Multisystem inflammatory syndrome in children during the COVID-19 pandemic in Turkey: first report from the Eastern Mediterranean

COVID-19 infection in children with blood cancer: A systematic review

BACKGROUND

Blood cancer is the most common type of cancer and the leading cause of death by disease past infancy among children. Children with blood cancer are vulnerable population to viral infections such as coronavirus disease 2019 (COVID-19).

OBJECTIVES

To estimate the incidence of COVID-19 in children with blood cancer and analyse the demographic parameters, clinical characteristics and treatment outcomes in children with blood cancer with COVID-19 illness.

METHODS

We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline and searched ProQuest, Medline, Embase, PubMed, CINAHL, Wiley online library, Scopus and Nature for studies on the development of COVID-19 in children with blood cancer, published from December 1, 2019 to April 30, 2023, with English language restriction.

RESULTS

Of the 3077 papers that were identified, 155 articles were included in the systematic review (83 case report, 54 cohort and 18 case-series studies). Studies involving 1289 children with blood cancer with confirmed COVID-19 were analysed. Leukaemias (1141 cases) were the most frequent types of blood cancer observed in children who developed COVID-19, followed by non-Hodgkin's lymphomas (59 cases), Hodgkin's lymphomas (36 cases), Langerhans cell histiocytosis (7 cases), myelodysplastic syndrome (7 cases) and myeloid neoplasm (1 case). Among all 1289 blood cancer paediatric cases who transmitted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), some children were documented to be admitted to the intensive care unit (ICU) (n = 175, 13.6%), intubated and placed on mechanical ventilation (MV) (n = 111, 8.6%), suffered acute respiratory distress syndrome (ARDS) (n = 144, 11.2%) or died (n = 111, 8.6%). Overall, COVID-19 in children with different types of blood cancer resulted in no or low severity of disease in 78.6% of all included cases (COVID-19 severity: asymptomatic = 238, mild = 601, or moderate = 171). Treatment for COVID-19 was not necessary in a small number of children with blood cancer (n = 94, 7.3%). Fatality in children with blood cancer with COVID-19 was reported in any of the included blood cancer categories for leukaemias (n = 99/1141, 8.7%), non-Hodgkin's lymphomas (n = 7/59, 11.9%), Hodgkin's lymphomas (n = 2/36, 5.5%), myelodysplastic syndrome (n = 1/7, 14.3%) or myeloid neoplasm (n = 1/1, 100%). Fatality rate in children with blood cancer infected with SARS-CoV-2 was the highest in patients with Hispanic ethnicity (n = 44/111, 39.6%) and COVID-19-related fatality was highest in male patients (76.5% of deceased patients). Most studies reported to alter the intensity and regimen of anticancer treatment in children with blood cancer during course of SARS-CoV-2 infection, however, many studies have reported to successfully treat COVID-19 without any changes to the anticancer treatment.

CONCLUSION

Globally, leukaemias were the most prevalent and myeloid neoplasms were the least prevalent blood cancer types in children who developed SARS-CoV-2 infection. Children with blood cancer infected with SARS-CoV-2 may experience higher rates of ICU admission and mortality in comparison with the healthy pediatric populations. Mortality in children with blood cancer and infected with SARS-CoV-2 was highest in cases belonging to male gender and Hispanic ethnicity. However, children with blood cancer tend to have milder COVID-19 symptoms and are less likely to be hospitalized and have better prognosis when compared to adults. Continuation of anticancer treatment in individual paediatric blood cancer patients with COVID-19 seems to be possible.

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 and cardiac complications: Myocarditis and multisystem inflammatory syndrome in children

Coronavirus is an important pathogen causing disease in humans and animals. At the end of 2019, an investigation into an increase in pneumonia cases in Wuhan, Hubei Province, China, found that the cause was a new coronavirus. This disease, which spread rapidly across China and caused an outbreak worldwide, resulted in a pandemic. Although this virus has previously been referred to as 2019-nCoV, which causes coronavirus disease 2019 (COVID-19), later it was named severe acute respiratory syndrome coronavirus 2. Children were usually asymptomatic and rarely severely affected. In April 2020, reports from the United Kingdom indicated that children may have Kawasaki disease or a clinical condition similar to toxic shock syndrome. This clinical picture was later defined as multisystem inflammatory syndrome in children. Since then, similarly affected children as well as cases with other cardiac complications have been reported in other parts of the world. In this review, we aimed to evaluate COVID-19 in terms of cardiac involvement by reviewing the literature.

NT-proBNP cardiac value in COVID-19: a focus on the paediatric population

NT-proBNP is a peptide related to brain natriuretic peptide, a cardiac biomarker and a member of the natriuretic family of peptides. NT-proBNP has demonstrated its clinical utility in the assessment of a wide spectrum of cardiac manifestations. It is also considered a more precise diagnostic and prognostic cardiac biomarker than brain natriuretic peptide. With the appearance of the Severe Acute Respiratory Syndrome Coronavirus 2 virus and the subsequent COVID-19 pandemic, diagnosis of heart implications began to pose an increasing struggle for the physician. Echocardiography is considered a central means of evaluating cardiac disorders like heart failure, and it is considered a reliable method. However, other diagnostic methods are currently being explored, one of which involves the assessment of NT-proBNP levels. In the literature that involves the adult population, significant positive correlations were drawn between the levels of NT-proBNP and COVID-19 outcomes such as high severity and fatality. In the paediatric population, however, the literature is scarce, and most of the investigations assess NT-proBNP in the context of Multiple Inflammatory Syndrome in Children, where studies have shown that cohorts with this syndrome had elevated levels of NT-proBNP when compared to non-syndromic cohorts. Thus, more large-scale studies on existing COVID-19 data should be carried out in the paediatric population to further understand the prognostic and diagnostic roles of NT-proBNP.

