(Val-)Ganciclovir prophylaxis reduces Epstein-Barr virus primary infection in pediatric renal transplantation

Treatment of Epstein-Barr Virus infection in immunocompromised patients

Epstein-Barr Virus (EBV), is a ubiquitous γ-Herpesvirus that infects over 95% of the human population and can establish a life-long infection without causing any clinical symptoms in healthy individuals by residing in memory B-cells. Primary infection occurs in childhood and is mostly asymptomatic, however in some young adults it can result in infectious mononucleosis (IM). In immunocompromised individuals however, EBV infection has been associated with many different malignancies. Since EBV can infect both epithelial and B-cells and very rarely NK cells and T-cells, it is associated with both epithelial cancers like nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC), with lymphomas including Burkitt Lymphoma (BL) or Post-transplant Lymphoproliferative Disorder (PTLD) and rarely with NK/T-cell lymphomas. Currently there are no approved antivirals active in PTLD nor in any other malignancy. Moreover, lytic phase disease almost never requires antiviral treatment. Although many novel therapies against EBV have been described, the management and/or prevention of EBV primary infections or reactivations remains difficult. In this review, we discuss EBV infection, therapies targeting EBV in both lytic and latent state with novel therapeutics developed that show anti-EBV activity as well as EBV-associated malignancies both, epithelial and lymphoproliferative malignancies and emerging therapies targeting the EBV-infected cells.

A Focused Review of Epstein-Barr Virus Infections and PTLD in Pediatric Transplant Recipients: Guidance From the IPTA and ECIL Guidelines

Epstein-Barr Virus (EBV) diseases, including EBV-associated post-transplant lymphoproliferative disorder (PTLD) remain important causes of morbidity and mortality in children undergoing solid organ transplantation (SOT) and hematopoietic cell transplantation (HCT). Despite progress in the prevention of EBV disease including PTLD (EBV/PTLD) in HCT, key questions in the prevention, and management of these infectious complications remain unanswered. The goal of this manuscript is to highlight key points and recommendations derived from the consensus guidelines published by the International Pediatric Transplant Association and the European Conference on Infections in Leukemia for children undergoing SOT and HCT, respectively. Additionally, we provide background and guidance on the use of EBV viral load measurement in the prevention and management of these children.

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.

Post-Transplant Lymphoproliferative Disorders

Post-transplant lymphoproliferative disorders (PTLDs) are a heterogenous set of unregulated lymphoid cell proliferations after organ or tissue transplant. A majority of cases are associated with the Epstein-Barr virus and higher intensity of pharmacologic immunosuppression. The clinical presentations are numerous. The diagnosis is ideally by histology, except in cases where the tumor is inaccessible to biopsy. While some pre-emptive therapies and treatment strategies are available have reasonable success are available, they do not eliminate the high morbidity and significant mortality after PTLD.

Prevention of Oncogenic Gammaherpesvirinae (EBV and HHV8) Associated Disease in Solid Organ Transplant Recipients

Long-term risk for malignancy is higher among solid organ transplant (SOT) recipients compared to the general population. Four non-hepatitis viruses have been recognized as oncogenic in SOT recipients-EBV, cause of EBV-associated lymphoproliferative diseases; human herpes virus 8 (HHV8), cause of Kaposi sarcoma, primary effusion lymphoma and multicentric Castleman disease; human papilloma virus, cause of squamous cell skin cancers, and Merkel cell polyomavirus, cause of Merkel cell carcinoma. Two of these viruses (EBV and HHV8) belong to the human herpes virus family. In this review, we will discuss key aspects regarding the clinical presentation, diagnosis, treatment, and prevention of diseases in SOT recipients associated with the two herpesviruses.

Screening and Management of PTLD

Posttransplant lymphoproliferative disorder (PTLD) represents a heterogeneous group of lymphoproliferative diseases occurring in the setting of immunosuppression following hematopoietic stem cells transplant and solid organ transplantation. Despite its overall low incidence, PTLD is a serious complication following transplantation, with a mortality rate as high as 50% in transplant recipients. Therefore, it is important to establish for each transplant recipient a personalized risk evaluation for the development of PTLD based on the determination of Epstein-Barr virus serostatus and viral load following the initiation of immunosuppression. Due to the dynamic progression of PTLD, reflected in the diverse pathological features, different therapeutic approaches have been used to treat this disorder. Moreover, new therapeutic strategies based on the administration of virus-specific cytotoxic T cells have been developed. In this review, we summarize the available data on screening and treatment to suggest a strategy to identify transplant recipients at a higher risk for PTLD development and to review the current therapeutic options for PTLD.

A quick algorithmic review on management of viral infectious diseases in pediatric solid organ transplant recipients

Pediatric solid organ transplant is a life-saving procedure for children with end-stage organ failure. Viral infections are a common complication following pediatric solid organ transplantation (SOT), which can lead to increased morbidity and mortality. Pediatric solid organ transplant recipients are at an increased risk of viral infections due to their immunosuppressed state. The most commonly encountered viruses include cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV), varicella-zoster virus (VZV), adenoviruses, and BK polyomavirus. Prevention strategies include vaccination prior to transplantation, post-transplant prophylaxis with antiviral agents, and preemptive therapy. Treatment options vary depending on the virus and may include antiviral therapy and sometimes immunosuppression modification. This review provides a Quick Algorithmic overview of prevention and treatment strategies for viral infectious diseases in pediatric solid organ transplant recipient.

Epstein-Barr virus-associated risk factors for post-transplant lymphoproliferative disease in pediatric liver transplant recipients

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) are the most common de novo malignancies after liver transplantation (LT) in children. The aim of our study was to assess the role of pre-LT EBV status and post-LT EBV viral load as risk factors for developing PTLD in a cohort of pediatric LT recipients.

METHODS

Data of all children who underwent LT between January 2002 and December 2019 were collected. Two cohorts were built EBV pre-LT primary infected cohort and EBV post-LT primary infected cohort. Moreover, using the maximal EBV viral load, a ROC curve was constructed to find a cutoff point for the diagnosis of PTLD.

RESULTS

Among the 251 patients included in the study, fifteen PTLD episodes in 14 LT recipients were detected (2 plasmacytic hyperplasia, 10 polymorphic PTLD, 2 monomorphic PTLD, and 1 Classical-Hodgkin's lymphoma). Patients of the EBV post-LT primary infected cohort were 17.1 times more likely to develop a PTLD than patients of the EBV pre-LT primary infected cohort (2.2-133.5). The EBV viral load value to predict PTLD was set at 211 000 UI/mL (93.3% sensitivity and 77.1% specificity; AUC 93.8%; IC 0.89-0.98). In EBV post-LT primary infected cohort, patients with a viral load above 211 000 were 30 times more likely to develop PTLD than patients with a viral load below this value (OR 29.8; 3.7-241.1; p < 0.001).

