Posttransplant Lymphoproliferative Disorder Following Kidney Transplantation: A Review

Identification of non-virologic risk factors for lymphoma after the first year of kidney transplant in adults: A retrospective analysis

BACKGROUND

Non-virologic risk factors for lymphoma after the first kidney transplant (KT) year or late-onset post-transplant lymphoma (PTL) have been scarcely studied.

METHODS

This secondary study re-analyzed de-identified, non-coded data. Cause-specific Cox regressions analyzed associations between non-virologic risk factors and lymphoma or all-cause mortality among kidney transplant recipients (KTRs) with conditional cancer-free survival one year after KT.

RESULTS

Among 166,256 adult KTRs, factors with the strongest risks for late-onset PTL were recipient age > /= 65 and 50-64 years (HR = 2.38, 95 % CI = 2.25-2.77, HR = 1.77, 95 % CI= 1.58-1.79; respectively) and pretransplant cancer history (HR = 1.46, 95 % CI = 1.21-1.77). Other risk factors for late-onset PTL included alemtuzumab induction, other primary kidney disease, a prior KT, male KTR sex, expanded criteria (ECD) transplant, and acute rejection. Factors associated with a decreased risk of late-onset PTL, albeit with an increased mortality risk, included native diabetic renal disease, pre-transplant dialysis > 2 years, and steroids or proliferation signal inhibitors maintenance immunosuppressant.

CONCLUSION

Non-virologic risk factors including KTRs advanced age or male sex, prior cancer or KT, alemtuzumab induction, ECD transplant, and acute rejection are associated with PTL beyond the first post-KT year.

Real-world evidence regarding cancer, mortality, and graft failure risk with de novo belatacept use among kidney transplant recipients in the United States

Belatacept is a selective T cell costimulation blocker used in maintenance immunosuppression for kidney transplant recipients (KTRs), but evidence on cancer risk and other outcomes is limited. This retrospective cohort study used linked US transplant and cancer registry data on KTRs treated with belatacept (N = 1514) or tacrolimus (N = 7570) as initial maintenance therapy. We used multivariable Cox regression models to compare the incidence of invasive cancer, cutaneous squamous cell carcinoma, posttransplant lymphoproliferative disorder (PTLD), death, and graft failure/retransplantation (GF/RT) between belatacept and tacrolimus users. Overall, cancer incidence was 10.1 and 12.6 per 1000 person-years in belatacept and tacrolimus users, respectively. We did not find increased risk with belatacept for cancer overall (adjusted hazard ratio [HR], 0.83; 95% confidence interval [CI], 0.53-1.30), individual cancer types, or cutaneous squamous cell carcinoma. Belatacept was associated with increased risk of death (adjusted HR, 1.22; 95% CI, 1.04-1.43) but lower risk of GF/RT >4 years after transplantation (adjusted HR, 0.54; 95% CI, 0.35-0.83). PTLD risk was increased among Epstein-Barr virus-seropositive KTRs (adjusted HR, 1.96; 95% CI, 1.03-3.73). This study provides reassurance that belatacept does not increase cancer risk among KTRs, and there was a long-term protective association for GF/RT. However, we found evidence suggesting a potentially increased risk of PTLD and death with belatacept use.

The Impact of Epstein-Barr Virus Serostatus Mismatch in Adult Kidney Transplant Recipients: An Analysis of the 2012-2022 OPTN Database

BACKGROUND AND AIMS

One strategy to minimize the risk of posttransplant lymphoproliferative disorder (PTLD) is to avoid an Epstein-Barr Virus (EBV) mismatch through kidney paired donation. We aimed to estimate the incidence of PTLD in EBV-negative kidney transplant recipients with EBV-positive donors (D+/R-) and evaluate the excess risk of death following the occurrence of PTLD.

METHODS

We included adult patients in OPTN database who underwent kidney transplants between 2012 and 2022. Cox regression analysis was employed to evaluate the impact of EBV serostatus on the development of PTLD, and to assess mortality following PTLD diagnosis in D+/R- individuals.

RESULTS

A total of 179 068 patients were included, with 92.8% in the R+, 6.4% in the D+/R-, and 0.8% in the D-/R- group. D+/R- exhibited a significantly higher risk of PTLD compared to R+ and D-/R- groups. D+/R- had a greater risk of PTLD when compared to D-/R- recipients (aHR: 3.82; p < 0.001). Among D+/R- recipients, those who developed PTLD had a significantly higher risk of mortality (aHR: 2.28; p < 0.001 in deceased donor kidney transplant [DDKT] and aHR: 5.22; p < 0.001 in living donor kidney transplant [LDKT]).

CONCLUSIONS

D+/R- recipients have nearly a fourfold higher risk of PTLD compared to D-/R- recipients, suggesting that choosing an EBV D-/R- transplant could reduce the PTLD risk by about 73%. This data is crucial for counseling EBV-negative patients considering kidney paired donation to avoid an EBV serostatus mismatch.

Peritoneal lymphomatosis as a rare entity of post-transplant lymphoproliferative disorder after kidney transplantation: a case report

Post-transplant lymphoproliferative disorder (PTLD) is a severe complication of solid organ transplantation, and its manifestation as peritoneal lymphomatosis (PL) is extremely rare. This report describes the case of a 65-year-old kidney transplant recipient who presented with massive ascites as the initial symptom of PTLD 8 years post-transplantation. The patient experienced a sudden onset of ascites, and both his serum and ascitic fluid showed elevated lactate dehydrogenase (LDH) levels along with characteristic computed tomography (CT) findings, both of which raised the suspicion of lymphoma. The cytology of the ascitic fluid confirmed the diagnosis of peritoneal primary diffuse large B-cell lymphoma, leading to an early diagnosis of PL and management strategies. Although the patient developed tumor lysis syndrome soon after chemotherapy, prompt management led to complete remission. When ascites is observed in post-transplant recipients, it is essential to consider PTLD, recognize the diagnostic value of LDH levels and CT imaging, and emphasize the importance of early intervention to achieve favorable outcomes. To the best of our knowledge, this is the first reported case of PL in a kidney transplant recipient.

Kidney Disease and Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for patients with hematologic malignancies and certain solid tumors and nonmalignant hematologic conditions. Both AKI and CKD occur commonly after HSCT and are associated with significant morbidity and mortality. AKI and CKD in this setting may result from direct effects of the transplant or be caused by pretransplant bone marrow conditioning regimens and/or nephrotoxic agents administered in the post-transplant period. In this article, we review the epidemiology, risk factors, etiologies, pathophysiology, diagnosis, prevention, and treatment of post-HSCT AKI and CKD, with special attention to recent advances in this fast-moving and evolving field.

