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Pediatrics

American Academy of Pediatrics (AAP)

All preprints, ranked by how well they match Pediatrics's content profile, based on 11 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit. Older preprints may already have been published elsewhere.

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Undiagnosed COVID-19 in households with a child with mitochondrial disease

Gordon-Lipkin, E. M.; Marcum, C.; Kruk, S.; Thompson, E.; Kelly, S. E. M.; Kalish, H.; Sadtler, K.; McGuire, P.

2022-03-23 pediatrics 10.1101/2022.03.21.22272358 medRxiv
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BackgroundThe impact of the COVID-19 pandemic on medically fragile populations, who are at higher risk of severe illness and sequelae, has not been well characterized. Viral infection is a major cause of morbidity in children with mitochondrial disease (MtD), and the COVID-19 pandemic represents an opportunity to study this vulnerable population. MethodsA convenience sampling cross-sectional serology study was conducted (October 2020 to June 2021) in households (N = 20) containing a child with MtD (N = 22). Samples (N = 83) were collected in the home using a microsampling apparatus and shipped to investigators. Antibodies against SARS-CoV-2 nucleocapsid (IgG), spike protein (IgG, IgM, IgA), and receptor binding domain (IgG, IgM, IgA) were determined by enzyme linked immunosorbent assay. ResultsWhile only 4.8% of participants were clinically diagnosed for SARS-CoV-2 infection, 75.9% of study participants were seropositive for SARS-CoV-2 antibodies. Most samples were IgM positive for spike or RBD (70%), indicating that infection was recent. This translated to all 20 families showing evidence of infection in at least one household member. For the children with MtD, 91% had antibodies against SARS-CoV-2 and had not experienced any adverse outcomes at the time of assessment. For children with recent infections (IgM+ only), serologic data suggest household members as a source. ConclusionsCOVID-19 was highly prevalent and undiagnosed in households with a child with MtD through the 2020-2021 winter wave of the pandemic. In this first major wave, children with MtD tolerated SARS-CoV-2 infection well, potentially due to household adherence to CDC recommendations for risk mitigation. FundingThis study was funded by the Intramural Research Program of the National Institutes of Health (HG200381-03). Clinical trial numberNCT04419870

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Epidemiology and role of SARS-CoV-2 Linkage in Paediatric Inflammatory Multisystem Syndrome (PIMS): A Canadian Paediatric Surveillance Program National Prospective Study

El Tal, T.; Morin, M.-P.; Morris, S.; Farrar, D. K.; Berard, R. A.; Kakkar, F.; Moore Hepburn, C.; Baerg, K.; Beaufils, C.; Bennett, T.-L.; Benseler, S. M.; Beaudoin-Bussieres, G.; Chan, K.; Cyr, C.; Dahdah, N.; Donner, E. J.; Drouin, O.; Edjoc, R.; Eljaouhari, M.; Embree, J. E.; Farrell, C.; Finzi, A.; Forgie, S.; Giroux, R.; Kang, K. T.; King, M.; Laffin Thibodeau, M.; Lang, B.; Laxer, R. M.; Luu, T. M.; McCrindle, B. W.; Orkin, J.; Papenburg, J.; Pound, C. M.; Price, V. E.; Proulx-Gauthier, J.-P.; Purewal, R.; Sadarangani, M.; Salvadori, M. I.; Thibeault, R.; Top, K. A.; Viel-Theriault, I.;

2022-05-27 pediatrics 10.1101/2022.05.27.22275613 medRxiv
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BackgroundPaediatric inflammatory multisystem syndrome (PIMS) is a rare but serious condition temporally associated with SARS-CoV-2 infection. Using the Canadian Paediatric Surveillance Program (CPSP), a national surveillance system, we aimed to 1) study the impact of SARS-CoV-2 linkage on clinical and laboratory characteristics, and outcomes in hospitalized children with PIMS across Canada 2) identify risk factors for ICU admission, and 3) establish the minimum national incidence of hospitalizations due to PIMS and compare it to acute COVID-19. MethodsWeekly online case reporting was distributed to the CPSP network of more than 2800 pediatricians, from March 2020 to May 2021. Comparisons were made between cases with respect to SARS-CoV-2 linkage. Multivariable modified Poisson regression was used to identify risk factors for ICU admission and Minimum incidence proportions were calculated. FindingsIn total, 406 PIMS cases were analyzed, of whom 202 (49{middle dot} 8%) had a positive SARS-CoV-2 linkage, 106 (26{middle dot} 1%) had a negative linkage, and 98 (24{middle dot} 1%) had an unknown linkage. The median age was 5{middle dot} 4 years (IQR 2{middle dot} 5-9{middle dot} 8), 60% were male, and 83% had no identified comorbidities. Compared to cases with a negative SARS-CoV-2 linkage, children with a positive SARS-CoV-2 linkage were older (8{middle dot} 1 years [IQR 4{middle dot} 2-11{middle dot} 9] vs. 4{middle dot} 1 years [IQR 1{middle dot} 7-7{middle dot} 7]; p<0{middle dot} 001), had more cardiac involvement (58{middle dot} 8% vs. 37{middle dot} 4%; p<0{middle dot} 001), gastrointestinal symptoms (88{middle dot} 6% vs. 63{middle dot} 2%; p<0{middle dot} 001), and shock (60{middle dot} 9% vs. 16{middle dot} 0%; p<0{middle dot} 001). At-risk groups for ICU admission include children [&ge;] 6 years and those with a positive SARS-CoV-2 linkage. No deaths were reported. The minimum incidence of PIMS hospitalizations during the study period was 5{middle dot} 6 hospitalizations per 100,000 population <18 years. InterpretationWhile PIMS is rare, almost 1 in 3 hospitalized children required ICU admission and respiratory/hemodynamic support, particularly those [&ge;] 6 years and with a positive SARS-CoV-2 linkage. FundingFinancial support for the CPSP was received from the Public Health Agency of Canada.

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Multisystem Inflammatory Syndrome in Children Managed in the Outpatient Setting: An EHR-based cohort study from the RECOVER program

Jhaveri, R.; Webb, R.; Razzaghi, H.; Schurchard, J.; Mejias, A.; Bennett, T. D.; Jone, P.-N.; Thacker, D.; Schulert, G. R.; Rogerson, C.; Cogen, J. D.; Bailey, L. C.; Forrest, C. B.; Lee, G. M.; Rao, S.

