Italian good practice recommendations on management of persons with Long-COVID.

A significant number of people, following acute SARS-CoV-2 infection, report persistent symptoms or new symptoms that are sustained over time, often affecting different body systems. This condition, commonly referred to as Long-COVID, requires a complex clinical management. In Italy new health facilities specifically dedicated to the diagnosis and care of Long-COVID were implemented. However, the activity of these clinical centers is highly heterogeneous, with wide variation in the type of services provided, specialistic expertise and, ultimately, in the clinical care provided. Recommendations for a uniform management of Long-COVID were therefore needed. Professionals from different disciplines (including general practitioners, specialists in respiratory diseases, infectious diseases, internal medicine, geriatrics, cardiology, neurology, pediatrics, and odontostomatology) were invited to participate, together with a patient representative, in a multidisciplinary Panel appointed to draft Good Practices on clinical management of Long-COVID. The Panel, after extensive literature review, issued recommendations on 3 thematic areas: access to Long-COVID services, clinical evaluation, and organization of the services. The Panel highlighted the importance of providing integrated multidisciplinary care in the management of patients after SARS-CoV-2 infection, and agreed that a multidisciplinary service, one-stop clinic approach could avoid multiple referrals and reduce the number of appointments. In areas where multidisciplinary services are not available, services may be provided through integrated and coordinated primary, community, rehabilitation and mental health services. Management should be adapted according to the patient's needs and should promptly address possible life-threatening complications. The present recommendations could provide guidance and support in standardizing the care provided to Long-COVID patients.

A proof-of-concept study on the genomic evolution of Sars-Cov-2 in molnupiravir-treated, paxlovid-treated and drug-naïve patients.

Little is known about SARS-CoV-2 evolution under Molnupiravir and Paxlovid, the only antivirals approved for COVID-19 treatment. By investigating SARS-CoV-2 variability in 8 Molnupiravir-treated, 7 Paxlovid-treated and 5 drug-naïve individuals at 4 time-points (Days 0-2-5-7), a higher genetic distance is found under Molnupiravir pressure compared to Paxlovid and no-drug pressure (nucleotide-substitutions/site mean±Standard error: 18.7 × 10-4 ± 2.1 × 10-4 vs. 3.3 × 10-4 ± 0.8 × 10-4 vs. 3.1 × 10-4 ± 0.8 × 10-4, P = 0.0003), peaking between Day 2 and 5. Molnupiravir drives the emergence of more G-A and C-T transitions than other mutations (P = 0.031). SARS-CoV-2 selective evolution under Molnupiravir pressure does not differ from that under Paxlovid or no-drug pressure, except for orf8 (dN > dS, P = 0.001); few amino acid mutations are enriched at specific sites. No RNA-dependent RNA polymerase (RdRp) or main proteases (Mpro) mutations conferring resistance to Molnupiravir or Paxlovid are found. This proof-of-concept study defines the SARS-CoV-2 within-host evolution during antiviral treatment, confirming higher in vivo variability induced by Molnupiravir compared to Paxlovid and drug-naive, albeit not resulting in apparent mutation selection.

The Relationship Between Pediatric Gut Microbiota and SARS-CoV-2 Infection.

