Immunosuppression and Results in Renal Transplantation

Physical exercise, the immune system and infection risk: implications for prehabilitation and rehabilitation for solid organ transplantation candidates and recipients

PURPOSE OF REVIEW

Solid organ transplantation recipients have an increased risk of infection, exacerbated by immunosuppressant medications that need to finely balance suppression of the immune system to prevent allograft rejection while avoiding over-suppression leading to infections and malignancy. Exercise modulates immune functions, with moderate-intensity activities particularly associated with enhanced antiviral immunity and reduced infection incidence. However, investigations of the effects of exercise and physical activity on immune function and infection risk posttransplantation are scarce. This review highlights areas where the relationship between exercise, immune function and infection risk has greatest potential for benefit for solid organ transplantation and therefore greatest need for investigation.

RECENT FINDINGS

Moderate and higher intensity exercise do not appear to cause adverse immunological effects in kidney transplantation recipients, although evidence from other organ transplantation is lacking. Evidence from healthy younger and older adults suggests that regular exercise can reduce risk of respiratory infections and latent herpesvirus reactivation and improves antibody responses to vaccination, which is of great importance for organ transplantation recipients.

SUMMARY

There is a strong need for research to investigate the role of exercise on immune function and infection risk in solid organ transplantation to improve both allograft survival and long-term health of the recipient.

Treatment Switches, Patterns, and Outcomes in Adult and Pediatric Patients Undergoing Kidney Transplantation Between 2000 and 2019: A Retrospective United States Claims Database Study

BACKGROUND

Immunosuppressive regimens are imperative for improving patient and graft survival following kidney transplantation in patients with kidney failure. However, real-world evidence regarding treatments and outcomes in these patients is scarce. We sought to describe the treatment switches (assessed by line of treatment [LOT]), patterns, and outcomes in patients who underwent kidney transplantation in the United States.

METHODS

This retrospective cohort study used claims data from the Optum Research Database in the United States. Adult and pediatric patients undergoing a kidney transplantation between January 1, 2000, and June 30, 2019, who had ≥1 year of baseline and follow-up visits and continuous enrollment in the Optum Research Database, were included.

RESULTS

Data from 7159 patients (6833, adult; 326, pediatric) were included. The mean age for adult and pediatric patients was 51.4 ± 12.8 years and 10.4 ± 5.1 years, respectively. The mean number of LOTs in patients with ≥1 LOT (n = 7004) was 4.1 ± 2.6 LOTs. Tacrolimus, antiproliferative agents, and prednisone were the most frequently prescribed immunosuppressants. No strong correlations were identified between switching from LOT1 to LOT2 and potential predictors of treatment switches. The proportion of patients who did not experience graft loss gradually decreased between month 3 and month 120 (72%-36%), driven by return to dialysis (66%-18%). A slower decrease was observed for graft rejection (98%-84%), retransplantation (98%-93%), and graft removal (98%-92%).

CONCLUSIONS

We described treatment switches, patterns, and outcomes in patients who underwent kidney transplantation in the United States. Future analytical studies are needed to test hypotheses derived from these observations.

Pharmacotherapeutic options for the prevention of kidney transplant rejection: the evidence to date

INTRODUCTION

Although early rejection episodes are successfully controlled, the problem of unrecognized production of de novo anti HLA antibodies and associated chronic rejection still persists.

AREAS COVERED

In addition to the standard induction and maintenance therapy, we present a couple of new drugs as induction (Alemtuzumab), CNI free protocol (Belatacept, Sirolimus, Everolimus), maintenance treatment in transplant patients with various type of malignancies (T cell targeted immunomodulators blocking the immune checkpoints CTLA-4, PD1/PDL1) and TMA (aHUS) -eculizimab, and IL6 receptor antagonists in antibody mediated rejection (AMR).