The evaluation of the burden of multisystem inflammatory syndrome in children on health economics

Objectives

This study aimed to evaluate the diagnostic tests and treatments applied in patients with multisystem inflammatory syndrome in children (MIS-C) and to determine the effect of the disease on health costs.

Patients and methods

This retrospective cohort study included 59 MIS-C patients (40 males, 19 females; mean age: 7.7±4.2 years; range, 4 months to 16.5 years) who were admitted and treated between April 1, 2020, and November 1, 2021. Demographic and clinical features with hospital costs and length of stay were retrospectively reviewed from the medical files and computerized system of the hospital. Direct medical care costs of items were calculated with the hospital perspective using a combination of microcosting technique (resource-based accounting method) and hospital list data. Cases were classified as mild, moderate, or severe, and the patients were divided into two groups: the mild group and the moderate-severe group. Classification was determined by the vasoactive inotropic score (VIS), degree of respiratory support, and evidence of organ damage.

Results

The mean age of the cases in the mild group was 6.5±3.7 years, and the mean age of the cases in the moderate-severe group was 9.2±4.3 years. Of 59 patients, 19 (32.2%) were followed up in the pediatric intensive care unit. The median duration of hospitalization in the hospital was 8 (interquartile range: 7-12) days. The total cost of the patients hospitalized with the diagnosis of MIS-C during the study period was 849,242.93$, and the mean cost per patient was 14,393.94±9,631.92$. In the distribution of the total cost of hospitalization according to expenses, the highest rate was pharmacy and blood products (51.99%) and IVIG costs (43.99%). While the mean total cost per person was 13,682.87±8,799.63$ in mild cases, it was 16,433.82±9,440.02$ in moderate-severe cases, and no statistically significant relationship was found between the two groups (p>0.05). There was no difference in the mean cost per patient between the cases with and without heart, lung, kidney, or neurologic involvement and advanced respiratory support (p>0.05). There was a strong positive correlation between the total costs and age (r=0.883, n=59, p<0.0001), with increased amount of costs with increased age.

Conclusion

In the study, no statistically significant correlation was found between the total cost of per person in the mild group and the moderate-severe group (p>0.05). This finding may be due to the wide use of IVIG in MIS-C treatment, in addition to low transfer rates to pediatric intensive care units due to high-flow nasal cannula usage.

The metaproteome of the gut microbiota in pediatric patients affected by COVID-19

Introduction

The gut microbiota (GM) play a significant role in the infectivity and severity of COVID-19 infection. However, the available literature primarily focuses on adult patients and it is known that the microbiota undergoes changes throughout the lifespan, with significant alterations occurring during infancy and subsequently stabilizing during adulthood. Moreover, children have exhibited milder symptoms of COVID-19 disease, which has been associated with the abundance of certain protective bacteria. Here, we examine the metaproteome of pediatric patients to uncover the biological mechanisms that underlie this protective effect of the GM.

Methods

We performed nanoliquid chromatography coupled with tandem mass spectrometry on a high resolution analytical platform, resulting in label free quantification of bacterial protein groups (PGs), along with functional annotations via COG and KEGG databases by MetaLab-MAG. Additionally, taxonomic assignment was possible through the use of the lowest common ancestor algorithm provided by Unipept software.

Results

A COVID-19 GM functional dissimilarity respect to healthy subjects was identified by univariate analysis. The alteration in COVID-19 GM function is primarily based on bacterial pathways that predominantly involve metabolic processes, such as those related to tryptophan, butanoate, fatty acid, and bile acid biosynthesis, as well as antibiotic resistance and virulence.

Discussion

These findings highlight the mechanisms by which the pediatric GM could contribute to protection against the more severe manifestations of the disease in children. Uncovering these mechanisms can, therefore, have important implications in the discovery of novel adjuvant therapies for severe COVID-19.

Cardiac manifestations of multisystem inflammatory syndrome of children after SARS-CoV-2 infection: a systematic review and meta-analysis

This systematic review and meta-analysis were conducted to evaluate the prevalence of cardiac manifestations associated with multisystem inflammatory syndrome in children worldwide. We conducted electronic searches in Ovid MEDLINE, Ovid EMBASE, and the World Health Organization COVID-19 Literature Database from the inception of the SARS-CoV-2 pandemic to 1 January, 2022. Three authors independently screened the abstracts to determine eligibility, assessed methodology in the full texts, and extracted the data.We identified 2848 citations; 94 studies (14,932 patients) were included. The prevalence of vasopressors was 48.2% (95% CI 45.1%, 51.3%), left ventricular systolic dysfunction occurred in 37.2% (95% CI 34.1%, 40.3%), myocarditis in 34.1% (95% CI 30.5%, 37.8%), electrocardiographic dysrhythmias and abnormalities detected in 23.1% (95% CI 18.8%, 27.6%), coronary abnormalities identified in 18% (95% CI 16%, 20%), extracorporeal membrane oxygenation deployed in 2.2% (95% CI 1.7%, 2.8%), and mortality rate of 2.2% (95% CI 1.7%, 2.7%). A sensitivity analysis was performed after removing eleven studies with high bias, and the adjusted prevalence was not different than the original evaluation.In this meta-analysis of the largest cohort of multisystem inflammatory syndrome in children patients to date, we established the most accurate prevalence of the most common cardiac manifestations. Providers will subsequently have more precise data to anticipate patient outcomes and approach discussions concerning the frequency of monitoring outside the acute hospital period.

