Post‐transplant lymphoproliferative disorders with naso‐ and oropharyngeal manifestation

The nasopharyngeal/oropharyngeal lymphatic tissues represent the anatomical site of Epstein–Barr virus (EBV) entry. Post‐transplant lymphoproliferative disorders (PTLD) are often associated with EBV, but little is known about the characteristics of nasopharyngeal/oropharyngeal mass‐forming PTLD. Retrospective evaluation of our own PTLD database (n = 79) and the PubMed^® database (n = 61) has been performed. Sinonasal/oro‐/nasopharyngeal lymphatic masses were early lesions (n = 54/140, 38.5%), polymorphic PTLD (n = 32/140, 23%), monomorphic B‐PTLD (n = 47/140, 33.5%) and T‐PTLD (n = 7/140, 5%). One‐fourth of lesions manifested as masses in the Waldeyer's ring, and in two‐thirds of cases, swelling of tonsils was related to manifestation of benign early lesions. Tonsil infiltration by polymorphic PTLD and monomorphic PTLD was present in one‐third of cases. Extratonsillar masses were mainly monomorphic PTLD. Meta‐analysis of our data in combination with previously published data revealed that lung transplantation and young patients are at a higher risk for earlier manifestation of monomorphic PTLD. Therapy is similar to PTLD therapy strategies, in general reduced immunosuppression and chemotherapy for polymorphic and monomorphic PTLD, and diagnostic and therapeutic surgical gross tumour resection of tonsillar/adenoid lesions. In summary, it is relevant for the clinical differential diagnosis that oro‐/nasopharyngeal aggressive PTLD manifested in ~30% as tonsillar masses and >90% at extratonsillar sites.     

Transplantation of solid organ recipients shedding Epstein‐Barr virus DNA pre‐transplant: A prospective study

Epstein‐Barr virus (EBV) poses a significant threat to patient and graft survival post‐transplant. We hypothesized that recipients who shed EBV at transplant had less immunologic control of the virus and hence were more likely to have active EBV infection and disease post‐transplant. To test this hypothesis, we conducted a 5‐year prospective study in primary solid organ transplant recipients. We measured EBV DNA in oral washes and blood samples by quantitative PCR before transplant and periodically thereafter for up to 4 years. Pre‐transplant samples were available from 98 subjects. EBV DNA was detected pre‐transplant in 32 of 95 (34%) and 5 of 93 subjects (5%) in oral wash and blood, respectively. Recipients with and without detectable pre‐transplant EBV DNA were not significantly different demographically and had no significant difference in patient and graft survival (P = .6 for both comparisons) or post‐transplant EBV viremia‐free survival (P = .8). There were no cases of EBV‐related disease or post‐transplant lymphoproliferative disorder (PTLD) in any of the patients with detectable EBV DNA pre‐transplant. In conclusion, detectable EBV DNA pre‐transplant was not associated with differences in patient/graft survival, post‐transplant EBV viremia, or EBV‐related diseases including PTLD.     

Post‐transplant lymphoproliferative disease in lung transplantation: A nested case‐control study

Post‐transplant lymphoproliferative disorder (PTLD) may compromise long‐term outcome of lung transplant (LTx) recipients. A case‐control study was performed, comparing LTx recipients with PTLD (n=31) to matched recipients without PTLD (Controls, n=62). Risk factors for PTLD and post‐transplant outcomes were assessed. PTLD prevalence was 3.9%, time to PTLD 323 (166‐1132) days; and 54.8% had early‐onset PTLD versus 45.2% late‐onset PTLD. At LTx, more Epstein‐Barr virus (EBV)‐seronegative patients were present in PTLD (42%) compared to Controls (5%) (P<.0001); most of whom had undergone EBV seroconversion upon PTLD diagnosis. EBV viral load was higher in PTLD versus Controls (P<.0001). Overall, lower hemoglobin and higher C‐reactive protein levels were present in PTLD versus Controls (P<.0001). EBV status at LTx (P=.0073) and EBV viral load at PTLD (P=.0002) were the most important risk determinates for later PTLD. Patients with PTLD demonstrated shorter time to onset of chronic lung allograft dysfunction (CLAD) (P=.0006) and poorer 5‐year survival post‐LTx (66.6% versus 91.5%), resulting in worse CLAD‐free survival (HR 2.127, 95%CI 1.006‐4.500; P=.0483) and overall survival (HR 3.297 95%CI 1.473‐7.382; P=.0037) compared to Controls. Late‐onset PTLD had worse survival compared to early‐onset PTLD (P=.021). Primary EBV infection is a risk for PTLD; which is associated with worse long‐term outcome post‐LTx.     

