Clinical Utility of Epstein-Barr Virus Viral Load Monitoring and Risk Factors for Posttransplant Lymphoproliferative Disorders After Kidney Transplantation: A Single-Center, 10-Year Observational Cohort Study

Post-transplant lymphoproliferative disorders following kidney transplantation: A literature review with updates on risk factors, prognostic indices, screening strategies, treatment and analysis of donor type

Post-transplant lymphoproliferative disorders (PTLD) is a devastating complication of kidney transplantation with an insidious presentation and potential to disseminate aggressively. This review delineates the risk factors, prognostic indexes, screening, current management algorithm and promising treatment strategies for PTLD. Kidneys from both extended criteria donors (ECD) and living donors (LD) are being increasingly used to expand the donor pool. This review also delineates whether PTLD outcomes vary based on these donor sources. While Epstein-Barr virus (EBV) is a well-known risk factor for PTLD development, the use of T-cell depleting induction agents has been increasingly implicated in aggressive, monomorphic forms of PTLD. Research regarding maintenance therapy is sparse. The international prognostic index seems to be the most validate prognostic tool. Screening for PTLD is controversial, as annual PET-CT is most sensitive but costly, while targeted monitoring of EBV-seronegative patients was more economically feasible, is recommended by the American Society of Transplantation, but is limited to a subset of the population. Other screening strategies such as using Immunoglobulin/T-cell receptor require further validation. A risk-stratified approach is taken in the treatment of PTLD. The first step is the reduction of immunosuppressants, after which rituximab and chemotherapy may be introduced if unsuccessful. Some novel treatments have also shown potential benefit in studies: brentuximab vedotin, chimeric antigen receptor T-cell therapy and EBV-specific cytotoxic T lymphocytes. Analysis of LD v DD recipients show no significant difference in incidence and mortality of PTLD but did reveal a shortened time to development of PTLD from transplant. Analysis of SCD vs ECD recipients show a higher incidence of PTLD in the ECD group, which might be attributed to longer time on dialysis for these patients, age, and the pro-inflammatory nature of these organs. However, incidence of PTLD overall is still extremely low. Efforts should be focused on optimising recipients instead. Minimising the use of T-cell depleting therapy while encouraging research on the effect of new immunosuppressants on PTLD, screening for EBV status are essential, while enabling shared decision-making during counselling when choosing kidney donor types and individualised risk tailoring are strongly advocated.

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.

Development and Validation of a Risk Score for Post-Transplant Lymphoproliferative Disorders among Solid Organ Transplant Recipients

Post-transplant lymphoproliferative disease (PTLD) is a well-recognized complication after transplant. This study aimed to develop and validate a risk score to predict PTLD among solid organ transplant (SOT) recipients. Poisson regression identified predictors of PTLD with the best fitting model selected for the risk score. The derivation cohort consisted of 2546 SOT recipients transpanted at Rigshospitalet, Copenhagen between 2004 and 2019; 57 developed PTLD. Predictors of PTLD were high-risk pre-transplant Epstein–Barr Virus (EBV), IgG donor/recipient serostatus, and current positive plasma EBV DNA, abnormal hemoglobin and C-reactive protein levels. Individuals in the high-risk group had almost 7 times higher incidence of PTLD (incidence rate ratio (IRR) 6.75; 95% CI: 4.00–11.41) compared to the low-risk group. In the validation cohort of 1611 SOT recipients from the University Hospital of Zürich, 24 developed PTLD. A similar 7 times higher risk of PTLD was observed in the high-risk group compared to the low-risk group (IRR 7.17, 95% CI: 3.05–16.82). The discriminatory ability was also similar in derivation (Harrell’s C-statistic of 0.82 95% CI (0.76–0.88) and validation (0.82, 95% CI:0.72–0.92) cohorts. The risk score had a good discriminatory ability in both cohorts and helped to identify patients with higher risk of developing PTLD.

Increased EBV DNAemia after Anti-SARS-CoV-2 Vaccination in Solid Organ Transplants

The reactivation of latent viruses during SARS-CoV-2 infection is well recognized, and coinfection with Epstein−Barr virus (EBV) has been associated with severe clinical cases of COVID-19 infection. In transplant patients, EBV infection presents a significant challenge. Assessing the potential impact of SARS-CoV-2 vaccinations on EBV infections in stable kidney and liver transplant recipients was the objective of our study. Ten solid-organ-transplant (SOT) patients (eight kidney and two liver) vaccinated with standard doses of mRNA COVID-19 vaccines were included. EBV DNA viral load measurements were conducted prior to the vaccination and during a follow-up period (at the first month and after six months) after the second vaccine dose. After the second dose, a significant increase in median viremia was observed (p < 0.01) in 9 patients, and in one patient, the reactivation of EBV infection was found. Six months later, the median viremia decreased significantly (p < 0.05). The EBV viral load should be closely monitored as it could lead to the earlier diagnosis and treatment of EBV-related complications. Despite experiencing a decrease in the viral load six months post-vaccination, some patients still had a viral load over the baseline, which increased the risk of potential complications.