Alterations in B and NK cells highly correlate with disease severity in children with COVID-19

Background/aim

Children with coronavirus disease 2019 (COVID-19) present milder symptoms than adults and are at lower risk of hospitalization and life-threatening complications. However, the kinetics of lymphocyte subsets and serum immunoglobulins in the peripheral blood during COVID-19 infection remains unclear. In this study, it was aimed to determine the changes in hematological and immunological parameters, especially in the lymphocyte subsets, in the peripheral blood of children with different COVID-19 disease severity.

Materials and methods

The study was planned as a prospective cohort and included 68 children aged 0-18 years who were admitted to Ege University Faculty of Medicine Department of Pediatrics and diagnosed with COVID-19 infection between May 2020 and December 2021. In addition to demographic characteristics, clinical findings, and severity criteria, hematological, biochemical, and immunological laboratory (T/B lymphocyte subgroups, serum immunoglobulins) results were noted and examined if there were some correlations between disease severity and the laboratory values.

Results

In the study group, while 60.6% (n = 40) of the patients received treatment in the hospital, 10.6% (n = 7) needed intensive care treatment. Lymphopenia (35.3%) was more common than neutropenia (14.7%) in the COVID-19-infected children. CD19+ B cells were low in a very high percentage of patients (26.5%), and 16.2% had low levels of NK cells. Significant correlation between disease severity and CD19+lymphocytes, CD19+CD38+IgMlow lymphocytes, CD19+CD38+CD27highIgMhigh lymphocytes, CD19+CD81+ lymphocytes (p = 0.001, p = 0.008, p = 0.014, p = 0.025, and rs = 0.394, rs = 0.326, rs = 0.303, rs = 0.280, respectively), significant inverse correlation between disease severity and absolute lymphocytes counts and CD3-CD16+CD56+ lymphocytes (p = 0.004, 0.014, and rs = -0.353, rs = -0.304, respectively) were observed. The percentage of hospitalized patients with low CD3 levels (15%) was significantly higher than that of the outpatients with low CD3 levels.

Conclusion

As the severity of the disease increased, the CD19+, CD19+CD38+IgMlow, CD19+CD38+CD27highIgMhigh, and CD19+CD81+ lymphocytes percentages increased, while the lymphocyte count and NK cell percentage decreased. Therefore, detecting these prognostic immunobiomarkers related to the severity of the disease may contribute considerably to management of the illness.

Association among COVID-19, multisystem inflammatory syndrome in children, and oral health status

The pathophysiology of multisystem inflammatory syndrome in children (MIS-C) and associated oral symptoms have not been clarified yet. The aim of the present study was to compare the oral health status of children with MIS-C-associated Coronavirus disease 2019 (COVID-19) and COVID-19. A total of 54 children with SARS-CoV-2 infection, 23 with MIS-C-associated COVID-19 and 31 with asymptomatic, mild, and moderate COVID-19 were recruited for the present cross-sectional study. Sociodemographic variables, medical examinations, oral hygiene habits, and extraoral and intraoral findings (DMFT/dmft index, OHI scores, and oral mucosal changes) were recorded. The t-test for independent samples and the Mann-Whitney U test were used (p < 0.05). MIS-C was found to be associated with chapped lips (all patients) and oral mucosal changes, including erythema, white lesion, strawberry tongue, and swelling of the gingiva as compared to the COVID-19 group (frequency of more than one mucosal change: 100% vs. 35%) (p < 0.001). Children with MIS-C presented higher DMFT/dmft scores (DMFT/dmft 5.52 ± 3.16 for the MIS-C group vs. 2.26 ± 1.80 for the COVID-19 group) (p < 0.01). Elevated OHI scores were also associated with MIS-C (mean ± SD: 3.06 ± 1.02 (MIS-C) vs. 2.41 ± 0.97 (COVID-19) (p < 0.05). Oral manifestations, mainly strawberry and erythematous tongue, were characteristic features of MIS-C. Prevalence of oral/dental symptoms was elevated in children with MIS-C when compared to COVID-19. Therefore, dental professionals should be aware of the oral manifestations associated with MIS-C, which may have high mortality and morbidity rates.

Changing Disease Course of Crimean-Congo Hemorrhagic Fever in Children, Turkey

Crimean-Congo hemorrhagic fever (CCHF), endemic in certain regions of the world, is listed as a priority disease with pandemic potential. Since CCHF was first identified in Turkey, children have been known to experience milder disease than adults. However, during the COVID-19 pandemic, we observed an unusually severe disease course, including hemophagocytic lymphohistiocytosis (HLH). We examined cytokine/chemokine profiles of 9/12 case-patients compared with healthy controls at 3 time intervals. Interferon pathway-related cytokines/chemokines, including interleukin (IL) 18, macrophage inflammatory protein 3α, and IL-33, were elevated, but tumor necrosis factor-α, IL-6, CXCL8 (formerly IL-8), and cytokines acting through C-C chemokine receptor 2 and CCR5 were lower among case-patients than controls. Interferon pathway activation and cytokines/chemokines acting through CCR2 and CCR5 improved health results among children with severe CCHF. Children can experience severe CCHF, including HLH, and HLH secondary to CCHF can be successfully treated with intravenous immunoglobulin and steroid therapy.

