Pre-transplant end-stage renal disease-related immune risk profile in kidney transplant recipients predicts post-transplant infections.

BACKGROUND: End-stage renal disease (ESRD) is associated with premature aging of the T-cell system. Nevertheless, the clinical significance of pre-transplant ESRD-related immune senescence is unknown. METHODS: We studied whether immune risk phenotype (IRP), a typical feature of immune senescence, may affect post-transplant infectious complications. A total of 486 patients were prospectively studied during the first year post transplant. IRP was defined as positive cytomegalovirus serology with at least 1 of the following criteria: CD4/CD8 ratio <1 and/or CD8 T-cell count >90th percentile. RESULTS: We found that 47 patients (9.7%) had pre-transplant IRP. IRP+ patients did not differ from IRP- patients for any clinical characteristics, but exhibited more pronounced immune senescence. Both opportunistic infections (43% vs. 6%, P < 0.001) and severe bacterial infection (SBI) (40% vs. 25%, P = 0.028) were more frequent in IRP(+) patients. In multivariate analysis, IRP was predictive of both opportunistic infection (hazard ratio [HR] 2.97 [95% confidence interval {CI} 1.53-5.76], P = 0.001), and SBI (HR 2.33 [95% CI 1.34-3.92], P = 0.008). Acute rejection rates were numerically much lower in IRP+ patients. A total of 418 patients (86%) had biological evaluation 1 year post transplant. Among 41 IRP+ patients, 35 (85%) remained IRP+ 1 year post transplant. CONCLUSION: Pre-transplant IRP is associated with an increased risk of post-transplant infection.

ATG-induced accelerated immune senescence: clinical implications in renal transplant recipients.

Persistent ATG-induced CD4(+) T cell lymphopenia is associated with serious clinical complications. We tested the hypothesis that ATG induces accelerated immune senescence in renal transplant recipients (RTR). Immune senescence biomarkers were analyzed at transplant and one-year later in 97 incident RTR -62 patients receiving ATG and 35 receiving anti-CD25 mAb (α-CD25). This consisted in: (i) thymic output; (ii) bone marrow renewal of CD34(+) hematopoietic progenitor cells (CD34(+) HPC) and lymphoid (l-HPC) and myeloid (m-HPC) progenitor ratio; (iii) T cell phenotype; and (iv) measurement of T cell relative telomere length (RTL) and telomerase activity (RTA). Clinical correlates were analyzed with a 3 year follow-up. Thymic output significantly decreased one-year posttransplant in ATG-treated patients. ATG was associated with a significant decrease in l-HPC/m-HPC ratio. Late stage differentiated CD57(+) /CD28(-) T cells increased in ATG-treated patients. One-year posttransplant T cell RTL and RTA were consequently lower in ATG-treated patients. ATG is associated with accelerated immune senescence. Increased frequency of late differentiated CD4(+) T cell frequency at transplantation tended to be predictive of a higher risk of subsequent opportunistic infections and of acute rejection only in ATG-treated patients but this needs confirmation. Considering pretransplant immune profile may help to select those patients who may benefit from ATG to prevent severe infections and acute rejection.

Subclinical Epstein-Barr virus viremia among adult renal transplant recipients: incidence and consequences.

The natural history and clinical significance of posttransplant Epstein-Barr virus (EBV) infection remain largely unknown. The aims of this study are to describe the incidence, risk factors and consequences of EBV infection after kidney transplantation. A total of 383 consecutive patients having received a kidney transplant between January 2002 and December 2010 were included. EBV polymerase chain reaction (PCR) was performed every 2 weeks for 3 months, and every 4 weeks for the next 9 months. A total of 155 of the 383 patients (40%) had at least one positive viremia during the first year posttransplant. The median time to viremia was day 31 posttransplant (14-329). A total of 73 (47%) had EBV viremia > 10(3) log and 23 (15%) had positive viremia for more than 6 months. EBV D+/R- patients (12/18 (67%) versus 143/365 (39%), p = 0.02) and those having received antithymocyte globulins (ATG) (54% vs. 35%; p<0.001) were more likely to develop EBV infection. EBV infection (hazard ratio [HR], 3.03; 95% confidence interval [CI], 1.72-8.29; p = 0.01) was associated with the occurrence of opportunistic infections. A positive EBV PCR during the first 6 months posttransplant was associated with graft loss (HR, 3.04; 95% CI, 1.36-6.79; p = 0.014). EBV reactivation is frequent after transplantation and reflects overimmunosuppression. Prospective studies should examine the association between EBV and graft loss.