Circulating Epstein‐Barr virus DNA to monitor lymphoproliferative disease following pediatric liver transplantation

Abstract Epstein‐Barr virus (EBV) infection can induce uncontrolled lymphocyte B proliferation in immunosuppressed transplant patients. Monitoring circulating EBV‐infected lymphocytes can help in identifying patients at risk of post‐transplant lymphoproliferative disease (PTLD). Circulating EBV genome levels were determined in 54 liver transplant pediatric recipients. Ten patients had more than 500 EBV genome/10⁵ peripheral blood lymphocytes (PBL) and exhibited clinical manifestations of EBV infection; three developed PTLD. To treat EBV infection, the level of immunosuppression was reduced and acute rejection developed in 4 patients. Three were treated with steroid and one had to be switched from cyclosporine to tacrolimus. Treatment of acute rejection was associated with increases in circulating EBV genome. None of the patients with less than 500 EBV genome/10⁵ PBL developed PTLD or EBV infection. Monitoring of EBV DNA is useful in the management of EBV infection and PTLD following pediatric liver transplantation. EBV infection should be treated in ways which do not expose patients to the risk of rejection.     

Epstein‐Barr virus load in whole blood is associated with immunosuppression,but not with post‐transplant lymphoproliferative disease in stable adult heart transplant patients

Development of Epstein‐Barr virus (EBV)‐associated post‐transplant lymphoproliferative disease (PTLD) is a serious complication following heart transplantation (HTX). This study investigates EBV DNA load in adult heart transplant recipients, its association with immunosuppression, and its potential as a marker for development of PTLD. EBV DNA load was measured prospectively by quantitative real‐time polymerase chain reaction (PCR) in 172 stable HTX patients. Sixty‐seven patients (39.0% of total) had a positive EBV PCR at initial examination [median 4.9 (range 1.1–16.9) years post‐HTX]. In follow‐up testing of 67 positive patients 6 months later, 36 patients continued to have a positive EBV PCR. Overall incidence of EBV DNA was significantly associated with calcineurin inihibitors, azathioprine medication, and with the absence of mycophenolate mofetil (MMF) treatment. In patients with positive EBV DNA levels at initial examination and negative levels at retesting, cyclosporine A levels were found to be significantly higher at initial examination (148.4 ± 70.2 vs. 119.6 ± 53.5 ng/ml, P < 0.05). Three patients (1.7%, 3/172) were diagnosed with PTLD during the course of the study (mean follow up 4.0 years). EBV DNA viral load determination does not appear to be useful for risk prediction or early diagnosis of PTLD in adults after HTX, but an association of EBV DNA load with qualitative and quantitative immunosuppression is demonstrated.     