Donor-derived posttransplant lymphoproliferative disease detection by donor-derived cell-free DNA

Posttransplant lymphoproliferative disorder (PTLD) is a life-threatening complication of organ transplantation, commonly diagnosed after patients present with nonspecific constitutional symptoms and/or transplant organ dysfunction. In this article, we report a case of a kidney transplant recipient who was found to have highly elevated circulating donor-derived cell-free DNA (dd-cfDNA) levels on routine serum surveillance for allograft rejection, initially without organ dysfunction or evidence of allograft rejection on biopsy. Later, for cause imaging revealed retroperitoneal lymphadenopathy and an allograft hilar mass, which was biopsied to show PTLD/diffuse large B cell lymphoma. The elevated circulating dd-cfDNA levels in this patient prompted targeted next-generation sequencing of the same 266 single-nucleotide polymorphisms used to detect dd-cfDNA on the diffuse large B cell lymphoma, which identified it as derived from the donor. The patient achieved complete remission with retained allograft kidney function after reduced immunosuppression and 6 cycles of immunochemotherapy. This case suggests that dd-cfDNA may be an early detection tool in rare but potentially life-threatening cases of donor-derived malignancy, such as donor-derived PTLD.

The assesement of the long-term effects of kidney transplantation, including the incidence of malignant tumors, in recipients operated on between 2006 and 2015 - a cohort study and literature review

<b>Introduction:</b> Chronic kidney disease (CKD) is a global public health problem, occurring more frequently in developed countries. In Poland, it affects approximately 4 million people, which constitutes 10.8% of the population. End-stage renal disease (ESRD) requires renal replacement therapy - dialysis therapy or kidney transplantation. Kidney transplantation, supported by immunosuppressive therapy, is the preferred method of treating ESRD, improving the quality and length of life of patients.<b>Aim and Methods:</b> The aim of the study was to determine the long-term effects of kidney transplantation, including proper graft function, the frequency of adverse effects of immunosuppressive therapy, the degree of patient compliance with therapeutic recommendations, and the incidence of malignancies. A survey was conducted in a group of 137 patients who underwent kidney transplantation between 2006 and 2015. Hospitalization data were also analyzed, including age, body weight and blood type of the recipient.<b>Results:</b> Of the 137 patients studied, 61 were women and 76 were men. The mean age of the patients was 45.1 years. The most common etiology of CKD was glomerulonephritis. After kidney transplantation, 86.86% of patients declared normal graft function. Post-transplant weight gain was noted in 75.18% of patients. 11.68% of recipients developed malignancies, with an average time from transplantation to diagnosis of 5.1 years. Of the patients with cancer, 93.75% maintained normal graft function.<b>Conclusions:</b> Long-term effects of kidney transplantation are satisfactory, with a high percentage of patients maintaining normal graft function. Complications associated with immunosuppressive therapy are comparable to literature data. It is necessary to increase patient awareness of modifiable risk factors to improve treatment outcomes. The incidence of malignancy after transplantation is lower than in the literature, but the methodological limitations of the study must be taken into account. Cancer treatment had no significant effect on graft function in most cases.

Impact of antiviral prophylaxis on EBV viremia and posttransplant lymphoproliferative disorders in solid organ transplant recipients: a systematic review and meta-analysis

INTRODUCTION

Organ transplant recipients face a substantial risk of developing posttransplant lymphoproliferative disorders (PTLD). In over 90% of cases with B-cell PTLD following solid organ transplantation, the Epstein-Barr virus (EBV) genome is promptly identified, usually within the initial year. A continuing discussion revolves around the efficacy of antiviral prophylaxis in mitigating the incidence of PTLD in solid organ transplant (SOT) patients. This study aimed to conduct a systematic review and meta-analysis to investigate this issue.

METHOD

A comprehensive search was conducted up to December 31, 2023, in databases including PubMed, Embase, and the Cochrane Library for retrospective and prospective studies comparing antiviral prophylaxis effects on EVB viremia and PTLD incidence in SOT recipients. Fixed or random effect models were applied based on the heterogeneity assessed via the I2 statistic, using Stata 16.0 software for data analysis.

RESULTS

In total, 22 eligible studies involving 13,498 patients were analyzed. Antiviral prophylaxis was associated with a significant reduction in EBV viremia incidence in SOT recipients, as demonstrated in 10 studies (relative risk (RR) 0.69, 95% CI 0.54 to 0.88). The rate of PTLD was significantly lower among those who received antiviral prophylaxis compared to those who did not, as reported in 18 studies (RR 0.77, 95% CI 0.63 to 0.94). No significant difference was observed in the subgroup of high-risk recipients based on EBV serology (RR 1.13, 95% CI 0.72 to 1.78). Additionally, a notable reduction in PTLD incidence was seen in the pediatric subgroup (RR 0.58, 95% CI 0.43 to 0.79) using antiviral prophylaxis, while no significant differences were observed in the subgroup of adults (RR 0.88, 95% CI 0.64 to 1.21). Administration of antiviral prophylaxis can significantly reduce the incidence of PTLD among kidney (RR 0.63, 95% CI 0.46 to 0.87) and heart transplant patients (RR 0.61, 95% CI 0.39 to 0.96). PTLD incidence was significantly reduced among recipients of T-cell depletion or steroid-based immunosuppression using antiviral prophylaxis (RR 0.54, 95% CI 0.39-0.74 and RR 0.55, 95% CI 0.41-0.73, respectively).

CONCLUSION

This meta-analysis revealed that administering antiviral prophylaxis to patients after solid organ transplantation reduces PTLD and EBV viremia occurrences, especially among pediatric recipients, individuals undergoing kidney or heart transplantation, and those receiving high-intensity immunosuppression regimens. Post-transplant lymphoproliferative disorders (PTLD) and other EBV syndromes are among the most serious complications following solid organ transplantation (SOT), primarily due to the necessity for prolonged immunosuppressive therapy. Among the strategies for preventing EBV-related complications, the use of antiviral prophylaxis is a subject of ongoing debate. This systematic review and meta-analysis found that antiviral prophylaxis significantly reduced EBV viremia incidence (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.54 to 0.88) compared to those without prophylaxis. In the sub-analysis related to high-risk EBV serologically mismatched SOT recipients (EBV D+/R-), the result did not show a significant difference in terms of PTLD incidence (RR 1.13, 95% CI 0.72 to 1.78). Antiviral prophylaxis significantly impacted the occurrence of PTLD events among pediatric SOT patients (RR 0.58, 95% CI 0.43 to 0.79), but not among adult patients (RR 0.88, 95% CI 0.64 to 1.21). Antiviral prophylaxis significantly impacted the occurrence of PTLD events among kidney/simultaneous pancreas and kidney (RR 0.63, 95% CI 0.46 to 0.87) and heart (RR 0.61, 95% CI 0.39 to 0.96) transplant patients but not liver  (RR 0.5, 95% CI 0.23 to 1.08) transplant recipients.