Description of an outbreak of hemorrhagic fever with renal syndrome in the southern Jura Mountains, France, in 2021.

OBJECTIVE: The aim of our study was to describe the 2021 Hemorrhagic Fever with Renal Syndrome (HFRS) outbreak in the southern Jura Mountains. PATIENTS AND METHODS: We included all laboratory-confirmed cases of HFRS reported between April and September 2021 in the three local hospitals. RESULTS: A total of 90 patients were enrolled in the study: 73 hospitalized and 17 non-hospitalized patients. Transient myopia was only reported in non-hospitalized patients. Forty (44.4 %) patients underwent medical imaging before hantavirus diagnosis. Twenty-one patients (28.8 %) had a plasma creatinine level > 353.6 µmol/L, no patient developed severe metabolic disorder. Only one patient was dialyzed. A pacemaker was implanted before diagnosis of HFRS due to severe bradycardia in one patient. Sudden death was reported in one patient. CONCLUSION: This hantavirus epidemic led to numerous hospitalizations, one dialysis treatment, and one death. Early diagnosis by rapid test could avoid unnecessary investigations.

Influence of cyclooxygenase-2 (COX-2) gene promoter polymorphism -765 on graft loss after renal transplantation.

A G-->C polymorphism has been identified in the human cyclooxygenase-2 (COX-2) gene promoter at position -765 with C allele leading to a decreased promoter activity with low prostaglandin E2 (PGE2) production. PGE2 has strong immunomodulatory properties that could influence graft survival. We studied the association between this polymorphism and allograft failure in two independent cohorts of renal transplant recipients (RTRs) including a total of 603 patients. The functional effect of COX-2 gene promoter polymorphism was analyzed by measuring serum levels of PGE2. Median follow-up was 8.7 and 7.9 years for the first and second cohort, respectively. Analysis of 603 patients identified 20 CC (3.3%), 179 GC (29.7%) and 404 GG (67%) carriers. Patients with the GG genotype had significantly higher serum PGE2 concentrations than patients with the C allele. Carriers with a C allele have an independent increased risk of graft loss (hazard ratio (HR) 2.43 [95% CI 1.19-4.97], p = 0.015 for cohort 1; HR 1.72 [95% CI 0.99-3.77], p = 0.051 for cohort 2) compared to GG patients. COX-2 gene promoter polymorphism at position -765 (G-->C) is associated with a higher rate of graft loss in RTRs. Such findings may be used to influence immunosuppressive strategies and optimize patient management.

PRODIG (Prevention of new onset diabetes after transplantation by a short term treatment of Vildagliptin in the early renal post-transplant period) study: study protocol for a randomized controlled study.

BACKGROUND: Post-transplant diabetes is a frequent and serious complication of kidney transplantation. There is currently no treatment to prevent or delay the disease. Nevertheless, identification of risk factors make it possible to target a population at risk of developing de novo diabetes. We hypothesized that a short-term treatment with vildagliptin may prevent new onset diabetes after transplantation (NODAT) in high-risk patients. METHODS/DESIGN: This is a multicenter, double-blind, placebo-controlled randomized clinical trial. Patients undergoing first kidney transplantation will be included from ten French transplant centers. Included patients will be randomized (1:1) to receive either vildagliptin 100 or 50 mg/day (depending on glomerular filtration rate) during 2 months (the first dose being administered before entering the operating theatres) or placebo. Additional antidiabetic therapy could be administered according to glycemic control. The primary outcome is the proportion of diabetic patients 1 year after transplantation, defined as patients receiving a diabetic treatment, or having a fasting glucose above 7 mmol/l, and/or with an abnormal oral glucose tolerance test. Secondary outcomes include glycated hemoglobin, the occurrence of acute rejection, infection, graft loss and patient death at 3 months, 6 months, and 12 months after transplantation. Outcomes will be correlated to clinical and general characteristics of the patient, cardiovascular history, nephropathy, dialysis history, transplantation data, biological data, health-related quality of life, and the cost-effectiveness of prevention of diabetes with vildagliptin. DISCUSSION: We have scarce data on the pharmacological prevention of post-transplant diabetes. If our hypothesis is verified, our results will have a direct application in clinical practice and could limit diabetes-associated morbidity, reduce cardiovascular complications, increase quality of life of renal transplant patients, and consequently promote graft and patient survival. Our results may possibly serve for non-transplant patients carrying a high-risk of diabetes associated with other co-morbidities. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02849899 . Registered on 8 February 2016.

