmias (38%), coagulopathy (38%) and infectious (38%). One patient required renal replacement therapy. 1 patient died, 2 had moderate neurological sequels. Conclusion(s): ECMO is a therapeutic option in patients with fulminant myocarditis refractory to medical treatment and may help improve their prognosis.

SINGLE CELL MULTIOMIC PROFILING OF DISRUPTED REGULATORY NETWORKS IN COVID19 ASSOCIATED MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN

BackgroundChildren infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) usually present minimal symptoms or are asymptomatic. Nevertheless, a subset of children 2-6 weeks after the initial SARS-CoV-2 infection develops a postinfectious SARS-CoV-2-related multisystem inflammatory syndrome in (MIS-C). Recently, transient expansion of TRBV11-2 T cell clonotypes in MIS-C was associated with signatures of inflammation and T cell activation, however, the underlying pathophysiology of MIS-C is not fully understood [1].ObjectivesThe purpose of our project is to characterize the complexity of cell populations and capture cellular heterogeneity to uncover the regulatory networks and interactions that are disrupted during MIS-C flare with simultaneous profiling of gene expression and open chromatin regions from the same nuclei.MethodsSamples of peripheral blood mononuclear cells from patients with MIS-C diagnosed at the University Children's Hospital, University Medical Center Ljubljana, were collected during the initial presentation before any treatment and at 6-12 months in remission. The primary aim is to identify which regulatory networks are driving inflammation in MIS-C flare, for which we are performing single cell Multiome ATAC + Gene Expression Sequencing. To enable simultaneous profiling of epigenomic landscape and gene expression from the same nuclei, we are using Chromium Next GEM Single Cell Multiome ATAC + Gene Expression kit from 10X Genomics.ResultsWe included 32 patients with MIS-C from whom we collected paired blood samples during the initial presentation before treatment and at 6-12 months in remission. In single cell multiomic experiment we included 10 patients with paired samples, with the most viable cell count prior cryopreservation. All samples that are included into multiomic single cell analysis have 75% - 99% viability prior cryopreservation. In the protocol the key is to remove remaining granulocytes causing high mitochondrial RNA burden and extensively optimize the dilution factor of lysis buffer and the length of cell lysis step in order to get intact nuclei with no significant blebbing. Afterward, the single cell ATAC libraries as well as single-cell gene expression libraries are constructed and sequenced. Data are undergoing pairwise analysis to compare the cell population heterogeneity, expression profile and open chromatin landscape in the time of the initial presentation of MIS-C and in the remission, with Cell ranger software as well as with R package scREG [2], and custom scripting. In the second step we will inspect if the resulting altered transcriptomic signature from single-cell experiment is present on larger cohort. In that regard, we will perform bulk transcriptomic profiling on all paired collected samples during the initial presentation of MIS-C before treatment and at 6-12 months in remission.ConclusionThe results of this project are expected to enlighten the underlying pathophysiology of MIS-C flare and thus support clinical decision on more targeted treatment. The identified disrupted networks during MIS-C flare could lead the way to establish an early diagnosis and improve long-term outcome, including prevention of myocardial and neuropsychological impairment. Moreover, a better understanding of the disrupted regulatory networks that are driving inflammation in MIS-C, could lead to new insights into diseases with similar clinical presentations as is Kawasaki Disease.References[1]Sacco, K., Castagnoli, R., Vakkilainen, S. et al. Immunopathological signatures in multisystem inflammatory syndrome in children and pediatric COVID-19. Nat Med 28, 1050–1062 (2022).[2]Duren, Z., Chang, F., Naqing, F. et al. Regulatory analysis of single cell multiome gene expression and chromatin accessibility data with scREG. Genome Biol 23, 114 (2022).AcknowledgementsThis research was supported by Slovenian research agency grant J3-3061 and Interreg ITA-SLO project Cattedra.Disclosure of InterestsNone Declared.

Clinical characteristics of children with multisystemic inflammatory syndrome associated with COVID-19 Clinical characteristics of MIS-C associated with COVID-19

Aim: Coronavirus disease 2019 (COVID-19) has become a public health threat to people all over the world in 2020 and 2021. The Centers for Disease Control and Prevention (CDC) and WHO (World Health Organization) have named a novel disease multisystem inflammatory syndrome in children (MIS-C). Herein we aimed to present a group of pediatric patients with MIS-C, who were followed up in our clinic. Material(s) and Method(s): We retrospectively reviewed the medical records of patients who were followed up at our University Hospital with the diagnosis of MIS-C between January 2021 and May 2021. Result(s): The mean age of 9 patients was 87.4 +/-17.8 years (range 6-161 months);six of the patients were male. All patients had fever at admission. The duration of the fever was between 3 and 7 days. Four patients (44.4%) had terminal ileitis on ultrasonic examination. The laboratory tests of the patients revealed leukocytosis in 4 (44.4%) patients, anemia in 5 (55.5%) patients, thrombocytopenia in 1 (11.1%) patient, and a high CRP level in 8 (88.8%) patients. All patients had high sedimentation rates and procalcitonin levels. One (11.1%) patient was operated on for terminal ileitis. All patients were treated with steroids (1-2 mg/kg prednisolone) and IVIG (2gr/kg). Patients who needed ICU admission were also treated with vasoactive drug infusion (intravenous dopamine). Discussion(s): There is a need for increased awareness among pediatricians that MIS-C should come to mind, especially in patients with long-lasting fever and signs and symptoms that resemble Kawasaki disease.Copyright © 2022, Derman Medical Publishing. All rights reserved.