CONCLUSIONS

The combination of pretransplant EBV serological status with EBV post-transplant viral load could be a powerful tool to stratify the risk of PTLD in pediatric LT patients.

Non-Hodgkin lymphoma after pediatric kidney transplantation

Non-Hodgkin lymphoma (NHL) that develops after kidney transplantation belongs to post-transplant lymphoproliferative disorders (PTLD) occurring with an incidence of 2-3%. Most pediatric cases are related to primary infection with Epstein-Barr virus (EBV), able to transform and immortalize B cells and widely proliferate due to the lack of relevant control of cytotoxic T cells in patients receiving post-transplant immunosuppression. NHL may develop as a systemic disease or as a localized lesion. The clinical pattern is variable, from non-symptomatic to fulminating disease. Young age of transplant recipient, seronegative EBV status at transplantation, and EBV mismatch between donor and recipient (D+/R-) are regarded as risk factors. Immunosuppression impacts the development of both early and late NHLs. Specific surveillance protocols, including monitoring of EBV viral load, are used in patients at risk; however, detailed histopathology diagnosis and evaluation of malignancy staging is crucial for therapeutic decisions. Minimizing of immunosuppression is a primary management, followed by the use of rituximab in B-cell NHLs. Specific chemotherapeutic protocols, adjusted to lymphoma classification and staging, are used in advanced NHLs. Radiotherapy and/or surgical removal of malignant lesions is limited to the most severe cases. Outcome is variable, depending on risk factors and timing of diagnosis, however is positive in pediatric patients in terms of graft function and patient survival. Kidney re-transplantation is possible in survivors who lost the primary graft due to chronic rejection, however may be performed after at least 2-3 years of waiting time, careful verification of malignancy-free status, and gaining immunity against EBV.

Pediatric Onco-Nephrology: Time to Spread the Word-Part II: Long-Term Kidney Outcomes in Survivors of Childhood Malignancy and Malignancy after Kidney Transplant

Onco-nephrology is a recent and evolving medical subspecialty devoted to the care of patients with kidney disease and unique kidney-related complications in the context of cancer and its treatments, recognizing that management of kidney disease as well as the cancer itself will improve survival and quality of life. While this area has received much attention in the adult medicine sphere, similar emphasis in the pediatric realm has not yet been realized. As in adults, kidney involvement in children with cancer extends beyond the time of initial diagnosis and treatment. Many interventions, such as chemotherapy, stem cell transplant, radiation, and nephrectomy, have long-term kidney effects, including the development of chronic kidney disease (CKD) with subsequent need for dialysis and/or kidney transplant. Thus, with the improved survival of children with malignancy comes the need for ongoing monitoring of kidney function and early mitigation of kidney-related comorbidities. In addition, children with kidney transplant are at higher risk of developing malignancies than their age-matched peers. Pediatric nephrologists thus need to be aware of issues related to cancer and its treatments as they impact their own patients. These facts emphasize the necessity of pediatric nephrologists and oncologists working closely together in managing these children and highlight the importance of bringing the onco-nephrology field to our growing list of pediatric nephrology subspecialties.

EBV, CMV, and BK viral infections in pediatric kidney transplantation: Frequency, risk factors, treatment, and outcomes

BACKGROUND

Improved short- and long-term outcomes of kidney transplantation have been achieved over the past decades due to improved immunosuppression. This may have increased the risk for infections and, particularly, for the viral infections: cytomegalovirus (CMV), Epstein-Barr virus (EBV), and polyoma BK virus (BKV).

METHODS

A retrospective review of viremic CMV, EBV, and BKV infections in pediatric renal transplant recipients treated and followed by a national referral center over a 10-year period.

RESULTS

Sixty-seven patients (68% males) received 68 kidney grafts (62% from living donors) during the study period; the mean follow-up period was 5.2 ± 2.4 years. Twenty-seven viremic episodes were documented (CMV: 13, EBV: 6, BKV: 8) in 24 patients (35.2%). The median time (interquartile range) to viremia post-transplant was 11 (4-38) months. The viral infection rate was significantly higher in the years 2014-2015 than in previous years (61% vs. 29%, p = .017). Compared to patients who did not develop viremia, patients with viremias were younger at the time of transplantation, were more likely to receive thymoglobulin induction pre-transplant and to develop an acute rejection. Multiple logistic regression modeling identified transplant year and recipient's age as significant risk factors for viremia. Graft outcome and eGFR at the last follow-up was similar between patients who did and did not develop viremia.

CONCLUSIONS

Viral infections continue to be a major cause of morbidity in pediatric kidney transplant recipients. However, with close monitoring and prompt intervention, patient and renal outcomes remain favorable.

EBV-associated diseases: Current therapeutics and emerging technologies

EBV is a prevalent virus, infecting >90% of the world's population. This is an oncogenic virus that causes ~200,000 cancer-related deaths annually. It is, in addition, a significant contributor to the burden of autoimmune diseases. Thus, EBV represents a significant public health burden. Upon infection, EBV remains dormant in host cells for long periods of time. However, the presence or episodic reactivation of the virus increases the risk of transforming healthy cells to malignant cells that routinely escape host immune surveillance or of producing pathogenic autoantibodies. Cancers caused by EBV display distinct molecular behaviors compared to those of the same tissue type that are not caused by EBV, presenting opportunities for targeted treatments. Despite some encouraging results from exploration of vaccines, antiviral agents and immune- and cell-based treatments, the efficacy and safety of most therapeutics remain unclear. Here, we provide an up-to-date review focusing on underlying immune and environmental mechanisms, current therapeutics and vaccines, animal models and emerging technologies to study EBV-associated diseases that may help provide insights for the development of novel effective treatments.

Epstein-Barr virus infection presenting as encephalitis in HIV—Phenomenon not seen frequently

Epstein-Barr virus (EBV) infection can rarely present as encephalitis in HIV patients. We report a case of a 22-year-old female patient, diagnosed to have HIV infection 8 years back. She presented with headache and altered behavior for a week and focal fits for 2 days. Neurological examination was unremarkable. Cerebrospinal fluid (CSF) examination revealed lymphocytic pleocytosis with raised protein. EBV was detected in CSF using polymerase chain reaction test. Magnetic resonance imaging of the brain revealed T2/fluid-attenuated inversion recovery hyperintensities involving the left frontal cortex, left thalamus, and right medial temporal cortex. The patient was started on antiviral therapy considering the diagnosis of EBV encephalitis. The patient completely recovered over the next few weeks.

Valganciclovir is not associated with decreased EBV infection rate in pediatric kidney transplantation

INTRODUCTION

Primary infection or reactivation of Epstein-Barr Virus (EBV) is a significant cause of morbidity and mortality in pediatric kidney transplantation. Valganciclovir (VGC) treatment is recommended for prophylaxis of cytomegalovirus infection, but its role for the prevention of EBV infection remains controversial.

