Multisystem Inflammatory Syndrome in Children (MIS-C) is a new phenomenon reported worldwide with temporal association with Covid-19. The objective of this paper is to evaluate reported cases in children and adolescents. From 1726 papers, 35 documented papers related to MIS-C cases identified 783 individual cases of MIS-C between March-June 2020; with 55% being male ( n = 435) and a median age of 8.6 years (IQR, 7–10 years; range 3 months–20 years). Patients with MIS-C were noted to have a high frequency of gastrointestinal symptoms (71%) including abdominal pain (34%) and diarrhea (27%). Cough and respiratory distress were reported in 4.5% and 9.6% cases respectively. Blood parameters showed neutrophilia in 345/418 (83%) of cases and a high CRP in 587/626 (94%). 362/619 (59%) cases were SARS-CoV-2 infection positive (serology or PCR) however only 41% demonstrated pulmonary changes on chest imaging. Severity of illness was high with 68% cases requiring intensive care admission; 63% requiring inotropic support; 244/783 (28%) cases needing some form of respiratory support (138 mechanically ventilated), and 31 required extra-corporeal membrane oxygenation. Treatment strategies included intravenous immunoglobulin (63%) and intravenous steroids (44%). 29 cases received Infliximab, 47 received IL1 (interleukin) receptor antagonist, and 47 received IL6-receptor antagonist. 12/783 (1.5%) children died. In summary, a higher incidence of gastrointestinal symptoms were noted in MIS-C. In contrast to acute Covid-19 infection in children, MIS-C appears to be a condition of higher severity with 68% of cases having required critical care support.

SummaryBackgroundLung delivery of plasmid DNA encoding the CFTR gene complexed with a cationic liposome is a potential treatment option for patients with cystic fibrosis. We aimed to assess the efficacy of non-viral CFTR gene therapy in patients with cystic fibrosis.MethodsWe did this randomised, double-blind, placebo-controlled, phase 2b trial in two cystic fibrosis centres with patients recruited from 18 sites in the UK. Patients (aged ≥12 years) with a forced expiratory volume in 1 s (FEV1) of 50–90% predicted and any combination of CFTR mutations, were randomly assigned, via a computer-based randomisation system, to receive 5 mL of either nebulised pGM169/GL67A gene–liposome complex or 0·9% saline (placebo) every 28 days (plus or minus 5 days) for 1 year. Randomisation was stratified by % predicted FEV1 (<70 vs ≥70%), age (<18 vs ≥18 years), inclusion in the mechanistic substudy, and dosing site (London or Edinburgh). Participants and investigators were masked to treatment allocation. The primary endpoint was the relative change in % predicted FEV1. The primary analysis was per protocol. This trial is registered with ClinicalTrials.gov, number NCT01621867.FindingsBetween June 12, 2012, and June 24, 2013, we randomly assigned 140 patients to receive placebo (n=62) or pGM169/GL67A (n=78), of whom 116 (83%) patients comprised the per-protocol population. We noted a significant, albeit modest, treatment effect in the pGM169/GL67A group versus placebo at 12 months' follow-up (3·7%, 95% CI 0·1–7·3; p=0·046). This outcome was associated with a stabilisation of lung function in the pGM169/GL67A group compared with a decline in the placebo group. We recorded no significant difference in treatment-attributable adverse events between groups.InterpretationMonthly application of the pGM169/GL67A gene therapy formulation was associated with a significant, albeit modest, benefit in FEV1 compared with placebo at 1 year, indicating a stabilisation of lung function in the treatment group. Further improvements in efficacy and consistency of response to the current formulation are needed before gene therapy is suitable for clinical care; however, our findings should also encourage the rapid introduction of more potent gene transfer vectors into early phase trials.FundingMedical Research Council/National Institute for Health Research Efficacy and Mechanism Evaluation Programme.

Data show that children are less severely affected with SARS-Covid-19 than adults; however, there have been a small proportion of children who have been critically unwell. In this systematic review, we aimed to identify and describe which underlying comorbidities may be associated with severe SARS-CoV-2 disease and death. The study protocol was in keeping with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A total of 1726 articles were identified of which 28 studies fulfilled the inclusion criteria. The 28 studies included 5686 participants with confirmed SARS-CoV-2 infection ranging from mild to severe disease. We focused on the 108 patients who suffered from severe/critical illness requiring ventilation, which included 17 deaths. Of the 108 children who were ventilated, the medical history was available for 48 patients. Thirty-six of the 48 patients (75%) had documented comorbidities of which 11/48 (23%) had pre-existing cardiac disease. Of the 17 patients who died, the past medical history was reported in 12 cases. Of those, 8/12 (75%) had comorbidities. Conclusion: Whilst only a small number of children suffer from COVID-19 disease compared to adults, children with comorbidities, particularly pre-existing cardiac conditions, represent a large proportion of those that became critically unwell. What is Known:• Children are less severely affected by SARS-CoV-2 than adults.• There are reports of children becoming critically unwell with SARS-CoV-2 and requiring intensive care. What is New:• The majority of children who required ventilation for SARS-CoV-2 infection had underlying comorbidities.• The commonest category of comorbidity in these patients was underlying cardiac disease.

Effect of the new SARS-CoV-2 variant B.1.1.7 on children and young people The clinical impact of the new SARS-CoV-2 lineage B.1•1.7 on children and young people (aged 18 years or younger) regarding acute respiratory COVID-19 is yet to be fully defined. Media reports of increases in admissions to hospital and more serious illness in children and young people have resulted in public confusion and implicated the B.1.1.7 variant as a more pathogenic infection within this group. 1,2 This uncertainty has necessitated a public statement from the Royal College of Paediatrics and Child Health. 3

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