Targeted gene therapy for rare genetic kidney diseases

Chronic kidney disease is one of the leading causes of mortality worldwide because of kidney failure and the associated challenges of its treatment including dialysis and kidney transplantation. About one-third of chronic kidney disease cases are linked to inherited monogenic factors, making them suitable for potential gene therapy interventions. However, the intricate anatomical structure of the kidney poses a challenge, limiting the effectiveness of targeted gene delivery to the renal system. In this review, we explore the progress made in the field of targeted gene therapy approaches and their implications for rare genetic kidney disorders, examining preclinical studies and prospects for clinical application. In vivo gene therapy is most commonly used for kidney-targeted gene delivery and involves administering viral and nonviral vectors through various routes such as systemic, renal vein, and renal arterial injections. Small nucleic acids have also been used in preclinical and clinical studies for treating certain kidney disorders. Unexpectedly, hematopoietic stem and progenitor cells have been used as an ex vivo gene therapy vehicle for kidney gene delivery, highlighting their ability to differentiate into macrophages within the kidney, forming tunneling nanotubes that can deliver genetic material and organelles to adjacent kidney cells, even across the basement membrane to target the proximal tubular cells. As gene therapy technologies continue to advance and our understanding of kidney biology deepens, there is hope for patients with genetic kidney disorders to eventually avoid kidney transplantation.

Accurate Multiplex qPCR Detection of Epstein-Barr Virus/Cytomegalovirus/BK Virus in Kidney Transplant Patients: Pilot Study

Chronic kidney disease is a really important heath issue, and transplantation is an intervention that can greatly increase patient quality of life and survival. The aim of this study was to perform a comprehensive evaluation of the BK virus, CMV, and EBV in kidney transplant recipients (KTRs); to assess the prevalence of infections; and to test if our detection method would be feasible for use in follow-ups with KTRs. A total of 157 KTRs registered at the Clinical Hospital "Dr. C. I. Parhon", Iași, Romania, were selected using specific inclusion/exclusion criteria. We tested the blood samples from each patient for BK, EBV, and CMV using a multiplex real-time PCR (qPCR) assay and the TaqMan PCR principle. The highest prevalence was detected for BKV (11/157, 7%), followed by CMV (9/157, 5.7%) and EBV (5/157, 3.2%). By simultaneously detecting three possible nephropathic viruses and oncogenes in KTRs using multiplex real-time PCR, we aimed to optimize their monitoring and follow-up. The prevalence of the tested nephropathogenic viruses-BKV, CMV, and EBV-was comparable to that analyzed in other studies. We demonstrate that the use of qPCR for viral detection in KTRs is a robust, cost-effective method for case monitoring.

[A case of primary central nervous system post-transplant lymphoproliferative disease 14 years after living donor liver transplantation]

The patient was a 51-year-old man who had undergone living donor liver transplantation for type B cirrhosis at the age of 37 years, and had a history of immunosuppressive drug use. He had developed focal seizures starting from his right upper limb, and MRI showed a lesion in the subcortical white matter of his left parietal lobe. Sensory disturbance and paralysis progressed in his right upper and lower limbs, and his brain lesion rapidly enlarged. A brain biopsy revealed diffuse large B-cell lymphoma, and Epstein-Barr virus-encoded small RNA in situ hybridization was positive. The patient was diagnosed with primary central nervous system post-transplant lymphoproliferative disorder (PCNS-PTLD) with no lesions in other organs. There are few reports of PCNS-PTLD cases after living donor liver transplantation in Japan. Although rare, it is nevertheless important to consider this disease in patients receiving immunosuppressive drugs after organ transplantation who develop brain lesions, regardless of which organ was transplanted.

Cancer Screening and Cancer Treatment in Kidney Transplant Recipients

As the population ages and post-transplant survival improves, pretransplant and post-transplant malignancy are becoming increasingly common. In addition, rapid advances in cancer therapies and improving outcomes prompt us to rethink pretransplant cancer-free wait time and screening strategies. Although kidney transplant recipients (KTRs) are at higher risk of developing cancer, epidemiological data on how to best screen and treat cancers in KTRs are incomplete. Thus, current recommendations are still largely on the basis of studies in the general population, and their validity in KTRs is uncertain. Kidney transplant candidates without prior cancer should be evaluated for latent malignancies even in the absence of symptoms. Conversely, individuals with a history of malignancy require thorough monitoring to detect potential recurrences or de novo malignancies. When treating KTRs with cancer, reducing immunosuppression can enhance antitumor immunity, yet this also increases the risk of graft rejection. Optimal treatment and immunosuppression management remains undefined. As the emergence of novel cancer therapies adds complexity to this challenge, individualized risk-benefit assessment is crucial. In this review, we discuss up-to-date data on pretransplant screening and cancer-free wait time, as well as post-transplant cancer screening, prevention strategies, and treatment, including novel therapies such as immune checkpoint inhibitors and chimeric antigen receptor T-cell therapies.

Primary cutaneous EBV+ extranodal NK/T-cell lymphoma of gamma/delta T-cell lineage in the posttransplantation setting

Posttransplantation primary cutaneous T-cell lymphomas (PT-CTCL) are a rare complication of sustained immunosuppression in the posttransplant setting. When present, PT-CTCLs are typically EBV- and exhibit features of mycosis fungoides/Sézary syndrome or CD30+ lymphoproliferative disorders. We present a case of a 75-year-old individual who developed skin lesions 30 years after liver transplantation. Pathologic evaluation of the skin biopsy revealed involvement by a clonal, EBV+ T-cell population of gamma/delta lineage with no evidence of systemic disease. Comprehensive genomic profiling was performed, confirming focal one-copy loss of 6q23.3, altogether consistent with the extremely rare and unusual diagnosis of primary cutaneous EBV+ extranodal NK/T-cell lymphoma of gamma/delta T-cell lineage in the posttransplantation setting.