2022-08-25 pediatrics 10.1101/2022.08.25.22279225 medRxiv
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Using electronic health record data combined with primary chart review, we identified 7 children across 8 pediatric medical centers with a diagnosis of Multisystem Inflammatory Syndrome in Children (MIS-C) who were managed as outpatients. These findings should prompt a discussion about modifying the case definition to allow for such a possibility.

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Changes in Treatment and Severity of Multisystem Inflammatory Syndrome in Children: An EHR-based cohort study from the RECOVER program

Schuchard, J.; Thacker, D.; Webb, R.; Bailey, C.; Bennett, T. D.; Cogen, J. D.; Jhaveri, R.; Jone, P.-N.; Lee, G. M.; Maltenfort, M.; Mejias, A.; Rogerson, C. M.; Schulert, G. S.; Mendonca, E. A.; RECOVER consortium,

2022-10-21 pediatrics 10.1101/2022.10.19.22281256 medRxiv
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ObjectivesThe purpose of this study was to examine how the treatment and severity of multisystem inflammatory syndrome in children (MIS-C) has changed over more than two years of the COVID-19 pandemic in the United States. MethodsElectronic health record data were retrieved from the PEDSnet network as part of the NIH Researching COVID to Enhance Recovery (RECOVER) Initiative. The study included data for children ages 0 to 20 years hospitalized for MIS-C from March 1, 2020 through July 20, 2022. Descriptive statistics for MIS-C treatments and laboratory results were computed for three time periods of interest: March 1, 2020 - May 31, 2021 (pre-Delta); June 1 - December 31, 2021 (primarily Delta); January 1 - July 20, 2022 (primarily Omicron). Standardized differences measured the effect size of the difference between Omicron and pre-Omicron cohorts. ResultsThe study included 946 children with a diagnosis of MIS-C. The largest differences in the Omicron period compared to prior years were decreases in the percentage of children with abnormal troponin (effect size = 0.40), abnormal lymphocytes (effect size = 0.33), and intensive care unit (ICU) visits (effect size = 0.34). There were small decreases in the Omicron period for the majority of treatments and abnormal laboratory measurements examined, including infliximab, anticoagulants, furosemide, aspirin, IVIG without steroids, echocardiograms, mechanical ventilation, platelets, ferritin, and sodium. ConclusionsThis study provides the first evidence that the severity of MIS-C declined in the first half of the year 2022 relative to prior years of the COVID-19 pandemic in the United States. Article SummaryUsing electronic health record data for 946 children, we found evidence that the severity of MIS-C declined during the first half of the year 2022. Whats Known on This SubjectThe clinical management of multisystem inflammatory syndrome in children (MIS-C) has commonly included intravenous immune globulin, steroids, and non-steroidal anti-inflammatory agents. Many children with MIS-C have required intravenous fluids, inotropes and vasopressors, and in some cases, mechanical ventilation. What This Study AddsRecent decreases in the percentage of children with MIS-C that have abnormal troponin, abnormal lymphocytes, or intensive care unit visits provide evidence that the severity of MIS-C has declined in the first half of the year 2022.

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Clinical Subphenotypes of Multisystem Inflammatory Syndrome in Children: An EHR-based cohort study from the RECOVER program

Rao, S.; Jing, N.; Liu, X.; Lorman, V.; Maltenfort, M.; Schuchard, J.; Wu, Q.; Tong, J.; Razzaghi, H.; Mejias, A.; Lee, G. M.; Pajor, N. M.; Schulert, G. S.; Thacker, D.; Jhaveri, R.; Christakis, D. A.; Bailey, L. C.; Forrest, C. B.; Chen, Y.

2022-09-27 pediatrics 10.1101/2022.09.26.22280364 medRxiv
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BackgroundMulti-system inflammatory syndrome in children (MIS-C) represents one of the most severe post-acute sequelae of SARS-CoV-2 infection in children, and there is a critical need to characterize its disease patterns for improved recognition and management. Our objective was to characterize subphenotypes of MIS-C based on presentation, demographics and laboratory parameters. MethodsWe conducted a retrospective cohort study of children with MIS-C from March 1, 2020 - April 30, 2022 and cared for in 8 pediatric medical centers that participate in PEDSnet. We included demographics, symptoms, conditions, laboratory values, medications and outcomes (ICU admission, death), and grouped variables into eight categories according to organ system involvement. We used a heterogeneity-adaptive latent class analysis model to identify three clinically-relevant subphenotypes. We further characterized the sociodemographic and clinical characteristics of each subphenotype, and evaluated their temporal patterns. FindingsWe identified 1186 children hospitalized with MIS-C. The highest proportion of children (44{middle dot}4%) were aged between 5-11 years, with a male predominance (61.0%), and non- Hispanic white ethnicity (40{middle dot}2%). Most (67{middle dot}8%) children did not have a chronic condition. Class 1 represented children with a severe clinical phenotype, with 72{middle dot}5% admitted to the ICU, higher inflammatory markers, hypotension/shock/dehydration, cardiac involvement, acute kidney injury and respiratory involvement. Class 2 represented a moderate presentation, with 4-6 organ systems involved, and some overlapping features with acute COVID-19. Class 3 represented a mild presentation, with fewer organ systems involved, lower CRP, troponin values and less cardiac involvement. Class 1 initially represented 51{middle dot}1% of children early in the pandemic, which decreased to 33{middle dot}9% from the pre-delta period to the omicron period. InterpretationMIS-C has a spectrum of clinical severity, with degree of laboratory abnormalities rather than the number of organ systems involved providing more useful indicators of severity. The proportion of severe/critical MIS-C decreased over time. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed and preprint articles from December 2019, to July 2022, for studies published in English that investigated the clinical subphenotypes of MIS-C using the terms "multi-system inflammatory syndrome in children" or "pediatric inflammatory multisystem syndrome" and "phenotypes". Most previous research described the symptoms, clinical characteristics and risk factors associated with MIS-C and how these differ from acute COVID-19, Kawasaki Disease and Toxic Shock Syndrome. One single-center study of 63 patients conducted in 2020 divided patients into Kawasaki and non-Kawasaki disease subphenotypes. Another CDC study evaluated 3 subclasses of MIS-C in 570 children, with one class representing the highest number of organ systems, a second class with predominant respiratory system involvement, and a third class with features overlapping with Kawasaki Disease. However, this study evaluated cases from March to July 2020, during the early phase of the pandemic when misclassification of cases as Kawasaki disease or acute COVID-19 may have occurred. Therefore, it is not known from the existing literature whether the presentation of MIS-C has changed with newer variants such as delta and omicron. Added value of this studyPEDSnet provides one of the largest MIS-C cohorts described so far, providing sufficient power for detailed analyses on MIS-C subphenotypes. Our analyses span the entire length of the pandemic, including the more recent omicron wave, and provide an update on the presentations of MIS-C and its temporal dynamics. We found that children have a spectrum of illness that can be characterized as mild (lower inflammatory markers, fewer organ systems involved), moderate (4-6 organ involvement with clinical overlap with acute COVID-19) and severe (higher inflammatory markers, critically ill, more likely to have cardiac involvement, with hypotension/shock and need for vasopressors). Implications of all the available evidenceThese results provide an update to the subphenotypes of MIS-C including the more recent delta and omicron periods and aid in the understanding of the various presentations of MIS-C. These and other findings provide a useful framework for clinicians in the recognition of MIS-C, identify factors associated with children at risk for increased severity, including the importance of laboratory parameters, for risk stratification, and to facilitate early evaluation, diagnosis and treatment.

