COVID-19 in pediatric kidney transplantation: The Improving Renal Outcomes Collaborative

The humoral immune response to the BNT 162B2 vaccine in pediatrics on renal replacement therapy

INTRODUCTION

Since the start of the COVID-19 pandemic, data published on the immunogenicity of the SARS-CoV-2 BNT 162B2 vaccine in pediatric patients receiving renal replacement therapy are scant. Our primary objective is to study this population's humoral immune response to the COVID-19 vaccine.

METHODS

Pediatric kidney transplant recipients (PKTRs) and hemodialysis recipients (HR) at our center who received two doses of the SARS-CoV-2 BNT 162B2 vaccine were included. Transplant and HR who had PCR-positive COVID-19 infections during the study, regardless of their vaccine status, were also included. SARS-CoV-2 anti-spike protein (S1/S2) IgG was measured after the second dose of the vaccine and after any PCR-positive COVID-19 infection as routine clinical practice. Data on demographics, induction, maintenance immunosuppressants, type of transplant, and posttransplant or dialysis duration were included.

RESULTS

Of the 61 patients included, 19 were dialysis recipients who received two doses of vaccine without subsequent infection (HV), and 42 were kidney transplant recipients. All dialysis patients and 33 (78.6%) transplant recipients received two doses of the SARS-CoV-2 BNT 162b2 vaccine. A total of 33.3% (11/33) of the transplant recipients who received vaccination developed COVID-19 infection (KTH) at a median time of 13 days after the second dose of vaccine. Nine transplant patients had pure COVID-19 infection without vaccination (KTI). The seroconversion rate in the HV group was 94.7% (18/19) compared to 50% (11/22) in the kidney transplant vaccine recipients who did not develop subsequent COVID-19 infection (KTV) (p < .001). The median S1/S2 IgG titers for the HV group were 400 AU/mL versus 15 AU/mL in the KTV group (p < .0001). There was no significant difference in the duration of the test from the second dose of the vaccine between HV and KTV (55 vs. 33.5 days, p = .095). The KTH had higher titers than KTV group (370 vs. 15 p < .0001). The median duration of the test after vaccination in the vaccine group and those with hybrid immunity was similar (35 vs. 33.5 days, p = .2).There were no clear predictors for seroconversion in the PKTRs. Natural infection alone was as good as the vaccine in eliciting humoral immune response.

CONCLUSION

The humoral immune response to two doses of the SARS-CoV-2 BNT 162B2 vaccine in PKTRs without subsequent COVID-19 infection is suboptimal compared to that in hemodialysis recipients and in PKTRs with hybrid immunity from both infection and vaccination.

COVID-19 disease among children and young adults enrolled in the North American Pediatric Renal Trials and Collaborative Studies registry

BACKGROUND

Coronavirus disease of 2019 (COVID-19) has disproportionately affected adults with kidney disease. Data regarding outcomes among children with kidney disease are limited. The North American Pediatric Renal Trials Collaborative Studies Registry (NAPRTCS) has followed children with chronic kidney disease (CKD) since 1987 at 87 participating centers. This study aimed to evaluate the impact of COVID-19 among participants enrolled in the three arms of the registry: CKD, dialysis, and transplant.

METHODS

This was a retrospective cohort study of COVID-19 among participants in the NAPRTCS CKD, dialysis, and transplant registries from 2020 to 2022. Where appropriate, t-tests, chi-square analyses, and univariate logistic regression were used to evaluate the data.

RESULTS

The cohort included 1505 NAPRTCS participants with recent data entry; 260 (17%) had documented COVID-19. Infections occurred in all three registry arms, namely, 10% (n = 29) in CKD, 11% (n = 67) in dialysis, and 26% (n = 164) in transplant. The majority of participants (75%) were symptomatic. Hospitalizations occurred in 17% (n = 5) of participants with CKD, 27% (n = 18) maintenance dialysis participants, and 26% (n = 43) of transplant participants. Fourteen percent (n = 4) of CKD participants and 10% (n = 17) of transplant participants developed acute kidney injury (AKI), and a total of eight participants (one CKD, seven transplant) required dialysis initiation. Among transplant participants with moderate to severe illness, 40-43% developed AKI and 29-40% required acute dialysis. There were no reported deaths.

CONCLUSIONS

COVID-19 was documented in 17% of active NAPRTCS participants. While there was no documented mortality, the majority of participants were symptomatic, and a quarter required hospitalization.

Impact of Respiratory Viral Infections in Transplant Recipients

Respiratory viral infections (RVIs) are among the leading cause of morbidity and mortality in pediatric hematopoietic stem cell transplant (HCT) and solid organ transplant (SOT) recipients. Transplant recipients remain at high risk for super imposed bacterial and fungal pneumonia, chronic graft dysfunction, and graft failure as a result of RVIs. Recent multicenter retrospective studies and prospective studies utilizing contemporary molecular diagnostic techniques have better delineated the epidemiology and outcomes of RVIs in pediatric transplant recipients and have advanced the development of preventative vaccines and treatment interventions in this population. In this review, we will define the epidemiology and outcomes of RVIs in SOT and HSCT recipients, describe the available assays for diagnosing a suspected RVI, highlight evolving management and vaccination strategies, review the risk of donor derived RVI in SOT recipients, and discuss considerations for delaying transplantation in the presence of an RVI.