Characteristics,risks, and outcomes of post‐transplant lymphoproliferative disease >3 years after pediatric heart transplant: A multicenter analysis

Post‐transplant lymphoproliferative disorder (PTLD) is a significant complication after pediatric heart transplantation (HT), occurring in 5%‐15% of patients within 3 years. Data >3 years from HT are limited. We sought to describe the prevalence, risk factors, and outcomes of PTLD occurring late (>3 years) after pediatric HT in the Pediatric Heart Transplant Study from 1993 to 2010. Among 3844 primary HT patients, 110 (3%) developed late, nonrecurrent PTLD. The hazard rate for late PTLD was constant at 0.01 events/year out to 20 years after HT. Risk factors for late PTLD were younger age at HT (HR 1.06, P = 0.003) and Epstein‐Barr virus (EBV) naivety (HR 1.65, P = 0.02). Survival after late PTLD was 86% and 68% at 1 and 5 years, with nonwhite race (HR 2.27, P = 0.03) and earlier year of HT (HR 1.03, P = 0.04) independently associated with mortality. Acute rejection and infection were both common after late PTLD, occurring in 26% and 34% of patients. The constant late hazard and contribution of EBV to late PTLD suggest that vigilance for development of PTLD, including for EBV conversion, should persist indefinitely after pediatric HT. The reasons for elevated risk of death for nonwhites after late PTLD are unclear and warrant further investigation.     

Risk factors for post‐transplant lymphoproliferative disorder after Thymoglobulin‐conditioned hematopoietic cell transplantation

Epstein‐Barr virus (EBV)‐induced post‐transplant lymphoproliferative disorder (PTLD) occurs frequently when rabbit antithymocyte globulin (ATG) is used in hematopoietic cell transplant (HCT) conditioning. We retrospectively studied 554 patients undergoing ATG‐conditioned myeloablative HCT. Strategies used to minimize mortality due to PTLD were either therapy of biopsy‐diagnosed PTLD in the absence of EBV DNAemia monitoring (n = 266) or prompt therapy of presumed PTLD (based on clinical/radiologic signs and high EBV DNAemia, in the setting of weekly EBV DNAemia monitoring) (n = 199). Both strategies resulted in similar mortality due to PTLD (0.7% vs 1% at 2 years, P = .43) and similar overall survival (63% vs 67% at 2 years, P = .23) even though there was a trend toward higher PTLD incidence with the prompt therapy. Donor positive with recipient negative EBV (D+R?) serostatus was a risk factor for developing PTLD. Older patient age, HLA‐mismatched donor, and graft‐versus‐host disease were not associated with increased risk of PTLD. In summary, in ATG‐conditioned HCT, D+R? serostatus, but not older age, mismatched donor or GVHD is a risk factor for developing PTLD. EBV DNAemia monitoring may be a weak risk factor for developing/diagnosing PTLD; the monitoring coupled with prompt therapy does not improve survival.     

Epstein–Barr Virus‐Related Post‐Transplant Lymphoproliferative Disorders: Pathogenetic Insights for Targeted Therapy

Post‐transplant lymphoproliferative disorder (PTLD) is a spectrum of major, life‐threatening lymphoproliferative diseases occurring in the post‐transplant setting. The majority of PTLD is of B‐cell origin and is associated with several risk factors, the most significant being Epstein‐Barr virus (EBV) infection. EBV's in vitro transforming abilities, distinctive latency, clonality within the malignant cells and response to targeted therapies implicate a critical role in the biology of PTLD. This minireview focuses on EBV‐related PTLD pathogenesis, in particular the interplay between aspects of the EBV life cycle and latency with nonviral factors resulting in the wide spectrum of histology and clinical presentations encountered in PTLD. With the increased prevalence of transplantation a rise in the incidence of PTLD may be expected. Therefore the importance of laboratory and animal models in the understanding of PTLD and the development of novel therapeutic approaches is discussed.     

Plasmacytic post‐transplant lymphoproliferative disorder: a case series of nine patients