The comparison of COVID-19 vs seasonal influenza in children

BACKGROUND

Influenza in children has been well described, whereas there has been a paucity of pediatric data regarding COVID-19. It is crucial for clinicians to differentiate cases of COVID-19 from cases of influenza because of the upcoming influenza season in the new pandemic era.

METHODS

This retrospective study included pediatric patients who were diagnosed with laboratory-confirmed COVID-19 between March and September 2020, or seasonal influenza between October 2019 and March 2020.

RESULTS

A total of 315 children were included in this study; 151 were diagnosed with influenza and 164 had confirmed COVID-19. The median age of patients with COVID-19 was 10 years (interquartile range [IQR]: 3-15 years), whereas the median age of patients with influenza was 4 years (IQR: 1-6 years) (p = 0.001). In the COVID-19 group, 6.3% of patients had underlying diseases, the most frequent being neurological conditions (3%). In the influenza group, 20.9% of patients had an underlying disease, the most frequent being asthma (14.5%). Fever (odds ratio [OR]: 20.476; 95% confidence interval [CI]: 2.438-171.995; p = 0.005), dyspnea/tachypnea (OR 13.950; 95% CI: 2.607-74.634; p = 0.002), and increased C-reactive protein (CRP) (OR: 7.650; 95% CI: 2.094-27.955; p = 0.002) were main predictors of influenza diagnosis in comparison to COVID-19. Lymphopenia was detected in 43.2% of patients with influenza and 19.9% of patients with COVID-19 (p = 0.001).

CONCLUSIONS

The accurate differentiation between "influenza or COVID-19" seems possible by evaluating a combination of factors including cough, fever, vomiting, leucopenia, lymphopenia, pneumonia, in pediatric patients with high CRP as well as age.

A cursed goodbye kiss from severe acute respiratory syndrome-coronavirus-2 to its pediatric hosts: multisystem inflammatory syndrome in children

PURPOSE OF REVIEW

We aimed to summarize a novel disease called multisystem inflammatory syndrome in children (MIS-C), which develops several weeks after a severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) illness.

RECENT FINDINGS

Given the rarity of the disease, the question of why a minority of children develop MIS-C is not known. Certain intrinsic susceptibility factors in the host have been described. In addition to hyperinflammation induced by the innate and acquired immune cells, evidence of molecular mimicry was presented for the disease pathogenesis. As there is an increasing number of infected individuals and mass vaccination schedules, concerns regarding the usefulness of the existing diagnostic criteria sets raised.

SUMMARY

Although children are likely to have a milder COVID-19 course compared with adults, MIS-C as a postinfectious and life-threatening complication was reported in the pediatric age. After 2 years of the disease definition, optimal treatment regimes, effective preventive measures, and long-term outcomes are still debated.

Multisystem inflammatory syndrome in children: clinical presentation, management, and short- and long-term outcomes

OBJECTIVE

In this study, it was aimed to evaluate the demographic, clinical and laboratory characteristics of MIS-C patients in our hospital, to share our treatment approach, and to assess the outcomes of short- and long-term follow-up.

METHODS

MIS-C patients who were admitted and treated in our hospital between July 2020 and July 2021 were evaluated. Demographic, clinical, laboratory, and follow-up data were collected from patient records retrospectively.

RESULTS

A total of 123 patients with MIS-C (median age, 9.6 years) were included the study. Nineteen (15.4%) were mild, 56 (45.6%) were moderate, and 48 (39%) were severe MIS-C. High CRP, ferritin, pro-BNP, troponin, IL-6, and D-dimer values were found in proportion to the severity of the disease (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.005, p < 0.001), respectively. Two (1.6%) patients died. The mean follow-up period was 7.8 months. Valve failure, left ventricular dysfunction/hypertrophy, coronary involvement, and pericardial effusion were the most common cardiac pathologies in the short- and long-term follow-up of the patients. In the long-term follow-up, the most common reasons for admission to the hospital were recurrent abdominal pain (14.2%), cardiac findings (14.2%), pulmonary symptoms (8%), fever (7.1%), neuropsychiatric findings (6.2%) and hypertension (3.5%). Neuropsychiatric abnormalities were observed significantly more common in severe MIS-C patients at follow-up (p = 0.016). In the follow-up, 6.2% of the patients required recurrent hospitalization.

CONCLUSION

MIS-C is a serious and life-threatening disease, according to short-term outcomes. In addition to the cardiac findings of patients with MIS-C, long-term outcomes such as neuropsychiatric findings, persistent gastrointestinal symptoms, fever and pulmonary symptoms should be monitored. Key Points • In MIS-C patients, attention should be paid not only to cardiac findings, but also to symptoms related to other systems. • Patients should be followed up in terms of neuropsychiatric findings, persistent gastrointestinal symptoms, fever and pulmonary symptoms that may occur during follow-up.