The impact of induction therapy on the risk of posttransplant lymphoproliferative disorder in adult kidney transplant recipients with donor-recipient serological Epstein-Barr virus mismatch

Posttransplant lymphoproliferative disorder (PTLD) poses a significant concern in Epstein-Barr virus (EBV)-negative patients transplanted from EBV-positive donors (EBV R-/D+). Previous studies investigating the association between different induction agents and PTLD in these patients have yielded conflicting results. Using the Organ Procurement and Transplant Network database, we identified EBV R-/D+ patients >18 years of age who underwent kidney-alone transplants between 2016 and 2022 and compared the risk of PTLD with rabbit antithymocyte globulin (ATG), basiliximab, and alemtuzumab inductions. Among the 6620 patients included, 64.0% received ATG, 23.4% received basiliximab, and 12.6% received alemtuzumab. The overall incidence of PTLD was 2.5% over a median follow-up period of 2.9 years. Multivariable analysis demonstrated that the risk of PTLD was significantly higher with ATG and alemtuzumab compared with basiliximab (adjusted subdistribution hazard ratio [aSHR] = 1.98, 95% confidence interval [CI] 1.29-3.04, P = .002 for ATG and aSHR = 1.80, 95% CI 1.04-3.11, P = .04 for alemtuzumab). However, PTLD risk was comparable between ATG and alemtuzumab inductions (aSHR = 1.13, 95% CI 0.72-1.77, P = .61). Therefore, the risk of PTLD must be taken into consideration when selecting the most appropriate induction therapy for this patient population.

Posttransplant Lymphoproliferative Disease Following Pancreas Transplantation: A 40 Year Single-Center Experience

BACKGROUND

Chronic immunosuppression following pancreas transplantation carries significant risk, including posttransplant lymphoproliferative disease (PTLD). We sought to define the incidence, risk factors, and long-term outcomes of PTLD following pancreas transplantation at a single center.

METHODS

All adult pancreas transplants between February 1, 1983 and December 31, 2023 at the University of Minnesota were reviewed, including pancreas transplant alone (PTA), simultaneous pancreas-kidney transplants (SPK), and pancreas after kidney transplants (PAK).

RESULTS

Among 2353 transplants, 110 cases of PTLD were identified, with an overall incidence of 4.8%. 17.3% were diagnosed within 1 year of transplant, 32.7% were diagnosed within 5 years, and 74 (67.3%) were diagnosed after 5 years. The overall 30-year incidence of PTLD did not differ by transplant type-7.4% for PTA, 14.2% for SPK, and 19.4% for PAK (p = 0.3). In multivariable analyses, older age and Epstein-Barr virus seronegativity were risk factors for PTLD, and PTLD was a risk factor for patient death. PTLD-specific mortality was 32.7%, although recipients with PTLD had similar median posttransplant survival compared to those without PTLD (14.9 year vs. 15.6 year, p = 0.9).

CONCLUSIONS

PTLD following pancreas transplantation is associated with significant mortality. Although the incidence of PTLD has decreased over time, a high index of suspicion for PTLD following PTx should remain in EBV-negative recipients.

Interactions of TTV with BKV, CMV, EBV, and HHV-6A and their impact on post-transplant graft function in kidney transplant recipients

Background

Mono and combined reactivation of latent viruses occurs frequently under immunosuppressive therapy in kidney transplant patients. Recently, monitoring torque teno virus (TTV) reactivation came more into focus as a potential biomarker for immune status. The surrogate characteristics of TTV reactivation on acute rejection, and the combined reactivation with other latent viruses such as cytomegalovirus (CMV), human BK virus (BKV), Epstein-Barr virus (EBV), and human herpes virus-6A (HHV-6A) on allograft function, are unknown so far.

Methods

Blood samples from 93 kidney transplant recipients obtained during the first post-transplant year were analyzed for TTV/BKV/CMV/EBV/HHV-6A load. Clinical characteristics, including graft function [glomerular filtration rate (GFR)], were collected in parallel.

Results

TTV had the highest prevalence and viral loads at 100% and a mean of 5.72 copies/ml (cp/ml) (log10). We found 28.0%, 26.9%, 7.5%, and 51.6% of simultaneous reactivation of TTV with BKV, CMV, EBV, and HHV-6, respectively. These combined reactivations were not associated with a significantly reduced estimated GFR at month 12. Of interest, patients with lower TTV loads <5.0 cp/ml (log10) demonstrated not only a higher incidence of acute rejection, but also an unexpected significantly earlier occurrence and higher incidence of BKV and HHV-6A reactivation. Correlations between TTV loads, other latent viruses, and immunosuppressive medication were only significant from 6 months after transplant.

Conclusion

We were able to observe and support previously introduced TTV load thresholds predicting kidney allograft rejection. However, due to a possible delayed relation between immunosuppressive medication and TTV viral load adaptation, the right time points to start using TTV as a biomarker might need to be further clarified by other and better designed studies.

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.

Non-Hodgkin lymphoma in a kidney transplanted patient with methylmalonic acidemia: Metabolic susceptibility and the role of immunosuppression

Methylmalonic acidemia cblB type (MMA cblB) is an autosomal recessive inborn error of amino acid metabolism that results in impaired synthesis of adenosylcobalamin, a cofactor of methylmalonyl-CoA mutase. It presents with episodes of coma, vomiting, hypotonia, metabolic acidosis, and hyperammonemia. End-stage kidney disease is a long-term complication. Treatments include vitamin B12 supplementation, L-carnitine, and a low-protein diet. Liver, kidney, or combined liver-kidney transplantations are promising options, but they are not without complications. We report a patient suffering from MMA cblB who developed end-stage kidney disease at 18 years of age. Kidney transplantation allowed him to recover normal kidney function and good metabolic control. Unfortunately, after two decades, he developed non-Hodgkin lymphoma and severe chemotherapy toxicity which led to his death. The risk of lymphoproliferative diseases is known to increase after solid organ transplantation. However, in MMA, factors including mitochondrial dysfunction and oncometabolites, may further increase the risk of malignancy and drug toxicity. Our report highlights the importance of considering the increased risk of cancer in long-term follow-up of MMA cblB patients, especially after solid organ transplantation. Moreover, when chemotherapy is needed, the increased risk of toxicity and metabolic decompensation should be considered and monitored.