Post‐transplant lymphoproliferative disorder (PTLD) is a serious complication of organ transplantation. Although PTLD typically has a B‐cell histology, an uncommon variant, plasmacytic PTLD can present as a monoclonal plasma cell proliferation similar to plasmacytomas seen in multiple myeloma. A retrospective analysis was performed on nine patients at our center with plasmacytic PTLD as characterized by plasmacytic histology with the presence of CD138 and lack of CD20. Of the 210 adult solid organ transplant PTLD patients diagnosed between 1988 and 2012, 9 (4%) had a histological appearance consistent with plasmacytic PTLD. The median time from transplant to diagnosis was 3.7 years (range 8 months–24 years). All patients presented with extranodal and often subcutaneous solid tumors. Laboratory features included elevated LDH and beta‐2 microglobulin levels, monoclonal gammopathy, and EBV positivity of the tumor. Unlike conventional multiple myeloma, patients had normal calcium levels and only mild anemia. Six patients who have completed treatment achieved complete responses with radiation therapy and/or reduction in immunosuppression with two patients now greater than 5 years in continuous complete response. Plasmacytic PTLD, despite its plasmacytic histology, is responsive to conventional therapies used for B‐cell PTLD including reduction in immunosuppression and radiation therapy.     

Lymphoproliferative disorders in heart transplant recipients: role of hepatitis C virus (HCV) and Epstein‐Barr virus (EBV) infection

Abstract Post‐transplant lymphoproliferative disorders (PTLD) are a well known complication after orthotopic heart transplantation (OHT). Although Epstein‐Barr virus (EBV) infection has long been implicated in the pathogenesis of such disorders, other factors may play a part. Because of its lymphotropic properties, hepatitis C virus (HCV) may induce clonal expansion of B‐lymphocytes and lead to PTLD. The aim of this study was to evaluate the potential association between HCV and EBV infection and PTLD in OHT patients. The retrospective study considered 404 adult patients screened for HCV. EBV serology, histology, and molecular analysis on tissue biopsies were performed in the PTLD patients (10/404, 2.5%). HCV positivity was found in 36/404 (8.9 %) patients. The EBV genome was expressed on all neoplastic tissue samples analyzed. A higher proportion of HCV‐positive patients developed PTLD than the HCV‐negative cases (8 % vs 2%, P = 0.017). EBV has a demonstrated role in the onset of PTLD, but HCV infection probably has to be considered as well.     

Post‐transplant lymphoproliferative disorder in adult liver transplant recipients: a South American multicenter experience

Post‐transplant lymphoproliferative disorder (PTLD) is a major and potentially life‐threatening complication after solid‐organ transplantation. The aim of this study was to describe the disease characteristics, clinical practices, and survival related to PTLD in adult orthotopic liver transplant (OLT) recipients in South America. We conducted a survey at four different transplant groups from Argentina, Brazil, and Chile. Among 1621 OLT recipients, 27 developed PTLD (1.7%); the mean age at diagnosis was 53.7 (±14) yr with a mean time of 39.7 (±35.2) months from OLT to PTLD diagnosis. Initial therapy included reduction in immunosuppression alone in 23.1% of the patients. Either rituximab or chemotherapy was employed as initial or second‐line therapy in 76.9% of the patients. PTLD location was frequently extranodal (80.7%) and mostly involving the transplanted liver (59.3%). The overall survival at one and five yr post‐PTLD diagnosis was 53.8% and 46.2%, respectively. Significant univariate risk factors for post‐PTLD mortality included lactate dehydrogenase ≥250 U/L (HR 9.66, p = 0.02), stage III/IV PTLD (HR 5.34, p = 0.004), and HCV infection (HR 7.68, p = 0.01). In conclusion, PTLD in OLT adult recipients is predominantly extranodal, and although mortality is high, long‐term survival is possible.     

Clinical and virologic outcomes in high‐risk adult Epstein‐Barr virus mismatched organ transplant recipients