This is the first study on gut microbiota (GM) in children affected by coronavirus disease 2019 (COVID-19). Stool samples from 88 patients with suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and 95 healthy subjects were collected (admission: 3-7 days, discharge) to study GM profile by 16S rRNA gene sequencing and relationship to disease severity. The study group was divided in COVID-19 (68), Non-COVID-19 (16), and MIS-C (multisystem inflammatory syndrome in children) (4). Correlations among GM ecology, predicted functions, multiple machine learning (ML) models, and inflammatory response were provided for COVID-19 and Non-COVID-19 cohorts. The GM of COVID-19 cohort resulted as dysbiotic, with the lowest α-diversity compared with Non-COVID-19 and CTRLs and by a specific ß-diversity. Its profile appeared enriched in Faecalibacterium, Fusobacterium, and Neisseria and reduced in Bifidobacterium, Blautia, Ruminococcus, Collinsella, Coprococcus, Eggerthella, and Akkermansia, compared with CTRLs (p < 0.05). All GM paired-comparisons disclosed comparable results through all time points. The comparison between COVID-19 and Non-COVID-19 cohorts highlighted a reduction of Abiotrophia in the COVID-19 cohort (p < 0.05). The GM of MIS-C cohort was characterized by an increase of Veillonella, Clostridium, Dialister, Ruminococcus, and Streptococcus and a decrease of Bifidobacterium, Blautia, Granulicatella, and Prevotella, compared with CTRLs. Stratifying for disease severity, the GM associated to "moderate" COVID-19 was characterized by lower α-diversity compared with "mild" and "asymptomatic" and by a GM profile deprived in Neisseria, Lachnospira, Streptococcus, and Prevotella and enriched in Dialister, Acidaminococcus, Oscillospora, Ruminococcus, Clostridium, Alistipes, and Bacteroides. The ML models identified Staphylococcus, Anaerostipes, Faecalibacterium, Dorea, Dialister, Streptococcus, Roseburia, Haemophilus, Granulicatella, Gemmiger, Lachnospira, Corynebacterium, Prevotella, Bilophila, Phascolarctobacterium, Oscillospira, and Veillonella as microbial markers of COVID-19. The KEGG ortholog (KO)-based prediction of GM functional profile highlighted 28 and 39 KO-associated pathways to COVID-19 and CTRLs, respectively. Finally, Bacteroides and Sutterella correlated with proinflammatory cytokines regardless disease severity. Unlike adult GM profiles, Faecalibacterium was a specific marker of pediatric COVID-19 GM. The durable modification of patients' GM profile suggested a prompt GM quenching response to SARS-CoV-2 infection since the first symptoms. Faecalibacterium and reduced fatty acid and amino acid degradation were proposed as specific COVID-19 disease traits, possibly associated to restrained severity of SARS-CoV-2-infected children. Altogether, this evidence provides a characterization of the pediatric COVID-19-related GM.

COVID-19 in Infants Less than 3 Months: Severe or Not Severe Disease?

Compared to adults, severe or fatal COVID-19 disease is much less common in children. However, a higher risk for progression has been reported in infants. Different pediatric COVID-19 severity scores are reported in the literature. METHODS: Subjects under 90 days of age admitted to 35 Italian institutions for COVID-19 were included. The severity of COVID-19 was scored as mild/moderate or severe/critical following the classification reported in the literature by Venturini, Dong, Kanburoglu, and Gale. To assess the diagnostic accuracy of each classification system, we stratified all enrolled patients developing a posteriori severity score based on clinical presentation and outcomes and then compared all different scores analyzed. RESULTS: We included 216 infants below 90 days of age. The most common symptom was fever, followed by coryza, poor feeding, cough, and gastrointestinal manifestations. According to Venturini, Dong, Kanburoglu, and Gale's severity scores, 18%, 6%, 4.2%, and 29.6% of infants presented with severe/critical disease, respectively. A correlation analysis between these four scores and the a posteriori severity score assigned to all enrolled subjects was performed, and a crescent strength of correlation from Gale (R = 0.355, p < 0.001) to Venturini (R = 0.425, p < 0.001), Dong (R = 0.734, p < 0.001), and Kanburoglu (R = 0.859, p < 0.001) was observed. CONCLUSIONS: The percentage of infants with severe COVID-19 varies widely according to the score systems. A unique clinical score should be designed for neonates and infants with COVID-19.

Long-Term Cardiovascular Outcome in Children with MIS-C Linked to SARS-CoV-2 Infection-An Italian Multicenter Experience.