Epidemiology and clinical evolution of non-multisystem inflammatory syndrome (MIS-C) dermatological lesions in pediatric patients affected by SARS-CoV-2 infection: A systematic review of the literature

COVID-19 can present with a range of skin manifestations, some of which specific of the pediatric age. The aim of this systematic literature review was to determine the type, prevalence, time of onset, and evolution of cutaneous manifestations associated with COVID-19 in newborns, children, and adolescents, after excluding multisystem inflammatory syndrome in children (MIS-C). PubMed, Tripdatabase, ClinicalTrials, and Cochrane Library databases were searched using an ad hoc string for case reports/series and observational studies, published between December 2019 and February 2022. Study quality was assessed using the STROBE and CARE tools. Seventy-three (49 case reports/series and 24 studies) out of 26,545 identified articles were included in the analysis. Dermatological lesions were highly heterogeneous for clinical presentation, time of onset, and association with other COVID-19 manifestations. Overall, they mainly affected the acral portions, and typically presented a favorable outcome. Pseudo-chilblains were the most common.

CONCLUSIONS

Mucocutaneous manifestations could be the only/predominant and early manifestation of COVID-19 that could precede other more severe manifestations by days or weeks. Therefore, physicians of all disciplines should be familiar with them.

WHAT IS KNOWN

• A variety of cutaneous manifestations have been reported in association with COVID-19. • Urticaria, maculopapular, or vesicular rashes can occur at any age, while chilblains and erythema multiforme are more common in children and young patients.

WHAT IS NEW

• Skin lesions related to SARS-CoV-2 infection often show a peculiar acral distribution. • Mucocutaneous lesions of various type may be the only/predominant manifestation of COVID-19; they could present in paucisymptomatic and severely ill patients and occur at different stages of the disease.

MIS-C related to SARS-CoV-2 infection: a narrative review of presentation, differential diagnosis, and management

Multisystem Inflammatory Syndrome in Children (MIS-C), a rare condition, has been reported approximately 2-4 weeks after the onset of COVID-19 in children and adolescents, causing inflammation in multiple systems, including cardiovascular and respiratory, digestive, and central nervous systems. This condition is also known as hyperinflammatory shock, Kawasaki-like disease, and Pediatric Inflammatory Multisystem Syndrome (PIMS). The signs and symptoms include but are not limited to fever, rash, peripheral edema, gastrointestinal symptoms, conjunctivitis, and shock. Thirty-eight studies met our criteria, with a total of 5822 patients. The most affected population was between 5-18 years of age. We noted that MIS-C presented with a wide range of signs and symptoms that overlap with Kawasaki Disease, including high fever, sore throat, malaise, tachypnea, tachycardia, conjunctival injection, mucosal edema, cardiac involvement, and gastrointestinal symptoms. It causes an increase in IL-17A, IL-6, and arterial damage, a distinct difference from Kawasaki disease. The laboratory findings in MIS-C showed an increase in inflammatory markers like CRP, ESR, ferritin, leukocytes, and TNF-α. WHO stated that 23% of affected children with MIS-C had underlying conditions like chronic lung diseases, cardiovascular disease, and immunosuppression. In most affected children, aspirin and IVIG were successful, which resulted in a decrease in the inflammatory markers. We find that MIS-C is a rare, but potentially fatal pediatric complication, after COVID-19 infection. The aim of this article is to study the emerging relationship between COVID-19 and MIS-C in children and adolescents affected by this condition, to discuss the immunological mechanisms, and explore potential therapies.

A retrospective comparative analysis of factors affecting the decision and outcome of initial intravenous immunoglobulin alone or intravenous immunoglobulin plus methylprednisolone use in children with the multisystem inflammatory syndrome

BACKGROUND

For children with the multisystem inflammatory syndrome(MIS-C), intravenous immunoglobulins (IVIG) with or without methylprednisolone are the most effective treatment. In this study, IVIG combined with methylprednisolone was compared to IVIG used alone in children with MIS-C.

METHODS

This retrospective cohort study was carried out between April 1, 2020, and November 1, 2021. This study covered all children with MIS-C. According to whether they received IVIG alone or IVIG with methylprednisolone as an initial treatment for MIS-C, the patients were split into two groups. The IVIG dosage for the patients in group I was 2 gr/kg, whereas the IVIG dosage for the patients in group II was 2 gr/kg + 2 mg/kg/day of methylprednisolone. These two groups were contrasted in terms of the frequency of fever, length of hospital stay, and admission to the pediatric intensive care unit.

RESULTS

The study comprised 91 patients who were diagnosed with MIS-C and were under the age of 18. 42 (46.2%) of these patients were in the IVIG alone group (group I), and 49 (53.8%) were in the IVIG + methylprednisolone group (group II). Patients in group II had a severe MIS-C ratio of 36.7%, which was substantially greater than the rate of severe MIS-C patients in group I (9.5%) (p 0.01). When compared to group I (9.5%), the rate of hypotension was considerably higher in group II (30.6%) (p = 0.014). Additionally, patients in group II had considerably higher mean serum levels of C-reactive protein. The incidence of fever recurrence was 26.5% in group II and 33.3% in group I, however the difference was not statistically significant (p > 0.05).

CONCLUSIONS

The choice of treatment for patients with MIS-C should be based on an individual evaluation. In MIS-C children with hypotension and/or with an indication for a pediatric intensive care unit, a combination of IVIG and methylprednisolone may be administered. For the treatment modalities of children with MIS-C, however, randomized double-blind studies are necessary.