Epstein‐Barr virus (EBV) D+/R? organ transplant recipients are a high‐risk group for developing post‐transplant lymphoproliferative disease (PTLD). Little data are available for prevention in the adult EBV mismatched population. We conducted a retrospective study of EBV D+/R? organ transplants performed during 2002‐2014. Of the 153 patients identified, 82.4% patients received antiviral prophylaxis with valganciclovir for a median of 4.5 months (range: 0.8‐22 months) and 36.6% underwent viral load monitoring in the first post‐transplant year. EBV viremia developed in 67.2% monitored patients. In viremic patients, immunosuppression was reduced in 20/37(54.1%) in response to viremia and 17/37 (45.9%) received therapeutic dose valganciclovir. In patients with EBV viremia who received valganciclovir and/or had a reduction in immunosuppression and had sufficient viral load time points (n=31), 28 (90.3%) had a significant decline in viral load at day 14 (median log decline 0.49 (0.24‐0.64), P<.001) and at day 30 (0.87 (0.52‐1.21), P<.001). PTLD developed in 27 (15%) patients (biopsy proven=25, possible=2) at median 8 months (range: 2.4‐130) post‐transplant with the majority (81.5%) within the first year. In multivariate analysis, viral load monitoring and use of mycophenolate were associated with a lower incidence of PTLD. Antiviral prophylaxis was not associated with a lower risk of PTLD, but viral load monitoring and use of mycophenolate mofetil were protective.     

IL‐6 and IL‐10 in post‐transplant lymphoproliferative disorders development and maintenance: a longitudinal study of cytokine plasma levels and T‐cell subsets in 38 patients undergoing treatment

IL‐6 and IL‐10 have previously been implicated in the pathogenesis of post‐transplant lymphoproliferative disorders (PTLD) and, like peripheral lymphocyte populations, are markers of immune status that are amenable to study in vivo. Thus, we analyzed cytokine plasma levels as well as lymphocyte subsets in a longitudinal analysis of 38 adult transplant recipients undergoing treatment for PTLD. Pretherapeutically, we found significantly elevated IL‐6 (13.8 pg/ml) and IL‐10 plasma levels (54.7 pg/ml) – in the case of IL‐10, even higher in treatment nonresponders than in responders (116 vs. 14 pg/ml). Over time, however, IL‐10 levels did not correlate with the course of disease, whereas those of IL‐6 did, falling in responders and rising in nonresponders. These findings were independent of histological EBV‐status, treatment type, and total peripheral T‐cell counts, which were significantly reduced in patients with PTLD. Our observations support the idea that although IL‐10 is important for creating a permissive environment for post‐transplant lymphoma development, IL‐6 is associated with PTLD proliferation. The analysis of lymphocyte subsets further identified HLA‐DR+ CD8+ lymphocyte numbers as significantly different in non‐PTLD controls (33%), treatment responders (44%) and nonresponders (70%). Although the specificity of these cells is unclear, their increase might correlate with the impaired tumor‐specific cytotoxic‐T‐lymphocyte (CTL)‐response in PTLD.     

Clinical characteristics and outcomes of PTLD following intestinal transplantation

Post‐transplant lymphoproliferative disease (PTLD) has the highest incidence following intestinal transplantation (ITx). Our center has seen a recent increase in PTLD. Our aim was to review a single‐center PTLD experience with a focus on clinical characteristics and outcomes. We completed a retrospective review of biopsy‐proven PTLD cases using a prospectively maintained database of 115 ITx recipients transplanted between 1991 and 2014. Nineteen (17%) ITx recipients developed 25 PTLD cases during a median follow‐up time of 6.4 (1.6‐14.6) years. The incidence of early PTLD was 6% (n = 7). There was a trend toward increased risk of PTLD in children compared with adults (P = .11) and a significantly increased risk of PTLD in re‐ITx compared with primary ITx recipients (P = .03). Most PTLD cases were diagnosed between 2010 and 2014 (n = 14). All early PTLD cases were EBV+ on in situ hybridization. Overall graft and patient survival are 68% and 74%, respectively. Second episodes of PTLD were diagnosed in 43% of surviving pediatric patients. Our program has a low incidence of early PTLD with overall excellent graft and patient survival following diagnosis. However, we have also seen a rising incidence of late PTLD. The cause of the increase is unknown as no major changes in immunosuppression protocols have occurred since 1999.     

