Epstein-Barr virus DNA monitoring in serum and whole blood in pediatric liver transplant recipients who do or do not discontinue immunosuppressive therapy

The IPTA Nashville consensus conference on post-transplant lymphoproliferative disorders after solid organ transplantation in children: IV-consensus guidelines for the management of post-transplant lymphoproliferative disorders in children and adolescents

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders (PTLD) after pediatric solid organ transplantation. This report addresses the outcomes of deliberations by the PTLD Management Working Group. A strong recommendation was made for reduction in immunosuppression as the first step in management. Similarly, strong recommendations were made for the use of the anti-CD20 monoclonal antibody (rituximab) as was the case for chemotherapy in selected scenarios. In some scenarios, there is uncoupling of the strength of the recommendations from the available evidence in situations where such evidence is lacking but collective clinical experiences drive decision-making. Of note, there are no large, randomized phase III trials of any treatment for PTLD in the pediatric age group. Current gaps and future research priorities are highlighted.

Nutrition and Epstein-Barr viremia in children underwent liver transplantation: A retrospective, cross-sectional study

BACKGROUND AND AIMS

We aimed to examine the association between nutritional status, assessed by height/length and body weight for age and sex, and Epstein-Barr virus (EBV) viremia in children underwent liver transplantation.

METHODS

Nutritional status was determined by total score of age- and sex-specific height/length and body weight: < (-2 SD) as "2 points", (-2 SD to -1 SD) as "1 point", and ≥ (-1SD) as "0 point". Children were further classified into three groups: malnutrition (4 points), risk of malnutrition (1-3 points), and normal (0 point). EBV viremia were confirmed by real time quantitative PCR method if EBV burden was ≥400 copies/ml.

RESULTS

A total number of 896 children (414 boys and 482 girls, medium age 8 months) were included in the study. The medium height was 65.0 cm while medium body weight was 7.0 kg. The prevalence of EBV viremia was 54.6% during follow up. Comparing with children with normal nutritional status, the adjusted odds ratios for the risk of EBV viremia was 2.14 (95% CI: 1.44, 3.19) in children with risk of malnutrition, and 2.29 (95% CI: 1.54, 3.40) in children with malnutrition. Each point increase of nutritional score was associated with a 21% higher risk of EBV viremia (odd ratios = 1.21; 95% CI: 1.10, 1.34) in fully adjusted model.

CONCLUSIONS

Nutritional score was associated with EBV viremia in children underwent liver transplantation.

Epidemiology of Epstein-Barr Virus Chronic High Viral Load in Kidney Transplant Recipients

Background

Epstein-Barr virus (EBV) chronic high viral load (CHVL) may be defined by >16 000 copies/mL whole blood or >200 copies/105 peripheral blood mononuclear cells in >50% samples exceeding 6 mo. EBV CHVL has only been characterized in a few small pediatric studies, with heterogeneous results and unclear clinical significance.

Methods

This single-center observational study evaluated adult and pediatric kidney transplant recipients transplanted between 2010 and 2021 on tacrolimus/mycophenolate-based/prednisone immunosuppression. The primary outcome was EBV CHVL prevalence. Secondary outcomes included recipient characteristics, DNAemia kinetics, and posttransplant lymphoproliferative disorder (PTLD) in recipients with EBV CHVL versus low-grade DNAemia or no DNAemia.

Results

Five hundred forty-one recipients had a mean follow-up of 4.6 y. Fourteen recipients (2.6%) developed EBV CHVL, 70 (12.9%) had low-grade EBV DNAemia, and 457 (84.5%) had no EBV DNAemia. EBV CHVL was more common in recipients who were Caucasian (P = 0.04), younger (P = 0.04), received induction immunosuppression (P = 0.02), and had high-risk donor-recipient EBV serologic mismatch (P < 0.0001). CHVL patients had a higher first viral load (P = 0.03), longer time to maximum viral load (P = 0.02), and did not achieve sustained DNAemia clearance versus low-grade DNAemia. Three EBV-positive PTLD cases occurred in recipients with a history of EBV DNAemia. PTLD was present in 7.1% (1/14) CHVL versus 2.9% (2/70) low-grade DNAemia patients (P = 0.002). EBV DNAemia developed in 32 EBV seronegative recipients (32/59; 54%); clearance was achieved in 70% (14/20) with low-grade DNAemia but no CHVL (0/12; P = 0.0001).

Conclusions

CHVL was uncommon and appeared to occur after primary EBV infection. Future studies should explore other potentially modifiable risk factors for PTLD, including optimal management of EBV DNAemia.