MIS-C is a multisystem inflammatory syndrome that is characterized by multi-organ failure and cardiac involvement. The aim of this study was to describe the long-term cardiovascular outcome in a cohort of MIS-C pediatric patients, who were admitted to two Italian Pediatric Referral Centers. Sixty-seven patients (mean age 8.7 ± 4.7 years, male 60%) were included; 65 (97%) of them showed cardiac involvement. All of the patients completed one month of the follow-up, and 47% completed 1 year of it. ECG abnormalities were present in 65% of them, arrhythmias were present in 9% of them during an acute phase and it disappeared at the point of discharge or later. Pericarditis were detected in 66% of them and disappeared after 6 months. Coronaritis was observed in 35% of the children during an acute phase, and there were no more instances at the 1-year point. An LV dysfunction was present in 65% of the patients at the beginning of the study, with them having a full recovery at the point of discharge and thereafter. Elevated values of the NTproBNP and hsTp were initially detected, which progressively decreased and normalized at the points of discharge and FU. The CMR at the point of FU, there was a presence of long-term myocardial scars in 50% of the patients that were tested. No deaths that were caused by MIS-C during the FU were recorded. Cardiac involvement in MIS-C patients is almost the rule, but the patients' clinical course was satisfactory, and no additional events or sequelae were observed apart from there being long-term myocardial scars in 50% of the patients that underwent CMR.

Epidemiological characterization of SARS-CoV-2 variants in children over the four COVID-19 waves and correlation with clinical presentation.

Since the start of SARS-CoV-2 pandemic, children aged ≤ 12 years have always been defined as underrepresented in terms of SARS-CoV-2 infections' frequency and severity. By correlating SARS-CoV-2 transmission dynamics with clinical and virological features in 612 SARS-CoV-2 positive patients aged ≤ 12 years, we demonstrated a sizeable circulation of different SARS-CoV-2 lineages over the four pandemic waves in paediatric population, sustained by local transmission chains. Age < 5 years, highest viral load, gamma and delta clades positively influence this local transmission. No correlations between COVID-19 manifestations and lineages or transmission chains are seen, except for a negative correlation between B.1.1.7 and hospitalization.

The Relationship Between Pediatric Gut Microbiota and SARS-CoV-2 Infection

This is the first study on gut microbiota (GM) in children affected by coronavirus disease 2019 (COVID-19). Stool samples from 88 patients with suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and 95 healthy subjects were collected (admission: 3–7 days, discharge) to study GM profile by 16S rRNA gene sequencing and relationship to disease severity. The study group was divided in COVID-19 (68), Non–COVID-19 (16), and MIS-C (multisystem inflammatory syndrome in children) (4). Correlations among GM ecology, predicted functions, multiple machine learning (ML) models, and inflammatory response were provided for COVID-19 and Non–COVID-19 cohorts. The GM of COVID-19 cohort resulted as dysbiotic, with the lowest α-diversity compared with Non–COVID-19 and CTRLs and by a specific β-diversity. Its profile appeared enriched in Faecalibacterium, Fusobacterium, and Neisseria and reduced in Bifidobacterium, Blautia, Ruminococcus, Collinsella, Coprococcus, Eggerthella, and Akkermansia, compared with CTRLs (p < 0.05). All GM paired-comparisons disclosed comparable results through all time points. The comparison between COVID-19 and Non–COVID-19 cohorts highlighted a reduction of Abiotrophia in the COVID-19 cohort (p < 0.05). The GM of MIS-C cohort was characterized by an increase of Veillonella, Clostridium, Dialister, Ruminococcus, and Streptococcus and a decrease of Bifidobacterium, Blautia, Granulicatella, and Prevotella, compared with CTRLs. Stratifying for disease severity, the GM associated to “moderate” COVID-19 was characterized by lower α-diversity compared with “mild” and “asymptomatic” and by a GM profile deprived in Neisseria, Lachnospira, Streptococcus, and Prevotella and enriched in Dialister, Acidaminococcus, Oscillospora, Ruminococcus, Clostridium, Alistipes, and Bacteroides. The ML models identified Staphylococcus, Anaerostipes, Faecalibacterium, Dorea, Dialister, Streptococcus, Roseburia, Haemophilus, Granulicatella, Gemmiger, Lachnospira, Corynebacterium, Prevotella, Bilophila, Phascolarctobacterium, Oscillospira, and Veillonella as microbial markers of COVID-19. The KEGG ortholog (KO)–based prediction of GM functional profile highlighted 28 and 39 KO-associated pathways to COVID-19 and CTRLs, respectively. Finally, Bacteroides and Sutterella correlated with proinflammatory cytokines regardless disease severity. Unlike adult GM profiles, Faecalibacterium was a specific marker of pediatric COVID-19 GM. The durable modification of patients’ GM profile suggested a prompt GM quenching response to SARS-CoV-2 infection since the first symptoms. Faecalibacterium and reduced fatty acid and amino acid degradation were proposed as specific COVID-19 disease traits, possibly associated to restrained severity of SARS-CoV-2–infected children. Altogether, this evidence provides a characterization of the pediatric COVID-19–related GM.