Idiopathic pulmonary fibrosis lung transplant recipients are at increased risk for EBV‐associated posttransplant lymphoproliferative disorder and worse survival

Epstein‐Barr virus (EBV)–associated posttransplant lymphoproliferative disorder (EBV‐PTLD) is a serious complication in lung transplant recipients (LTRs) associated with significant mortality. We performed a single‐center retrospective study to evaluate the risks for PTLD in LTRs over a 7‐year period. Of 611 evaluable LTRs, we identified 28 cases of PTLD, with an incidence of 4.6%. Kaplan‐Meier analysis showed a decreased freedom from PTLD in idiopathic pulmonary fibrosis (IPF)‐LTRs (P < .02). Using a multivariable Cox proportional hazards model, we found IPF (hazard ratio [HR] 3.51, 95% confidence interval [CI] 1.33‐8.21, P = .01) and alemtuzumab induction therapy (HR 2.73, 95% CI 1.10‐6.74, P = .03) as risk factors for PTLD, compared to EBV mismatch (HR: 34.43, 95% CI 15.57‐76.09, P < .0001). Early PTLD (first year) was associated with alemtuzumab use (P = .04), whereas IPF was a predictor for late PTLD (after first year) (P = .002), after controlling for age and sex. Kaplan‐Meier analysis revealed a shorter time to death from PTLD in IPF LTRs compared to other patients (P = .04). The use of alemtuzumab in EBV mismatch was found to particularly increase PTLD risk. Together, our findings identify IPF LTRs as a susceptible population for PTLD. Further studies are required to understand the mechanisms driving PTLD in IPF LTRs and develop strategies to mitigate risk.     

Monitoring Infection with Epstein–Barr Virus among Seromismatch Adult Renal Transplant Recipients

Patients who undergo Epstein–Barr virus (EBV) seromismatch (D+/R − ) transplants have a higher risk for the development of post‐transplant lymphoproliferative disorder (PTLD). Adult renal transplant recipients at a single institution were prospectively monitored for EBV during the first year post‐transplant. Over a 2‐year period, 34 patients (7.78%) were identified as being EBV D+/R − recipients. Patients who developed symptoms or had persistent viremia were pre‐emptively administered rituximab. Six recipients were discharged without monitoring on the protocol. Of those six, three (50%) developed PTLD and all three lost their grafts. Twenty (60.6%) of the 34 recipients developed viremia during the first year post‐transplant. Of the recipients who became viremic, six (30%) received rituximab. None of the six who received rituximab‐developed PTLD. We found that recipients who were not monitored on the protocol were more likely to have PTLD and graft loss compared to those who were (p = 0.008). Post‐transplant monitoring of adults who undergo EBV D+/R − kidney transplants for viremia and symptoms associated with EBV infection may prompt intervention which reduces the incidence of PTLD within the first year. Use of rituximab in preventing PTLD among patients with primary EBV infection requires further prospective study to determine its overall safety and efficacy.     

A quantitative assay for Epstein-Barr Virus-specific immunity shows interferon-gamma producing CD8+ T cells increase during immunosuppression reduction to treat posttransplant lymphoproliferative disease

Reduction of immunosuppression (RIS) to allow development or recovery of Epstein-Barr virus (EBV) immunity can be used to treat EBV-associated posttransplant lymphoproliferative disease (PTLD). Quantification of EBV-specific immunity would help assessment of the efficacy of RIS therapy. Use of intracellular cytokine staining and analysis by flow cytometry to monitor functional EBV-specific T-cell immunity was evaluated in healthy volunteers. The technique was then used to monitor EBV immunity in nine renal transplant patients with PTLD during RIS. The number of interferon (IFN)-gamma producing CD8+ T cells specific for EBV increased distinctly before regression of EBV+ PTLD tumors occurred. The findings confirm the importance of IFN-gamma producing CD8+ T cells in controlling the malignant EBV-transformed B cells of PTLD. The assay effectively quantified EBV immunity during RIS in transplant patients with PTLD.     