COVID-19 disease in children presenting to the pediatric emergency department: A multicenter study with 8886 cases from Turkey

Background

The aim was to evaluate the epidemiological, clinical, laboratory, and radiologic data of children with SARS-CoV-2 positivity by polymerase chain reaction (PCR) together with treatment strategies and clinical outcomes and to evaluate cases of multisystem inflammatory syndrome in children (MIS-C) in this population.

Methods

This was a multicenter retrospective observational cohort study performed in the pediatric emergency departments of 19 tertiary hospitals. From March 11, 2020, to May 31, 2021, children who were diagnosed with confirmed nasopharyngeal/tracheal specimen SARS-CoV-2 PCR positivity or positivity for serum-specific antibodies against SARS-CoV-2 were included. Demographics, presence of chronic illness, symptoms, history of contact with SARS-CoV-2 PCR-positive individuals, laboratory and radiologic investigations, clinical severity, hospital admissions, and prognosis were recorded.

Results

A total of 8886 cases were included. While 8799 (99.0%) cases resulted in a diagnosis of SARS-CoV-2 with PCR positivity, 87 (1.0%) patients were diagnosed with MIS-C. Among SARS-CoV-2 PCR-positive patients, 51.0% were male and 8.5% had chronic illnesses. The median age was 11.6 years (IQR: 5.0–15.4) and 737 (8.4%) patients were aged <1 year. Of the patients, 15.5% were asymptomatic. The most common symptoms were fever (48.5%) and cough (30.7%) for all age groups. There was a decrease in the rate of fever as age increased (p < 0.001); the most common age group for this symptom was <1 year with the rate of 69.6%. There was known contact with a SARS-CoV-2 PCR-positive individual in 67.3% of the cases, with household contacts in 71.3% of those cases. In terms of clinical severity, 83 (0.9%) patients were in the severe-critical group. There was hospital admission in 1269 (14.4%) cases, with 106 (1.2%) of those patients being admitted to the pediatric intensive care unit (PICU). Among patients with MIS-C, 60.9% were male and the median age was 6.4 years (IQR: 3.9–10.4). Twelve (13.7%) patients presented with shock. There was hospital admission in 89.7% of these cases, with 29.9% of the patients with MIS-C being admitted to the PICU.

Conclusion

Most SARS-CoV-2 PCR-positive patients presented with a mild clinical course. Although rare, MIS-C emerges as a serious consequence with frequent PICU admission. Further understanding of the characteristics of COVID-19 disease could provide insights and guide the development of therapeutic strategies for target groups.

Safety of COVID-19 vaccines and disease flares after vaccines in children with rheumatic disease

OBJECTIVES

Wide spread availability of safe and effective vaccines for COVID-19 in all countries is the best hope to end the COVID-19 pandemic. However, in developing countries, the hesitancy of the society about vaccination is an important problem in terms of public health. This study aimed to investigate the acceptability and tolerability of COVID-19 vaccines in the pediatric population diagnosed with rheumatic disease, as well as the attitudes towards these vaccines.

METHODS

This is an observational, cross sectional, single center study. Pediatric patients with at least one diagnosis of rheumatic disease were included in this study to investigate patient and family acceptability and safety of COVID-19 vaccines.

RESULTS

A total of 228 patients with rheumatic disease were included in this study. Ninety nine (43.4%) of the patients were juvenile idiopathic arthritis. One hundred and five (46%) of the patients were using biological agent treatment for their rheumatic disease, whereas 123 (54%) of the patients were not. No serious adverse effect related to the COVID-19 vaccine were observed in any of the patients. No disease activation was observed in any of them.

CONCLUSION

There are only a few studies evaluating of the safety and disease flare of COVID-19 vaccines in children with rheumatic disease. Although this study has some limitations, such as the small sample size of patients with different diagnoses, it appears that there is no increase in COVID-19 vaccination-related harms in the patients with rheumatic disease.

Management of acute abdomen during the active disease course of COVID-19 and multisystem inflammatory syndrome in children

Purpose

To evaluate the management of children with severe gastrointestinal symptoms during the disease course of COVID-19 and multisystem inflammatory syndrome (MIS-C).

Methods

After ethical approval, we reviewed the medical records, retrospectively, of children with COVID-19 or MIS-C requiring surgical consultation for severe gastrointestinal symptoms.

Results

The subjects comprised 15 children, 13 with MIS-C and 2 with COVID-19. Twelve children (80%) had been in known close contact with a person with SARS-CoV-19 and 13 were positive for Anti-SARS-CoV-2 IgG. All the children had experienced fever for at least 1 day and had signs of involvement of two or more systems. Three patients required surgical intervention: one underwent surgical exploration with a presumptive diagnosis of acute appendicitis in the referring center and was transported to our center following clinical deterioration, where a diagnosis of MIS-C was confirmed; and the remaining two developed appendicitis during hospitalization for COVID-19. All three patients had a longer duration of abdominal pain, a higher number of lymphocytes, and a lower level of inflammatory markers than the non-surgically managed patients. None of the patients presenting with MIS-C underwent surgical exploration.

Conclusion

Gastrointestinal involvement may mimic acute abdomen in children with COVID-19. Thus, children presenting with acute abdomen in the pandemic era require careful evaluation and prompt diagnosis to avoid unnecessary surgical intervention.