The IPTA Nashville Consensus Conference on Post-Transplant lymphoproliferative disorders after solid organ transplantation in children: III - Consensus guidelines for Epstein-Barr virus load and other biomarker monitoring

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders after solid organ transplantation in children. In this report from the Viral Load and Biomarker Monitoring Working Group, we reviewed the existing literature regarding the role of Epstein-Barr viral load and other biomarkers in peripheral blood for predicting the development of PTLD, for PTLD diagnosis, and for monitoring of response to treatment. Key recommendations from the group highlighted the strong recommendation for use of the term EBV DNAemia instead of "viremia" to describe EBV DNA levels in peripheral blood as well as concerns with comparison of EBV DNAemia measurement results performed at different institutions even when tests are calibrated using the WHO international standard. The working group concluded that either whole blood or plasma could be used as matrices for EBV DNA measurement; optimal specimen type may be clinical context dependent. Whole blood testing has some advantages for surveillance to inform pre-emptive interventions while plasma testing may be preferred in the setting of clinical symptoms and treatment monitoring. However, EBV DNAemia testing alone was not recommended for PTLD diagnosis. Quantitative EBV DNAemia surveillance to identify patients at risk for PTLD and to inform pre-emptive interventions in patients who are EBV seronegative pre-transplant was recommended. In contrast, with the exception of intestinal transplant recipients or those with recent primary EBV infection prior to SOT, surveillance was not recommended in pediatric SOT recipients EBV seropositive pre-transplant. Implications of viral load kinetic parameters including peak load and viral set point on pre-emptive PTLD prevention monitoring algorithms were discussed. Use of additional markers, including measurements of EBV specific cell mediated immunity was discussed but not recommended though the importance of obtaining additional data from prospective multicenter studies was highlighted as a key research priority.

The IPTA Nashville consensus conference on Post-Transplant lymphoproliferative disorders after solid organ transplantation in children: II-consensus guidelines for prevention

The International Pediatric Transplant Association (IPTA) convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorder after solid organ transplantation in children. In this report from the Prevention Working Group, we reviewed the existing literature regarding immunoprophylaxis and chemoprophylaxis, and pre-emptive strategies. While the group made a strong recommendation for pre-emptive reduction of immunosuppression at the time of EBV DNAemia (low to moderate evidence), no recommendations for use could be made for any prophylactic strategy or alternate pre-emptive strategy, largely due to insufficient or conflicting evidence. Current gaps and future research priorities are highlighted.

Chronic Epstein-Barr viral load carriage after pediatric organ transplantation

Epstein-Barr virus (EBV) infection and EBV-associated post-transplant lymphoproliferative disorder (EBV/PTLD) is one of the most devastating complications occurring in pediatric solid organ transplant (SOT) recipients. Observations of SOT recipients undergoing serial EBV monitoring to inform reduction of immune suppression to prevent EBV-/PTLD has identified patients who maintain chronic high EBV load (CHL) in their blood. The CHL carrier state has been seen more commonly in pediatric compared to adult transplant recipients. Some but not all CHL may progress to EBV/PTLD. However, little is known regarding the biology of this CHL carrier state and the optimal clinical approach to CHL has not been established. This review summarizes the current knowledge and evidence of chronic high EBV load and introduces commonly adopted approaches from experts in this field.

Immunosuppression-Free Life after Pediatric Liver Transplant: A Case-Control Study from the Society of Pediatric Liver Transplant (SPLIT) Registry

OBJECTIVE

To compare long-term outcomes of pediatric liver transplant (LT) recipients off immunosuppression (IS) with matched controls on IS using data from the Society of Pediatric Liver Transplant (SPLIT) registry.

STUDY DESIGN

This was a retrospective case-control study. SPLIT participants <18 years of age, ≥4 years after isolated LT, and off IS for ≥1 year (cases) were age- and sex-matched 1:2 to patients with the same primary diagnosis and post-LT follow-up duration (controls). Primary outcomes included retransplantation, allograft rejection, IS comorbidities, and prevalence of SPLIT-derived composite ideal outcome (c-IO) achieved at the end of the follow-up period. Differences were compared using multiple linear regression for continuous outcomes and logistic regression for dichotomous data.

RESULTS

The study cohort was composed of 33 cases (42.4% male, 60.6% biliary atresia, median age at LT of 0.7 [P25, P75, 0.5, 1.6] years, median IS withdrawal time of 9 [P25, P75, 6, 12] years after LT) and 66 age- and sex-matched controls. No cases required retransplantation. Cases and controls had similar growth parameters, laboratory values, calculated glomerular filtration rates, rates of post-transplant lymphoproliferative disease, graft rejection, and attainment of c-IO.