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.

Post-transplant lymphoproliferative disorder in adult renal transplant recipients: case series and review of literature

Post-transplant lymphoproliferative disorder (PTLD) is serious life-threating complication of transplantation. The clinical picture differs from lymphomas observed in the general population, with different manifestation, histopathology, higher aggressiveness with involvement of sites beyond the primary lymph node, and poorer outcome.

The objective of the study was to present nine cases of PTLD observed in our centre among the kidney transplant recipient population and discuss the results with up-to-date literature. We performed a retrospective single-centre assessment of PTLD incidence in the cohorts of kidney transplant recipients followed by our centre. We found nine cases of PTLD, five men and four woman, aged from 26 to 67 years at the time of diagnosis (mean [SD] 48 [5] years), transplanted between 1997 and 2013.

The disease was diagnosed between 2002 and 2017, from 6 to 440 months after transplantation (mean [SD] 96 [137] months). A diffuse large B-cell lymphoma was found in seven cases early as well as late after transplantation, and two patients presented T-cell lymphoma. Five patients achieved complete remission with no relapses after 6 to 13 months of treatment. In three cases the remission was achieved by switching to mammalian target of rapamycin inhibitors (mTORi) only. Four recipients died from 2 weeks to 15 months after PTLD was diagnosed.

Although the diagnostic criteria of different forms of PTLD are commonly known, rapid and correct diagnosis is not easy. PTLD is a relatively a rare disease, so there are too few studies and little consensus on the optimal treatment.

Small Bowel Perforation as the Initial Manifestation of Post-Transplant Lymphoproliferative Disorder in a Kidney and Pancreas Transplant Recipient: A Case Report

Post-transplant lymphoproliferative disorder (PTLD) comprises a broad spectrum of diseases and is a rare but serious complication of solid organ transplantation. We report the case of a 45-year-old simultaneous pancreas and kidney (SPK) transplant recipient with diffuse, early-onset PTLD, manifesting as jejunal perforation at 6 months after transplantation. The patient underwent urgent small bowel resection of the affected portion of jejunum. The surgical pathology report was significant for diffuse large B-cell lymphoma. Subsequently, the patient underwent a full workup, including upper and lower endoscopy and whole-body positron emission tomography that revealed involvement of the axial skeleton and multiple abdominal organs with sparing of the grafts. He was treated with rituximab and intrathecal methotrexate for central nervous system prophylaxis. The patient experienced complete resolution of disease by positron emission tomography 8 months after initial presentation. We found no previous report in the literature of intestinal perforation as the initial presentation of PTLD in SPK transplant recipients.

The FcγRIIIA-158 VV genotype increased the risk of post-transplant lymphoproliferative disorder in T-cell-depleted kidney transplant recipients - a retrospective study

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication in organ transplant recipients. The use of T lymphocyte-depleting antibodies (TLDAb), especially rabbit TLDAb, contributes to PTLD, and the V158F polymorphism of Fc gamma receptor IIIA (FcγRIIIA) also named CD16A could affect the concentration-effect relationship of TLDAb. We therefore investigated the association of this polymorphism with PTLD in kidney transplant recipients. We characterized the V158F polymorphism in two case-control cohorts (discovery, n = 196; validation, n = 222). Then, we evaluated the binding of rabbit IgG to human FcγRIIIA-158V and FcγRIIIA-158F. The V158F polymorphism was not linked to PTLD in the overall cohorts, but risk of PTLD was increased in VV homozygous recipients receiving TLDAb compared with F carriers in both cohorts, especially in recipients receiving TLDAb without muromonab (discovery: HR = 2.22 [1.03-4.76], P = 0.043, validation: HR = 1.75 [1.01-3.13], P = 0.049). In vitro, we found that the binding of rabbit IgG to human NK-cell FcγRIIIA was increased when cells expressed the 158-V versus the 158-F allotype. While the 158-V allotype of human FcγRIIIA binds rabbit immunoglobulin-G with higher affinity, the risk of PTLD was increased in homozygous VV kidney transplant recipients receiving polyclonal TLDAb.

Post-transplant Lymphoproliferative Disorder of Naso-orbital Region in Adult Renal Transplant Recipients: A Case Report and Literature Review

Post-transplant lymphoproliferative disorder (PTLD) is an uncommon but fatal complication following both solid organ and hematologic stem cell transplantations. Epstein-Barr virus (EBV) has been considered a main etiologic agent causing PTLD, especially in the first year after transplantation. Extranodal manifestations are frequently found in PTLD; however, naso-orbital involvement in adults is rare. We report a case of EBV-associated PTLD of the naso-orbital region in a 72-year-old patient that occurred 10 years after kidney transplant. Six additional adults with naso-orbital PTLD were identified after completing this literature review, including 2 cases with eyelid swelling, 3 cases with proptosis, and 1 case with facial numbness. The majority of cases occurred after 1 year of transplantation and were associated with EBV. This report emphasizes recognizing PTLD as differential diagnosis in transplant recipients who present with naso-orbital symptoms.