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Coronavirus (COVID-19) infection in children at a specialist centre: outcome and implications of underlying high-risk comorbidities in a paediatric population

Issitt, R.; Booth, J.; Bryant, W.; Spiridou, A.; Taylor, A.; DuPre, P.; Ramnarayan, P.; Hartley, J.; Cortino Borja, M.; Moshal, K.; Dunn, H.; Hemingway, H.; Sebire, N.

2020-05-25 pediatrics 10.1101/2020.05.20.20107904 medRxiv
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BackgroundThere is evolving evidence of significant differences in severity and outcomes of coronavirus disease 2019 (COVID-19) in children compared to adults. Underlying medical conditions associated with increased risk of severe disease are based on adult data, but have been applied across all ages resulting in large numbers of families undertaking social shielding (vulnerable group). We conducted a retrospective analysis of children with suspected COVID-19 at a Specialist Childrens Hospital to determine outcomes based on COVID-19 testing status and underlying health vulnerabilities. MethodsRoutine clinical data were extracted retrospectively from the Institutions Electronic Health Record system and Digital Research Environment for patients with suspected and confirmed COVID-19 diagnoses. Data were compared between Sars-CoV-2 positive and negative patients (CoVPos / CoVNeg respectively), and in relation to presence of underlying health vulnerabilities based on Public Health England guidance. FindingsBetween 1st March and 15th May 2020, 166 children (<18 years of age) presented to a specialist childrens hospital with clinical features of possible COVID-19 infection. 65 patients (39.2%) tested positive for SARS-CoV-2 virus. CoVPos patients were older (median 9 [0.9 - 14] years vs median 1 [0.1 - 5.7.5] years respectively, p<0.001). There was a significantly reduced proportion of vulnerable cases (47.7% vs 72.3%, p=0.002), but no difference in proportion of vulnerable patients requiring ventilation (61% vs 64.3%, p = 0.84) between CoVPos and CoVNeg groups. However, a significantly lower proportion of CoVPos patients required mechanical ventilation support compared to CoVNeg patients (27.7 vs 57.4%, p<0.001). Mortality was not significantly different between CoVPos and CoVNeg groups (1.5 vs 4% respectively, p=0.67) although there were no direct COVID-19 related deaths in this highly preselected paediatric population. InterpretationCOVID-19 infection may be associated with severe disease in childhood presenting to a specialist hospital, but does not appear significantly different in severity to other causes of similar clinical presentations. In children presenting with pre-existing COVID-19 vulnerable medical conditions at a specialist centre, there does not appear to be significantly increased risk of either contracting COVID-19 or severe complications, apart from those undergoing chemotherapy, who are over-represented.

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Demographic and Outcome Characteristics of Children Hospitalized with Acute COVID-19 versus Multisystem Inflammatory Syndrome in Children in Canada

Farrar, D. S.; Moore Hepburn, C.; Drouin, O.; El Tal, T.; Morin, M.-P.; Berard, R. A.; King, M.; Laffin Thibodeau, M.; Haddad, E.; Scuccimarri, R.; Yeung, R. S. M.; Kakkar, F.; Morris, S. K.; Canadian Paediatric Surveillance Program COVID-19 Study Team,

2022-08-19 epidemiology 10.1101/2022.08.18.22278939 medRxiv
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Direct comparisons of pediatric hospitalizations for acute COVID-19 and multisystem inflammatory syndrome in children (MIS-C) can inform health system planning. While there were more hospitalizations and deaths from acute COVID-19 amongst Canadian children between March 2020-May 2021, MIS-C cases were more severe, requiring more intensive care and vasopressor support.

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Natural History of Prenatally Identified Children with 48,XXYY Syndrome in Infancy and Early Childhood

Nocon, K.; Swenson, K.; Bothwell, S.; Howell, S.; Davis, S.; Ikomi, C.; Ross, J.; Tartaglia, N.

2026-06-04 pediatrics 10.64898/2026.06.04.26353909 medRxiv
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Background: 48,XXYY syndrome is a rare sex chromosome aneuploidy (SCA) characterized by neurodevelopmental deficits and medical comorbidities. The limited information available in the literature is almost exclusively limited to postnatally diagnosed cases. This study aims to describe the early medical and developmental features of prenatally identified 48,XXYY infants, with comparisons to 47,XYY, 47,XXY cohorts, and typical populations, as well as previously reported postnatally diagnosed 48,XXYY cases. Methods: The eXtraordinarY Babies Study prospectively follows children prenatally identified to be at high risk for SCA with annual medical and neurodevelopmental evaluations. Data presented herein include the prevalence of medical conditions, developmental milestones, developmental and adaptive functioning assessment scores, and therapy utilization in participants confirmed to have 48,XXYY. Comparisons were made between this cohort and the typical population, infants with 47,XYY and 47,XXY also enrolled in the eXtraordinarY Babies Study, and a 2008 cohort of individuals postnatally identified 48,XXYY. Results: Infants with 48,XXYY exhibited a range of early medical features, including high rates of feeding and GI disorders (breastfeeding difficulties, gastroesophageal reflux, and eosinophilic esophagitis), allergic disorders (food allergies and environmental allergies), and hypotonia. Developmental and adaptive functioning scores indicated delays in motor, communication, and social domains, with nearly all infants receiving speech therapy, physical and/or occupational therapy. Comparisons with the 47,XYY and 47,XXY cohorts revealed more medical and developmental challenges in the 48,XXYY group, however there was variability and some overlap with both the general population and sex chromosome trisomy conditions. Additionally, comparison to the 2008 postnatally identified 48,XXYY cohort indicated that while prenatal diagnosis allowed for earlier intervention, developmental outcomes in the first years of life were similar between the two groups. Conclusions: 48,XXYY diagnosed prenatally facilitates early monitoring, anticipatory guidance, and proactive referrals for medical evaluations and intervention, given developmental delays and medical challenges are more common in infancy and early childhood compared to the general population and trisomy SCAs. These findings provide valuable insights for genetic counselors and healthcare providers, emphasizing the spectrum of medical and developmental findings and importance of early and proactive care to support individual outcomes. Prospective study of this prenatally identified cohort will provide important natural history and phenotypic variability in XXYY, as well as identification of predictors of health and developmental outcomes.