Non-fatal outcomes of COVID-19 disease in pediatric organ transplantation associates with down-regulation of senescence pathways

This is a cross-sectional study examining kinetics and durability of immune response in children with solid organ transplants (SOTs) who had COVID-19 disease between November 2020 through June 2022, who were followed for 60-days at a single transplant center. Blood was collected between 1-14 (acute infection), and 15-60 days of a positive PCR (convalescence). SOT children with peripheral blood mononuclear cells (PBMC) cryopreserved before 2019 were non-infected controls (ctrls). PBMCs stimulated with 15-mer peptides from spike protein and anti-CD49d/anti-CD28. Testing done included mass cytometry, mi-RNA sequencing with confirmatory qPCR. 38 children formed the study cohort, 10 in the acute phase and 8 in the convalescence phase. 20 subjects were non-infected controls. Two subjects had severe disease. Subjects in the acute and convalescent phases were different subjects. The median age and tacrolimus level at blood draw was not significantly different. There was no death, and no subject was lost to follow-up. During acute infection CD57 expression was low in NKT, Th17 effector memory, memory Treg, CD4-CD8-, and γδT cells (p = 0.01, p = 0.04, p = 0.03, p = 0.03, p = 0.004 respectively). The frequencies of NK and Th2 effector memory cells increased (p = 0.01, p = 0.02) during acute infection. Non-switched memory B and CD8 central memory cell frequencies were decreased during acute infection (p = 0.02; p = 0.02), but the decrease in CD8 central memory cells did not persist. CD4-CD8- and CD14 monocyte frequencies increased during recovery (p = 0.03; p = 0.007). Our observations suggest down regulation of CD57 with absence of NK cell contraction protect against death from COVID-19 disease in children with SOTs.

COVID-19 in Children with Chronic Kidney Disease; Does it Differ Much?

BACKGROUND

COVID-19 is known to have a mild course in children, however more data on pediatric chronic kidney disease (CKD) is needed. We aimed to assess the incidence and severity of COVID-19 in pediatric CKD patients.

METHODS

A questionnaire including demographics, COVID-19 history, symptoms, and vaccination status was applied to patients with CKD. We also retrospectively reviewed the presentation and outcomes of SARS-CoV-2 infection in this patient group from March 2020 to December 2021.

RESULTS

220 patients were included, 48 were found to have experienced COVID-19. There was no significant difference regarding age, gender, underlying kidney disease, CKD stage, dialysis status, type or number of immunosuppressive medications, and glomerular filtration rate between patients with and without COVID-19. Most were infected by a household member (43.8%) and during outpatient or inpatient care (18.8%). Four (8.3%) were asymptomatic, and 43 (89.6%) had mild infection. Severe COVID-19 was observed in only one patient. Eleven (22.9%) patients with COVID-19 were previously vaccinated. Acute kidney injury was detected in 4 (8.3%); as stage 1 in all. Median follow-up after COVID-19 was 4.6 months. All patients fully recovered, and no renal disease flare or death was observed.

CONCLUSIONS

Although the vaccination rate was low in our cohort, the majority of the children with COVID-19 showed a mild course. Along with the vaccination, general precautions seemed to be successful for this population.

A Scoping Review on Learning Health Networks Available in Pediatric Surgical Specialties

BACKGROUND

Learning health networks (LHN) are consortia of institutions that collaborate and embrace the elements of the learning health system (LHS), including quality improvement, education, research, and stakeholder involvement. Their ultimate goal is rapid information dissemination in clinical care. Pediatric surgical specialties perform unique yet high-impact procedures that could benefit from LHN, thereby improving surgical outcomes and care through LHS approaches. Consequently, health system leaders should be aware of LHN and their importance in enhancing surgical care and improving outcomes. This scoping review aims to map and characterize the existing LHN applied in pediatric surgical specialties.

METHODS

A systematic literature search was performed on Medline, EMBASE, and Scopus up to June 2022, with an update search conducted in May 2023. Additionally, Google Scholar, ProQuest and inquiry from topic experts were used for cross-referencing relevant review articles to identify grey literature. This scoping review was conducted and reported according to the PRISMA-scoping review extension.

RESULTS

A total of 56 publications for 19 LHN were identified and included in this scoping review. Out of 19 identified LHN in pediatric surgical specialties, 18 were organized in North America. Eight of the networks are related to pediatric general surgery and another eight were related to pediatric transplantation. The 16 out of 19 LHN were initiated after 2001. To date, only eight of the LHNs generated reports of comparative improved outcomes.

CONCLUSION

This scoping review provides an overview of the available LHNs in pediatric surgical specialties. Over the past decade, several pediatric surgical specialties have embraced the principles of learning health systems, forming inter-institutional collaborations that utilize information technology to generate big data on patient-level clinical information, engage in quality improvement cycles, adopt evidence-based practices, and actively involve patients and stakeholders.

LEVEL OF EVIDENCE

IV.

Increasing SARS-CoV-2 seroprevalence among UK pediatric patients on dialysis and kidney transplantation between January 2020 and August 2021

BACKGROUND

Coronavirus disease 2019 (COVID-19) was officially declared a pandemic by the World Health Organisation (WHO) on 11 March 2020, as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly across the world. We investigated the seroprevalence of anti-SARS-CoV-2 antibodies in pediatric patients on dialysis or kidney transplantation in the UK.

METHODS

Excess sera samples were obtained prospectively during outpatient visits or haemodialysis sessions and analysed using a custom immunoassay calibrated with population age-matched healthy controls. Two large pediatric centres contributed samples.

RESULTS

In total, 520 sera from 145 patients (16 peritoneal dialysis, 16 haemodialysis, 113 transplantation) were analysed cross-sectionally from January 2020 until August 2021. No anti-SARS-CoV-2 antibody positive samples were detected in 2020 when lockdown and enhanced social distancing measures were enacted. Thereafter, the proportion of positive samples increased from 5% (January 2021) to 32% (August 2021) following the emergence of the Alpha variant. Taking all patients, 32/145 (22%) were seropositive, including 8/32 (25%) with prior laboratory-confirmed SARS-CoV-2 infection and 12/32 (38%) post-vaccination (one of whom was also infected after vaccination). The remaining 13 (41%) seropositive patients had no known stimulus, representing subclinical cases. Antibody binding signals were comparable across patient ages and dialysis versus transplantation and highest against full-length spike protein versus spike subunit-1 and nucleocapsid protein.