EXPERT OPINION

There are couple of issues still preventing improvement in kidney transplant long-term outcomes with current and anticipated future immunosuppression: patient more susceptible to infection and CNI nephrotoxicity in kidneys obtained from elderly donors, highly sensitized patients with limited chances to get appropriate kidney and a higher risk for late AMR. A lower rate of CMV/BK virus infections has been observed in everolimus treated patients. Belatacept use has been justified only in EBV seropositive kidney transplants due to the increased risk of PTLD. Eculizumab upon recurrence of aHUS is a sole cost-effective option. A new IL-6 blocking drug (clazakizumab/tocilizumab) is promising option for prevention/treatment of AMR. Clinical experience in tailoring immunosuppression for as long as possible graft and patient survival is inevitable.

Robot-assisted kidney transplantation: an update

Renal transplantation has become the gold-standard treatment for the majority of patients with established renal failure. Recent decades have seen significant progress in immunosuppressive therapies and advances in post-transplant management of recipients, resulting in improved graft and patient outcomes. However, the open technique of allograft implantation has stood the test of time, remaining largely unchanged. In a world where major advances in surgery have been facilitated by innovations in the fields of biotechnology and medical instrumentation, minimally invasive options have been introduced for the recipient undergoing kidney transplantation. In this review we present the evolution of minimally invasive kidney transplantation, with a specific focus on robot-assisted kidney transplant and the benefits it offers to specific patient groups. We also discuss the ethical concerns that must be addressed by transplant teams considering developing or referring to robotic programs.

The effect of genetic variations for interleukin-10 (IL-10) on the efficacy of immunosuppressive therapy in patients after kidney transplantation

Kidney transplantation is the target method of treating chronic kidney disorders. It improves the comfort of patient life by eliminating the need for repeated dialysis. The aim of the study was to examine the correlation between tacrolimus (TAC) dose and genetic variation for interleukin-10 (IL-10) and its effect on the therapeutic outcome. In addition, the correlations between the IL-10 polymorphism andthe clinical and the biochemical parameters of TAC patients were also analyzed. The study included 209 subjects after kidney transplantation, who received TAC every 12 and 24 h. Drug concentrations in blood, selected morphological and biochemical parameters, and the genetic variation of IL-10 (-1082A > G) which may affect immunosuppressant dosage and risk of acute graft rejection were analyzed. Genetic analyses were performed using real-time PCR. No significant correlations between the clinical and the biochemical parameters and IL-10-1082A > G polymorphism for patients receiving TAC after kidney transplantation were found. The analysis of the correlation between TAC dose and IL-10 genetic variation for the -1082A > G polymorphism revealed that patients with the AA genotype required lower immunosuppressive drug doses (AA: 3.54 ± 2.38 mg/day vs AG: 6.18 ± 5.10 mg/day, GG: 4.44 ± 3.01 mg/day). Furthermore, frequencies of the genotypes for the IL-10 -1082A > G polymorphism were characterized by a significantly higher frequency of the AA genotype among TAC 24 as compared to TAC 12 patients. The results of the study indicated that the IL-10 -1082A > G polymorphism may in fact influence the TAC dose. The biochemical parameters of the renal profile in relation to the IL-10 genetic variations were not indicative of higher risk of acute rejection after transplantation.

Fuzzy logic-based clinical decision support system for the evaluation of renal function in post-Transplant Patients

OBJECTIVES

In the context of the gradual development of artificial intelligence in health care, the clinical decision support systems (CDSS) play an increasing crucial role in improving the quality of the therapeutic and diagnostic efficiency in health care. The fuzzy logic (FL) provides an effective means for dealing with uncertainties in the health decision-making process; therefore, FL-based CDSS becomes a very powerful tool for data and knowledge management, being able to think like an expert clinician. This work proposes an FL-based CDSS for the evaluation of renal function in posttransplant patients.

METHOD

Based on the data provided by the Department of Nephrology of the University Hospital Federico II of Naples, a statistical sample is selected according to appropriate inclusion criteria. Four fuzzy inference systems are implemented monitoring the renal function by the level of proteinuria and the glomerular filtration rate (GFR).

RESULTS

The systems show an accuracy of more than 90% and the outputs are provided through easy to read graphics, so that physicians can intuitively monitor the patient's clinical status, with the objective to improve drugs dosage and reduce medication errors.

CONCLUSIONS

We propose that the CDSSs for the assessment and follow-up of kidney-transplanted patients built in this study are applicable to clinical practice.