Temporal Trends, Risk Factors, and Clinical Outcomes of De Novo Lymphoproliferative Disorders After Heart Transplantation

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) is an important cause of morbidity and mortality in heart transplant (HTx) recipients. However, previous studies of PTLD after HTx are limited to single-center analyses or extrapolated from all solid organ transplantations.

OBJECTIVES

The authors analyzed the temporal trends, risk factors, and clinical outcome of de novo PTLD specifically after HTx.

METHODS

Using multi-institutional, multinational data from the International Society for Heart and Lung Transplantation Thoracic Organ Transplant Registry, the authors evaluated the real-world data of PTLD after HTx, transplanted between January 2000 and June 2015. Multivariable analysis was done to identify risk factors for PTLD development after HTx.

RESULTS

Among 28,136 HTx recipients, 1,069 (3.8%) developed PTLD within 10 years of transplantation. PTLD showed a bimodal age pattern with peak incidence in patients of pediatric age and late adulthood at transplantation. The early transplant era (2000-2007 vs 2008-2015), male recipient, and EBV donor-positive-recipient-negative match were independent risk factors of PTLD development within 3 years of transplantation, whereas maintenance therapy with cyclosporine vs tacrolimus at initial discharge was associated with a lower incidence. PTLD development within 3 years of transplantation was significantly associated with mortality (HR: 2.42 [95% CI: 2.01-2.91]; P < 0.001). Survival after PTLD diagnosis was higher in the recent transplant era.

CONCLUSIONS

PTLD is relatively rare, but potentially fatal, post-transplant malignancy. PTLD incidence and mortality after HTx have decreased in the recent era. Strategies to minimize the risk of PTLD, and ensure early diagnosis and effective treatment are likely to improve outcomes in HTx.

Pediatric Kidney Transplantation: Cancer and Cancer Risk

Children with end-stage kidney disease (ESKD) face a lifetime of complex medical care, alternating between maintenance chronic dialysis and kidney transplantation. Kidney transplantation has emerged as the optimal treatment of ESKD for children and provides important quality of life and survival advantages. Although transplantation is the preferred therapy, lifetime exposure to immunosuppression among children with ESKD is associated with increased morbidity, including an increased risk of cancer. Following pediatric kidney transplantation, cancer events occurring during childhood or young adulthood can be divided into two broad categories: post-transplant lymphoproliferative disorders and non-lymphoproliferative solid tumors. This review provides an overview of cancer incidence, types, outcomes, and preventive strategies in this population.

Demographic and Clinical Characteristics of Kidney Donors at First Check: A Single-Center Experience

OBJECTIVES

Kidney transplant is the best treatment for patients with end-stage kidney disease. In many regions of the world, including the Middle East, most kidney transplants are from living donors. In contrast to recipients, data for living donors remain scarce. Here, we describe living donor baseline characteristics at first hospital check at a single center in Baghdad, Iraq.

MATERIALS AND METHODS

We collected and analyzed demographic, laboratory, imaging, and histocompatibility data from donor records at the Nephrology and Renal Transplantation Center, Medical City-Baghdad, Baghdad, Iraq, from July 2022 to September 2022.

RESULTS

We included 124 kidney donors (56.4% male) who donated their kidneys 1 to 3 years previous to our study, with a mean age of 34.84 ± 10.04 years and mean body mass index (weight in kilograms divided by height in meters squared) of 27.11 ± 2.12. Most donors donated their kidneys to a firstdegree relative (69.2%); blood group O was the most prevalent (47.5%). More than half of the donors were unemployed. Histocompatibility testing showed that 40% of the donors had >3 human leukocyte antigen mismatches with their recipients, and 30% of the recipients were high-risk sensitized patients with a calculated panel reactive antibody >50%. Regarding the virus status, 68.5% of the donors tested positive for cytomegalovirus immunoglobulin G, 8% of the transplants were high-risk cytomegalovirus status, and 43.5% tested positive for Epstein-Barr virus immunoglobulin G. Renal imaging showed that 75.8% of donors had a single artery and 24.1% had a double artery (26.6% double left, 40% double right, and 33.3% both).

CONCLUSIONS

For living transplant procedures at a single center in Iraq, most were from related donors. Most donors are unemployed, which mandates future health and social support. High immunological and viral risks must not be ignored in a single center with living related donors.

Incidence and Features of Lymphoid Proliferation and Lymphomas after Solid Organ or Hematopoietic Stem Cell Transplantation in a National Database Cohort

PURPOSE

Post-transplantation lymphoproliferative disorders (PTLDs) after hematopoietic stem transplantation (HCT) or solid organ transplantation (SOT) result in poorer outcomes, including death. There are limited large cohort data on the incidence and natural course of PTLD in Asians.

MATERIALS AND METHODS

We investigated PTLD using Korean national health insurance claims data of 47,518 patients who underwent HCT or SOT in 2008-2020. Patient demographics, time and type of PTLD diagnosis, type of PTLD treatment, and death data were collected. We used Fine and Gray subdistribution hazard models to calculate the cumulative incidence and risk factors for PTLD.

RESULTS

During median follow-up of 5.32 years, PTLD occurred in 294 of 36,945 SOT patients (0.79%) and 235 of 10,573 HCT patients (2.22%). Cumulative incidence of PTLD were 0.49% at 1 year, 1.02% at 5 years, and 1.50% at 10 years post-transplantation. Age < 20 years (subdistribution hazard ratio [SHR] of 1.67 in age 10-19, SHR 1.51 in age 0-9), HCT (SHR 3.02), heart transplantation (SHR 2.27), and liver transplantation (SHR 1.47) were significant risk factors for PTLD. The presence of PTLD was associated with an increased risk of death (hazard ratio of 2.84). Overall, 5-year survival of PTLD patients was 68.9% (95% confidence interval, 64.9 to 73.2).

CONCLUSION

We observed a steady increase in PTLD over 10 years after HCT or SOT in this large cohort study. Pediatric age group, HCT, liver transplantation, and heart transplantation were suggested to be risk factors for PTLD, and PTLD was associated with a higher risk of death.