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COVID- 19 Infection in Children: Estimating Pediatric Morbidity and Mortality

Barton Forbes, M.; Mehta, K.; Kumar, K.; Lu, J.; Le Saux, N.; Sampson, M.; Robinson, J.

2020-05-08 pediatrics 10.1101/2020.05.05.20091751 medRxiv
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BACKGROUNDEstimates of pediatric morbidity and mortality from COVID-19 are vital for planning optimal use of human and material resources throughout this pandemic. METHODSGovernment websites from countries with minimum 1000 cases in adults and children on April 13, 2020 were searched to find the number of cases confirmed in children, the age range, and the number leading to hospitalization, intensive care unit (ICU) admission or death. A systematic literature search was performed April 13, 2020 to find additional data from cases series. RESULTSData on pediatric cases were available from government websites for 23 of the 70 countries with minimum 1000 cases by April 13, 2020. Of 424 978 cases in these 23 countries, 8113 (1.9%) occurred in children. Nine publications provided data from 4251 cases in 4 additional countries. Combining data from the websites and the publications, 330 of 2361 cases required admission (14%). The ICU admission rate was 2.2 % of confirmed cases (44 of 2031) and 7.2% of admitted children (23 of 318). Death was reported for 15 cases. CONCLUSIONChildren accounted for 1.9% of confirmed cases. The true incidence of pediatric infection and disease will only be known once testing is expanded to individuals with less severe or no symptoms. Admission rates vary from 0.3 to 10% of confirmed cases (presumably varying with the threshold for testing) with about 7% of admitted children requiring ICU care. Death is rare in middle and high income countries.

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EHR-based Case Identification of Pediatric Long COVID: A Report from the RECOVER EHR Cohort

Botdorf, M.; Dickinson, K.; Lorman, V.; Razzaghi, H.; Marchesani, N.; Rao, S.; Rogerson, C.; Higginbotham, M. J.; Mejias, A.; Salyakina, D.; Thacker, D.; Dandachi, D.; Christakis, D.; Taylor, E.; Schwenk, H.; Morizono, H.; Cogen, J.; Pajor, N. M.; Jhaveri, R.; Forrest, C.; Bailey, C.; RECOVER Consortium,

2024-05-23 pediatrics 10.1101/2024.05.23.24307492 medRxiv
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ObjectiveLong COVID, marked by persistent, recurring, or new symptoms post-COVID-19 infection, impacts childrens well-being yet lacks a unified clinical definition. This study evaluates the performance of an empirically derived Long COVID case identification algorithm, or computable phenotype, with manual chart review in a pediatric sample. This approach aims to facilitate large-scale research efforts to understand this condition better. MethodsThe algorithm, composed of diagnostic codes empirically associated with Long COVID, was applied to a cohort of pediatric patients with SARS-CoV-2 infection in the RECOVER PCORnet EHR database. The algorithm classified 31,781 patients with conclusive, probable, or possible Long COVID and 307,686 patients without evidence of Long COVID. A chart review was performed on a subset of patients (n=651) to determine the overlap between the two methods. Instances of discordance were reviewed to understand the reasons for differences. ResultsThe sample comprised 651 pediatric patients (339 females, Mage = 10.10 years) across 16 hospital systems. Results showed moderate overlap between phenotype and chart review Long COVID identification (accuracy = 0.62, PPV = 0.49, NPV = 0.75); however, there were also numerous cases of disagreement. No notable differences were found when the analyses were stratified by age at infection or era of infection. Further examination of the discordant cases revealed that the most common cause of disagreement was the clinician reviewers tendency to attribute Long COVID-like symptoms to prior medical conditions. The performance of the phenotype improved when prior medical conditions were considered (accuracy = 0.71, PPV = 0.65, NPV = 0.74). ConclusionsAlthough there was moderate overlap between the two methods, the discrepancies between the two sources are likely attributed to the lack of consensus on a Long COVID clinical definition. It is essential to consider the strengths and limitations of each method when developing Long COVID classification algorithms.

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Medical Findings in Infants Prenatally Identified with Sex Chromosome Trisomy in Year One of Life

Tartaglia, N.; Davis, S.; Howell, S.; Bothwell, S.; Nocon, K.; Kowal, K.; Ikomi, C.; Keene, A.; Reynolds, V.; Berglund, A.; Ross, J.

2024-07-10 pediatrics 10.1101/2024.07.10.24310206 medRxiv
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BACKGROUND AND OBJECTIVESex chromosome trisomies (SCT), including XXY, XYY, and XXX syndromes, have been historically underdiagnosed. Noninvasive prenatal cell-free DNA screening has significantly increased identification of these conditions, leading to a need for pediatric care for a growing population of newborns with SCT. Our goal was to analyze and compare perinatal features, medical diagnoses, and physical features in infants with prenatal identification of SCT conditions through the first year of life. METHODSThe eXtraordinarY Babies Study is an ongoing, prospective natural history study of prenatally identified children with SCT conducted by interdisciplinary teams in Colorado and Delaware. Participants were enrolled prior to 12 months of age and had pregnancy, birth, medical histories, and physical exams completed by board-certified pediatricians at 2, 6, and/or 12-month visits. Descriptive statistics were followed by comparisons between SCT groups using t-tests or ANOVA, Fisher exact, and correlations between medical features with alpha of 0.05. Relative risks were calculated compared to general population rates. RESULTS327 infants were included in the analysis (XXY=195, XXX=79, XYY=53). Major congenital anomalies were rare (1.7%). Relative risk compared to general population was elevated for breastfeeding difficulties (51.7%;RR 2.7), positional torticollis (28.2%;RR 7.2), eczema (48.0%;RR 3.5), food allergies (19.3%;RR 2.4), constipation requiring intervention (33.9%;RR 7.6), small cardiac septal defects (7.7%;RR 17.2), and structural renal abnormalities (4.4%;RR 9.7). Inpatient hospitalization was required for 12.4%, with 59.5% of hospitalizations attributable to respiratory infections. DISCUSSIONThese findings of medical conditions with a higher prevalence can inform anticipatory guidance and medical management for pediatricians caring for infants with SCT. Article SummaryMedical findings in largest cohort of prenatally identified infants with XXY, Trisomy X, and XYY from birth to 12 months and implications for pediatric care. Whats Known on This SubjectOne in [~]500 individuals have an extra X or Y chromosome, or sex chromosome trisomy (SCT). Prenatal screening is now routinely identifying SCT, however there are few studies to guide perinatal and infant care for these individuals. What This Study AddsThis prospective observational study presents medical features for 327 infants with prenatally identified SCT from birth through the first year of life. Results identify where proactive screenings and/or interventions may be warranted for infants with SCT.