PATIENTS AND METHODS

All pediatric kidney transplant recipients aged <18 years old were considered for inclusion in this retrospective study. EBV negative recipients with an EBV positive donor (a group at risk of primary infection) or EBV positive recipients (a group at risk of reactivation) were included. Severe infection was defined by post-transplant lymphoproliferative disorder (PTLD), symptomatic EBV infection or by asymptomatic EBV infection with a viral load >4.5 log/ml. Outcomes were compared between patients receiving VGC prophylaxis (group P+) and those not receiving VGC prophylaxis (group P-).

RESULTS

A total of 79 patients were included, 57 (72%) in the P+ group and 22 (28%) in the P- group; 25 (31%) were at risk of primary infection and 54 (69%) at risk of reactivation. During the first year post-transplant, the occurrence of severe EBV infection was not different between the P+ group (n = 13, 22.8%) and the P- group (n = 5, 22.7%) (p = 0.99). Among patients at risk of primary infection, the rate of severe EBV infection was not different between the two groups (42.1% in P+ vs. 33.3% in P-). A higher frequency of neutropenia was found in the P+ group (66.6%) than in the P- group (33.4%) (p < 0.01).

CONCLUSION

Our observational study suggests no effect of VGC for the prevention of EBV infection in pediatric kidney transplant recipients, irrespective of their EBV status. Adverse effects revealed an increased risk of neutropenia.

Use of Rituximab for persistent EBV DNAemia, and Its effect on donor-specific antibody development in pediatric renal transplant recipients: A case series

INTRODUCTION

Persistent EBV DNAemia (PEBV) is associated with late-onset PTLD. The efficacy of rituximab in PEBV is not conclusive. We monitored PEBV and DSA in pediatric kidney transplant patients with or without rituximab.

METHODS

13 PEBV patients received standard treatment with immunosuppression reduction and valganciclovir, with or without IVIG; 5/13 were further treated with rituximab.

RESULTS

All Rituximab-treated and 6/7 No-Rituximab patients were EBV seronegative at transplant and seroconverted post-transplant. Peak EBV PCR levels were lower in No-Rituximab than Rituximab patients and all No-Rituximab patients cleared PEBV after standard treatment. Additional 1-2 doses of rituximab reduced EBV PCR levels in all 5 Rituximab patients, 3 cleared PEBV. One No-Rituximab patient developed localized PLTD. None of Rituximab patients developed de novo DSA, while 4/8 No-Rituximab patients did: 2/4 had ABMR. 1/5 Rituximab and 5/8 No-Rituximab patients had acute rejection. There was no change in eGFR between pre-EBV DNAemia and follow-up in Rituximab patients, while reduction in No-Rituximab patients was found. There was no difference in graft and patient survival.

CONCLUSIONS

While early intervention with rituximab in pediatric patients with PEBV may reduce viral load and PTLD, we observed a slower development of de novo DSA, and rejection and maintenance of eGFR.

CMV, EBV, JCV and BKV infection and outcome following kidney transplantation in children initiated on a corticosteroid-minimisation immunosuppressive regimen

BACKGROUND

Modern immunosuppressive regimens in paediatric kidney transplant recipients have contributed to improved long-term allograft survival, but at the expense of an increased incidence of viral infections. Here, we describe, for the first time, the incidence, risk factors and clinical outcome of CMV, EBV, BKV and JCV viraemia in a cohort of paediatric allograft recipients treated with a corticosteroid-minimisation immunosuppressive regimen (CMR).

METHODS

We retrospectively analysed 98 children treated with a CMR (basiliximab induction, corticosteroids until day 4, long-term tacrolimus and mycophenolate mofetil), who received a kidney transplant in our centre between 2009 and 2019.

RESULTS

Over the first 4 years post-transplant, the incidences of viraemia were as follows: CMV, 25.5%; EBV, 52.0%; JCV, 16.3%; BKV, 26.5%. Younger children at time of transplant were more likely to develop EBV and BKV viraemia. EBV viraemia was also associated with a regimen involving corticosteroids, but lacking MMF. Recipient CMV serology predicted the development of EBV, BKV and CMV viraemia. Fifty-six percent of CMV viraemia episodes in high-risk patients occurred whilst the graft recipients were still receiving anti-viral prophylaxis or within 3 months of cessation. There was no difference in graft function at latest follow-up between those with and without viraemia.

CONCLUSIONS

Judicious monitoring of viraemia, coupled with timely clinical intervention, can result in similar long-term outcomes for graft recipients compared to controls. The high incidence of CMV viraemia observed within a short period of cessation of anti-viral prophylaxis supports an extension of the length of prophylactic treatment in high-risk allograft recipients.

EBV-specific cytotoxic T lymphocytes for refractory EBV-associated post-transplant lymphoproliferative disorder in solid organ transplant recipients: a systematic review

The use of Epstein-Barr virus-specific cytotoxic T lymphocytes (EBV-CTLs) in adoptive immunotherapy in hematopoietic stem cell transplantation (HSCT) patients with post-transplantation lymphoproliferative disorder (PTLD) has demonstrated safety and effectiveness. EBV-CTLs might also be the effective treatment of refractory PTLD of solid organ transplantation (SOT) recipients. Two independent assessors searched Pubmed, Embase, Cochrane Library, and Web of Science from their inception to November 2020. Eleven studies with 76 patients (42, 55% male) were included. We extracted the data and completed the quality assessments. Most of the studies were from Europe and the USA. Liver and kidney transplantation accounted for most of the transplant types. Thirty-five (46.1%) patients were diagnosed with monomorphic PTLD, and B lymphocyte type was the most common. All the patients received primary treatment for PTLD while it was ineffective. CTLs included autologous EBV-CTLs (15/76, 22%) and HLA-matched third-party EBV-CTLs (61/76, 78%). The response rate for EBV-CTL treatment of refractory PTLD was 66%. Of 50 patients, 36 achieved complete remission and 14 achieved partial remission. EBV-DNA level decreased in 39 patients. Adverse reactions were rare and mild. We conclude that adoptive therapy with EBV-specific CTLs is safe, well-tolerated, and effective in PTLD.