T cell posttransplant lymphoproliferative disorder after kidney transplantation progressing to acute liver failure: a case report

Posttransplant lymphoproliferative disorder (PTLD) is a rare and serious complication of kidney transplantation (KT), with 85% of cases being of B cell lineage. We present a case of T cell PTLD (T-PTLD) that rapidly progressed to liver failure, septic shock, and death despite various therapeutic interventions. A 50-year-old woman underwent ABO- and human leukocyte antigen-compatible preemptive living donor KT for diabetic endstage kidney disease under basiliximab induction therapy. During routine monitoring, 2 months after KT, her Epstein-Barr (EB) viral load was found to be elevated to 318,443 copies/mL. Despite a reduction in maintenance immunosuppressants and preemptive rituximab treatment, the EB viremia continued to increase. Eight months after KT, abdominopelvic computed tomography revealed multifocal splenic lesions and nonspecific lymph node enlargement. Concurrently, the patient's liver function tests began to deteriorate without evidence of viral hepatitis infection. A liver biopsy confirmed the diagnosis of EB virus-associated T-PTLD with CD3 and CD56 expression. Only 2 months after the PTLD diagnosis, the patient developed acute and severe liver failure. She died 12 days after being hospitalized, despite the administration of rescue cytotoxic chemotherapy. This case exemplifies the challenges of managing refractory EB virus-associated T-PTLD after KT, for which no specific treatment options are currently available. Further research into preventative and therapeutic methods for T-PTLD is warranted.

Cutaneous T-Cell Lymphoma (CTCL) Arising Post Kidney Transplant: A Review of Clinical Variants in the Literature

Post-transplant lymphoproliferative disease is a rare disorder with an annual incidence of 0.5% to 3.7%. Development of this disorder carries with it a poor prognosis. In this report, we describe a rare case of post-transplant primary cutaneous T-cell lymphoma (PT-CTCL) mycosis fungoides stage IIB in a patient following kidney transplantation, as well as a review of PT-CTCL reported in the literature. The treatment following diagnosis included bexarotene, cyclosporine, and prednisone. Currently, the patient is free from disease. This information aims to add to the knowledge of the prevalence and management of PT-CTCL.

EBV Reactivation in Transplant Recipients following SARS-CoV-2 Infection: A Retrospective Study

Reactivation and primary infection with a high Epstein Barr Virus (EBV) DNA level in kidney transplant patients could cause severe complications, including the development of Post-Transplantation Lymphoproliferative Disease (PTLD). While in the general population the reactivation of EBV after SARS-CoV-2 infection has been reported, very few data are available in transplant recipients. Our retrospective study aimed to evaluate a possible EBV reactivation in kidney transplant patients following SARS-CoV-2 infection and a possible impairment of the immune system. In addition, the effects of changes in immunosuppressive therapy on EBV DNA reactivation and vaccination were also evaluated. A total of 166 kidney transplant patients followed at the Kidney-Pancreas Transplant Ambulatory Nephrology Unit at Padova University Hospital were retrospectively considered for an observation period of 6 months from January 2020 to April 2023. EBV DNA level was measured by Rt-PCR and evaluated 6 months before and after SARS-CoV-2 infection. Patients' serological states were established via quantification of anti-VCA and anti-EBNA (chemiluminescence). Patients' immune systems were characterized by CD4+/CD8+ lymphocyte ratio (flow cytometry). EBV DNA was reactivated in 50% of the 166 patients with COVID-19 who completed the study. Older patients with more severe forms of COVID-19 had higher EBV reactivation (p < 0.05). EBV reactivation significantly increased in patients with severe SARS-CoV-2 infection requiring hospitalization compared to patients managed at home (p < 0.001). CD4+/CD8+ lymphocyte ratio was reduced in patients with a younger age of transplant (p < 0.01) and on a higher dose of steroids (p < 0.01). The results of our study confirm the role of immunodepression, especially in recent transplant patients and those on high steroids, in EBV reactivation. These results combined with the few available in the literature might contribute to providing an optimal management of immunosuppressive treatment for these patients in order to obtain an immune state unfavorable to the activation of latent viruses, including EBV.

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.

Histiocytic sarcoma in renal transplant patients: a literature review

BACKGROUND

Histiocytic sarcoma (HS) is defined as neoplasm resembling morphological and immunophenotypic characteristics of mature histiocytes. It is a rare form of lymphoid neoplasms. Despite advances in treatment and diagnosis of histiocytic sarcoma, majority of cases had poor prognosis due to progressive nature of the disease. In the following article, all reported cases of histiocytic sarcoma in renal transplant patients are reviewed.

METHODS

In our literature review, all relevant reports were collected electronically by entering the necessary keywords. A Boolean approach using Medical Subject Heading (MeSH) keywords was implemented. After establishing the inclusion/exclusion criteria, article titles and abstracts were evaluated by Systematic Reviews and Meta-Analyses (PRISMA) standards for 2020. All cases of histiocytic sarcoma in renal transplant patients were included.

RESULT

Based on our inclusion and exclusion criteria 4 case reports were yielded in this review. Two were males and 2 were females with the mean age of 42.25 years. Fever was the most common symptom. Although tumor originated from the native kidney on one patient, the site of the primary tumor was thorax, oropharynx, and transplanted kidney in the rest. Metastasis was detected in all cases. Prednisone was used for all cases. EBV was positive in 2 cases and negative in one of them. Histology was diagnostic and similar in all cases. Immunohistochemistry was done for 3 cases. Although chemotherapy was done for 3 patients, all 4 cases ended in mortality.

CONCLUSION

Despite the fact that neoplasms are post renal transplant complications, histiocytic sarcoma is a scarce and fatal entity in such patients. Histological and immunohistochemistry tests are the corner stone in diagnosis of histiocytic sarcoma.

A case of post renal transplant PTLD of lung

Post Transplant Lymphoproliferative Disorder (PTLD) is a heterogeneous group of Lymphoid proliferative disorders that occur in patients post Hematogenous or Solid organ transplants. They are closely associated with Ebstein-Barr Virus and can range from polyclonal lesions to frank lymphomas. PTLD is usually a rare post-transplant complication, with the incidence being higher post Lung or Heart Transplantation and less commonly seen post-renal transplantation. The incidence post renal transplantation is less than 1%, with most of the cases being limited to the Gastro-Intestinal Tract and Lymph nodes, and incidence in the lungs being extremely rare. Here we present a case report of PTLD of the lung in a post-renal transplant recipient.

Current Perspectives on the Management of Herpesvirus Infections in Solid Organ Transplant Recipients

Solid organ transplant recipients (SOTRs) are at high risk of human herpesvirus (HHV)-related morbidity and mortality due to the use of immunosuppressive therapy. We aim to increase awareness and understanding of HHV disease burden in SOTRs by providing an overview of current prevention and management strategies as described in the literature and guidelines. We discuss challenges in both prevention and treatment as well as future perspectives.