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Access to Care in PANS: A Survey of Families Journeys to and Experiences with IVIG Treatment

Calaprice, D.; Moon, C.; Helvick, M.; Harvey, C.; Tang, A.; Aguirre, K.; Hunt, J.; Terreri, R.; Whitty, C.; Fitzgerald, M.

2025-12-30 pediatrics 10.64898/2025.12.23.25342929 medRxiv
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BackgroundPediatric Acute-Onset Neuropsychiatric Syndrome (PANS) is characterized by abrupt-onset neuropsychiatric symptoms, often infection- or immune-triggered. Intravenous immunoglobulin (IVIG) is recommended by expert guidelines for select cases, yet insurance denials and high out-of-pocket costs have been major barriers to access. MethodsWe surveyed 60 caregivers and/or adult PANS patients who pursued IVIG therapy, collecting data on insurance experiences, treatment protocols, financial strategies, and patient/caregiver quality of life (QoL) before and after treatment. ResultsMost patients (88%) eventually received IVIG; 10% were still in pursuit, and 2% discontinued trying. Insurance approval without appeal occurred in only 18%, while many families faced multiple denials and appeals. Insurance approvals were more expeditious for patients with comorbidities for which IVIG is typically covered; among those receiving IVIG for PANS alone, only 5% were treated within a month of the doctors order (compared to 38% of those receiving IVIG for comorbidities as well as PANS) and 14% waited [&ge;]9 months before treatment began. Financial strain was routine: one-third of families without substantial coverage (i.e., insurance that covered >=70% of expenses) reported extreme stress (10/10), 58% borrowed money, and 21% sold major assets. Even families with substantial insurance coverage commonly depleted savings or took on additional work. Prior to IVIG, patient Quality of Life (QoL) ratings were poor (means 2.1-2.8 across domains), with over one-third selecting the lowest possible ratings. During the six months following IVIG initiation, mean scores rose to 6.2-6.8, with over 60% reporting "good" to "exceedingly good" outcomes. Caregivers reported parallel gains, with family QoL ratings rising from 2.4-4.0 pre-treatment to 5.7-6.6 post-treatment. ConclusionsFamilies pursuing IVIG for PANS faced prolonged delays, repeated denials, and extreme financial strain, often resorting to loans, asset sales, and additional work. Despite these burdens, IVIG was associated with marked improvements in quality of life for both patients and caregivers, underscoring the treatments potential benefits and the urgent need for more equitable access.

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Multisystem inflammatory syndrome in European White children - study of 274 cases

Ludwikowska, K. M.; Okarska-Napierala, M.; Dudek, N.; Tracewski, P.; Kusa, J.; Piwonski, K.; Afelt, A.; Cysewski, D.; Biela, M.; Werner, B.; Jackowska, T.; Suski, C.; Kursa, M. B.; Kuchar, E.; Szenborn, L.

2021-03-31 pediatrics 10.1101/2021.03.30.21254584 medRxiv
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BackgroundDespite the growing literature on multisystem inflammatory syndrome in children (MIS-C), the data in European White population is limited. Our aim was to capture MIS-C emergence in Poland (central Europe) and to describe its characteristics with a focus on severity determinants. MethodsPatients who met the MIS-C definition (fever, multiorgan failure, inflammation, and proven SARS-CoV-2 infection or contact) were reported retrospectively and prospectively in an online survey. Study definitions fulfilment was automatically evaluated by a dedicated software. For the assessment of univariate relationships, either directed or divided by sex, age, or disease severity, we used the test for two categorical variables and the Kruskal-Wallis test for categorical-continuous variable pairs. FindingsThe analysis involved 274 children, 62.8% boys, median age 8.8 years. Besides one Asian, all were European White. Merely 23 (8.4%) required paediatric intensive care treatment (PICU). They were older (11.2 vs. 8.4 years), and at hospital admission had higher respiratory rate (30 v. 20/minute), lower systolic blood pressure (89 vs. 100 mmHg), prolonged capillary refill time (40% vs. 11%), and decreased consciousness (22% vs. 5%). Teenage boys had more common cardiac involvement (fraction 25.9% vs. 14.7%) and macrophage activation syndrome (31.0% vs. 15.2%) than others. Boys were also more often hospitalised in PICU with age (from median 11.2 years to 9.1). InterpretationThe severity of MIS-C is not as uniform as it seemed, ethnicity and sex may affect MIS-C phenotype. Management might not be universally applicable and should rather be adjusted to the specific population. FundingPSP: 501-D402-20-0006100

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Healthcare utilization following SARS-CoV-2 infection in children and adolescents with chronic conditions: An EHR-based Cohort Study from the RECOVER Program

Pajor, N. M.; Lorman, V.; Razzaghi, H.; Case, A.; Prahalad, P.; Bose-Brill, S.; Wu, Q.; Chen, Y.; Block, J. P.; Patel, P. B.; Rao, S.; Mejias, A.; Thacker, D.; Jhaveri, R.; Bailey, L. C.; Forrest, C. B.; Lee, G. M.