Malignancies after pediatric solid organ transplantation

As life expectancy among pediatric solid organ transplant recipients (SOTRs) improves, the risk of comorbid conditions such as malignancy post-transplantation has also increased. SOTRs are at elevated risks of post-transplantation lymphoproliferative disorders (PTLDs), and skin and solid cancers. PTLDs typically occur early following transplantation, while skin and solid cancers frequently arise in young adulthood (25-40 years). By 30 years following transplantation, 26-41% of pediatric SOTRs have developed cancer. Different risk factors exist for PTLD, and skin and solid cancers, which are modified by cumulative immunosuppression, infections, transplanted organ, and the underlying disease process associated with initial organ failure (e.g., kidney failure). Optimal cancer treatment strategies depend on the specific cancer type, stage, and patient comorbidities. Immunosuppression reduction may be beneficial for certain cancers but must be considered against the risks of acute and chronic rejection and allograft loss. Lifestyle counseling regarding smoking avoidance and sun protection, as well as human papillomavirus vaccination, is an important aspect of cancer prevention. Currently, no cancer screening guidelines exist specifically for pediatric SOTRs. Adult population screening guidelines have not been validated in transplant populations. Therefore, an individualized approach should be taken to cancer screening for pediatric SOTRs, accounting for other cancer risk factors.

Post-transplantation lymphoproliferative disorder after haematopoietic stem cell transplantation

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication of haematopoietic stem cell transplantation (HSCT), occurring in a setting of immune suppression and dysregulation. The disease is in most cases driven by the reactivation of the Epstein-Barr virus (EBV), which induces B cell proliferation through different pathomechanisms. Beyond EBV, many factors, variably dependent on HSCT-related immunosuppression, contribute to the disease development. PTLDs share several features with primary lymphomas, though clinical manifestations may be different, frequently depending on extranodal involvement. According to the WHO classification, histologic examination is required for diagnosis, allowing also to distinguish among PTLD subtypes. However, in cases of severe and abrupt presentation, a diagnosis based on a combination of imaging studies and EBV-load determination is accepted. Therapies include prophylactic and pre-emptive interventions, aimed at eradicating EBV proliferation before symptoms onset, and targeted treatments. Among them, rituximab has emerged as first-line option, possibly combined with a reduction of immunosuppression, while EBV-specific cytotoxic T lymphocytes are effective and safe alternatives. Though prognosis remains poor, survival has markedly improved following the adoption of the aforementioned treatments. The validation of innovative, combined approaches is the future challenge.

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.

Epidemiology of and Risk Factors for BK Polyomavirus Replication and Nephropathy in Pediatric Renal Transplant Recipients: An International CERTAIN Registry Study

BACKGROUND

BK polyomavirus-associated nephropathy (BKPyVAN) constitutes a serious cause of kidney allograft failure, but large-scale data in pediatric renal transplant recipients and a comprehensive analysis of specific risk factors are lacking.

METHODS

We analyzed the data of 313 patients in the Cooperative European Pediatric Renal Transplant Initiative Registry, with an observation period of 3.3 years (range, 1-5). The net state of immunosuppressive therapy was assessed by the modified Vasudev score.

RESULTS

Presumptive BKPyVAN (defined as sustained [>3 wk] high-level BK viremia >10 copies/mL) within 5 years posttransplant occurred in 49 (15.8%) of 311 patients, and biopsy-proven BKPyVAN in 14 (4.5%) of 313. BKPyV viremia was observed in 115 (36.7%) of 311 patients, of whom 11 (9.6%) of 115 developed viremia late, that is, after the second year posttransplant. In 6 (12.5%) of 48 patients with high-level viremia and in 3 (21.4%) of 14 with BKPyVAN, this respective event occurred late. According to multivariable analysis, BKPyV viremia and/or BKPyVAN were associated not only with a higher net state of immunosuppression (odds ratio [OR], 1.3; P < 0.01) and with tacrolimus-based versus ciclosporin-based immunosuppression (OR, 3.6; P < 0.01) but also with younger recipient age (OR, 1.1 per y younger; P < 0.001) and obstructive uropathy (OR, 12.4; P < 0.01) as primary renal disease.

CONCLUSIONS

Uncontrolled BKPyV replication affects a significant proportion of pediatric renal transplant recipients and is associated with unique features of epidemiology and risk factors, such as young recipient age, obstructive uropathy, and overall intensity of immunosuppressive therapy. BKPyV surveillance should be considered beyond 2 years posttransplant in pediatric patients at higher risk.

Valganciclovir prophylaxis delays onset of EBV viremia in high-risk pediatric solid organ transplant recipients

BACKGROUND

The role of antiviral prophylaxis to prevent Epstein-Barr virus (EBV) viremia or posttransplant lymphoproliferative disorder in pediatric solid organ transplant recipients is controversial. We examined whether valganciclovir (VAL) prophylaxis for cytomegalovirus infection was associated with EBV viremia following transplantation in EBV-naive children.

METHODS

A single-center, retrospective study was conducted of EBV-naive pediatric heart and renal transplant recipients with an EBV-positive donor from January 1996 to April 2017. VAL was tested for association with EBV viremia-free survival in the first 6 months posttransplantation when immunosuppressant exposure is the highest. Survival models evaluated VAL duration, with adjustment for other baseline confounders.

RESULTS

Among the cohort (n = 44), 3 (6.8%) were heart transplants, 25 (56.8%) received VAL, and 22 (50%) developed EBV viremia in the first-year posttransplantation. Mean time-to-viremia was 143 vs. 90 days for the VAL and no-VAL groups, respectively (p = 0.008), in the first 6 months. Only two patients developed viremia while on VAL. Each additional day of VAL was associated with 1.4% increase in viremia-free survival (p < 0.001). Multivariable modeling of VAL with other baseline risk factors did not identify other independent risk factors.

CONCLUSION

VAL is independently associated with delayed onset of EBV viremia, with prolongation of delay with each additional day of antiviral prophylaxis.

Long-lasting chronic high load carriage of Epstein-Barr virus is more common in young pediatric renal transplant recipients

BACKGROUND

Epstein-Barr virus (EBV) infections can induce post-transplant lymphoproliferative disorder (PTLD). A chronic high load (CHL), as indicated by long-term high EBV DNA levels after transplantation, has been associated with an enhanced risk of PTLD. We aimed to evaluate incidence, time of occurrence, risk factors, and outcome of EBV CHL carrier state after pediatric renal transplantation.

METHODS

A retrospective study of 58 children aged 1-17 years (median 10), who underwent renal transplantation between January 2004 and June 2017 at a single medical center. EBV IgG antibodies in serum were analyzed before and yearly after transplantation. EBV DNA in whole blood were analyzed weekly for the first 3 months post-transplant, monthly up to 1 year and then at least once yearly. CHL was defined as EBV DNA ≥ 4.2 log₁₀ Geq/ml in > 50% of the samples during ≥ 6 months.

RESULTS

At transplantation, 31 (53%) patients lacked EBV IgG and 25 (81%) of them developed primary EBV infection post-transplant. Of the 27 seropositive patients, 20 (74%) experienced reactivation of EBV. Altogether, 14 (24%) children developed CHL, starting at a median of 69 days post-transplant and lasting for a median time of 2.3 years (range 0.5-6.5), despite reduction of immunosuppression. Patients with CHL were younger and 11/14 were EBV seronegative at transplantation. No child developed PTLD during median clinical follow-up of 7.8 years (range 0.7-13).