CONCLUSIONS

Anti-SARS-CoV-2 seroprevalence was low in 2020 and increased in early 2021. Serological surveillance complements nucleic acid detection and antigen testing to build a greater picture of the epidemiology of COVID-19 and is therefore important to guide public health responses. A higher resolution version of the Graphical abstract is available as Supplementary information.

Kidney involvement in children during the SARS-CoV-2 Omicron variant pandemic

BACKGROUND

As the coronavirus disease-2019 (COVID-19) pandemic continues, driven by the Omicron variant, infection rates in children have recently rapidly surged compared with previous years. We aimed to investigate the presentation of kidney involvement in children after Omicron variant severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection.

METHODS

We retrospectively reviewed the medical records of pediatric patients who presented with kidney disease with a temporal relationship with COVID-19 between January and August 2022 in a single tertiary center in Korea.

RESULTS

Fifteen children presented with kidney involvement after Omicron variant infection, with a median age of 10.6 (6.8-18.3) years. None of the patients exhibited severe respiratory symptoms apart from cough and sore throat. The median time from infection to renal symptom onset was 3 (0-49) days. Among 10 patients with underlying kidney disease, six had previously been diagnosed with nephrotic syndrome (NS) that relapsed after COVID-19 infection, two with immunoglobulin A nephropathy (IgAN) experienced transient gross hematuria (GHU) with or without acute kidney injury (AKI), and two with kidney transplantation presented with AKI. Of the five patients without underlying kidney disease, one patient had NS, and the other four patients had GHU and proteinuria (PU), of whom one was eventually diagnosed with Henoch Shönlein Purpura nephritis (HSPN), and one with rhabdomyolysis. The seven patients with NS (1 new-onset, 6 relapsed) had uneventful remission with corticosteroid therapy. Apart from one patient with new-onset HSPN, GHU and PU resolved spontaneously in all affected patients, and AKI also resolved with supportive care.

CONCLUSIONS

Kidney involvement subsequent to Omicron variant COVID-19 exhibited various, but mostly mild manifestations in children.

COVID-19 Disease in Pediatric Solid Organ Transplantation from Alpha to Omicron: A High Monocyte Count in the Preceding Three Months Portends a Risk for Severe Disease

IMPORTANCE

Planning for future resurgences in SARS-CoV-2 infection is necessary for providers who care for immunocompromised patients.

OBJECTIVE

to determine factors associated with COVID-19 disease severity in immunosuppressed children.

DESIGN

a case series of children with solid organ transplants diagnosed with SARS-CoV-2 infection between 15 March 2020 and 31 March 2023.

SETTING

a single pediatric transplant center.

PARTICIPANTS

all children with a composite transplant (liver, pancreas, intestine), isolated intestine transplant (IT), isolated liver transplant LT), or simultaneous liver kidney transplant (SLK) with a positive PCR for SARS-CoV-2.

EXPOSURE

SARS-CoV-2 infection.

MAIN OUTCOME AND MEASURES

We hypothesized that children on the most immunosuppression, defined by the number of immunosuppressive medications and usage of steroids, would have the most severe disease course and that differential white blood cell count in the months preceding infection would be associated with likelihood of having severe disease. The hypothesis being tested was formulated during data collection. The primary study outcome measurement was disease severity defined using WHO criteria.

RESULTS

77 children (50 LT, 24 intestine, 3 SLK) were infected with SARS-CoV-2, 57.4 months from transplant (IQR 19.7-87.2). 17% were ≤1 year post transplant at infection. 55% were male, 58% were symptomatic and ~29% had severe disease. A high absolute lymphocyte count at diagnosis decreased the odds of having severe COVID-19 disease (OR 0.29; CI 0.11-0.60; p = 0.004). Conversely, patients with a high absolute monocyte count in the three months preceding infection had increased odds of having severe disease (OR 30.49; CI 1.68-1027.77; p = 0.033). Steroid use, higher tacrolimus level, and number of immunosuppressive medications at infection did not increase the odds of having severe disease.

CONCLUSIONS AND RELEVANCE

The significance of a high monocyte count as predictor of severe disease potentially confirms the importance of monocytic inflammasome-driven inflammation in COVID-19 pathogenesis. Our data do not support reducing immunosuppression in the setting of infection. Our observations may have important ramifications in resource management as vaccine- and infection-induced immunity wanes.

Reduced Humoral and Cellular Immune Response to Primary COVID-19 mRNA Vaccination in Kidney Transplanted Children Aged 5-11 Years

The situation of limited data concerning the response to COVID-19 mRNA vaccinations in immunocom-promised children hinders evidence-based recommendations. This prospective observational study investigated humoral and T cell responses after primary BNT162b2 vaccination in secondary immunocompromised and healthy children aged 5-11 years. Participants were categorized as: children after kidney transplantation (KTx, n = 9), proteinuric glomerulonephritis (GN, n = 4) and healthy children (controls, n = 8). Expression of activation-induced markers and cytokine secretion were determined to quantify the T cell response from PBMCs stimulated with peptide pools covering the spike glycoprotein of SARS-CoV-2 Wuhan Hu-1 and Omicron BA.5. Antibodies against SARS-CoV-2 spike receptor-binding domain were quantified in serum. Seroconversion was detected in 56% of KTx patients and in 100% of the GN patients and controls. Titer levels were significantly higher in GN patients and controls than in KTx patients. In Ktx patients, the humoral response increased after a third immunization. No differences in the frequency of antigen-specific CD4+ and CD8+ T cells between all groups were observed. T cells showed a predominant anti-viral capacity in their secreted cytokines; however, this capacity was reduced in KTx patients. This study provides missing evidence concerning the humoral and T cell response in immunocompromised children after COVID-19 vaccination.