One Year of Lung Ultrasound in Children with SARS-CoV-2 Admitted to a Tertiary Referral Children's Hospital: A Retrospective Study during 2020-2021.

During the COVID-19 pandemic, the lung ultrasound (LU) turned out to be a pivotal tool to study the lung involvement in the adult population, but the same was not well evaluated in children. We detected the LU patterns through an integrated approach with clinical-laboratory features in children hospitalized for COVID-19 in relation to the temporal trend of the Italian epidemic. We conducted a retrospective study which took place at a pediatric tertiary hospital from 15 March 2020 to 15 March 2021. We compared the characteristics of the initial phase of the first COVID-19 year-in the spring and summer (15 March-30 September 2020)-and those of the second phase-in the autumn and winter (1 October 2020-15 March 2021). Twenty-eight patients were studied both in the first and in the second phase of the first COVID-19 year. The disease severity score (DSS) was significantly greater in the second phase (p = 0.015). In the second phase of the first COVID-19 year, we detected a more significant occurrence of the following LU features than in the first phase: the irregular pleural line (85.71% vs. 60.71%; p = 0.035), the B-lines (89.29% vs. 60%; p = 0.003) and the several but non-coalescent B-lines (89.29% vs. 60%; p = 0.003). The LU score correlated significantly with the DSS, with a moderate relationship (r = 0.51, p < 0.001). The combined clinical, laboratory and ultrasound approaches might be essential in the evaluation of pulmonary involvement in children affected by COVID-19 during different periods of the pandemic.

Safety of Monoclonal Antibodies in Children Affected by SARS-CoV-2 Infection.

Monoclonal antibody therapies for COVID-19 have been frequently used in adults, whereas there are little data regarding the safety or efficacy of monoclonal antibody treatments in pediatric patients affected by COVID-19. We report our experience in the administration of mAb as a treatment for SARS-CoV-2 infection in children aged from 24 days to 18 years old.

SARS-CoV-2 infection as possible downstream disease precipitator in autoantibody-positive insulin-dependent diabetes mellitus: a case report.

BACKGROUND: SARS-CoV-2 causes lesions, in addition to lung, in endocrine organs such as the pancreas through ACE2 receptor. Recently the relationship between SARS-CoV-2 exposition and the incidence or evolution of clinical autoimmune diabetes has attracted the attention of diabetologists. CASE PRESENTATION: We report the analysis of the clinical history of a child diagnosed for insulin-dependent diabetes mellitus (Type 1 diabetes) at the time a paucisymptomatic COVID-19 infection occurred, followed by well-controlled metabolic status. As opposite to previous findings SARS-CoV2 did not cause ketosis and ketoacidosis. Polydipsia was reported a few months and weight loss 4 weeks before SARS- CoV-2 infection suggesting that SARS-CoV-2 could not be the trigger of Type 1 diabetes in this patient. CONCLUSIONS: SARS-CoV-2 in this patient was an unexpected event in the course of disease. We advance the hypothesis that the SARS-CoV-2 infection, even if paucisymptomatic could have acted in the present case report as a hypothetical downstream precipitating factor; whilst the inciting triggering event of the autoimmune disease, as confirmed by the presence of circulating autoantibodies, could have occurred even before, as generally assumed for this category of disorders. The precipitating mechanism could have been the acute interaction between virus and the ACE receptor on the beta cells, at the time that hyperglycemia and glycosuria were ascertained, and HbA1c levels confirmed a metabolic dysregulation over the previous 3 months in absence of ketoacidosis.

