Tumour necrosis factor gene polymorphism: a predictive factor for the development of post-transplant lymphoproliferative disease

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

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

A Pathology Experience of Posttransplant Lymphoproliferative Disorder From One Tertiary Hospital: Pathology Concepts and Diagnostic Approach

BACKGROUND

Solid organ transplantation and bone marrow/hematologic stem cell transplantation recipients face a heightened risk of developing malignancies or cancer as a result of immunosuppression. Posttransplant lymphoproliferative disorders (PTLD) are a range of disorders from benign lymphoid growth to lymphoma found post-transplant. Risk factors for PTLD include high immunosuppressive use and oncogenic effects of Epstein-Barr virus (EBV). There is a lack of comprehensive clinical and pathological documentation of PTLD cases among Saudi patients, and the available data are limited to a few case reports. As a result, a deeper understanding of this disease requires more clinicopathological information.

MATERIAL AND METHOD

In this review, we share our insights on cases diagnosed with PTLD at King Faisal Specialist Hospital and Research Center, a prominent tertiary center in the western region of Saudi Arabia, from 2005-2023.

RESULT

We have diagnosed a total of 14 cases of PTLD in our department, with an age range spanning from 3 to 62 years. These diagnoses were made based on biopsies or tumor resection procedures. The survival rate of patients is believed to be influenced by multiple factors, including histology, tumorigenesis, disease biology, and clinical stage. Additionally, Kaplan-Meier curve analysis indicates that female patients tend to have a higher estimated survival rate compared to males.

CONCLUSION

PTLD diagnosis and therapy have greatly improved in the past 20 years. PTLD is treated with reduced immunosuppression, rituximab, chemotherapy, adoptive therapy, surgery, antiviral therapy, and radiotherapy. In this study, we present our experience from a large tertiary center in the western region of Saudi Arabia. Moreover, we will go through etiology, clinical features, and pathologic morphology along with the corresponding genetics, prevention, and valid treatment options.

The role of soluble mediators in the clinical course of EBV infection and B cell homeostasis after kidney transplantation

Epstein-Barr virus (EBV) reactivation can lead to serious complications in kidney transplant patients, including post-transplant lymphoproliferative disorder (PTLD). Here, we have assessed the impact of EBV on B cell homeostasis at cellular and humoral level. In a multicenter study monitoring 540 kidney transplant patients during the first post-transplant year, EBV reactivation was detected in 109 patients. Thirteen soluble factors and B cell counts were analyzed in an EBV+ sub-cohort (N = 54) before, at peak and after EBV clearance and compared to a control group (N = 50). The B cell activating factor (BAFF) was significantly elevated among EBV+ patients. No additional soluble factors were associated with EBV. Importantly, in vitro experiments confirmed the proliferative effect of BAFF on EBV-infected B cells, simultaneously promoting EBV production. In contrast, elevated levels of BAFF in EBV+ patients did not lead to B cell expansion in vivo. Moreover, diminished positive inter-correlations of soluble factors and alterations of the bi-directional interplay between B cell and soluble factors were observed in EBV+ patients at peak and after clearance. Our data suggest that such alterations may counteract the proliferative effect of BAFF, preventing B cell expansion. The role of these alterations in lymphoma development should be analyzed in future studies.

Biomarkers for PTLD diagnosis and therapies

Post-transplant lymphoproliferative disorder (PTLD) represents a spectrum of lymphoproliferative disorders and is a serious complication of pediatric transplantation. The majority of PTLD are associated with Epstein Barr virus (EBV) and the characteristic EBV+ B cell lymphomas are the leading post-transplant malignancy in children. EBV+ PTLD remains a formidable issue in pediatric transplantation and is thought to result from impaired immunity to EBV as a result of immunosuppression. However, the key viral and immune factors that determine whether EBV+ PTLD develops remain unknown. Recently, there has been much interest in developing biomarkers in order to improve and achieve more personalized approaches, in the clinical diagnosis, management, and treatment of EBV+ PTLD. Here, we review the status of immune-, viral-, and B cell lymphoma-derived candidates for biomarkers of EBV+ PTLD.