CONCLUSIONS

CHL was frequent, long lasting, and occurred mainly in young transplant recipients. The absence of PTLD suggests that monitoring of EBV DNA to guide immunosuppression was effective.

Dipyridamole as a new drug to prevent Epstein-Barr virus reactivation

Epstein-Barr virus (EBV) is a widely distributed gamma-herpesvirus that has been associated with various cancers mainly from lymphocytic and epithelial origin. Although EBV-mediated oncogenesis has been associated with viral oncogenes expressed during latency, a growing set of evidence suggested that antiviral treatments directed against EBV lytic phase may contribute to prevent some forms of cancers, including EBV-positive Post-Transplant Lymphoproliferative Diseases. It is shown here that dipyridamole (DIP), a safe drug with favorable and broad pharmacological properties, inhibits EBV reactivation from B-cell lines. DIP repressed immediate early and early genes expression mostly through its ability to inhibit nucleoside uptake. Considering its wide clinical use, DIP repurposing could shortly be evaluated, alone or in combination with other antivirals, to treat EBV-related diseases where lytic replication plays a deleterious role.

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.

Cytomegalovirus and Epstein-Barr virus infections among pediatric kidney transplant recipients at a center using universal Valganciclovir Prophylaxis

BACKGROUND

CMV is associated with adverse effects in renal transplant recipients. The objective of this study was to characterize the incidence and timing of CMV and EBV infections in relation to valGCV prophylaxis in a pediatric renal transplant cohort.

METHODS

Retrospective cohort of pediatric renal transplant patients given universal valGCV prophylaxis and universal viral surveillance was evaluated. Demographics, prophylaxis, acute rejection, and CMV and EBV infections were abstracted.

RESULTS

A total of 92 pediatric renal allograft recipients, 2008-2013, were included. One or more viral infections developed in 77/92 (83.7%) of the patients. EBV was the most common in 62/92 (67%) patients, irrespective of valGCV (82% of episodes occurring on valGCV). CMV DNAemia occurred in 30/92 (33%) patients, 14 episodes (47%) occurring on valGCV. Incidence of breakthrough CMV on prophylaxis was 15% and was associated with persistent DNAemia (OR 7.8, CI:1.6-32.9, P < 0.02). CMV tissue-invasive disease was not seen. CMV syndrome occurred in 10% of the cohort, only in CMV D+ patients, and only one symptomatic breakthrough infection required treatment. Out of 92, 21 (23%) had simultaneous co-infections with 2-3 viruses.

CONCLUSIONS

Viral infections in pediatric renal transplant recipients receiving universal valGCV prophylaxis were common. EBV infections were not reduced by valGCV prophylaxis, and nearly half of CMV infections occurred on valGCV. Symptomatic CMV infection while on prophylaxis was rare. valGCV prophylaxis may prevent symptomatic CMV infection but not EBV infection, and frequent CMV surveillance in pediatric renal transplant recipients on prophylaxis may not be necessary.

Novel Therapeutics for Epstein⁻Barr Virus

Epstein–Barr virus (EBV) is a human γ-herpesvirus that infects up to 95% of the adult population. Primary EBV infection usually occurs during childhood and is generally asymptomatic, though the virus can cause infectious mononucleosis in 35–50% of the cases when infection occurs later in life. EBV infects mainly B-cells and epithelial cells, establishing latency in resting memory B-cells and possibly also in epithelial cells. EBV is recognized as an oncogenic virus but in immunocompetent hosts, EBV reactivation is controlled by the immune response preventing transformation in vivo. Under immunosuppression, regardless of the cause, the immune system can lose control of EBV replication, which may result in the appearance of neoplasms. The primary malignancies related to EBV are B-cell lymphomas and nasopharyngeal carcinoma, which reflects the primary cell targets of viral infection in vivo. Although a number of antivirals were proven to inhibit EBV replication in vitro, they had limited success in the clinic and to date no antiviral drug has been approved for the treatment of EBV infections. We review here the antiviral drugs that have been evaluated in the clinic to treat EBV infections and discuss novel molecules with anti-EBV activity under investigation as well as new strategies to treat EBV-related diseases.

JC polyomavirus replication and associated disease in pediatric renal transplantation: an international CERTAIN Registry study

BACKGROUND

JC polyomavirus (JCPyV)-associated nephropathy (JCPyVAN) is a severe, but rare complication in adult renal transplant (RTx) recipients. Related data in pediatric patients are scarce.

METHODS

Based on the CERTAIN Registry, we therefore performed a multi-center, retrospective study on the JCPyV antibody status, prevalence of JCPyV replication, and its associated disease in 139 pediatric RTx recipients (mean age, 8.5 ± 5.3 years). JCPyV DNA in plasma and/or urine was measured by quantitative PCR at a median time of 3.2 (IQR, 0.3-8.1) years post-transplant.

RESULTS

53.2% of patients were JCPyV-seronegative prior to transplantation; younger age was associated with JCPyV seronegativity. 34/139 (24.5%) patients post-transplant showed active JCPyV replication in either urine (22.0%), plasma (13.4%), or both (7.6%). JCPyV viremia occurred significantly (p < 0.001) more often in patients with viruria (34.6%) than in those without (7.6%), but 7/118 (5.9%) had isolated viremia. High-level viruria (> 10⁷ copies/mL) was found in 29.6% of viruric patients. A higher net state of immunosuppression constituted an independent risk factor for JCPyV replication both in urine and plasma (OR 1.2, p < 0.02). Male patients tended to have a higher risk of JCPyV viremia than females (OR 4.3, p = 0.057). There was one male patient (0.7%) with JCPyVAN 7 years post-transplant, which resolved after reduction of immunosuppressive therapy. No patient exhibited progressive multifocal leukoencephalopathy.

CONCLUSIONS

This first multi-center study on JCPyV in pediatric renal transplant recipients shows that JCPyV replication is common (24.5%), with strong immunosuppression being a significant risk factor, but associated nephropathy is rare.

Antiviral Drugs for EBV

Epstein–Barr virus (EBV) infects up to 95% of the adult human population, with primary infection typically occurring during childhood and usually asymptomatic. However, EBV can cause infectious mononucleosis in approximately 35–50% cases when infection occurs during adolescence and early adulthood. Epstein–Barr virus is also associated with several B-cell malignancies including Burkitt lymphoma, Hodgkin lymphoma, and post-transplant lymphoproliferative disease. A number of antiviral drugs have proven to be effective inhibitors of EBV replication, yet have resulted in limited success clinically, and none of them has been approved for treatment of EBV infections.