Donor specific antibody surveillance among pediatric kidney transplant programs: A report from the improving renal outcome collaborative

BACKGROUND

Kidney transplantation (KT) is the preferred treatment for children with end-stage kidney disease. Recent advances in immunosuppression and advances in donor specific antibody (DSA) testing have resulted in prolonged allograft survival; however, standardized approaches for surveillance DSA monitoring and management of de novo (dn) DSA are widely variable among pediatric KT programs.

METHODS

Pediatric transplant nephrologists in the multi-center Improving Renal Outcomes Collaborative (IROC) participated in a voluntary, web-based survey between 2019 and 2020. Centers provided information pertaining to frequency and timing of routine DSA surveillance and theoretical management of dnDSA development in the setting of stable graft function.

RESULTS

29/30 IROC centers responded to the survey. Among the participating centers, screening for DSA occurs, on average, every 3 months for the first 12 months post-transplant. Antibody mean fluorescent intensity and trend most frequently directed changes in patient management. Increased creatinine above baseline was reported by all centers as an indication for DSA assessment outside of routine surveillance testing. 24/29 centers would continue to monitor DSA and/or intensify immunosuppression after detection of antibodies in the setting of stable graft function. In addition to enhanced monitoring, 10/29 centers reported performing an allograft biopsy upon detection of dnDSA, even in the setting of stable graft function.

CONCLUSIONS

This descriptive report is the largest reported survey of pediatric transplant nephrologist practice patterns on this topic and provides a reference for monitoring dnDSA in the pediatric kidney transplant population.

COVID-19 in pediatric kidney transplantation: a follow-up report of the Improving Renal Outcomes Collaborative

BACKGROUND

We report follow-up data from an ongoing prospective cohort study of COVID-19 in pediatric kidney transplantation through the Improving Renal Outcomes Collaborative (IROC).

METHODS

Patient-level data from the IROC registry were combined with testing, indication, and outcomes data collected to describe the epidemiology of COVID testing, treatment, and clinical outcomes; determine the incidence of a positive COVID-19 test; describe rates of COVID-19 testing; and assess for clinical predictors of a positive COVID-19 test.

RESULTS

From September 2020 to February 2021, 21 centers that care for 2690 patients submitted data from 648 COVID-19 tests on 465 patients. Most patients required supportive care only and were treated as outpatients, 16% experienced inpatient care, and 5% experienced intensive care. Allograft complications were rare, with acute kidney injury most common (7%). There was 1 case of respiratory failure and 1 death attributed to COVID-19. Twelve centers that care for 1730 patients submitted complete testing data on 351 patients. The incidence of COVID-19 among patients at these centers was 4%, whereas the incidence among tested patients was 19%. Risk factors to predict a positive COVID-19 test included age > 12 years, symptoms consistent with COVID-19, and close contact with a confirmed case of COVID-19.

CONCLUSIONS

Despite the increase in testing and positive tests over this study period, the incidence of allograft loss or death related to COVID-19 remained extremely low, with allograft loss or death each occurring in < 1% of COVID-19-positive patients and in less than < 0.1% of all transplant patients within the IROC cohort. A higher resolution version of the Graphical abstract is available as Supplementary information.

The learning health system for pediatric nephrology: building better systems to improve health

Learning health systems (LHS) align science, informatics, incentives, and culture for continuous improvement and innovation. In this organizational system, best practices are seamlessly embedded in the delivery process, and new knowledge is captured as an integral byproduct of the care delivery experience aimed to transform clinical practice and improve patient outcomes. The objective of this review is to describe how building better health systems that integrate clinical care, improvement, and research as part of an LHS can improve care within pediatric nephrology. This review will provide real-world examples of how this system can be established in a single center and across multiple centers as learning health networks.

COVID-19 in pediatric lung transplant recipients: Clinical course and outcome

BACKGROUND

COVID-19 causes high morbidity and mortality in adult lung transplant (LTX) recipients. Data on COVID-19 in children after LTX is limited. We report the clinical presentation and outcome of SARS-CoV-2 infection in 19 pediatric LTX recipients.

METHODS

Between March 2020 and June 2022, SARS-CoV-2 testing was performed on all pediatric LTX patients with COVID-19 symptoms or contact with a SARS-CoV-2 infected person. Positive patients were prospectively evaluated for symptoms, treatment and outcome. Vaccination status and immune response were recorded.

RESULTS

Nineteen out of 51 pediatric LTX recipients had a SARS-CoV-2 infection. Mean age was 12.3 years (IQR 9-17), 68% were female, 84% had preexisting comorbidities. Mean time between LTX and SARS-CoV-2 infection was 4.8 years (IQR 2-6). No patients experienced severe COVID-19: 11% were asymptomatic, and 89% had mild symptoms, primarily rhinitis (74%), fever (47%), and cough (37%). One SARS-CoV-2 positive patient was hospitalized due to combined fungal and bacterial infection. Mean duration of symptoms was 10.5 days (IQR 3-16), whereas mean period of positivity by antigen test was 21 days (IQR 9-27, p = 0.013). Preventive antiviral therapy was initiated in 3 patients. After a mean follow-up of 2.5 months (IQR 1.1-2.4), no patient reported persistent complaints related to COVID-19. Lung function tests remained stable.

CONCLUSIONS

Unlike adult LTX recipients, children and adolescents are at low risk for severe COVID-19, even with risk factors beyond immunosuppression. Our findings cast doubt on the necessity of excessive isolation for these patients and should reassure clinicians and caregivers of LTX patients.

Impact of the COVID-19 pandemic on the kidney community: lessons learned and future directions

The coronavirus disease 2019 (COVID-19) pandemic has disproportionately affected patients with kidney disease, causing significant challenges in disease management, kidney research and trainee education. For patients, increased infection risk and disease severity, often complicated by acute kidney injury, have contributed to high mortality. Clinicians were faced with high clinical demands, resource shortages and novel ethical dilemmas in providing patient care. In this review, we address the impact of COVID-19 on the entire spectrum of kidney care, including acute kidney injury, chronic kidney disease, dialysis and transplantation, trainee education, disparities in health care, changes in health care policies, moral distress and the patient perspective. Based on current evidence, we provide a framework for the management and support of patients with kidney disease, infection mitigation strategies, resource allocation and support systems for the nephrology workforce.