Differences and similarities of multisystem inflammatory syndrome in children, Kawasaki disease and macrophage activating syndrome due to systemic juvenile idiopathic arthritis: a comparative study

To compare the clinical and laboratory findings of multisystem inflammatory syndrome in children (MIS-C), patients with Kawasaki disease (KD) and with macrophage activating syndrome due to systemic juvenile idiopathic arthritis (sJIA-MAS) on real-life data. Patients diagnosed with MIS-C, KD, and sJIA-MAS from 12 different centers in Turkey who were followed for at least 6 months were included in the study. Demographic, clinical, and laboratory findings of all patients were analyzed. A total of 154 MIS-C, 59 KD, and 31 sJIA-MAS patients were included. The median age of patients with MIS-C were higher than those with KD while lower than those with sJIA-MAS (8.2, 3, 12 years, respectively). Myalgia (39.6%), cardiac (50.6%), gastrointestinal (72.7%), and neurological (22.1%) involvements were more common in patients with MIS-C compared to others. MIS-C patients had lower levels of lymphocyte (950 vs 1700 cells/µl) and thrombocyte (173,000 vs 355,000 cells/µl) counts and higher pro-BNP (1108 vs 55 pg/ml) levels than KD. Ferritin levels were higher in patients with MIS-C compared to patients with KD while they were lower than patients with sJIA-MAS (440, 170, 10,442 ng/ml, respectively). Patients with MIS-C had a shorter duration of hospitalization than sJIA-MAS (p = 0.02) while they required intensive care unit admission more frequently (55 vs 8 patients, p < 0.001). The median MAS/sJIA score of MIS-C patients was - 1.64 (- 5.23 to 9.68) and the median MAS/sJIA score of sJIA-MAS patients was -2.81 ([- 3.79] to [- 1.27]). MIS-C patients displayed certain differences in clinical and laboratory features when compared to KD and sJIA-MAS. Definition of the differences and similarities between MIS-C and the other intense inflammatory syndromes of childhood such as KD and MAS will help the clinicians while making timely diagnosis.

Histopathological and Clinical Analysis of Skin Rashes in Children With Multisystem Inflammatory Syndrome Associated With COVID-19

INTRODUCTION

A new entity, which occurs a few weeks after SARS-CoV-2 infection and resembling incomplete Kawasaki disease or toxic shock syndrome, has been defined and named multisystem inflammatory syndrome (MIS-C) associated with COVID-19 in children. The aim of our study was to describe histopathological characteristics of skin lesions of MIS-C patients to reveal whether there is a relationship between histopathological features and clinical manifestations.

MATERIALS AND METHODS

Seventeen who had skin involvement of 57 patients who were diagnosed with MIS-C between December 2020 and February 2021 were included in this prospective study. Demographic information, laboratory findings, and patients' managements were recorded. Skin biopsies were taken simultaneously of each patient. Formalin-fixed, paraffin-embedded skin samples were examined microscopically.

RESULTS

The rate of skin rash was 30% in patients with MIS-C and was predominantly the maculopapular type. The anatomical distribution of the rash was evaluated as localized in 10 and generalized in 7 patients. In patients with myocarditis, C-reactive protein and fibrinogen were found to be significantly higher, and lymphocyte and albumin values were found to be low. Herpes-like inclusions were found in the microscopic examination of 2 patients with a history of zona zoster in themselves or in their mother. There was a significant difference between keratinocyte necrosis and some clinical parameters.

DISCUSSION

Localized skin lesions appear to be associated with a more severe inflammatory.

Immune profile of children diagnosed with multisystem inflammatory syndrome associated with SARS-CoV-2 infection (MIS-C)

Introduction

The pathophysiology of multisystem inflammatory syndrome associated with SARS-CoV-2 infection (MIS-C) remains poorly understood. This study aimed to define peripheral blood immune features in patients with MIS-C.

Material and methods

We analyzed seven children diagnosed with MIS-C between April 1 and May 15, 2021, in St. Joseph's Children's Hospital in Poznan (Poland).

Results

All patients had elevated inflammatory markers, IgG antibodies against SARS-CoV-2, and lymphopenia with a marked decrease in CD4+ and CD8+ T cells. The majority of CD4+ T cells were naive cells. Almost all (6/7) of the analyzed patients had a higher CD4+/CD8+ T cell ratio than average values. B cells were within the normal range - the majority were non-memory cells.

Conclusions

Children with MIS-C do not resemble adults during COVID-19 recovery. The immune profile of the studied patients differs from that of children with Kawasaki disease (KD), but it is similar to that of adults with severe COVID-19. The proposed explanation is a profound lymphopenia caused by SARS-CoV-2 infection - which persists for weeks - as a result leading to uncontrolled inflammation. In COVID-19 patients the T cell level returns to normal after the second week of the disease. Our data suggest that in children prolonged lymphopenia after COVID-19 can be a practical marker for possible MIS-C alert. If there is a continuum from lymphopenia to MIS-C, there is room for screening and prevention. Further studies are needed to determine whether steroid treatment introduced in a child with prolonged lymphopenia could stop the inflammatory process.

The difference of the inflammatory milieu in MIS-C and severe COVID-19

BACKGROUND

Coronavirus disease 19 (COVID-19) may have a severe course in children. Multisystem inflammatory syndrome in children (MIS-C) is the post-COVID complication characterized by an exaggerated inflammation, observed in children. However, data on the underlying pathophysiology are sparse. We therefore aimed to assess the cytokine and chemokine profiles of children with MIS-C and compare these to life-threatening severe SARS-CoV-2 and healthy controls (HCs) to shed light on disease pathophysiology.