Nontoxic concentration of ochratoxin A decreases the dosage of cyclosporine A to induce chronic nephropathy model via autophagy mediated by toll-like receptor 4

Cyclosporine A (CsA) extracted from the products of fungal fermentation is used to develop a chronic nephropathy model. However, it has numerous side effects. Ochratoxin A (OTA) is a mycotoxin that induces renal injury. We developed a chronic nephropathy model to lessen the side effects of CsA by administration of nontoxic dosage of OTA, and investigated the underlying mechanism. C57BL/10 wild-type mice, toll-like receptor 4 (TLR4)-/- mice, and HK-2 cells were used in this study. The nontoxic dosage (0.25 mg/kg, qod) of OTA could significantly decrease the dosage of CsA from 30 to 20 mg/kg per day, and combination of them induced chronic nephropathy model and alleviated the side effects of onefold CsA in vivo, including cardiotoxicity, hepatotoxicity, and immunosuppression. The nontoxic concentration (0.5 μg/ml) of OTA could significantly decrease the concentration of CsA from 10 to 6 μg/ml that induced cytotoxicity, oxidative stress, and nephrotoxicity in vitro. Nontoxic concentration of OTA and low dosage of CsA activated TLR4 and autophagy. These toxic effects induced by OTA and CsA could be reversed by knockdown of TLR4 and autophagy inhibitor 3-methyladenine in vitro. Furthermore, the renal injury and autophagy induced by OTA and CsA could be attenuated in TLR4-/- mice. It suggested that a chronic nephropathy model had been successfully developed by administration of nontoxic concentration of OTA and low dosage of CsA via TLR4-mediated autophagy. The side effects of current model were significantly lesser than those of the previous model induced by onefold CsA. It provided a new tool for exploring the pathogenesis and treatment of chronic kidney disease.

The impact of immunosuppression on postoperative graft function after graft-unrelated surgery: a retrospective controlled cohort study

Background

Physicians are faced with a growing number of patients after renal transplantation undergoing graft-unrelated surgery. So far, little is known about the postoperative restitution of graft function and the risk factors for a poor outcome.

Methods

One hundred one kidney transplant recipients undergoing graft-unrelated surgery between 2005 and 2015 were reviewed retrospectively. A risk analysis was performed and differences in creatinine, GFR and immunosuppressive treatment were evaluated. Additional, a comparison with a case-matched non-transplanted control group were performed.

Results

Preoperative creatinine averaged 1.88 mg / dl [0.62–5.22 mg / dl] and increased to 2.49 mg / dl [0.69–8.30 mg / dl] postoperatively. Acute kidney failure occurred in 18 patients and 14 patients had a permanent renal failure. Significant risk factors for the development of postoperative renal dysfunction were female gender, a preoperative creatinine above 2.0 mg / dl as well as a GFR below 40 ml / min and emergency surgery. Patients with tacrolimus and mycophenolate mofetil treatment showed a significant lower risk of renal dysfunction than patients with other immunosuppressants postoperatively. Contrary to that, the risk of patients with cyclosporine treatment was significantly increased. Transplanted patients showed a significantly increased rate of postoperative renal dysfunction.

Conclusions

The choice of immunosuppressant might have an impact on graft function and survival of kidney transplant recipients after graft-unrelated surgery. Further investigations are needed.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1358-2) contains supplementary material, which is available to authorized users.

Recent advances in kidney transplantation: a viewpoint from the Descartes advisory board

Transplantation medicine is a rapidly evolving field. Keeping afloat of the published literature to offer the best clinical care to our patients is a daunting task. As part of its educational mission, the Descartes advisory board identified seven topics in kidney transplantation where there has been substantial progresses over the last years: kidney allocation within Eurotransplant; kidney exchange strategies; kidney machine perfusion strategies; the changing landscape of anti-human leukocyte antigen (HLA) antibodies; the new immunosuppressive drugs in the pipeline; strategies for immunosuppression minimization; and the continuous enigma of focal segmental glomerular sclerosis recurrence after transplantation. Here, we have summarized the main knowledge and the main challenges of these seven topics with the aim to provide transplant professionals at large with key bullet points to successfully understand these new concepts.