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

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

Post-transplant lymphoproliferative disorder in pediatric intestinal transplant recipients: A literature review

Intestinal transplantation is a successful treatment for children with intestinal failure, but has many potential complications. PTLD, a clinically and histologically diverse malignancy, occurs frequently after intestinal transplantation and can be fatal. The management of this disease is particularly challenging. The rejection-prone intestinal allograft requires high levels of immunosuppression, a precondition for PTLD. While EBV infection clearly plays a role in disease pathogenesis, the relatively naïve immune system of children is another likely contributor. As a result, pediatric intestine recipients have a higher risk of developing PTLD than other solid organ recipients. Other risk factors for disease development such as molecular and genomic changes that precipitate malignant transformation are not fully understood, especially among children. Studies on adults have started to describe the molecular pathogenesis of PTLD, but the genomic landscape of the malignancy remains largely undefined in pediatric intestinal transplant patients. In this review, we describe what is known about PTLD in pediatric patients after intestinal transplant and highlight current knowledge gaps to better direct future investigations in the pediatric population.

Cytokine gene polymorphism associations with congenital cytomegalovirus infection and sensorineural hearing loss

Cytomegalovirus (CMV) is the most common viral agent of congenital infections and a leading nongenetic cause of sensorineural hearing loss (SNHL). The host immunologic factors that render a developing foetus prone to intrauterine CMV infection and development of hearing loss are unknown. The aim of this study was to assess the potential associations between the polymorphisms within cytokine and cytokine receptors genes, and the risk of congenital CMV infection, and the hearing outcome. A panel of 11 candidate single nucleotide polymorphisms (SNPs): TNF rs1799964, TNF rs1800629, TNFRSF1A rs4149570, IL1B rs16944, IL1B rs1143634, IL10 rs1800896, IL10RA rs4252279, IL12B rs3212227, CCL2 rs1024611, CCL2 rs13900, CCR5 rs333 was genotyped in 470 infants (72 with confirmed intrauterine CMV infection and 398 uninfected controls), and related to congenital CMV infection, and the outcome. In multivariate analysis, the IL1B rs16944 TT and TNF rs1799964 TC genotypes were significantly associated with intrauterine CMV infection (aOR = 2.32; 95% CI, 1.11–4.89; p = 0.032, and aOR = 2.17, 95% CI, 1.25–3.77; p = 0.007, respectively). Twenty-two out of 72 congenitally infected newborns had confirmed SNHL. Carriers of CT or TT genotype of CCL2 rs13900 had increased risk of hearing loss at birth and at 6 months of age (aOR = 3.59; p = 0.028 and aOR = 4.10; p = 0.039, respectively). This is the first study to report an association between SNPs in IL1B, TNF, and CCL2, and susceptibility to congenital CMV infection (IL1B and TNF) and SNHL (CCL2).

Human leukocyte antigen type and posttransplant lymphoproliferative disorder

BACKGROUND

Posttransplant lymphoproliferative disorder (PTLD) is an infrequent but serious complication of solid organ transplantation. Early detection and initiation of therapy may improve outcomes. The purpose of this study was to identify human leukocyte antigen (HLA) type as risk and prognostic factors for PTLD.

METHODS

A review was undertaken to identify PTLD cases treated at our institution over the past 25 years. Logistic regression and Cox Proportional Hazards were used to model risk factors for PTLD and clinical outcomes in patients with PTLD.

RESULTS

One hundred six cases of PTLD were identified with 1392 solid-organ transplant recipient controls. Epstein-Barr virus (EBV) seronegative status pretransplant (odds ratio [OR] = 7.61, 95% confidence interval [95% CI] = 3.83-15.1) and receipt of a nonkidney transplant were associated with an increased risk of PTLD. Being African American and receipt of a living-related kidney transplant were associated with a decreased risk of PTLD. The HLA-B40 group was a risk factor for PTLD in EBV-seronegative individuals (OR = 8.38, 95% CI = 2.18-32.3), whereas HLA-B8 was a risk factor for PTLD in EBV-seropositive individuals (OR = 3.29, 95% CI = 1.52-7.09). Specific HLA types were not associated with graft failure or mortality after PTLD diagnosis. In PTLD patients, central nervous system (CNS) involvement, bone marrow involvement, T-cell PTLD, and age were associated with increased mortality.