Association of HLA Polymorphisms with Post‐transplant Lymphoproliferative Disorder in Solid‐Organ Transplant Recipients

The association between HLA polymorphisms and PTLD was investigated in a case–control study, comparing 110 predominantly adult solid‐organ transplant recipients who developed PTLD to 5601 who did not. Donor and recipient HLA were analyzed. We detected a significant association between recipient HLA‐A26 and the development of PTLD (OR 2.74; p = 0.0007). In Caucasian recipients, both recipient and donor HLA‐A26 were independently associated with development of PTLD (recipient A26 OR 2.99; p = 0.0004, donor A26 OR 2.81; p = 0.002). Analysis of HLA‐A and ‐B haplotypes revealed that recipient HLA‐A26, B38 haplotype was strongly correlated with a higher incidence of EBV‐positive PTLD (OR 3.99; p = 0.001). The common ancestral haplotype HLA‐A1, B8, DR3, when carried by the donor, was protective against PTLD (OR 0.41; p = 0.05). Several other HLA specificities demonstrated associations with clinical and pathological characteristics as well as survival. These findings demonstrate the importance of HLA polymorphisms in modulating the risk for PTLD, and may be useful in risk stratification and development of monitoring and prophylaxis strategies.     

Graft outcomes following diagnosis of post‐transplant lymphoproliferative disease in pediatric kidney recipients: a retrospective study

Data related to graft outcomes following post‐transplant lymphoproliferative disease (PTLD) in pediatric kidney transplantation are scarce. Data were analyzed retrospectively from 12 children (eight boys) for 3 years after diagnosis of PTLD, with a loss of follow‐up after 2 years in two of 12. In all cases, intensity of immunosuppressive therapy was reduced, which switched from calcineurin inhibitor to a mammalian target of rapamycin (mTOR) inhibitor in ten cases. Nine children were treated with six doses of rituximab according to the PED‐PTLD‐2005 protocol, with additional treatment in one child as per protocol. One patient received EuroNet‐PHL C1. In four patients, donor‐specific antibodies were detected after PTLD diagnosis at 3, 4, 5 and 7 years, respectively. One patient developed chronic antibody‐mediated rejection (cAMR) 12 years after diagnosis, losing the graft 1 year later. Three patients with recurrence of the original disease also lost their grafts, one at the time of diagnosis of PTLD, and two after 4 years. Range‐based analysis of variance showed that there was no decrease in estimated GFR at 1, 2, or 3 years after diagnosis of PTLD (P = 0.978). In conclusion, treatment of PTLD with reduced immunosuppression is safe and efficient. This may be due to B‐cell‐depleting therapy of PTLD with rituximab.     

EBV‐Associated Leukoencephalopathy with Late Onset of Central Nervous System Lymphoma in a Kidney Transplant Recipient

Central nervous system (CNS) lymphoma is a rare posttransplant lymphoproliferative disorder (PTLD), which usually has a poor outcome. To date, no specific conditions predisposing to this complication have been identified. We here describe the case of a renal transplant patient who was initially diagnosed as having Epstein‐Barr virus (EBV)‐associated leukoencephalopathy and ultimately developed EBV‐positive CNS lymphoma. The patient was a young lady who, 2 years after transplantation, presented with focal neurological and electroencephalographic abnormalities and diffuse white matter lesions on brain magnetic resonance imaging. EBV‐DNA was detected in the cerebrospinal fluid (CSF) by polymerase chain reaction. After acyclovir therapy and immunosuppressive drug tapering, the symptoms and electroencephalographic abnormalities subsided, and EBV‐DNA disappeared from the CSF. Ten years later, a bulky cerebral mass was found. After excision, a diagnosis of EBV‐positive, Hodgkin‐like monomorphic B‐cell PTLD was made. This case illustrates the potential pathophysiological relationships between EBV infection, leukoencephalopathy and CNS lymphoma; although a long time elapsed from the initial neurological illness to CNS lymphoma, a link between these two conditions cannot be excluded. Therefore, a careful long‐term follow‐up of EBV‐related encephalopathy is advisable.