ABSTRACT
Introduction In November 2019, the first case of SARS-CoV-2 infection was reported in China, the first European case was declared 2 months later in January 2020. While the pediatric population seemed to be less affected by SARS-CoV-2, an alert was launched in April 2020 following multiple cases of multisystem inflammatory syndrome in children (MIS-C), secondary to SARS-CoV-2 infection. The presentation shares clinical features with Kawasaki disease but involves almost systematically cardiac dysfunction. Cardiac involvement is central in MIS-C and represents the main cause of morbidity. Objective In this study, we therefore aimed to assess the myocardial damage in patients with MIS-C using MRI during the acute phase as well as left ventricular and atrial longitudinal strain during the acute phase and after recovery. Method We performed a single-center prospective cohort and case-control study. Between September 2020 and January 2022, we included 39 patients hospitalized for MIS-C in our center. We performed left ventricular and atrial longitudinal 2D strain analysis on admission and during follow-up;the analysis was compared to a matched control population. Patients above 4 years old with increased troponin underwent cardiac MRI. Results Of 22 patients who underwent cardiac MRI, 14 (64%) presented myocardial edema and 6 (27%) late gadolinium enhancement, the latter being associated with myopericarditis and impaired LVEF (P<0.001), older patients (P=0.027) and elevated ferritin (P=0.03). We found a decrease in left ventricular and atrial longitudinal strain on admission as compared to controls with a significant improvement at 1 month post-discharge (P<0.0001). The alteration in LV strain persisted beyond one month according the comparison with the control population (P=0.01). Conclusion Only little is known about the long-term follow-up and prognosis in MIS-C patients. Our study demonstrated the myocardial inflammation during the acute phase of MIS-C as well as the impaired LA and LV myocardial deformation that persists for at least several weeks after the acute phase. Thus, we believe MRI and LV/LA strain could help us individualize our MIS-C patients follow-up.
ABSTRACT
Introduction: At the end of April 2020, European clinicians warned the Public Health Agencies about an abnormal increase of Kawasakilike diseases and myocarditis requiring critical care support in the context of the ongoing COVID-19 epidemic in children. American clinicians also reported a large outbreak of severe inflammation in children following COVID-19 infection, a condition that is now named Pediatric Inflammatory Multisystemic Syndrome (PIMS) or Multisystem Inflammatory Syndrome in children (MIS-C). Objectives: As MIS-C combines clinical features of Kawasaki disease (KD) and Toxic Shock Syndrome (TSS), we aimed to compare the immunological profile of pediatric patients with these different conditions. Methods: We analysed blood cytokine expression, and the T cell repertoire and phenotype in 36 MIS-C cases, which were compared to 16 KD, 58 TSS, and 42 COVID-19 cases. Results: We observed an increase of serum inflammatory cytokines (IL-6, IL-10, IL-18, TNF-a, IFNg, CD25s, MCP1, IL-1RA) in MIS-C, TSS and KD, contrasting with low expression of HLA-DR in monocytes. We detected a specific expansion of activated T cells expressing the Vβ21.3 T cell receptor β chain variable region in both CD4 and CD8 subsets in 75% of MIS-C patients and not in any patient with TSS, KD, or acute COVID-19;this correlated with the cytokine storm detected. The T cell repertoire returned to baseline within weeks after MIS-C resolution. Vβ21.3+ T cells from MIS-C patients expressed high levels of HLA-DR, CD38 and CX3CR1 but had weak responses to SARS-CoV- 2 peptides in vitro. Consistently, the T cell expansion was not associated with specific classical HLA alleles. Conclusion: Thus, our data suggested that MIS-C is characterized by a polyclonal Vβ21.3 T cell expansion not directed against SARS-CoV-2 antigenic peptides, which is not seen in KD, TSS and acute COVID-19.
ABSTRACT
INTRODUCTION: At the end of April 2020, three European pediatric societies published an alert on a new hyperinflammatory disorder linked to SARS-CoV-2. This disease has alternatively been called Kawasaki-like disease, pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 infection (PIMS-TS), and multisystem inflammatory syndrome in children (MIS-C). These alerts provide a clear starting point from which to study the early response of the medical and scientific community to a new disease in terms of scientific publications, and to compare the timeline of this response with levels of general public interest. To this aim, we conducted a bibliometric analysis of articles on this disease published between 1 April and 5 July 2020. METHOD: A literature search was performed using PubMed and in three preprint repositories. For each article, the name used for the disease in the title, the number of authors, the number of patients, the citations according to Google Scholar, the journal impact factor, and the Altmetric score were retrieved. Google search trends for the terms "Kawasaki" and "COVID," "COVID-19," and "coronavirus" were also retrieved, as was the number of Reuters news articles published on the topic. These data were compared longitudinally on a weekly basis. The quality of the reporting of the study was evaluated using the STROBE guidelines for observational studies with more than three patients and using the CARE guidelines for case reports of three or fewer patients. RESULTS: Eighty-six articles were included, among which ten were preprints (three of which were subsequently published) and 49 were clinical articles (57%). A total of 857 patients were described. The median number of authors per article was five (range, 1-45), the median number of patients was four (1-186), the median number of citations was one (0-170), the median Altmetric score was 12 (0-7242), and the median journal impact factor was 3.7 (1-74.7). For the clinical articles, the median percentage of STROBE or CARE checklist items satisfied was 70% (IQR, 56.75-79.25; range, 40-90). Guideline adherence was significantly higher for observational studies than for case reports (median percentage of checklist items satisfied, 78.5% vs 61.5%; P<0.001); however, guideline adherence did not differ significantly between peer-reviewed and preprint articles (median percentage of checklist items satisfied, 57% vs 72%; P=0.205). The only statistically significant difference between clinical articles and other types of articles was the number of authors (median, 7 vs 2; P=2.53E-9). Fifty-seven of the 86 articles were authored by researchers from just three countries (the USA, 31; France, 14; and the UK, 12). The names most frequently used in the title were Kawasaki-like disease (n=37), followed by MIS-C (n=27), PIM-TS (n=14), and other names involving the term "inflammatory" (n=12). Google searches for related terms peaked between weeks 18 and 21, following the initial alerts and decreased rapidly thereafter. The number of Reuters articles on the subject was correlated with Google search trends (ρ: 0.86, 95% CI [0.59; 0.96]; P=0.00016), but the number of medical articles published was not (ρ: -0.54, 95% CI [-0.87; 0.14]; P=0.11). The first small case series was published less than 2 weeks after the initial alert; however, if all articles had been deposited as preprints when they were submitted to journals, the cumulative number of reported cases would have been 300% higher in week 18 (3 vs 1), 400% higher in week 19 (44 vs 11), 70% higher in week 20 (124 vs 73), and 54% higher in week 21 (129 vs 84). CONCLUSION: In a period of 9 weeks after the initial alerts from European pediatric societies, 85 medical articles were published, involving 856 patients (one case report was published before the alerts), allowing rapid dissemination of research information. However, general public interest followed the news cycle rather than scientific releases. The quality of the reporting, as assessed by adherence to STROBE or CARE guidelines, was adequate with more than two-thirds of checklist items satisfied. Learned societies play an important role in the early dissemination of up-to-date peer-reviewed information. Preprint deposition should be encouraged to accelerate the dissemination of research information.