Factors Associated With Severe Gastrointestinal Diagnoses in Children With SARS-CoV-2 Infection or Multisystem Inflammatory Syndrome.

Importance: Severe gastrointestinal (GI) manifestations have been sporadically reported in children with COVID-19; however, their frequency and clinical outcome are unknown. Objective: To describe the clinical, radiological, and histopathologic characteristics of children with COVID-19 presenting with severe GI manifestations to identify factors associated with a severe outcome. Design, Setting, and Participants: A multicenter retrospective cohort study (February 25, 2020, to January 20, 2021) enrolled inpatient and outpatient children (aged <18 years) with acute SARS-CoV-2 infection, confirmed by positive real-time reverse-transcriptase-polymerase chain reaction on nasopharyngeal swab or fulfilling the US Centers for Disease Control and Prevention criteria for multisystem inflammatory syndrome in children (MIS-C). The study was conducted by pediatricians working in primary care or hospitals in Italy participating in the COVID-19 Registry of the Italian Society of Pediatric Infectious Diseases. Main Outcomes and Measures: The occurrence of severe GI manifestations, defined by a medical and/or radiological diagnosis of acute abdomen, appendicitis (complicated or not by perforation and/or peritonitis), intussusception, pancreatitis, abdominal fluid collection, and diffuse adenomesenteritis requiring surgical consultation, occurring during or within 4 to 6 weeks after infection with SARS-CoV-2 infection. Logistic regression was used to estimate odds ratios (ORs) with 95% CIs of factors potentially associated with severe outcomes. Results: Overall, 685 children (386 boys [56.4%]; median age, 7.3 [IQR, 1.6-12.4] years) were included. Of these children, 628 (91.7%) were diagnosed with acute SARS-CoV-2 infection and 57 (8.3%) with MIS-C. The presence of GI symptoms was associated with a higher chance of hospitalization (OR, 2.64; 95% CI, 1.89-3.69) and intensive care unit admission (OR, 3.90; 95% CI, 1.98-7.68). Overall, 65 children (9.5%) showed severe GI involvement, including disseminated adenomesenteritis (39.6%), appendicitis (33.5%), abdominal fluid collection (21.3%), pancreatitis (6.9%), or intussusception (4.6%). Twenty-seven of these 65 children (41.5%) underwent surgery. Severe GI manifestations were associated with the child's age (5-10 years: OR, 8.33; 95% CI, 2.62-26.5; >10 years: OR, 6.37; 95% CI, 2.12-19.1, compared with preschool-age), abdominal pain (adjusted OR [aOR], 34.5; 95% CI, 10.1-118), lymphopenia (aOR, 8.93; 95% CI, 3.03-26.3), or MIS-C (aOR, 6.28; 95% CI, 1.92-20.5). Diarrhea was associated with a higher chance of adenomesenteritis (aOR, 3.13; 95% CI, 1.08-9.12) or abdominal fluid collection (aOR, 3.22; 95% CI, 1.03-10.0). Conclusions and Relevance: In this multicenter cohort study of Italian children with SARS-CoV-2 infection or MIS-C, 9.5% of the children had severe GI involvement, frequently associated with MIS-C. These findings suggest that prompt identification may improve the management of serious complications.

SARS-CoV-2 and Pre-Tamponade Pericardial Effusion. Could Sotos Syndrome Be a Major Risk Factor?

Pericarditis with pericardial effusion in SARS CoV-2 infection is a well-known entity in adults. In children and adolescents, only a few cases have been reported. Here, we present here a case of a 15-year-old girl affected by Sotos syndrome with pre-tamponed pericardial effusion occurred during SARS-CoV-2 infection. A possible relation between SARS-CoV-2 pericarditis and genetic syndromes, as a major risk factor for the development of severe inflammation, has been speculated. We emphasize the importance of active surveillance by echocardiograms when SARS-CoV-2 infection occurs in combination with a genetic condition.