CONCLUSIONS

No differences in allograft rejection rates, IS complications, or c-IO prevalence were seen between SPLIT patients off IS and age- and sex-matched controls remaining on IS. Discontinuation of IS most commonly occurred in the context of rigorously designed IS withdrawal trials. The available sample size was small, affecting generalizability to the broader pediatric LT population.

Changes in the gut microbiome can predict and decrease Epstein-Barr virus infection risk in children after liver transplantation

OBJECTIVE

Primary Epstein-Barr virus (EBV) infection is observed in 60% of children during the first year after liver transplantation as usage of imm-unosuppressant. Finding predictive indicators of EBV infection is important to reduce the morbidity and mortality of EBV infection-related diseases by suggesting a dose reduction of immunosuppressant.

METHODS

We compared and analysed the gut microbiome of EBV-infected children with an asymptomatic virus-carrying status and EBV-uninfected children after liver transplantation using high-throughput sequencing.

RESULTS

Significant differences in gut microbiome composition in two groups were detected. In detail, Firmicutes and Lactobacillus were increased in EBV-infected group, while Clostridium was increased in EBV-uninfected group. Furthermore, CD4 percentage in T cells of blood showed a significant positive correlation with the content of Clostridium sp. CAG: 127 in EBV-uninfected group.

CONCLUSION

Changes in the gut microbiome could predict and decrease the EBV infection risk of children after liver transplantation.

Early Detection of Epstein-Barr Virus as a Risk Factor for Chronic High Epstein-Barr Viral Load Carriage at a Living-donor-dominant Pediatric Liver Transplantation Center

BACKGROUND

Epstein-Barr virus (EBV) infection and posttransplant lymphoproliferative disorders (PTLDs) after pediatric liver transplantation (LT) account for significant morbidity and mortality. Knowledge of EBV kinetics, epidemiology, and outcomes among pediatric living-donor LT cases is largely lacking. This study aims to provide clinical information related to EBV infection, chronic high EBV load (CHL) carriage, and PTLD at a living-donor-dominant pediatric LT center.

METHODS

A total of 5827 EBV load measurements from 394 LT recipients fulfilling inclusion criteria and their clinical data were analyzed. EBV loads >1000 copies/μg DNA (742 IU/μg DNA) were considered "high," and CHL was defined by persistence >6 mo.

RESULTS

The highlighted results were as follows: (1) 94% of recipients underwent living-donor LT; (2) 80% of EBV seronegative recipients developed first EBV infection <2 y post-LT, and their EBV loads were consistently higher than those of seropositive recipients within <3 y post-LT but did not differ thereafter; (3) 61 (15%) recipients met CHL criteria, but none developed PTLD; (4) age <5 y, cytomegalovirus seronegative donors, and early development of EBV DNAemia <6 mo post-LT were independent risk factors for CHL; (5) the incidence of rejections after 1-y post-LT was comparably low among CHL carriers whose immunosuppression was minimized.

CONCLUSIONS

Early detection of EBV following LT and CMV seronegative donors would facilitate risk stratification to prevent PTLD while titrating immunosuppression among pediatric LT recipients.

αβ and γδ T-cell responses to Epstein-Barr Virus: insights in immunocompetence, immune failure and therapeutic augmentation in transplant patients

Epstein-Barr Virus (EBV) is a human gamma herpes virus, which causes several diseases in immunocompetent (mononucleosis, chronic fatigue syndrome, gastric cancer, endemic Burkitt's lymphoma, head and neck cancer) and immunosuppressed (post-transplant lymphoproliferative disease, EBV-associated soft tissue tumors) patients. It elicits a complex humoral and cellular immune response with both innate and adaptive immune components. Substantial progress has been made in understanding the interplay of immune cells in EBV-associated diseases in recent years, and several therapeutic approaches have been developed to augment cellular immunity toward EBV for control of EBV-associated malignancy. This review will focus on recent developments in immunosuppressed transplant recipients.

Epstein-Barr Viral Load Monitoring Strategy and the Risk for Posttransplant Lymphoproliferative Disease in Adult Liver Transplantation : A Cohort Study

BACKGROUND

Primary infection with or reactivation of Epstein-Barr virus (EBV) can occur after liver transplant (LT) and can lead to posttransplant lymphoproliferative disease (PTLD). In pediatric LT, an EBV-DNA viral load (EBV VL) monitoring strategy, including the reduction of immunosuppression, has led to a lower incidence of PTLD. For adult LT recipients with less primary infection and more EBV reactivation, it is unknown whether this strategy is effective.