CONCLUSION

Human leukocyte antigen-B40 group and HLA-B8 were identified as novel susceptibility factors for PTLD in EBV-seropositive and EBV-seronegative individuals, respectively. Multicentered, large prospective studies of PTLD with correlative immunologic work are needed to test the significance of these observed associations.

Post-transplant lymphoproliferative disorders

Post-transplant lymphoproliferative disorders (PTLD) are a serious complication after solid organ or allogeneic hematopoietic stem cell transplantation and include a range of diseases from benign proliferations to malignant lymphomas. Risk factors for developing PTLD include Epstein-Barr virus (EBV) infection, recipient age, transplanted organ, type of immunosuppression, and genetics. Uncontrolled proliferation of EBV-infected B cells is implicated in EBV-positive PTLD, whereas the pathogenesis of EBV-negative PTLD may be similar to non-Hodgkin's lymphoma in the general population. The World Health Organization (WHO) classifies PTLD into four categories: early lesions, polymorphic PTLD, monomorphic PTLD, and classical Hodgkin's lymphoma (cHL). Treatment is aimed at cure of PTLD, while maintaining transplanted organ function. However, there are no established guidelines for the treatment of PTLD. Immune suppression reduction (ISR) is the first line of treatment in most cases, with more recent data suggesting early use of rituximab. In more aggressive forms of PTLD, upfront chemotherapy may offer a better and more durable response. Sequential therapy using rituximab followed by chemotherapy has demonstrated promising results and may establish a standard of care. Novel therapies including anti-viral agents, adoptive immunotherapy, and monoclonal antibodies targeting cytokines require further study in the prevention and treatment of PTLD.

The association between the polymorphisms of TNF-α and non-Hodgkin lymphoma: a meta-analysis

Many genetic variations in the promoter region of tumor necrosis factor alpha (TNF-α) may confer host susceptibility to cancer by influencing TNF-α expression. Nevertheless, the results remain inconclusive. The current meta-analysis was performed to investigate the association between three common TNF-α promoter polymorphisms and the risk of non-Hodgkin lymphoma (NHL). A literature search was conducted mainly from PubMed for all eligible studies. The pooled odds ratios (ORs) and corresponding 95 % confidence intervals (CIs) were used to assess the association of TNF-α polymorphisms with the risk of NHL. TNF-α -308 A allele showed a statistically significant increased risk for NHL under the homozygous (AA vs. GG, OR = 1.51, 95 % CI = 1.26-1.80) and recessive (OR = 1.47, 95 % CI = 1.23-1.75) models, respectively. The stratified analyses showed an increased risk of NHL with the presence of TNF-α -308 A allele among Africans and Caucasians, but a decreased risk among Asians. No association was observed between -238 G/A polymorphism and NHL risk either in the overall analysis or in the stratified analysis. Similarly, pooled analysis did not reveal an altered risk of NHL with -857 C/T polymorphism. Nonetheless, a statistically significant association was observed among Asians when stratified by ethnicity. Among the three genetic variations of interest, TNF-α -308 G/A polymorphism was significantly associated with the risk of NHL; neither -238 G/A nor -857 C/T polymorphism was shown to alter the overall NHL risk; however, stratified analysis by ethnicity observed a statistically significant association between -857 C/T polymorphism and the risk of NHL among Asians.