Pathological Approach to Kidney Allograft Infection

Infectious agents can pose a significant challenge in kidney transplantation, as they have the potential to cause direct infections in the transplanted kidney. These infections can lead to a decline in kidney function and reduce the longevity of the transplanted kidney. Common post-transplant allograft infections include bacterial pyelonephritis and the BK virus infection, while adenovirus, JC virus, and cytomegalovirus are less frequent but can also lead to significant allograft dysfunctions. The histopathological features of these infections are characterized by the infiltration of inflammatory cells in the kidney interstitial area and the presence of viral nuclear inclusions or cytopathic changes in the renal tubular epithelial cells. The confirmation of causative organisms can be achieved by immunohistochemical staining or the visualization of viral particles using electron microscopic examination. However, these methods typically require a longer turnaround time and are not readily available in developing countries, unlike standard hematoxylin-eosin staining. Notably, the differential diagnosis of interstitial inflammation in kidney allografts almost always includes T cell-mediated rejection, which has a different treatment approach than allograft infections. The aim of this review was to prompt clinicians to identify diverse pathological alterations as observed in kidney allograft biopsies, thereby facilitating further investigations and the management of suspected kidney allograft infections.

Post-Transplant Lymphoproliferative Disorder, Monomorphic Type, in a Kidney Transplant Patient After Administration of Anti-Influenza Vaccine

ABSTRACT

Post-transplant lymphoproliferative disorders (PTLD) are rare complications in solid organ transplant patients. Their pathogenesis is largely unknown and closely linked to low immunity, which allows uncontrolled lymphocyte proliferation. Although transplant patients receive annual influenza vaccination as a preventive protocol, we have not found any cases where the flu vaccine triggered a PTLD. We present the case of a 49-year-old female kidney transplant recipient who developed an Epstein-Barr virus-negative PTLD, CD30+ anaplastic monomorphic type, ALK-, which presented the day after a single dose of anti-influenza vaccine. The initial clinical presentation was subcutaneous, but imaging studies revealed multiorgan involvement.

Pre-Existing Intrarenal Parvovirus B19 Infection May Relate to Antibody-Mediated Rejection in Pediatric Kidney Transplant Patients

Viral infections can lead to transplant dysfunction, and their possible role in rejection is described. In total, 218 protocol biopsies performed in 106 children at 6, 12 and 24 months after transplantation were analyzed according to Banff '15. RT-PCR for cytomegalovirus, Epstein-Barr virus, BK virus and Parvovirus B19 was performed on blood and bioptic samples at the time of transplant and each protocol biopsy. The prevalence of intrarenal viral infection increases between 6 and 12 months after transplantation (24% vs. 44%, p = 0.007). Intrarenal Parvovirus B19 infection is also associated with antibody-mediated rejection (ABMR) (50% ABMR vs. 19% T-cell-mediated rejection, p = 0.04). Moreover, Parvovirus infection is higher at 12 months of follow-up and it decreases at 48 months (40.4% vs. 14%, p = 0.02), while in 24% of grafts, Parvovirus is already detectable at the moment of transplantation. Intrarenal Parvovirus B19 infection seems to be related to ABMR in pediatric kidney recipients. The graft itself may be the way of transmission for Parvovirus, so performance of a PCR test for Parvovirus B19 should be considered to identify high-risk patients. Intrarenal Parvovirus infection presents mainly during the first-year post-transplantation; thus, we recommend an active surveillance of donor-specific antibodies (DSA) in patients with intrarenal Parvovirus B19 infection during this period. Indeed, it should be considered a treatment with intravenous immunoglobulins in patients with intrarenal Parvovirus B19 infection and DSA positivity, even in the absence of ABMR criteria for kidney biopsy.

Tuberculosis combined with Burkitt lymphoma in a kidney transplant recipient: A case report and literature review

RATIONALE

Tuberculosis (TB) and post-transplant lymphoproliferative disorder are serious complications affecting the long-term survival of kidney transplant recipients (KTRs). Both of complications have overlapping clinical symptoms, signs, and high similar imaging presentation, which make early clinical diagnosis challenging. In this paper, we reported a rare case of post-transplant pulmonary TB combined with Burkitt lymphoma (BL) in KTR.

PATIENT CONCERNS

A 20-year-old female KTR presented to our hospital with abdominal pain and multiple nodules throughout the body.

DIAGNOSES

TB is diagnosed based on the lung histopathology showed fibrous connective tissue hyperplasia with number of chronic inflammatory changes, localized necrosis, granuloma formation and multinucleated giant cells were seen in the lung tissue. Moreover, lung histopathology specimen tested positive for TB gene. TB The culture for tuberculosis was positive. BL was diagnosed as metastatic after completion of liver and bone marrow biopsy.

INTERVENTIONS

After an early diagnosis of TB, the patient received intensification of anti-tubercular therapy. Because the patient was diagnosed with BL, rituximab, cardioprotection, hepatoprotection and alkalinization of urine were added.

OUTCOMES

After an early diagnosis of TB, the patient received anti-tubercular therapy and her clinical symptoms and imaging manifestations improved. After the diagnosis of BL was made, the patient's condition progressed rapidly, followed by multi-organ damage and died 3 months later.

LESSONS

Therefore, in organ transplant patients, who present with multiple nodules and normal tumor markers, they should be alerted to the possibility of concurrent TB and post-transplant lymphoproliferative disorder, and perfect tests such as Epstein-Barr virus, β2-microglobulin, lactate dehydrogenase, γ-interferon release test and Xpert Mycobacterium TB/rifampicin test and perform early lesion site biopsy to clarify the diagnosis with a view to improving the prognosis.

A Case Report of a Kidney Transplant Recipient With Organizing Pneumonia After Graft Loss

We present a case of a 68-year-old male patient who underwent ABO-incompatible living kidney transplantation from his wife because of immunoglobulin A nephropathy 13 years ago. Over time, the patient showed a gradual decline in graft function and required reinitiation of hemodialysis because of fluid overload, which led to his admission to our hospital. An arteriovenous fistula was created, and subsequently, hemodialysis therapy was started. Because he had chronic cytomegalovirus retinopathy and thrombotic microangiopathy due to immunosuppressive therapy at admission, mycophenolate mofetil and tacrolimus were discontinued during hemodialysis initiation. Only low-dose prednisolone was continued. One week later, the patient had a fever, and chest computed tomography revealed bilateral pneumonia, which was not improved by antibiotics. The patient was diagnosed with organized pneumonia. After ruling out opportunistic infection, including pneumocystis pneumonia, increased doses of prednisolone resulted in the remission of organizing pneumonia.