Pediatric renal transplantation: A retrospective single-center study on epidemiology and morbidity due to EBV

Pediatric R-Tx patients are at high risk of developing EBV primary infection. Although high DNA replication is a risk factor for PTLD, some patients develop PTLD with low viral load. In this retrospective single-center study including all pediatric patients having received R-Tx (2003-2012 period), we aimed to identify risk factors for uncontrolled reactions to EBV (defined as the presence of a viral load >10 000 copies/mL or PTLD). A Cox proportional hazard model was performed. A total of 117 patients underwent R-Tx at a mean age of 9.7 ± 5.3 years, 46 of them being seronegative for EBV at the time of R-Tx. During follow-up, 54 patients displayed positive EBV viral load, 22 of whom presenting with primary infection. An uncontrolled reaction to EBV was observed in 24 patients, whilst 4 patients developed PTLD. Univariate and multivariate analyses suggested the following risk factors for an uncontrolled reaction: age below 5 years, graft from a deceased donor, ≥5 HLA mismatches, EBV-seronegative status at the time of R-Tx, and a secondary post-Tx loss of anti-EBNA. Monitoring anti-EBNA after R-Tx may contribute to the early identification of patients at risk for uncontrolled reaction.

Comprehensive review of post-organ transplant hematologic cancers

A higher risk for a variety of cancers is among the major complications of posttransplantation immunosuppression. In this part of a continuing series on cancers posttransplantation, this review focuses on the hematologic cancers after solid organ transplantation. Posttransplantation lymphoproliferative disorders (PTLDs), which comprise the great majority of hematologic cancers, represent a spectrum of conditions that include, but are not limited to, the Hodgkin and non-Hodgkin lymphomas. The oncogenic Epstein-Barr virus is a key pathogenic driver in many PTLD cases, through known and unknown mechanisms. The other hematologic cancers include leukemias and plasma cell neoplasms (multiple myeloma and plasmacytoma). Clinical features vary across malignancies and location. Preventive screening strategies have been attempted mainly for PTLDs. Treatments include the chemotherapy regimens for the specific cancers, but also include reduction of immunosuppression, rituximab, and other therapies.

Epstein-Barr virus lymphoproliferative disease after solid organ transplantation

Epstein-Barr virus (EBV) was the first identified human oncovirus and is also one of the most ubiquitous viral infections known with established infections in more than 90% of individuals by early adulthood. EBV establishes latency by controlling expression of the viral genome making it silent to immune surveillance. In immunocompetent individuals, up to 1% of circulating T cells are directed at maintaining control over EBV replication. In addition to being involved in oncogenesis of lymphoid and epithelial tumors in immune-competent individuals, loss of immune surveillance over EBV predisposes individuals to EBV malignancies. Lymphoid proliferations from EBV-infected B cells arise in up to 20% of recipients of solid organ transplants (SOTs). One question not answered is why, when EBV requires such active immune surveillance, EBV malignancies are not even more prevalent in severely immune-compromised individuals. A better understanding of who develops complications related to EBV and what the immunologic risks are will ultimately make it feasible to perform prophylactic trials in those at highest risk. This review summarizes our current understanding of factors in SOT recipients that predispose them to the development of an EBV malignancy and that predict response to initial therapy. We then review the current landscape of those therapies, focusing on the goal of restoring long-term EBV-directed immunity to patients at risk.

No effect of treatment with intravenous ganciclovir on Epstein-Barr virus viremia demonstrated after pediatric liver transplantation

EBV after pediatric LT is a risk factor for PTLD. We wanted to evaluate the effect of intravenous ganciclovir on EBV viremia and to identify risk factors for chronic EBV viremia. All pediatric patients who underwent LT in Norway from 2002 until 2015 were reviewed. Twenty-two of 38 patients with viremia were treated with intravenous ganciclovir for a median of 22 (21-38) days. Treated and untreated patients were not different with respect to EBV seroconversion prior to transplantation or age at transplantation, but treated patients had significantly earlier viremia after transplantation (P=.005). There was no difference in the proportion of patients with reduction in virus load in patients treated with ganciclovir compared to untreated patients at 8 weeks. After 1 year, five of 19 patients treated with ganciclovir and six of 14 untreated patients had reduced virus load compared to start of viremia (P=.27). In conclusion, treatment with intravenous ganciclovir did not change the proportion of patients with reduction in EBV load at 8 weeks and 1 year after viremia. Younger age at transplantation, short time from transplantation to viremia, and lack of EBV seroconversion prior to transplantation were significant predictors of chronic EBV viremia.

Viral load of EBV DNAemia is a predictor of EBV-related post-transplant lymphoproliferative disorders in pediatric renal transplant recipients

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) is a severe complication of solid organ transplantation that can be classified into two major subtypes, namely, early lesions and non-early lesions, based on histopathological findings. In the vast majority of cases, proliferating cells are B lymphocytes and, most frequently, proliferation is induced by Epstein-Barr virus (EBV) infection.

METHODS

The aim of our study was to evaluate the natural history of EBV infection and its possible evolution toward PTLD in a pediatric cohort of patients who received a renal transplant between January 2000 and December 2013. A total of 304 patients were evaluated for this study, of whom 103 tested seronegative for EBV at transplantation.

RESULTS

Following transplantation, 50 of the 103 seronegative patients (48.5%) developed a first EBV infection, based on the results of PCR assays for EBV DNA, with 19 of these patients ultimately reverting to the negative state (<3000 copies/ml). Among the 201 seropositive patients only 40 (19.9%) presented a reactivation of EBV. Non-early lesions PTLD was diagnosed in ten patients, and early lesions PTLD was diagnosed in five patients. In all cases a positive EBV viral load had been detected at some stage of the follow-up. Having a maximum peak of EBV viral load above the median value observed in the whole cohort (59,909.5 copies/ml) was a significant and independent predictor of non-early lesions PTLD and all PTLD onset.

CONCLUSIONS

A high PCR EBV viral load is correlated with the probability of developing PTLD. The definition of a reliable marker is essential to identify patients more at risk of PTLD and to personalize the clinical approach to the single patient.

Infection rates in tacrolimus versus cyclosporine-treated pediatric kidney transplant recipients on a rapid discontinuation of prednisone protocol: 1-year analysis

AR is lower in pKTx recipients on Tac vs CsA. Data comparing infection outcomes for children treated with these agents are limited. We retrospectively studied infection outcomes in 96 pKTx recipients on a RDP. PS, DCGS, AR, and infection-free survival were assessed using Kaplan-Meier/log-rank tests and proportional hazards models. There were no differences in 1-year PS, DCGS, or AR between Tac and CsA recipients. After adjusting for AR, the hazard of CMV viremia was 4.0 times higher (95%CI: 1.04, 15.5; P = .044) and that of BK viremia was 3.8 times higher (95%CI: 1.5, 10.2; P = .007) in Tac recipients. The incidence of EBV viremia was similar between the groups (P = .56). PostTx lymphoproliferative disease was only observed in Tac recipients (3%). There was no difference in the incidence of pneumonia, urinary tract, or Clostridium difficile infections between Tac and CsA recipients. Among KTx recipients on RDP, the hazards of CMV and BK viremia within 1 year post-KTx were significantly higher in Tac recipients compared to CsA. Regular assessment for infections and lower Tac trough levels may be warranted in Tac recipients.