Cardiac Manifestations in Children with SARS-COV-2 Infection: 1-Year Pediatric Multicenter Experience.

Since the spread of COVID-19, pediatric patients were initially considered less affected by SARS-COV-2, but current literature reported subsets of children with multisystem inflammatory syndrome (MIS-C). This study aims to describe the cardiac manifestation of SARS-COV-2 infection in a large cohort of children admitted to two Italian pediatric referral centers. Between March 2020 and March 2021, we performed a cardiac evaluation in 294 children (mean age 9 ± 5.9 years, male 60%) with active or previous SARS-COV-2 infection. Twenty-six showed ECG abnormalities: 63 repolarization anomalies, 13 Long QTc, five premature ventricular beats, two non-sustained ventricular tachycardia, and one atrial fibrillation. In total, 146 patients underwent cardiac biomarkers: NT-proBNP was elevated in 57, troponin in 34. An echocardiogram was performed in 98, showing 54 cardiac anomalies: 27 left-ventricular dysfunction, 42 pericarditis, 16 coronaritis. MIS-C was documented in 46 patients (mean age 9 ± 4.8 years, male 61%) with cardiac manifestations in 97.8%: 27 ventricular dysfunctions, 32 pericarditis, 15 coronaritis, 3 arrhythmias. All patients recovered, and during follow-up, no cardiac anomalies were recorded. Our experience showed that cardiac involvement is not rare in children with SARS-COV-2, and occurred in almost all patients with MIS-C. However, patients' recovery is satisfactory and no additional events were reported during FU.

Post-discharge telephonic follow-up of pediatric patients affected by SARS-CoV2 infection in a single Italianpediatric COVID center: a safe and feasible way to monitor children after hospitalization.

BACKGROUND: SARS-CoV-2 infection in children is often non severe and in the majority of cases does not require long term hospitalization, nevertheless it is burdened with social issues and managing difficulties. To our knowledge there is no literature on telephonic follow up in pediatric patients with positive PCR for SARS-CoV-2 on rhino-pharyngeal swab after discharge. The aim of the study is to describe our experience in a telephonic follow up which can allow early and safe discharge from hospital while keeping the patients under close clinical monitoring. MATERIALS AND METHODS: Sixty-five children were admitted for SARS-CoV-2 infection at Bambino Gesù Pediatric Hospital COVID Center from 16th March to 3rd July. We monitored through a telephonic follow-up, using a specific survey, the patients discharged still presenting a positive PCR for SARS-CoV-2. We checked if any symptoms occurred at home until recovery, defined as two consecutive negative PCR for SARS-CoV-2 on rhino-pharyngeal swabs. RESULTS: During the follow up 7 patients had mild and self-limited symptoms related to SARS-CoV-2 infection, while 2 patients were re-hospitalized. One patient had Multisystem Inflammatory Syndrome in Children (MIS-C), the other patient had an increase in troponin and D-dimers. We also monitored the average time of viral shedding, resulting in a median duration of 28 days. CONCLUSION: Our experience describes the daily telephonic follow up as safe in pediatric patients discharged with positive PCR. As a matter of fact it could avoid long term hospitalization and allow to promptly re-hospitalize children with major complications such as MIS-C.

Virological and immunological features of SARS-COV-2 infected children with distinct symptomatology.