The impact of COVID-19 on the pediatric solid organ transplant population

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has significantly impacted all aspects of healthcare including solid organ transplantation. In this review, we discuss the specific impact of COVID-19 on the pediatric solid organ transplant population including access to grafts for pediatric transplant candidates as well as COVID-19 disease manifestations in pediatric transplant recipients. We address the current knowledge of prevention and management of COVID-19 in pediatric transplant recipients and provide additional information regarding social distancing, infection prevention and return to school.

Updated Guidance on Use and Prioritization of Monoclonal Antibody Therapy for Treatment of COVID-19 in Adolescents

BACKGROUND

Starting in November 2020, the US Food and Drug Administration (FDA) has issued Emergency Use Authorizations (EUAs) for multiple novel virus-neutralizing monoclonal antibody therapies, including bamlanivimab monotherapy (now revoked), bamlanivimab and etesivimab, casirivimab and imdevimab (REGEN-COV), and sotrovimab, for treatment or postexposure prophylaxis of Coronavirus disease 2019 (COVID-19) in adolescents (≥12 years of age) and adults with certain high-risk conditions. Previous guidance is now updated based on new evidence and clinical experience.

METHODS

A panel of experts in pediatric infectious diseases, pediatric infectious diseases pharmacotherapy, and pediatric critical care medicine from 18 geographically diverse US institutions was convened. Through a series of teleconferences and web-based surveys, a guidance statement was developed and refined based on a review of the best available evidence and expert opinion.

RESULTS

The course of COVID-19 in children and adolescents is typically mild, though more severe disease is occasionally observed. Evidence supporting risk stratification is incomplete. Randomized controlled trials have demonstrated the benefit of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-specific monoclonal antibody therapies in adults, but data on safety and efficacy in children or adolescents are limited. Potential harms associated with infusion reactions or anaphylaxis are reportedly low in adults.

CONCLUSIONS

Based on evidence available as of August 31, 2021, the panel suggests a risk-based approach to administration of SARS-CoV-2 monoclonal antibody therapy. Therapy is suggested for the treatment of mild to moderate COVID-19 in adolescents (≥12 years of age) at the highest risk of progression to hospitalization or severe disease. Therapeutic decision-making about those at moderate risk of severe disease should be individualized. Use as postexposure prophylaxis could be considered for those at the highest risk who have a high-risk exposure but are not yet diagnosed with COVID-19. Clinicians and health systems should ensure safe and timely implementation of these therapeutics that does not exacerbate existing healthcare disparities.

Pediatric transplantation during the COVID-19 pandemic

Children infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seem to have a better prognosis than adults. Nevertheless, pediatric solid organ transplantation (SOT) has been significantly affected by the unprecedented coronavirus disease 2019 (COVID-19) pandemic during the pre-, peri-, and post-transplant period. Undoubtedly, immunosuppression constitutes a real challenge for transplant clinicians as increased immunosuppression may prolong disease recovery, while its decrease can contribute to more severe symptoms. To date, most pediatric SOT recipients infected by SARS-CoV-2 experience mild disease with only scarce reports of life-threatening complications. As a consequence, after an initial drop during the early phase of the pandemic, pediatric SOTs are now performed with the same frequency as during the pre-pandemic period. This review summarizes the currently available evidence regarding pediatric SOT during the COVID-19 pandemic.

Occurrence and transmission potential of asymptomatic and presymptomatic SARS-CoV-2 infections: Update of a living systematic review and meta-analysis

BACKGROUND

Debate about the level of asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection continues. The amount of evidence is increasing and study designs have changed over time. We updated a living systematic review to address 3 questions: (1) Among people who become infected with SARS-CoV-2, what proportion does not experience symptoms at all during their infection? (2) What is the infectiousness of asymptomatic and presymptomatic, compared with symptomatic, SARS-CoV-2 infection? (3) What proportion of SARS-CoV-2 transmission in a population is accounted for by people who are asymptomatic or presymptomatic?

METHODS AND FINDINGS

The protocol was first published on 1 April 2020 and last updated on 18 June 2021. We searched PubMed, Embase, bioRxiv, and medRxiv, aggregated in a database of SARS-CoV-2 literature, most recently on 6 July 2021. Studies of people with PCR-diagnosed SARS-CoV-2, which documented symptom status at the beginning and end of follow-up, or mathematical modelling studies were included. Studies restricted to people already diagnosed, of single individuals or families, or without sufficient follow-up were excluded. One reviewer extracted data and a second verified the extraction, with disagreement resolved by discussion or a third reviewer. Risk of bias in empirical studies was assessed with a bespoke checklist and modelling studies with a published checklist. All data syntheses were done using random effects models. Review question (1): We included 130 studies. Heterogeneity was high so we did not estimate a mean proportion of asymptomatic infections overall (interquartile range (IQR) 14% to 50%, prediction interval 2% to 90%), or in 84 studies based on screening of defined populations (IQR 20% to 65%, prediction interval 4% to 94%). In 46 studies based on contact or outbreak investigations, the summary proportion asymptomatic was 19% (95% confidence interval (CI) 15% to 25%, prediction interval 2% to 70%). (2) The secondary attack rate in contacts of people with asymptomatic infection compared with symptomatic infection was 0.32 (95% CI 0.16 to 0.64, prediction interval 0.11 to 0.95, 8 studies). (3) In 13 modelling studies fit to data, the proportion of all SARS-CoV-2 transmission from presymptomatic individuals was higher than from asymptomatic individuals. Limitations of the evidence include high heterogeneity and high risks of selection and information bias in studies that were not designed to measure persistently asymptomatic infection, and limited information about variants of concern or in people who have been vaccinated.