Increased risk of PTLD in lung transplant recipients with cystic fibrosis

BACKGROUND

Post-transplant lymphoproliferative disease (PTLD) is an important cause of morbidity and mortality following lung transplantation. Recipients with cystic fibrosis (CF) may have an increased risk of PTLD although the literature is limited to single center cohorts. Our primary aim is to examine PTLD in an adult lung transplant population by utilizing the International Society for Heart and Lung Transplantation Registry.

METHODS

We studied 30,598 adult recipients of lung transplants performed between 1999 and 2011. The primary outcome was development of and time to PTLD. In addition to indication for transplant, other predictors examined included Epstein-Barr virus (EBV) and cytomegalovirus (CMV) serostatus, gender, and age. Outcomes were assessed with univariable and multivariable Cox proportional hazard models to obtain hazard ratios (HR).

RESULTS

17% of the cohort had a diagnosis of CF. PTLD developed in 2% of CF recipients compared to 1% for non-CF recipients (p<0.001). Compared to non-CF recipients, CF recipients had higher prevalence of EBV and CMV seronegativity and higher prevalences of high risk EBV and CMV mismatch (D+/R-). There is a significant association between CF and the development of PTLD [HR 1.66 (95% CI 1.30-2.12)]. Stratified multivariable analysis controlling for age revealed EBV negative non-CF recipients have an almost 2 fold increased risk of developing PTLD, whereas EBV negative CF recipients had an almost 6.5 fold increased risk.

CONCLUSIONS

CF recipients have a higher risk for PTLD compared to non-CF recipients. Further studies are needed to account for additional risk factors and management in this population post-transplant.

The efficacy of valganciclovir for prevention of infections with cytomegalovirus and Epstein-Barr virus after kidney transplant in children

This study evaluated the efficacy of prophylactic ValGCV in preventing CMV and EBV infections in a single-center pediatric kidney transplant population (2008-2014). Therapy duration was determined according to donor/recipient serostatus. EBV monitoring was performed using monthly plasma PCR for 18 months post-transplant and for CMV, monthly for 6 months after prophylaxis cessation. Data were collected on 35 children, median age 10.6 years. There were 15 (42.9%) and 11 (31.4%) recipients seronegative for CMV or EBV, respectively, who received a kidney from a seropositive donor. Prophylaxis was ceased by 6 months in 24 (69%), between seven and 13 months in 10 (29%) children. Fourteen (40%) and eight (23%) children experienced CMV and EBV DNAemia, respectively. Ten of the 14 (71%) episodes of CMV DNAemia occurred in the first 6 months following cessation of prophylaxis. Shorter prophylaxis was associated with increased CMV DNAemia (P = 0.044). There was an inverse correlation between adjusted ValGCV dose and EBV incidence/timing. Neutropenia was more common if ValGCV dosage was ≥10% of the dose predicted (by BSA and creatinine clearance). ValGCV prevents CMV and may modify EBV infection risk. Frequent dosing adjustment for BSA and creatinine clearance is required to optimize safety and efficacy.

Epstein-Barr virus and renal transplantation

Epstein-Barr virus (EBV) is a gamma herpesvirus associated with diseases ranging from asymptomatic viremia to post-transplant malignancies in kidney transplant recipients. EBV specifically is associated with post-transplantation lymphoproliferative disorder (PTLD), in kidney transplant recipients, with increased risk in EBV seronegative patients with EBV seropositive donors on intensified immunosuppression. The diagnosis of PTLD relies on clinical suspicion plus tissue biopsy with polymerase chain reaction (PCR) testing of blood currently used for risk determination in high-risk recipients. Therapeutic strategies for PTLD include reduction of immunosuppression, chemotherapy and rituximab, and consideration of sirolimus-based immunosuppression. Antivirals such as ganciclovir are used to prevent reactivation of cytomegalovirus and other herpes viruses but are not onco-therapeutic. Radiation therapy or surgery is indicated for bulky, disseminated or recalcitrant disease. Prognosis varies depending on the type of malignancy identified and stage of disease.

Biopsy-proven case of Epstein-Barr virus (EBV)-associated vasculitis of the central nervous system

A 75-year-old woman was admitted to our hospital with rapidly deteriorating consciousness disturbance. She had a 7-year history of rheumatoid arthritis (RA), which had been treated with methotrexate (MTX) and prednisolone. Brain T2-weighted MRI showed diffuse high-intensity lesions in the cerebral subcortical and deep white matter, bilateral basal ganglia and thalamus. A cerebrospinal fluid examination revealed elevated protein levels and positive Epstein-Barr virus (EBV) DNA. Human immunodeficiency virus was negative. Brain biopsy showed perivascular lymphocytic infiltration in the parenchyma and meninx with EBV-encoded small RNA (EBER). Since this case did not fulfill the criteria for chronic active EBV infection (CAEBV), she was diagnosed with Epstein-Barr virus (EBV)-associated vasculitis of the central nervous system. High-dose methylprednisolone, acyclovir, ganciclovir and foscarnet were not effective. Although EBV is a causative agent of infectious mononucleosis (IM), lymphomas and nasopharyngeal carcinomas, vasculitic pathology of the central nervous system with EBV reactivation in the elderly is rare. Immunosuppressive drugs such as steroids and MTX are widely used to treat autoimmune disorders, but may exacerbate the reactivation of EBV. This is the first case of biopsy-proven EBV-positive/HIV-negative vasculitis during the treatment of RA with MTX and steroids. This case indicates that EBV-associated vasculitis needs to be considered as a differential diagnosis of CNS vasculitis.

A Comparison of Two Types of Rabbit Antithymocyte Globulin Induction Therapy in Immunological High-Risk Kidney Recipients: A Prospective Randomized Control Study

Background

Induction treatment with rabbit polyclonal antithymocyte globulins (ATGs) is frequent used in kidney transplant recipients with donorspecific HLA antibodies and shows acceptable outcomes. The two commonly used ATGs, Thymoglobulin and ATG-F have slightly different antigen profile and antibody concentrations. The two compounds have never been directly compared in a prospective trial in immunological high-risk recipients. Therefore we performed a prospective randomized controlled study comparing the two compounds in immunological high-risk kidney recipients in terms of safety and efficacy.

Methods

Immunological high-risk kidney recipients, defined as the presence of HLA DSA but negative CDC-B and T-cell crossmatches were randomized 1:1 to receive ATG-F or Thymoglobulin. Maintenance immunosuppressive therapy consisted of tacrolimus, mycophenolate mofetil and steroids.