Host genetics of Epstein-Barr virus infection, latency and disease

Epstein–Barr virus (EBV) infects 95% of the adult population and is the cause of infectious mononucleosis. It is also associated with 1% of cancers worldwide, such as nasopharyngeal carcinoma, Hodgkin's lymphoma and Burkitt's lymphoma. Human and cancer genetic studies are now major forces determining gene variants associated with many cancers, including nasopharyngeal carcinoma and Hodgkin's lymphoma. Host genetics is also important in infectious disease; however, there have been no large-scale efforts towards understanding the contribution that human genetic variation plays in primary EBV infection and latency. This review covers 25 years of studies into host genetic susceptibility to EBV infection and disease, from candidate gene studies, to the first genome-wide association study of EBV antibody response, and an EBV-status stratified genome-wide association study of Hodgkin's lymphoma. Although many genes are implicated in EBV-related disease, studies are often small, not replicated or followed up in a different disease. Larger, appropriately powered genomic studies to understand the host response to EBV will be needed to move our understanding of the biology of EBV infection beyond the handful of genes currently identified. Fifty years since the discovery of EBV and its identification as a human oncogenic virus, a glimpse of the future is shown by the first whole-genome and whole-exome studies, revealing new human genes at the heart of the host–EBV interaction. © 2014 The Authors. Reviews in Medical Virology published by John Wiley & Sons Ltd.

Post-transplant lymphoproliferative disease (PTLD): risk factors, diagnosis, and current treatment strategies

Post-transplant lymphoproliferative diseases (PTLD) are heterogeneous lymphoid disorders ranging from indolent polyclonal proliferations to aggressive lymphomas that complicate solid organ or hematopoietic transplantation. Risk factors for PTLD include viral infections, degree of immunosuppression, recipient age and race, allograft type, and host genetic variations. Clinically, extra-nodal disease is common including 10-15 % presenting with central nervous system (CNS) disease. Most PTLD cases are B cell (5-10 % T/NK cell or Hodgkin lymphoma), while over one-third are EBV-negative. World Health Organization (WHO) diagnostic categories are: early lesions, polymorphic, and monomorphic PTLD; although in practice, a clear separation is not always possible. Therapeutically, reduction in immunosuppression remains a mainstay, and recent data has documented the importance of rituximab +/- combination chemotherapy. Therapy for primary CNS PTLD should be managed according to immunocompetent CNS paradigms. Finally, novel treatment strategies for PTLD have emerged, including adoptive immunotherapy and rational targeted therapeutics (e.g., anti-CD30 based therapy and downstream signaling pathways of latent membrane protein-2A).

Interleukin 28B gene polymorphisms and Epstein-Barr virus-associated lymphoproliferative diseases

OBJECTIVES

Single-nucleotide polymorphisms (SNPs) near the interleukin (IL) 28B gene encoding a type III interferon (IFN-λ) are the most important genetic predictors of treatment response to hepatitis C virus (HCV). This retrospective study was undertaken to determine any association between IL28B SNPs and the development of viraemia in Epstein-Barr virus (EBV)-driven acute infectious mononucleosis (IM) and post-transplant lymphoproliferative disease (PTLD).

METHODS

Genomic DNA extracted from plasma from 45 EBV seropositive controls and 46 acute IM, 23 non-PTLD (transplant) and 21 PTLD patients was tested by PCR for 2 SNPs within IL28B. EBV DNA levels were tested in IM and PTLD samples by a real-time quantitative PCR.

RESULTS

No significant differences were seen in SNP frequencies at rs12979860 and rs8099917 in IM and PTLD patients compared to EBV seropositive controls and transplant patients. EBV DNA levels were lower in IM and PTLD patients with CC (a favourable genotype in HCV) at rs12979860 compared to non-CC genotypes (p = 0.055). Acute IM patients with CC had significantly lower levels of EBV DNA in plasma compared to those with non-CC genotypes (p = 0.011).

CONCLUSIONS

Genotype CC may influence anti-viral responses of IFN-λ, thereby allowing better control of EBV viraemia during lymphoproliferation, particularly in IM.