2022-07-09 pediatrics 10.1101/2022.07.08.22276768 medRxiv
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BackgroundChronic medical conditions are a risk factor for moderate or severe COVID-19 in children, but little is known about post-acute sequelae of SARS-CoV-2 infection (PASC) in children with chronic medical conditions (CMCs). To understand whether SARS-CoV-2 infection led to potential exacerbation of underlying chronic disease in children, we explored whether children with CMCs had increased healthcare utilization in the post-acute (28 days after infection) period compared to children with CMCs without SARS-CoV-2 infection. MethodsWe conducted a retrospective, matched-cohort study using electronic health record data collected from 8 pediatric health care systems participating in the PEDSnet network. We included children <21 years of age with a wide array of chronic conditions, defined by the presence of diagnostic codes, who were diagnosed with COVID-19 between March 1, 2020 and February 28, 2022. Cohort entry was defined by presence of a positive SARS-CoV-2 PCR test (polymerase chain reaction or antigen) or diagnostic codes for COVID-19, PASC or MIS-C. A comparison cohort of patients testing negative or without these conditions was matched using a stratified propensity score model and exact matching on age group, race/ethnicity, institution, test location, and month of cohort entry. A negative binomial model was used to examine our primary outcome: composite and setting-specific (inpatient, outpatient, ED) utilization rate ratios between the positive and comparison cohorts. Secondary outcomes included time to first utilization in the post-acute period, and utilization stratified by severity at cohort entry. ResultsWe identified 748,692 patients with at least one chronic condition, 78,744 of whom met inclusion criteria for the COVID-19 cohort. 96% of patients from the positive cohort were matched. Cohorts were well-balanced for chronic condition clusters, total number of conditions, time since first diagnosis, baseline utilization, cohort entry period, age, sex, race/ethnicity and test location. We found that among children with chronic medical conditions, those with COVID-19 had higher healthcare utilization than those with no recorded COVID-19 diagnosis or positive test, with utilization rate ratio of 1.21 (95% CI: 1.18-1.24). The utilization was highest for inpatient care with utilization rate ratio of 2.03 (95% CI: 1.85-2.23) but the utilization was increased across all settings. Hazard ratios estimated in time-to-first-utilization analysis mirrored these results. Patients with severe or moderate acute COVID-19 illness had greater increases in utilization in all settings than those with mild or asymptomatic disease. ConclusionsWe found that care utilization in all settings was increased following COVID-19 in children with chronic medical conditions in the post-acute period, particularly in the inpatient setting. Increased utilization was correlated with more severe COVID-19. Additional research is needed to better understand the reasons for higher care utilization by studying condition-specific outcomes in children with chronic disease.

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Quantifying the Spectrum of Early Motor and Language Milestones in Sex Chromosome Trisomy

Thompson, T.; Bothwell, S.; Janusz, J.; Wilson, R.; Howell, S.; Davis, S.; Swenson, K.; Martin, S.; Kowal, K.; Ikomi, C.; Despradel, M.; Ross, J.; Tartaglia, N.

2024-08-19 pediatrics 10.1101/2024.08.16.24312065 medRxiv
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Background and objectivesSex chromosome trisomy (SCT) is a common chromosomal abnormality associated with increased risks for early developmental delays and neurodevelopmental disorders later in childhood. Our objective was to quantify the spectrum of early developmental milestones in SCT. We hypothesized later milestone achievement in SCT than the general population. MethodsData were collected as part of the eXtraordinarY Babies Study, a prospective natural history of developmental and health trajectories in a prenatally identified sample of infants with SCT. Parent reported, clinician-validated, early motor and language milestones were collected at 2, 6, 12, 18, 24, and 36-months. Age distributions of milestone achievement were compared with normative data. ResultsIn all SCT conditions, compared with normative data, there was increased variability and a later median age of skill development across multiple gross motor and expressive language milestones. Results also show a significant amount of overlap with the general pediatric population, suggesting that for many children with prenatally identified SCT, early milestones present within, or close to, the expected timeline. ConclusionsAs increasing numbers of infants with prenatal SCT diagnoses present at pediatric practices, we provide an evidence-based schedule of milestone achievement in SCT as a tool for pediatricians and families. Detailed data on SCT milestones can support clinical interpretation of milestone achievement. Increased variability and later median age of milestone acquisition in SCT compared to norms support consideration of all infants with SCT as high risk.

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Pediatric critical COVID-19 and mortality in a multinational cohort

Gonzalez-Dambrauskas, S.; Vasquez-Hoyos, P.; Camporesi, A.; Cantillano, E. M.; Dallefeld, S.; Dominguez-Rojas, J.; Francoeur, C.; Gurbanov, A.; Mazzillo-Vega, L.; Shein, S.; Yock-Corrales, A.; Karsies, T.; Critical Coronavirus and Kids Epidemiological (CAKE) Study Investigators,

2021-08-23 pediatrics 10.1101/2021.08.20.21262122 medRxiv
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ObjectivesTo understand the international epidemiology of critical pediatric COVID-19 and compare presentation, treatments, and outcomes of younger (<2 years) and older (>2 years) children. DesignProspective, observational study from April 1 to December 31, 2020 SettingInternational multicenter study from 55 sites from North America, Latin America, and Europe. ParticipantsPatients <19 years old hospitalized with critical COVID-19 Interventionsnone Main outcomes measuredClinical course, treatments, and outcomes were compared between younger and older children. Multivariable logistic regression was used to calculate adjusted odds ratios (aOR) for hospital mortality. Results557 subjects (median age, 8 years; 24% <2 years) were enrolled from 55 sites (63% Latin American). Half had comorbidities. Younger children had more respiratory findings (56% vs 44%), viral pneumonia (45% vs 29%), and treatment with invasive ventilation (50% vs 37). Gastrointestinal (28% vs 69%) or mucocutaneous (16% vs 44%) findings, vasopressor requirement (44% vs 60%), and MIS-C (15% vs 40%) were less common in younger children. Hospital mortality was 10% overall but 15% in younger children (odds ratio 1.89 [95%CI 1.05-3.39]). When adjusted for age, sex, region, and illness severity, mortality-associated factors included cardiac (aOR 2.6; 95%CI 1.07-6.31) or pulmonary comorbidities (aOR 4.4; 95%CI 1.68-11.5), admission hypoxemia (aOR 2.33; 95%CI 1.24-4.37), and lower respiratory symptoms (aOR 2.83; 95%CI 1.49-5.39). Gastrointestinal (aOR 0.49; 95%CI 0.26-0.92) or mucocutaneous symptoms (aOR 0.31; 95%CI 0.15-0.64), treatment with intravenous immune globulin (aOR 0.33; 95%CI 0.17-0.65), and MIS-C (aOR 0.26; 95%CI 0.11-0.64) were associated with lower mortality. ConclusionsWe identified age-related differences in presentation and mortality for critical pediatric COVID-19 that should prompt more attention to improving management in younger children, especially in developing countries. Table of Contents SummaryThis is a multinational study describing critical pediatric COVID-19 clinical spectrum and related mortality in high and low-middle income countries during 2020. Whats known on this subjectPediatric critical illness due to COVID-19 is uncommon and have lower mortality compared to adults when hospitalized. While larger cohorts are from high-income countries (HICs), studies including data from low-middle-income countries (LMICs) remain scarce. What this study addsIn our multinational cohort of critical pediatric COVID-19, we identified higher mortality than previously reported and age-related disease patterns. Children <2 years old had more respiratory disease and higher mortality, and older children had more non-pulmonary disease and better outcomes.