CONCLUSIONS

Based on studies published up to July 2021, most SARS-CoV-2 infections were not persistently asymptomatic, and asymptomatic infections were less infectious than symptomatic infections. Summary estimates from meta-analysis may be misleading when variability between studies is extreme and prediction intervals should be presented. Future studies should determine the asymptomatic proportion of SARS-CoV-2 infections caused by variants of concern and in people with immunity following vaccination or previous infection. Without prospective longitudinal studies with methods that minimise selection and measurement biases, further updates with the study types included in this living systematic review are unlikely to be able to provide a reliable summary estimate of the proportion of asymptomatic infections caused by SARS-CoV-2.

REVIEW PROTOCOL

Open Science Framework (https://osf.io/9ewys/).

COVID-19 Infections in Pediatric Renal Transplant Recipients

OBJECTIVES

The new coronavirus SARS-CoV-2 (COVID-19) first appeared in Turkey in March 2020, spread rapidly, and caused many deaths. Although COVID-19 is mostly a respiratory disease, it can cause kidney and multiorgan failure in some cases. We believe that by sharing information about the course and effects of COVID-19 infection in kidney transplant recipients receiving long-term immunosuppressive therapy our understanding will improve.

MATERIALS AND METHODS

Between March 2020 and October 2021, COVID-19 was researched in kidney transplant recipients under the age of 20 years who were followed at the Başkent University Transplantation Center. We documented the clinical characteristics and prognosis of pediatric kidney transplant recipients with COVID-19 disease.

RESULTS

Our study group included 23 patients with COVID-19 infection from 215 pediatric kidney transplant recipients. The mean age of the patients was 14.6 ± 4.7 years; there were 9 female patients. The mean follow-up time posttransplant was 62.3 ± 43.2 months. In 13 patients (56.5%), fever was the most frequent symptom. Most patients (n = 18, 78%) had minor symptoms and recovered completely after receiving supportive treatment. Four patients (17%) required hospitalization. One was diagnosed with COVID-19 infection 1 week after being treated with rituximab for acute antibody-mediated rejection. That patient died because of significant lung disease and multiorgan failure.

CONCLUSIONS

Despite the fact that most of our pediatric transplant recipients had mild symptoms of COVID-19, we believe that particular caution should be observed in patients who have recently received intensive immunosuppressive medications. As a result of potential new vaccines, national immunization programs, and the emergence of novel virus strains, the clinical picture may change in the future. We believe that, as information sharing increases, we will learn more about COVID-19 in renal transplant recipients.

COVID-19 infection in pediatric solid organ transplant patients

BACKGROUND

Adult SOT recipients with COVID-19 have higher mortality rates when compared to general population. There is paucity of data on outcomes in pediatric SOT recipients.

METHODS

This is a cross-sectional study investigating the prevalence of COVID-19 infection and outcomes in pediatric SOT (heart, liver, and kidney) recipients. We extracted demographic and clinical characteristics and COVID-19 testing (PCR or [Ab] test) results from medical records. Clinical characteristics were compared between patients who were positive for COVID-19 (PCR or Ab) and those who did not, using Mann-Whitney, Student's t test, or chi-square test. p value <.05 was statistically significant.

RESULTS

A total of 108 SOT recipients with a median age of 13.1 (8.4, 17.8) years and median 4.2 (2.7, 7.9) years from transplant were checked for COVID-19 via a PCR or Ab test. A positive PCR was confirmed in 10 patients (9.3%), while 12 patients (11.1%) were positive for COVID-19 Ab. The patients who tested positive in our cohort were 9/50 (18%) heart, 6/68 (8.8%) kidney, and 7/50 (14%) liver transplant recipients. There were no differences in the clinical characteristics between patients with and without COVID-19 infection. All patients were either asymptomatic (50%) or had self-limiting symptoms. No changes were made to the immunosuppressive regimen. Only one patient was hospitalized and none had an oxygen requirement.

CONCLUSIONS

In our cohort of pediatric SOT recipients, COVID-19 infection was asymptomatic or mild. This data may aid clinicians in counseling patients and families in this increased-risk population.

Return to School and COVID-19 Vaccination for Pediatric Solid Organ Transplant Recipients in the United States: Expert Opinion for 2021-2022

The COVID-19 pandemic continues to generate challenges for pediatric solid organ transplant (SOT) recipients and their families. As rates of COVID-19 fluctuate, new SARS-CoV-2 variants emerge, and adherence to and implementation of mitigation strategies vary from community to community, questions remain about the best and safest practices to prevent COVID-19 in vulnerable patients. Notably, decisions about returning to school remain difficult. We assembled a team of specialists in pediatric infectious diseases, transplant infectious diseases, public health, transplant psychology, and infection prevention and control to re-address concerns about school re-entry, as well as COVID-19 vaccines, for pediatric SOT recipients in the United States in 2021. Based on available literature and guidance from national organizations, we generated expert statements specific to pediatric SOT recipients focused on school attendance in 2021.

The case against COVID-19 vaccine mandates in pediatric solid organ transplantation

BACKGROUND

The American Society of Transplantation in conjunction with the International Society for Heart and Lung Transplantation released a joint statement on August 13, 2021 in which they strongly recommend that solid organ transplant (SOT) recipients and their eligible household members and close contacts be vaccinated against SARS-CoV-2 with an approved COVID-19 vaccine. Some SOT programs have gone further and will refuse to list or transplant candidates unless the candidate and their household are vaccinated against SARS-CoV-2.

METHODS

Two general pediatrician-ethicists use current best evidence and moral theory to argue why it is unethical to mandate COVID-19 vaccination for pediatric SOT candidates, their primary support person, and their households.