Immune surveillance and lymphoid malignancy in immunocompromised host

Immune surveillance is a dynamic process that involves an intact immune system to identify and protect the host against tumor development. The increased understanding of the genetics, infections and hematological malignancies in congenital immune deficiency states supports the concept that impaired T cells and Natural-killer/T cells leads to B-cell lymphoma. Furthermore, severe combined immunodeficient mice are prone to spontaneous tumor development and therefore serve as experimental models. Here we discuss the acquired conditions and mechanisms involved in dysregulation of the immune system that lead to lymphoma. Preemptive strategies to improve immune regulation and response and restore a competent immune system may lead to a decrease in lymphoid malignancies.

Molecular pathogenesis of B-cell posttransplant lymphoproliferative disorder: what do we know so far?

Posttransplant lymphoproliferative disorder (PTLD) is a potentially fatal disease that arises in 2%-10% of solid organ and hematopoietic stem cell transplants and is most frequently of B-cell origin. This very heterogeneous disorder ranges from benign lymphoproliferations to malignant lymphomas, and despite the clear association with Epstein-Barr Virus (EBV) infection, its etiology is still obscure. Although a number of risk factors have been identified (EBV serostatus, graft type, and immunosuppressive regimen), it is currently not possible to predict which transplant patient will eventually develop PTLD. Genetic studies have linked translocations (involving C-MYC, IGH, BCL-2), various copy number variations, DNA mutations (PIM1, PAX5, C-MYC, RhoH/TTF), and polymorphisms in both the host (IFN-gamma, IL-10, TGF-beta, HLA) and the EBV genome to B-cell PTLD development. Furthermore, the tumor microenvironment seems to play an important role in the course of disease representing a local niche that can allow antitumor immune responses even in an immunocompromised host. Taken together, B-cell PTLD pathogenesis is very complex due to the interplay of many different (patient-dependent) factors and requires thorough molecular analysis for the development of novel tailored therapies. This review aims at giving a global overview of the currently known parameters that contribute to the development of B-cell PTLD.

The impact of cytokine gene polymorphisms on Epstein-Barr virus infection outcome in pediatric liver transplant recipients

BACKGROUND

Epstein-Barr virus (EBV) is associated with most cases of the post-transplant lymphoproliferative disorders developed during the first year after transplantation. The high EBV DNA load constitutes a major risk for the development of EBV-related lymphoproliferations. However, among transplant recipients there are patients with a chronically high viral load (CHVL) who do not develop lymphoproliferations. The polymorphism within cytokine genes might influence the susceptibility to, and contribute to the pathogenesis of the disease.

OBJECTIVES

The aim of this study was to analyze the genetic polymorphism in the selected cytokines with regard to EBV infection outcome in children after liver transplantation (LTx).

STUDY DESIGN

Thirteen cytokine/cytokine receptor polymorphisms were genotyped in 170 children after LTx, and related to: EBV DNAemia, CHVL onset and the length of CHVL carriage.

RESULTS

The study revealed: the protective effect of rare homozygous and heterozygous IL-1β-511 and IL-1 receptor antagonist (IL-1RN VNTR) genotypes against viremia within the first year after LTx (OR=0.28, p=0.0007 and OR=0.35, p=0.009, respectively); the protective effect of CC chemokine ligand 2 (CCL2)+1543CT and TT genotypes against CHVL onset (OR=0.38, p=0.042); and the prolonged CHVL-resolution in IL12B 3'untranslated region (3'UTR) AC individuals (p=0.034).

CONCLUSIONS

This data suggests that carriage of IL-1β-511CT/TT and/or IL-1RN VNTR 1.2/2.2 genotype may be beneficial for combating EBV infection. This is the first study reporting the association of CCL2 and IL12B gene polymorphisms with the CHVL carriage in pediatric LTx recipients.