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Population-based assessment of neurodevelopmental and mental health diagnoses among pediatric patients with Turner Syndrome: A PEDSnet study

Hutaff-Lee, C.; Jolliffe, M.; Swenson, K.; Wakeman, H.; Swain, D.; Furniss, A.; Nokoff, N.; Hansen-Moore, J.; Ikomi, C.; Bamba, V.; Lean, R. E.; Leonard, S.; Davis, S.

2025-06-20 pediatrics 10.1101/2025.06.17.25329800 medRxiv
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Individuals with Turner syndrome (TS) are known to be at increased risk for neurodevelopmental disorders (NDD) and mental health (MH) conditions, but data from large, population-based pediatric samples remain limited. We examined the prevalence of NDD and MH diagnoses among youth with TS (N = 2,145) compared to matched female controls (N = 8,580) across six U.S. pediatric health systems. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using generalized estimating equations. Youth with TS had significantly higher odds of an NDD diagnosis (24.2% vs. 11.9%; OR 2.37, 95% CI 2.11-2.67), particularly for speech-language, motor, learning, and attentional disorders. Increased odds were also observed for autism spectrum disorder (ASD) and intellectual developmental disorder (IDD), though these remained relatively uncommon. In contrast, MH diagnoses, such as anxiety and mood disorders, were not more prevalent in TS compared to controls (17.3% vs. 18.5%; OR 0.92, 95% CI 0.81-1.05). These findings support the need for proactive neurodevelopmental screening in TS and raise important questions about the recognition and documentation of MH conditions in this population. Additional research is warranted to understand whether MH symptoms are underdiagnosed in youth with TS or emerge later in development.

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Evaluating mainstreaming in pediatric immunology: an optimal model of care

DeBortoli, E.; Clinch, T.; Vaz-Goncalves, L.; Burbury, L.; Jeppesen, M.; Pinzon Charry, A.; Melo, M.; Sullivan, A.; Hunter, M.; Peake, J.; McInerney-Leo, A.; McNaughton, P.; Yanes, T.

2026-02-26 genetic and genomic medicine 10.64898/2026.02.24.26347043 medRxiv
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PurposeWhile genomic testing is integral to pediatric inborn errors of immunity (IEI) care, few studies have examined strategies to support its optimal delivery. This study aimed to characterize a pediatric IEI cohort and assess the impact of implementing a mainstream model-of-care (MoC). Materials/MethodsComprehensive chart audit was conducted for patients ([&le;]18y) who received IEI genomic testing in Queensland, Australia, from 2017-2025. Descriptive analyses captured demographic and clinical characteristics, genomic testing and results, and management outcomes. Inferential analyses assessed changes in genomic practices pre-MoC (<2021) and post-MoC ([&ge;]2021). Results322 patients met eligibility criteria (n=481 genomic test). Diagnostic yield (27.6%) varied by testing indication, with the highest rate among phagocytic defects (n=4/4;100%) and severe combined immunodeficiency (n=8/10;80%). Very-early-onset inflammatory bowel disease had the lowest diagnostic yield (n=3/68;4.4%), prompting changes to testing criteria. Molecular diagnosis resulted in management changes for 90.5% patients. Genomic testing was widely used pre-MoC (n=251 genomic tests). All outcomes significantly improved pre-and post-MoC (p<0.05): duplicate testing decreased (13.9% to 0%); variants of uncertain significance reduced (37.7% to 7.1%); informed consent documentation increased (70.5% to 88.4%); and diagnostic yield increased (16.2% to 27.4%). ConclusionTargeted interventions are needed to support delivery of genomic testing and strengthen service effectiveness.

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Multisystemic inflammatory syndrome following COVID-19 mRNA vaccine in children: a national post-authorization pharmacovigilance study

Ouldali, N.; Bagheri, H.; Salvo, F.; Antona, D.; Pariente, A.; Leblanc, C.; Tebacher, M.; Micallef, J.; Levy, C.; Cohen, R.; Javouhey, E.; Bader-Meunier, B.; Ovaert, C.; Renolleau, S.; Hengten, V.; Kone-Paut, I.; Deschamps, N.; De Pontual, L.; Iriart, X.; Gras-Le Guen, C.; Angoulvant, F.; Belot, A.