Short-term decreased post transplant lymphoproliferative disorder risk after kidney transplantation using two novel regimens

BACKGROUND

Belatacept is employed alongside calcineurin inhibitor (CNI) therapy to prevent graft rejection in kidney transplant patients who are Epstein-Barr virus (EBV) seropositive. Preliminary data suggested that rates of post-transplant lymphoproliferative disorder (PTLD) were higher in individuals treated with belatacept compared to CNI therapy alone.

METHODS

The records of 354 adults who underwent kidney only transplantation from January 2015 through September 2021 at one medical center were evaluated. Patients underwent treatment with either low-doses of mycophenolate, tacrolimus and sirolimus (B⁰, n = 235) or low-doses of mycophenolate, tacrolimus and belatacept (B¹, n = 119). All recipients underwent induction with antithymocyte globulin and a rapid glucocorticosteroid taper. Relevant donor and recipient information were analyzed and endpoints of PTLD were assessed.

RESULTS

There were no cases of PTLD in either cohort within the study period. Recipients in the belatacept cohort experienced lower estimated glomerular filtration rates at 12 months (B⁰: 67.48 vs. B¹: 59.10, p = 0.0014). Graft failure at 12 (B⁰: 1.28% vs. B¹: 0.84%, p = 1.0) and 24 months (B⁰:2.55% vs. B¹: 0.84%, p = 0.431) were similar. There was no difference in rejection rates at 12 (B⁰: 1.27% vs. B¹: 2.52%, p = 0.408) or 24 months (B⁰: 2.12% vs. B¹: 2.52%, p = 1.000). Both groups had similar rates of malignancy, mortality and CMV/BK viremia.

CONCLUSION

Non-belatacept (MMF, tacrolimus and sirolimus) and belatacept-based (MMF, tacrolimus and belatacept) regimens do not appear to pose any increased risk of early onset PTLD. Both cohorts benefited from low rates of rejection, malignancy, mortality and graft failure. Recipients will continue to be monitored as PTLD can manifest as a long-term complication.

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.

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.

Spleen-Restricted Posttransplant Lymphoproliferative Disorder in the First Year After Kidney Transplant - A Case Report

Posttransplant lymphoproliferative disorders (PTLDs) are a feared complication after transplant. They are mostly of B cell origin and are frequently Epstein-Barr virus (EBV)-positive, particularly in early onset PTLD. Later on, non-B and EBV-negative PTLD are increasingly reported. EBV seronegative receptors (particularly when paired with an EBV seropositive donor) together with the net degree of immunosuppression-a concept often difficult to quantify-are the most consistently described risk factors for the development of PTLD. Conversely, its association with a particular immunosuppressive agent or other virus, namely cytomegalovirus (CMV) infection or disease, has been inconsistently reported. We present a challenging case where an EBV negative monomorphic peripheric T-cell lymphoma was diagnosed in the first year after kidney transplant in a patient with a recent history of CMV disease from a resistant strain.

Human genetic polymorphisms and risk of viral infection after solid organ transplantation

The immune system plays a key role in the host defense against viral pathogens. A signaling cascade is activated upon infection involving a variety of molecules such as pattern-recognition receptors (PRRs), interleukins or antiviral interferons. Long-term immunosuppression after solid organ transplantation (SOT) mainly abrogates adaptive T-cell-mediated responses, thus highlighting the relative contribution of innate immunity. Single-nucleotide polymorphisms (SNPs) within genes coding for PRRs or soluble mediators have been associated with differential susceptibility to viral infections among SOT recipients. A protective effect against cytomegalovirus (CMV) infection or disease has been attributed to certain SNPs in TLR9 or IFNL3 genes, whereas the opposite effect has been attributed to genetic polymorphisms in TLR2, MBL2, DC-SIGN, IL10 or IFNG. The presence of SNPs in other molecules not directly involved in innate or adaptive immune responses such as aquaporins or pregnane X appear to modulate the risk of CMV or BK polyomavirus infection, respectively. Little information is available on the genetic determinants of the post-transplant susceptibility to herpesviruses causing clinical infection (herpes simplex virus or varicella zoster virus) or the replication kinetics of components of the human blood virome used as immune surrogates (Torque teno virus). The present review critically summarizes the current knowledge on how SNP genotyping would be useful to stratify SOT recipients according to the individual risk of viral infection and proposes next research steps. Genetic susceptibility testing may improve personalized medicine and contribute to minimize the risk of viral infection after SOT.

Successful Treatment of Acute Kidney Allograft Rejection using Extracorporeal Photopheresis in the Context of Post-Transplant Lymphoproliferative Diseases: 3 Successive Cases

Kidney allograft loss occurs within 2 years in one third of patients with post-transplant lymphoproliferative disease (PTLD). Acute rejection (AR) risk is increased as a result of strong immunosuppression minimization following PTLD (1-3). Here, we report extracorporeal photopheresis (ECP) use in three successive kidney transplant recipients for treatment of concomitant acute cellular and humoral rejection occurring after immunosuppression minimization following PTLD diagnosis.

Current Practices on Diagnosis, Prevention and Treatment of Post-Transplant Lymphoproliferative Disorder in Pediatric Patients after Solid Organ Transplantation: Results of ERN TransplantChild Healthcare Working Group Survey

(1) Background: Post-transplant lymphoproliferative disease (PTLD) is a significant complication of solid organ transplantation (SOT). However, there is lack of consensus in PTLD management. Our aim was to establish a present benchmark for comparison between international centers and between various organ transplant systems and modalities; (2) Methods: A cross-sectional questionnaire of relevant PTLD practices in pediatric transplantation was sent to multidisciplinary teams from 17 European center members of ERN TransplantChild to evaluate the centers’ approach strategies for diagnosis and treatment and how current practices impact a cross-sectional series of PTLD cases; (3) Results: A total of 34 SOT programs from 13 European centers participated. The decision to start preemptive treatment and its guidance was based on both EBV viremia monitoring plus additional laboratory methods and clinical assessment (61%). Among treatment modalities the most common initial practice at diagnosis was to reduce the immunosuppression (61%). A total of 126 PTLD cases were reported during the period 2012–2016. According to their histopathological classification, monomorphic lesions were the most frequent (46%). Graft rejection after PTLD remission was 33%. Of the total cases diagnosed with PTLD, 88% survived; (4) Conclusions: There is still no consensus on prevention and treatment of PTLD, which implies the need to generate evidence. This might successively allow the development of clinical guidelines.