[Immune monitoring of kidney transplant recipients: can markers predictive of over-immunosuppression be identified?]. / Surveillance biologique des patients transplantés rénaux : vers une prévision des complications associées à l'immunosuppression ?

While the use of nonspecific immunosuppressive drugs has significantly reduced the incidence of acute graft rejection, the benefits of such therapies on chronic rejection and overall long-term graft survival are uncertain. Persistent excessive immunosuppression after immunosuppressive drug treatment is associated with long-term toxicity including increased incidence of cancers, severe infectious complications and metabolic diseases (for example, diabetes, atherosclerosis). One of our team's aims is to identify immunological factors that can predict such toxicities. We have previously demonstrated that CD4T cell cytopenia was correlated with high risk of cancers and infections as well as atherosclerosis in renal transplant recipients. Now, we are investigating the mechanisms involved in CD4T cell cytopenia. We are also exploring how inflammation and cells from the innate immunity influence the complications associated with kidney transplantation. This was performed through the analysis of gene polymorphism on TLR-4, NOD2/CARD15 receptors and IL-6 promoter and correlation with transplantation outcome. We already correlated IL-6 promoter gene polymorphism at position -174 with new-onset diabetes after transplantation in overweight patients. Identification of gene polymorphisms or factors associated with complications after transplantation may help physicians to determine high-risk recipient profiles and optimize pre- and post-transplantation treatment strategies.

Antithymocytes globulins: Time to revisit its use in kidney transplantation?

T cell depletion by polyclonal antithymocyte globulins (ATG) has been used for many years in both organ and hematopoietic cell transplantation as an induction and rejection therapy. Nevertheless, its use remains largely empirical and many clinical questions, such as the determination of an individualized dose, therapeutic relevance of nondepletive effects, or prediction of long-term effects, are still unresolved. This review evaluates the evidence-based knowledge and the uncertainties concerning ATG, and suggests perspectives and opportunities for modern use of this old drug.

[Immunosuppression and its use in kidney transplantation]. / Immunsuppression und Ergebnisse in der Nierentransplantation.

BACKGROUND: Current immunosuppressive protocols effectively prevent acute rejection of renal allografts. Extensive drug toxicity and the deleterious effects of long-term immunosuppression are associated with significant morbidity and mortality. OBJECTIVES: The purpose of this article is to provide an overview over modern immunosuppressants and their unwanted side effects and to discuss strategies for improved long-term transplant survival. METHODS: Review of the current topic-related literature and discussion of our own experience. RESULTS: The use of antibody induction together with an initial combination therapy of calcineurin inhibitors, mycophenolate and steroids is recommended and results in excellent early outcomes. Detrimental effects include an increased incidence of infections, malignomas, and cardiovascular diseases. Long-term transplant survival is impaired by extensive drug toxicity and the frequent development of donor specific antibodies. Reduction of overall cumulative exposure to immunosuppressants or the reduction of specific toxic drugs such as calcineurin inhibitors and steroids may improve long-term results. Alternative immunosuppressants like mTOR inhibitors and belatacept appear to be effective and safe but their long-term effects on patient and allograft survival needs to be established in clinical trials. CONCLUSIONS: Current immunosuppressants provide effective protection from renal allograft rejection. However, their use is complicated by serious side effects. In the future, development of novel immunosuppressants and optimization of minimization strategies may help to improve long-term success after kidney transplantation.