OBJECTIVE

To examine the effect of an EBV VL monitoring strategy on the incidence of PTLD after LT in adults.

DESIGN

Cohort study.

SETTING

Two university medical centers in the Netherlands.

PATIENTS

Adult recipients of first LT in Leiden between September 2003 and January 2017 with an EBV VL monitoring strategy formed the monitoring group (M1), recipients of first LT in Rotterdam between January 2003 and January 2017 without such a strategy formed the contemporary control group (C1), and those who had transplants in Leiden between September 1992 and September 2003 or Rotterdam between 1986 and January 2003 formed the historical control groups (M0 and C0, respectively).

MEASUREMENTS

Influence of EBV VL monitoring on incidence of PTLD.

RESULTS

After inverse probability of treatment weighting of the 4 groups to achieve a balance among the groups for important patient characteristics, differences within hospitals between the historical and recent era in cumulative incidences-expressed as the number of events per 1000 patients measured at 5-, 10-, and 15-year follow-up-showed fewer events in the contemporary era in both centers. This difference was considerably larger in the monitoring center, whereas the 95% CI included the null value of 0 for point estimates.

LIMITATION

Retrospective, low statistical power, and incompletely balanced groups, and non-EBV PTLD cannot be prevented.

CONCLUSION

Monitoring EBV VL may reduce PTLD incidence after LT in adults; larger studies are warranted.

PRIMARY FUNDING SOURCE

None.

The impact of chronic Epstein-Barr virus infection on the liver graft of pediatric liver transplant recipients: A retrospective observational study

BACKGROUND

Chronic high Epstein-Barr virus loads (CHEBV) are commonly observed in pediatric liver transplant patients. However, it is unclear how CHEBV impacts the liver graft. The aim of this study was to clarify the clinical and pathological impacts of CHEBV on the liver graft.

METHODS

From 2012 to 2020, we retrospectively investigated 46 pediatric liver transplant patients (under 16 years) who survived ≥6 months. The patients were divided into two groups: CHEBV group (EBV DNA >10 000 IU/ml of whole blood for ≥6 months) and nonchronic high EBV (NCHEBV) group (patients who did not meet CHEBV criteria). Tacrolimus was reduced to <3.0 ng/ml in patients with EBV DNA >5000 IU/ml. Blood biochemistry data and pathological findings, obtained at the time of protocol and episodic biopsies, were compared between the two groups.

RESULTS

Out of 46 patients, 28 CHEBV and 18 NCHEBV patients were enrolled. The blood biochemical examination did not show a significant difference between the two groups. In addition, no significant differences between the two groups were found in the pathological findings, including frequency of late acute rejection and the progression of fibrosis at the time of both protocol and episodic biopsies. Appropriate adjustment of immunosuppression for CHEBV management may have contributed to the prevention of the progression of fibrosis.

CONCLUSION

CHEBV had little adverse effect on the liver graft. Graft fibrosis might have been avoided through optimal dose modification of tacrolimus. Further long-term monitoring is necessary because CHEBV may affect the pediatric liver graft in the long term.

Classic Hodgkin lymphoma post-transplant lymphoproliferative disorders (PTLD) are often preceded by discordant PTLD subtypes

Classic Hodgkin lymphoma (CHL) is the rarest post-transplant lymphoproliferative disorder (PTLD) subtype. Few cases of patients with metachronous discordant PTLD episodes including CHL-PTLD have been reported, but the incidence of and risk factors for this phenomenon are unknown. Patients with CHL-PTLD were identified from an institutional PTLD database. Of 13 patients identified with CHL-PTLD six (46%) had antecedent non-CHL-PTLD: three had polymorphic PTLD, two monomorphic PTLD, and one nondestructive PTLD. Patients with prior metachronous non-CHL-PTLD were younger at transplant and had a longer latency time to CHL-PTLD post-transplant. The prevalence of EBV seronegativity at transplant was high in both groups, but prolonged high-level EBV DNAemia only occurred in some with metachronous non-CHL-PTLD. In conclusion, patients with CHL-PTLD have metachronous non-CHL-PTLD diagnoses with discordant histology more commonly than previously recognized. Primary EBV infection with chronically elevated EBV viral loads may represent unique risk factors for CHL-PTLD following an initial non-CHL-PTLD event.

Post-transplant lymphoproliferative disorders, Epstein-Barr virus infection, and disease in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

PTLD with the response-dependent sequential use of RIS, rituximab, and cytotoxic chemotherapy is recommended. Evidence gaps requiring future research and alternate treatment strategies including immunotherapy are highlighted.