BACKGROUND: Although SARS-CoV-2 immunizations have started in most countries, children are not currently included in the vaccination programs; thus, it remains crucial to define their anti-SARS-CoV-2 immune response in order to minimize the risk for other epidemic waves. This study sought to provide a description of the virology ad anti-SARS-CoV-2 immunity in children with distinct symptomatology. METHODS: Between March and July 2020, we recruited 15 SARS-CoV-2 asymptomatic (AS) and 51 symptomatic (SY) children, stratified according to WHO clinical classification. We measured SARS-CoV-2 viral load using ddPCR and qPCR in longitudinally collected nasopharyngeal swab samples. To define anti-SARS-CoV-2 antibodies, we measured neutralization activity and total IgG load (DiaSorin). We also evaluated antigen-specific B and CD8+T cells, using a labeled S1+S2 protein and ICAM expression, respectively. Plasma protein profiling was performed with Olink. RESULTS: Virological profiling showed that AS patients had lower viral load at diagnosis (p = .004) and faster virus clearance (p = .0002) compared with SY patients. Anti-SARS-CoV-2 humoral and cellular response did not appear to be associated with the presence of symptoms. AS and SY patients showed similar titers of SARS-CoV-2 IgG, levels of neutralizing activity, and frequency of Ag-specific B and CD8+ T cells, whereas pro-inflammatory plasma protein profile was found to be associated with symptomatology. CONCLUSION: We demonstrated the development of anti-SARS-CoV-2 humoral and cellular response with any regard to symptomatology, suggesting the ability of both SY and AS patients to contribute toward herd immunity. The virological profiling of AS patients suggested that they have lower virus load associated with faster virus clearance.

Virological and immunological features of SARS-CoV-2-infected children who develop neutralizing antibodies.

As the global COVID-19 pandemic progresses, it is paramount to gain knowledge on adaptive immunity to SARS-CoV-2 in children to define immune correlates of protection upon immunization or infection. We analyzed anti-SARS-CoV-2 antibodies and their neutralizing activity (PRNT) in 66 COVID-19-infected children at 7 (±2) days after symptom onset. Individuals with specific humoral responses presented faster virus clearance and lower viral load associated with a reduced in vitro infectivity. We demonstrated that the frequencies of SARS-CoV-2-specific CD4+CD40L+ T cells and Spike-specific B cells were associated with the anti-SARS-CoV-2 antibodies and the magnitude of neutralizing activity. The plasma proteome confirmed the association between cellular and humoral SARS-CoV-2 immunity, and PRNT+ patients show higher viral signal transduction molecules (SLAMF1, CD244, CLEC4G). This work sheds lights on cellular and humoral anti-SARS-CoV-2 responses in children, which may drive future vaccination trial endpoints and quarantine measures policies.

Hyperinflammation in Two Severe Acute Respiratory Syndrome Coronavirus 2-Infected Adolescents Successfully Treated With the Interleukin-1 Inhibitor Anakinra and Glucocorticoids.

Background: In severe acute respiratory syndrome-related coronavirus (SARS-CoV-2) critically ill adults, hyperinflammation plays a key role in disease progression. The clinical manifestations of SARS-CoV-2 infection among children are much less severe compared with adult patients and usually associated with a good prognosis. However, hyperinflammation in SARS-CoV-2-infected pediatric patients has been described as pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 or as Kawasaki-like disease but is still little known, and optimal management has to be defined. The World Health Organization (WHO) on the 15th of May 2020 has developed a preliminary case definition for multisystem inflammatory disorder in children and adolescents with coronavirus disease 2019 (COVID-19) and stated for an urgent need to collect data on this condition. Here, we report two adolescent patients affected by COVID-19 presenting with multisystem inflammatory disorder, 3-4 weeks after the first symptoms of SARS-CoV-2 infection, treated with the interleukin-1 receptor antagonist anakinra and glucocorticoids with good clinical response. Cases: We report two patients chronically ill appearing, with high fever, severe gastrointestinal involvement, and increased biomarkers of inflammation onset 3-4 weeks after paucisymptomatic SARS-CoV-2 infection. They had no lung involvement, but abdominal ultrasound and CT scan showed thickening of the bowel wall. SARS-CoV-2 PCR was positive on ileum biopsy in both patients, whereas it was negative on other common sampled sites. They have been admitted to the pediatric intensive care unit and have been treated with a combination of anakinra 6-8 mg/kg/day i.v. and a standard dose of methylprednisolone 2 mg/kg/day in addition to lopinavir/ritonavir 400 mg q12h and low molecular weight heparin 100 UI/kg q12h with good clinical response.