RESULTS

Pediatric vaccine mandates are most justifiable when they prevent the harm of a serious vaccine preventable disease (VPD) in children in settings where transmission is highly likely and there are no alternatives that are effective in preventing transmission that intrude less on individual freedom. An additional justification for a vaccine mandate in the SOT context is stewardship of a scarce resource if there is significant risk of graft loss from the VPD to an unvaccinated SOT candidate or recipient. Current evidence does not support fulfillment of these criteria in pediatric solid organ transplantation.

CONCLUSIONS

Making SOT listing contingent on COVID-19 vaccination is problematic. Though there is some risk of harm to a pediatric SOT candidate in remaining unvaccinated, the risk of harm of not being listed and transplanted is greater and overriding.

COVID-19 in pediatric patients undergoing chronic dialysis and kidney transplantation

The study aims to present the incidence of COVID-19 in pediatric patients undergoing renal replacement therapy (RRT) and to compare the severity and outcomes of the disease between the dialysis and kidney transplant (KTx) groups. This multicenter observational study was conducted between 1 April and 31 December 2020 in Istanbul. Members of the Istanbul branch of the Turkish Pediatric Nephrology Association were asked to report all confirmed cases of COVID-19 who were on RRT, as well as the number of prevalent RRT patients under the age of 20. A total of 46 confirmed cases of COVID-19 were reported from 12 centers, of which 17 were dialysis patients, and 29 were KTx recipients. Thus, the incidence rate of COVID-19 was 9.3% among dialysis patients and 9.2% among KTx recipients over a 9-month period in Istanbul. Twelve KTx recipients and three dialysis patients were asymptomatic (p = 0.12). Most of the symptomatic patients in both the dialysis and KTx groups had a mild respiratory illness. Only two patients, one in each group, experienced a severe disease course, and only one hemodialysis patient had a critical illness that required mechanical ventilation. In the entire cohort, one hemodialysis patient with multiple comorbidities died.Conclusion: While most cases are asymptomatic or have a mild disease course, pediatric patients undergoing dialysis and a kidney transplant are at increased risk for COVID-19. What is Known: • In adult population, both dialysis patients and kidney transplant recipients are at increased risk for severe illness of COVID-19 and have higher mortality rate. • Children with kidney transplantation are not at increased risk for COVID-19 and most have mild disease course. • Data on children on dialysis are scarce. What is New: • Pediatric patients undergoing dialysis and kidney transplantation have an increased risk for COVID-19. • Most patients undergoing renal replacement therapy either on dialysis or transplanted develop asymptomatic or mild COVID-19 disease with a favorable outcome.

Considering a COVID-19 vaccine mandate for pediatric kidney transplant candidates

The world continues to face the effects of the SARS-CoV-2 pandemic. COVID-19 vaccines are safe and effective in protecting recipients, decreasing the risk of COVID-19 acquisition, transmission, hospitalization, and death. Transplant recipients may be at greater risk for severe SARS-CoV-2 infection. As a result, transplant programs have begun instituting mandates for COVID-19 vaccine for transplant candidacy. While the question of mandating COVID-19 vaccine for adult transplant candidates has garnered attention in the lay and academic press, these discussions have not explicitly addressed children who may be otherwise eligible for kidney transplants. In this paper we seek to examine the potential ethical justifications of a COVID-19 vaccine mandate for pediatric kidney transplant candidacy through an examination of relevant ethical principles, analogous cases of the use of mandates, differences between adult and pediatric kidney transplant candidates, and the role of gatekeeping in transplant vaccine mandates. At present, it does not appear that pediatric kidney transplant centers are justified to institute a COVID-19 vaccine mandate for candidates. Finally, we will offer suggestions to be considered prior to the implementation of a COVID-19 vaccine mandate.

Kidney implications of SARS-CoV2 infection in children

Research indicates that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection can impact every organ, and the effects can range from asymptomatic to severe disease. Since it was first discovered in December 2019, our understanding has grown about its impact on kidney disease. In general, children have less severe disease than adults, and this tendency appears to extend to special pediatric kidney populations (e.g., chronic kidney disease and immunosuppressed patients with solid organ transplants or nephrotic syndrome). However, in a fraction of infected children, SARS-CoV2 causes an array of kidney manifestations, ranging from acute kidney injury to thrombotic microangiopathy, with potential implications for increased risk of morbidity and mortality. Additional considerations surround the propensity for clotting extracorporeal circuits in children with SARS-CoV2 infection that are receiving kidney replacement therapy. This review provides an update on our current understanding of SARS-CoV2 for pediatric nephrologists and highlights knowledge gaps to be addressed by future research during this ongoing pandemic, particularly the social disparities magnified during this period.

Global Percentage of Asymptomatic SARS-CoV-2 Infections Among the Tested Population and Individuals With Confirmed COVID-19 Diagnosis: A Systematic Review and Meta-analysis

IMPORTANCE

Asymptomatic infections are potential sources of transmission for COVID-19.

OBJECTIVE

To evaluate the percentage of asymptomatic infections among individuals undergoing testing (tested population) and those with confirmed COVID-19 (confirmed population).

DATA SOURCES

PubMed, EMBASE, and ScienceDirect were searched on February 4, 2021.

STUDY SELECTION

Cross-sectional studies, cohort studies, case series studies, and case series on transmission reporting the number of asymptomatic infections among the tested and confirmed COVID-19 populations that were published in Chinese or English were included.

DATA EXTRACTION AND SYNTHESIS

This meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Random-effects models were used to estimate the pooled percentage and its 95% CI. Three researchers performed the data extraction independently.

MAIN OUTCOMES AND MEASURES

The percentage of asymptomatic infections among the tested and confirmed populations.