Results

The per-protocol analysis included 35 patients. There was no immediate infusion reaction observed with both compounds. No PTLD or malignancy occurred during the follow-up in both groups. The incidence of viral and bacterial infections was similar in both groups (p = 0.62). The cumulative incidence of clinical and subclinical antibody mediated allograft rejection as well as T-cell mediated allograft rejection during the first year between ATG-F and Thymoglobulin was similar (35% versus 19%; p = 0.30 and 11% versus 18%; 0.54 respectively). The two-year graft function was similar with a median eGFR of 56 ml/min/1.73m² (range 21–128) (ATG-F-group) and 51 ml/min/1.73m² (range 22–132) (Thymo-group) (p = 0.69).

Conclusion

We found no significant differences between the compared study drugs for induction treatment in immunological high-risk patients regarding safety and efficacy during follow-up with good allograft function at 2 years after transplantation.

The Epstein-Barr virus DNA load in the peripheral blood of transplant recipients does not accurately reflect the burden of infected cells

Transplant recipients frequently exhibit an increased Epstein-Barr virus (EBV) load in the peripheral blood. Here, we quantitated the EBV-infected cells in the peripheral blood of these patients and defined the mode of viral infection, latent or lytic. These data indicated that there is no strong correlation between the number of infected cells and the EBV load (EBVL). This can be explained by a highly variable number of EBV copies per infected cell and by lytic replication in some cells. The plasma of these patients did not contain any free infectious viruses, but contained nevertheless EBV DNA, sometimes in large amounts, that probably originates from cell debris and contributed to the total EBVL. Some of the investigated samples carried a highly variable number of infected cells in active latency, characterized by an expression of the Epstein-Barr nuclear antigens (EBNA2) protein. However, a third of the samples expressed neither EBNA2 nor lytic proteins. Patients with an increased EBVL represent a heterogeneous group of patients whose infection cannot be characterized by this method alone. Precise characterization of the origin of an increased EBVL, in particular, in terms of the number of EBV-infected cells, requires additional investigations including the number of EBV-encoded small RNA-positive cells.

Matched-pair analysis: identification of factors with independent influence on the development of PTLD after kidney or liver transplantation

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) adversely affects patients' long-term outcome.

METHODS

The paired t test and McNemar's test were applied in a retrospective 1:1 matched-pair analysis including 36 patients with PTLD and 36 patients without PTLD after kidney or liver transplantation. Matching criteria were age, gender, indication, type of transplantation, and duration of follow-up. All investigated PTLD specimen were histologically positive for EBV. Risk-adjusted multivariable regression analysis was used to identify independence of risk factors for PTLD detected in matched-pair analysis. The resultant prognostic model was assessed with ROC-curve analysis.

RESULTS

Patients suffering with PTLD had shorter mean survival (p = 0.004), more episodes of CMV infections or reactivations (p = 0.042), and fewer recipient HLA A2 haplotypes (p = 0.007), a tacrolimus-based immunosuppressive regimen (p = 0.052) and higher dosages of tacrolimus at hospital discharge (Tac dosage) (p = 0.052). Significant independent risk factors for PTLD were recipient HLA A2 (OR = 0.07, 95 % CI = 0.01-0.55, p = 0.011), higher Tac dosages (OR = 1.29, 95 % CI = 1.01-1.64, p = 0.040), and higher numbers of graft rejection episodes (OR = 0.38, 95 % CI = 0.17-0.87, p = 0.023). The following prognostic model for the prediction of PTLD demonstrated good model fit and a large area under the ROC curve (0.823): PTLD probability in % = Exp(y)/(1 + Exp(y)) with y = 0.671 - 1.096 × HLA A2-positive recipient + 0.151 × Tac dosage - 0.805 × number of graft rejection episodes.

CONCLUSIONS

This study suggests prognostic relevance for recipient HLA A2, CMV, and EBV infections or reactivations and strong initial tacrolimus-based immunosuppression. Patients with risk factors may benefit from intensified screening for PTLD.

Post-transplant lymphoproliferative disorders

Post-transplant lymphoproliferative disorders (PTLDs) are a group of conditions that involve uncontrolled proliferation of lymphoid cells as a consequence of extrinsic immunosuppression after organ or haematopoietic stem cell transplant. PTLDs show some similarities to classic lymphomas in the non-immunosuppressed general population. The oncogenic Epstein-Barr virus (EBV) is a key pathogenic driver in many early-onset cases, through multiple mechanisms. The incidence of PTLD varies with the type of transplant; a clear distinction should therefore be made between the conditions after solid organ transplant and after haematopoietic stem cell transplant. Recipient EBV seronegativity and the intensity of immunosuppression are among key risk factors. Symptoms and signs depend on the localization of the lymphoid masses. Diagnosis requires histopathology, although imaging techniques can provide additional supportive evidence. Pre-emptive intervention based on monitoring EBV levels in blood has emerged as the preferred strategy for PTLD prevention. Treatment of established disease includes reduction of immunosuppression and/or administration of rituximab (a B cell-specific antibody against CD20), chemotherapy and EBV-specific cytotoxic T cells. Despite these strategies, the mortality and morbidity remains considerable. Patient outcome is influenced by the severity of presentation, treatment-related complications and risk of allograft loss. New innovative treatment options hold promise for changing the outlook in the future.

Epstein-Barr virus-related post-transplant lymphoproliferative disorder in solid organ transplant recipients

Epstein-Barr virus (EBV) contributes to the pathogenesis of post-transplant lymphoproliferative disease (PTLD) in more than 70% of cases. EBV DNAemia surveillance has been reported to assist in the prevention and treatment of PTLD in hematopoietic stem-cell transplantation (HSCT) recipients. Derived from experience in HSCT and taking into account that PCR-based EBV monitoring techniques are currently available in most solid organ transplant (SOT) centres, there is a great interest in EBV surveillance and prevention of PTLD in SOT recipients. In the present document we have tried to address from a practical perspective different important topics regarding the prevention and management of EBV-related PTLD in SOT. To this end, available information on SOT was analysed and combined with potentially useful data from HSCT and expert observations. The document is therefore structured according to different specific questions, each of them culminating in a consensus opinion of the panel of European experts, grading the answers according to internationally recognized levels of evidence. The addressed issues were grouped under the following topics. (i) Timing and epidemiological data of PTLD. Prophylaxis guided by clinical risk factors of early and late PTLD in SOT. (ii) Relationship of EBV DNAemia load monitoring and the development of PTLD in solid organ transplant recipients. (iii) Monitoring of EBV DNAemia after SOT. Which population should be monitored? What is the optimal timing of the monitoring? (iv) Management of SOT recipients with persistent and/or increasing EBV DNAemia.