2022-01-18 pediatrics 10.1101/2022.01.17.22269263 medRxiv
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ImportanceMultisystem inflammatory syndrome in children (MIS-C) is the most severe life-threatening clinical entity associated with pediatric SARS-CoV-2 infection. Whether COVID-19 mRNA vaccine can induce this complication in children is unknown. ObjectiveTo assess the risk of hyper-inflammatory syndrome following COVID-19 mRNA vaccine in children. Design, Setting, and ParticipantsPost-authorization national population-based surveillance using the French enhanced pharmacovigilance surveillance system for COVID-19 vaccines. All cases of suspected hyper-inflammatory syndrome following COVID-19 mRNA vaccine in 12- 17-year-old children between June 15th, 2021 and January 1st, 2022, were reported. Each case was assessed for WHO MIS-C criteria. Causality assessment followed 2019 WHO recommendations. ExposureCOVID-19 mRNA vaccine. Main Outcome and MeasuresThe main outcome was the reporting rate of post-vaccine hyper-inflammatory syndrome per 1,000,000 COVID-19 mRNA vaccine doses in 12-17-year-old children. This reporting rate was compared to the MIS-C rate per 1,000,000 12-17-year-old children infected by SARS-CoV-2. Secondary outcomes included the comparison of clinical features between post-vaccine hyper-inflammatory syndrome and post SARS-CoV-2 MIS-C. ResultsFrom June 2021 to January 2022, 8,113,058 COVID-19 mRNA vaccine doses were administered to 4,079,234 12-17-year-old children. Among them, 9 presented a multisystemic hyper-inflammatory syndrome. All cases fulfilled MIS-C WHO criteria. Main clinical features included male predominance (8/9, 89%), cardiac involvement (8/9, 89%), digestive symptoms (7/9, 78%), coagulopathy (5/9, 54%), cytolytic hepatitis (4/9, 46%), and shock (3/9, 33%). 3/9 (33%) required intensive care unit transfer, and 2/9 (22%) hemodynamic support. All cases recovered. Only three cases had evidence of previous SARS-CoV-2 infection. The reporting rate was 1.1 (95%CI [0.5; 2.1]) per 1,000,000 doses injected. As a comparison, 113 MIS-C (95%CI [95; 135]) occurred per 1,000,000 12-17-year-old children infected by SARS-CoV-2. Clinical features (inflammatory parameters, cytopenia) slightly differed from post-SARS-CoV-2 MIS-C, along with short-term outcomes (less PICU transfer than MIS-C). Conclusion and RelevanceVery few cases of hyper-inflammatory syndromes with multi-organ involvement occurred following COVID-19 mRNA vaccine in 12-17-year-old children. The low reporting rate of this syndrome, compared to the rate of MIS-C among same age children infected by SARS-CoV-2, supports the benefit of SARS-CoV-2 vaccination in children. Further studies are required to explore specific pathways of this entity compared to post-SARS-CoV-2 MIS-C. Key pointsO_ST_ABSQuestionC_ST_ABSIs COVID-19 mRNA vaccine in 12-17-year-old children associated with subsequent multisystemic hyper-inflammatory syndrome? FindingsThe French national pharmacovigilance system identified 9 children with a hyper-inflammatory syndrome with multi-organ involvement following COVID-19 mRNA vaccination (reporting rate 1.1 [0.5; 2.1] per 1,000,000 doses), of which only three had evidence of previous SARS-CoV-2 infection. All cases fulfilled WHO definition for MIS-C, but clinical and immunological features, along with short-term outcomes, slightly differed from classical post SARS-CoV-2 MIS-C. MeaningVery rare cases of hyper-inflammatory syndrome can occur following COVID-19 mRNA vaccine in 12-17-year-old children. The very low rate of this entity, compared to classical post-SARS-CoV-2 MIS-C, supports the benefit of SARS-CoV-2 vaccination in children.

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Overweight and Obesity as Predictors of Post-acute Sequelae of SARS-Cov-2 Infection: Findings from the RECOVER Initiative

ZHOU, T.; Zhang, B.; Zhang, D.; Wu, Q.; Becich, M.; Blecker, S. B.; Chen, J.; Chilukuri, N.; Chrischilles, E. A.; Chu, H.; Corsino, L.; Geary, C. R.; Hornig, M.; Kim, S.; Liebovitz, D. M.; Lorman, V.; Lu, Y.; Luo, C.; Morizono, H.; Mosa, A. S. M.; Pajor, N. M.; Rao, S.; Razzaghi, H.; Suresh, S.; Tedla, Y. G.; Vance Utset, L.; Wang, Y.; Williams, D. A.; Gage Witvliet, M.; Mangarelli, C.; Jhaveri, R.; Forrest, C.; Chen, Y.

2024-06-14 pediatrics 10.1101/2024.06.12.24308868 medRxiv
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IMPORTANCEObesity increases the severe COVID-19 risk. Whether obesity is associated with an increased risk of post-acute sequelae of SARS-Cov-2 infection (PASC) among pediatrics, independent of its impacts on acute infection severity, is unclear. OBJECTIVETo quantify the association between body mass index (BMI) status before SARS-CoV-2 infection and pediatric PASC risk, controlling for acute infection severity. DESIGNRetrospective cohort study occurred from March 2020 to May 2023, with a minimal follow-up of 179 days. SETTINGTwenty-six US childrens hospitals. PARTICIPANTSIndividuals aged 5-20 years with SARS-CoV-2 infection. EXPOSURESElevated BMI status assessed before infection. MAIN OUTCOMES AND MEASURESTo identify PASC, we first used the ICD-10-CM code specific for post-COVID-19 conditions, and a second approach used clusters of symptoms and conditions that constitute the PASC phenotype. BMI was assessed within 18 months before infection; the measure closest to the index date was selected. Relative risk (RR) for BMI-PASC association was quantified by Poisson regression models, adjusting for sociodemographic, acute COVID severity, and other clinical factors. RESULTSAmong the 172136 participants included, the median age of BMI assessment and cohort entry were 12.8 and 13.2 years, 1402 (0.8%) were identified as having PASC with the ICD-10-CM code, and 74317 (43.2%) had [&ge;]1 incident occurrence of PASC symptoms and conditions. Compared with participants with a healthy weight, those who had overweight, obesity, and severe obesity had 4.7% (RR, 1.047; 95% CI, 0.868-1.263), 25.4% (RR, 1.254; 95% CI, 1.064-1.478) and 42.1% (RR, 1.421; 95% CI, 1.253-1.611) higher risk of PASC when identified using the diagnosis code, respectively. The risk for any occurrences of PASC symptoms and conditions also increased in overweight (RR, 1.030; 95% CI, 0.982-1.080), obesity (RR, 1.108; 95% CI, 1.064-1.154), and severe obesity (RR, 1.174; 95% CI, 1.138-1.213), and that for total incident occurrences increased, too, in overweight (RR, 1.053; 95% CI, 1.000-1.109), obesity (RR, 1.137; 95% CI, 1.088-1.188), and severe obesity (RR, 1.182; 95% CI, 1.142-1.223). CONCLUSIONS AND RELEVANCEElevated BMI was associated with a significantly increased PASC risk in a dose-dependent manner. The biological mechanisms for this association should be investigated in future research. Key PointsO_ST_ABSQuestionC_ST_ABSDo children, adolescents, and young adults with overweight and obesity have increased risk of developing post-acute sequelae of SARS-Cov-2 infection (PASC)? FindingsOverweight, obesity, and severe obesity were associated with significantly increased risk of pediatric PASC. Compared with pediatrics with body mass index in the healthy range, those who were overweight, obesity, or severely obesity had an increased incidence of 4.7%, 25.4%, and 42.1% of PASC, respectively. MeaningOverweight and obesity are important risk factors for pediatric PASC. The biological mechanisms for this association should be investigated in the future research.