RESULTS

Ninety-five unique eligible studies were included, covering 29 776 306 individuals undergoing testing. The pooled percentage of asymptomatic infections among the tested population was 0.25% (95% CI, 0.23%-0.27%), which was higher in nursing home residents or staff (4.52% [95% CI, 4.15%-4.89%]), air or cruise travelers (2.02% [95% CI, 1.66%-2.38%]), and pregnant women (2.34% [95% CI, 1.89%-2.78%]). The pooled percentage of asymptomatic infections among the confirmed population was 40.50% (95% CI, 33.50%-47.50%), which was higher in pregnant women (54.11% [95% CI, 39.16%-69.05%]), air or cruise travelers (52.91% [95% CI, 36.08%-69.73%]), and nursing home residents or staff (47.53% [95% CI, 36.36%-58.70%]).

CONCLUSIONS AND RELEVANCE

In this meta-analysis of the percentage of asymptomatic SARS-CoV-2 infections among populations tested for and with confirmed COVID-19, the pooled percentage of asymptomatic infections was 0.25% among the tested population and 40.50% among the confirmed population. The high percentage of asymptomatic infections highlights the potential transmission risk of asymptomatic infections in communities.

Serological Response to the BNT162b2 COVID-19 mRNA Vaccine in Adolescent and Young Adult Kidney Transplant Recipients

BACKGROUND

Initial reports in adult kidney transplant recipients (KTR) indicate low immunogenicity after 2 doses of the BNT162b2 COVID-19 mRNA vaccine. We describe the immunogenicity of this vaccine compared to the serologic response in naturally infected COVID-19 positive adolescent and young adult KTR.

METHODS

For this prospective observational study, the study group included 38 KTR who received 2 doses of the tested vaccine, and the control group included 14 KTR who had a previous polymerase chain reaction-confirmed COVID-19 infection.

RESULTS

The mean age was 18 ± 3 y. Positive serologic responses were observed in 63% and 100% of the study and control groups, respectively (P = 0.01). Antibody titers were almost 30-fold higher in the control than the study group (median [interquartile range (IQR)]: 2782 [1908-11 000] versus 100.3 [4.7-1744] AU/mL, P < 0.001), despite the longer time from the COVID-19 infection to serologic testing compared to time from vaccination (median [IQR]: 157.5 [60-216] versus 37 [20.5-53] d, P = 0.011). Among vaccinated patients, higher proportions of those seronegative than seropositive were previously treated with rituximab (50% versus 8%, P = 0.01). Time from the second vaccine dose to serologic testing was longer in seropositive than seronegative patients (median [IQR]: 24.5 [15-40] versus 46 [27-56] d, P = 0.05). No patient developed symptomatic COVID-19 disease postvaccination.

CONCLUSIONS

The BNT162b2 COVID-19 mRNA vaccine yielded higher positive antibody response in adolescent and young adult KTR than previously reported for adult KTR. Antibody titers after vaccination were significantly lower than following COVID-19 infection. Longer time may be required to mount appropriate humoral immunity to vaccination in KTR.

COVID-19 in children and young adults with kidney disease: risk factors, clinical features and serological response

BACKGROUND

Chronic kidney disease (CKD) and kidney transplantation in adults are well-recognized risk factors for coronavirus disease 2019 (COVID-19) associated morbidity and mortality. Data on the toll of the pandemic on children and young adults with kidney disease is scarce. The aim of this study was to assess the incidence and severity of COVID-19, as well as the serological response, in this population.

METHODS

Study population included all patients with CKD stage 3-5, glomerular disease treated with immunosuppression and kidney transplant recipients followed-up at a tertiary medical center, between 1.12.2020 and 15.2.2021. Data collected included PCR testing, symptoms, exposure, and socio-demographic data. Anti-SARS-CoV-2 antibodies were tested.

RESULTS

A total of 197 children and 63 young adults were included, 57% were Jewish, 43% were Arab. PCR-confirmed COVID-19 incidence was 20.8%, 37% of cases were asymptomatic, three patients were hospitalized for observation, and the remainder had mild symptoms. Kidney function remained stable without treatment modification. Risk factors for infection included exposure at home (OR 15.4, 95% CI 6.9-34.2) and number of household members (OR 1.45, 95% CI 1.21-1.73). Anti-SARS-CoV-2 antibodies were detected in 61% of cases and were not associated with COVID-19 severity or immunosuppressive therapy. Three patients who did not develop antibodies had a mild recurrent infection.

CONCLUSIONS

Unlike COVID-19 in adult patients with kidney disease, in our cohort of children and young adults, COVID-19 incidence was similar to the general population and all cases were mild. It may be unnecessary to impose severe restrictions on this patient population during the pandemic.

De novo collapsing glomerulopathy in a pediatric kidney transplant recipient with COVID-19 infection

The negative impact of COVID-19 on adults with underlying chronic kidney disease, including kidney transplant recipients, has been well documented. Children have a less severe presentation and better prognosis compared to adults. However, little is known regarding the spectrum of COVID-19 infection in children and adolescents with underlying autoimmune disorders necessitating solid organ transplant and long-term immunosuppressive therapy. Case Report. An adolescent male developed end-stage kidney disease secondary to microscopic polyangiitis requiring a living-donor kidney transplant. Six years later, he developed antibody-mediated rejection of his kidney transplant. During his rejection treatment course, he contracted SARS-CoV-2 and developed new-onset nephrotic syndrome with severe acute kidney injury. Kidney transplant biopsy revealed de novo collapsing focal segmental glomerulosclerosis on a background of chronic active antibody mediated rejection. Immunostaining for SARS-CoV-2 on the biopsy specimen demonstrated positive staining of the proximal tubular epithelium consistent with intra-renal viral infection. Pulse corticosteroids, intravenous immunoglobulin, and temporary reduction of anti-metabolite therapy resulted in successful recovery with return of graft function back to pre-infection baseline. This case highlights the clinical conundrum of treating kidney transplant recipients with active rejection in the midst of the COVID-19 pandemic. Pediatric kidney transplant recipients can develop severe COVID-19-related kidney complications. Judicious immunosuppression modulation is necessary to balance infection and rejection risk.