Post transplant lymphoproliferative disorders: risk, classification, and therapeutic recommendations

OPINION STATEMENT

Post transplant lymphoproliferative disorder (PTLD) is a heterogeneous disease that may occur in recipients of solid organ transplants (SOT) and hematopoietic stem cell transplant. The risk of lymphoma is increased 20-120% compared with the general population with risk dependent in part on level of immune suppression. In addition, recent data have emerged, including HLA and cytokine gene polymorphisms, regarding genetic susceptibility to PTLD. Based on morphologic, immunophenotypic, and molecular criteria, PLTD are classified into 4 pathologic categories: early lesions, polymorphic, monomorphic, and classical Hodgkin lymphoma. Evaluation by expert hematopathology is critical in establishing the diagnosis. The aim of therapy for most patients is cure with the concurrent goal of preservation of allograft function. Given the pathologic and clinical heterogeneity of PTLD, treatment is often individualized. A mainstay of therapy remains reduction of immune suppression (RI) with the level of reduction being dependent on several factors (e.g., history of rejection, current dosing, and type of allograft). Outside of early lesions and/or low tumor burden, however, RI alone is associated with cure in a minority of subjects. We approach most newly-diagnosed polymorphic and monomorphic PTLDs similarly using frontline single-agent rituximab (4 weeks followed by abbreviated maintenance) in conjunction with RI. Frontline combination chemotherapy may be warranted for patients with high tumor burden in need of prompt response or following failure of RI and/or rituximab. Due to chemotherapy-related complications in PTLD, especially infectious, we advocate comprehensive supportive care measures. Surgery or radiation may be considered for select patients with early-stage disease. For PTLD subjects with primary CNS lymphoma, we utilize therapeutic paradigms similar to immunocompetent CNS lymphoma using high-dose methotrexate-based therapy with concurrent rituximab therapy and sequential high-dose cytarabine. Finally, novel therapeutic strategies, especially adoptive immunotherapy, should continued to be explored.

Soluble CD30: a serum marker for Epstein-Barr virus-associated lymphoproliferative diseases

The soluble form of CD30 (sCD30), a member of tumor necrosis factor receptor superfamily, has been used as a marker of disease activity in various lymphomas. Epstein-Barr virus (EBV) is a potent stimulator of CD30 expression. The study aims to evaluate whether sCD30 can be used as a diagnostic marker for EBV-associated infectious mononucleosis (IM) and post-transplant lymphoproliferative disease (PTLD). Plasma from EBV seropositive healthy controls (N = 90), acute IM patients (n = 90), non-PTLD heart/lung transplant recipients (N = 30) and EBV-positive PTLD patients (N = 23) was tested for sCD30 using a commercially available ELISA kit. EBV DNA was tested by real time quantitative polymerase chain reaction assay. Significantly higher sCD30 levels were observed in acute IM patients (median 242.9 ng/ml) compared to EBV seropositive controls (median 15.7 ng/ml; P < 0.0001). These levels were highest in IM patients within 14 days of onset of illness. PTLD patients had significantly higher sCD30 levels (median 94 ng/ml) than healthy controls (P < 0.0001) and transplant patients (median 27 ng/ml; P = 0.0007). EBV DNA was detected mostly in acute IM and PTLD patients. In both cases there was a significant correlation between sCD30 and EBV DNA levels in plasma (P < 0.0001). This study demonstrates that sCD30 and EBV DNA levels can be used as potential markers for diagnosis of IM and PTLD.

Post-transplant lymphoproliferative disorder in view of the new WHO classification: a more rational approach to a protean disease?

Post-transplant lymphoproliferative disorders (PTLDs) are serious, life-threatening complications of solid-organ transplantation (SOT) and bone marrow transplantation leading to a high mortality (30-60%). PTLD represents a heterogeneous group of lymphoproliferative diseases. They become clinically relevant because of the expansion of transplantation medicine together with the development of potent immunosuppressive drugs. Although the diagnostic morphological criteria of different forms of PTLD are commonly known, rapid and correct diagnosis is not always easy. Because of the limited number of clinical trials, a consensus is lacking on the optimal treatment of PTLD. This review focuses on incidence, risk factors, clinical picture of the disease and diagnostic tools including histopathology relating to the new classification introduced in 2008 by the World Health Organisation (WHO) and treatment of PTLD.