METHODS

Samples of 31 children with MIS-C, 10 with severe/critical COVID-19 and 11 HCs were included. Cytokine and chemokine profiles were studied and compared in between groups.

RESULTS

Most cytokines and chemokines related to IL-1 family and IFN-γ pathway (including IL-18 and MIG/CXCL9) and IL-17A were significantly higher in the MIS-C group when compared to the severe/critical COVID-19 group and HCs. IP-10/CXCL10 and IL-10 were higher in both MIS-C patients and severe/critical COVID-19 compared to HCs.

CONCLUSION

Our results suggest that IL-1 and IFN-γ pathways play an important role in the pathophysiology of MIS-C.

IMPACT

This study defines a pattern of distinctive immune responses in children with MIS-C and in patients with severe/critical COVID-19. As the COVID-19 pandemic continues, biomarkers to identify MIS-C risk are needed to guide our management that study results may shed light on it.

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

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

Clinical features and outcomes of 76 patients with COVID-19-related multi-system inflammatory syndrome in children

OBJECTIVES

Multi-system inflammatory syndrome in children (MIS-C) is a less understood and a rare complication of coronavirus disease-2019 (COVID-19). Given the scarce data regarding this novel disease, we aimed to describe the clinical features and outcomes of our patients with MIS-C and to evaluate the associated factors for the pediatric intensive care unit (PICU) admission.

METHODS

The MIS-C patients under 18 years old diagnosed and treated in three referral centers between July 2020 and March 2021 were included. Data of the patients were retrospectively obtained from their medical records.

RESULTS

Overall, 76 subjects (24 females) with a mean age of 8.17 ± 4.42 years were enrolled. Twenty-seven (35.5%) patients were admitted to the PICUs. The two most common systemic involvement patterns were cardiac and gastrointestinal. There was only one lethal outcome in a patient with underlying acute lymphoblastic leukemia. Those with higher procalcitonin levels at admission were found to stay longer in the hospital (r = 0.254, p = 0.027). The risk of PICU admission increased with age (aOR: 1.277; 95% CI: 1.089-1.498; p = 0.003) and with decreased initial serum albumin levels (aOR: 0.105; 95% CI: 0.029-0.378; p = 0.001).

CONCLUSION

Although there is a wide clinical variability among the patients with MIS-C, we suggest that those with older age and lower initial serum albumin levels merit close monitoring due to their higher risk for PICU admission. Key Points • Although there is a wide variability regarding the management process among clinicians, MIS-C is a rare, severe, less understood complication of COVID-19 that may cause rapid clinical deterioration in the patients. • Clinicians should be aware of this condition in children with persistent fever and a family history of COVID-19. • Older age and low serum albumin levels are the independent predictors for the pediatric intensive care unit admission among MIS-C patients.

Current Understanding of Multisystem Inflammatory Syndrome (MIS-C) Following COVID-19 and Its Distinction from Kawasaki Disease

PURPOSE OF REVIEW

In this article, I have reviewed current reports that explore differences and similarities between multisystem inflammatory syndrome in children (MIS-C) and other known multisystem inflammatory diseases seen in children, particularly Kawasaki disease.

RECENT FINDINGS

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human coronavirus causing the COVID-19 disease which emerged in China in December 2019 and spread rapidly to the entire country and quickly to other countries. Currently, there is a pandemic of SARS-CoV-2 infection that results in 20% of patients admitted to hospital with illness, with 3% developing intractable acute respiratory distress syndrome (ARDS) with high mortality. However, pediatric COVID-19 is still reported to be a mild disease, affecting only 8% of children. Pathogenesis in children is comparable to adults. There are suggested impaired activation of IFN-alpha and IFN regulator 3, decreased cell response causing impaired viral defense, yet the clinical course is mild, and almost all children recover from the infection without major complications. Interestingly, there is a subset of patients that develop a late but marked immunogenic response to COVID-19 and develop MIS-C. Clinical features of MIS-C resemble certain pediatric rheumatologic diseases, such as Kawasaki disease (mucocutaneous lymph node syndrome) which affects small-medium vessels. Other features of MIS-C resemble those of macrophage activation syndrome (MAS). However, recent research suggests distinct clinical and laboratory differences between MIS-C, Kawasaki disease, and MAS. Since the start of the SARS-CoV-2 pandemic, MIS-C has become the candidate for the most common cause of acquired heart disease in children.

SARS-CoV-2-related MIS-C: A key to the viral and genetic causes of Kawasaki disease?

Multisystem inflammatory syndrome in children (MIS-C) emerged in April 2020 in communities with high COVID-19 rates. This new condition is heterogenous but resembles Kawasaki disease (KD), a well-known but poorly understood and clinically heterogenous pediatric inflammatory condition for which weak associations have been found with a myriad of viral illnesses. Epidemiological data clearly indicate that SARS-CoV-2 is the trigger for MIS-C, which typically occurs about 1 mo after infection. These findings support the hypothesis of viral triggers for the various forms of classic KD. We further suggest that rare inborn errors of immunity (IEIs) altering the immune response to SARS-CoV-2 may underlie the pathogenesis of MIS-C in some children. The discovery of monogenic IEIs underlying MIS-C would shed light on its pathogenesis, paving the way for a new genetic approach to classic KD, revisited as a heterogeneous collection of IEIs to viruses.