KDIGO clinical practice guideline for the care of kidney transplant recipients

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.

Losing Much More Than a Transplant: A Qualitative Study of Kidney Transplant Recipients' Experiences of Graft Failure

Introduction

Kidney transplant recipients with graft failure are a growing cohort of patients who experience high morbidity and mortality. Limited evidence guides their care delivery and patient perspective to improve care processes is lacking. We conducted an in-depth exploration of how individuals experience graft failure, and the specific research question was: "What impact does the loss of an allograft have on their lives?"

Methods

We adopted an interpretive descriptive methodological design. Semistructured in-depth narrative interviews were conducted with adult recipients who had a history of ≥1 graft failure. Data were collected until data saturation was achieved and analyzed using an inductive and thematic approach.

Results

Our study included 23 participants from 6 provinces of Canada. The majority were on dialysis and not waitlisted for retransplantation (60.9%). Our thematic analysis identified that the lives of participants were impacted by a range of tangible and experiential losses that go beyond the loss of the transplant itself. The themes identified include loss of control, loss of coherence, loss of certainty, loss of hope, loss of quality of life, and loss of the transplant team. Although many perceived that graft failure was inevitable, the majority were unprepared. The confusion about eligibility for retransplantation appears to contribute to these experiences.

Conclusion

Individuals with graft failure experience complex mental and emotional challenges which may contribute to poor outcomes. The number of patients with graft failure globally is increasing and our findings can help guide practices aimed at supporting and guiding them toward self-management and adaptive coping.

Viral Infections in Pediatric Kidney Transplant Recipients: Effects on Graft Function, Risk Factors, and Patient Outcomes

OBJECTIVES

Viral infections are the leading cause of posttransplant morbidity and mortality. We aimed to determine the effect on graft function, the risk factors, the frequency, and types of viral infections and to evaluate the effect of viral infections on kidney and patient outcomes in pediatric kidney transplant patients.

MATERIALS AND METHODS

Records of children undergoing kidney transplant in our center during the period February 1, 2010, to December 31, 2023, were retrospectively evaluated. Demographic and laboratory data, kidney failure etiologies, donor types, immunosuppression treatments, acute rejection episodes, accompanying viral infections, glomerular filtration rate, and graft loss rate were analyzed.

RESULTS

Seventy-nine pediatric kidney transplant recipients were included in the study. The number of patients who experienced viral infections was 18 (23%). In total, 25 infection episodes were identified, with 6 (24%) attributed to cytomegalovirus infection, 8 (32%) to BK virus infection, 6 (24%) to varicella zoster virus infection (4 cases of shingles, 2 cases of chickenpox), 4 (16%) to parvovirus B19 infection, and 2 (8%) to COVID-19. Of 25 infection episodes, rejection episodes were observed in 11 cases (44%), and infections manifested after rejection in 8 cases (32%). Viral infections occurred an average of 15 months after rejection episodes. For 15 (60%) of the 25 infection episodes, the glomerular filtration rate was observed to be <60 mL/min/1.73 m2 during viral infection. Two patients succumbed to viral infections; 1 was due to COVID-19, and 1 was due to coinfection with parvovirus B19 and cytomegalovirus.

CONCLUSIONS

Our data emphasized the significant effect of viral infections on pediatric kidney transplant recipients. Early diagnosis and treatment in kidney transplant recipients are important, and clinicians should be alert.

Advancing immunosuppression in liver transplantation: A narrative review

Immunosuppression is essential to ensure recipient and graft survivals after liver transplantation (LT). However, our understanding and management of the immune system remain suboptimal. Current immunosuppressive therapy cannot selectively inhibit the graft-specific immune response and entails a significant risk of serious side effects, i.e., among others, de novo cancers, infections, cardiovascular events, renal failure, metabolic syndrome, and late graft fibrosis, with progressive loss of graft function. Pharmacological research, aimed to develop alternative immunosuppressive agents in LT, is behind other solid-organ transplantation subspecialties, and, therefore, the development of new compounds and strategies should get priority in LT. The research trajectories cover mechanisms to induce T-cell exhaustion, to inhibit co-stimulation, to mitigate non-antigen-specific inflammatory response, and, lastly, to minimize the development and action of donor-specific antibodies. Moreover, while cellular modulation techniques are complex, active research is underway to foster the action of T-regulatory cells, to induce tolerogenic dendritic cells, and to promote the function of B-regulatory cells. We herein discuss current lines of research in clinical immunosuppression, particularly focusing on possible applications in the LT setting.

Management of Early Post-Transplant Hyperglycemia by Dedicated Endocrine Care Improves Glycemic Outcomes

INTRODUCTION

Early post-transplant hyperglycemia (EPTH) is an independent risk factor for hospital readmissions, acute rejection, infections and developing post-transplant diabetes mellitus (PTDM). Close glycemic control is prudent in the early post-transplant period. The management of EPTH was evaluated among a cohort of kidney transplant recipients, who either received routine care (RC) or dedicated endocrine care (DEC).

METHODS

A retrospective analysis was conducted on kidney transplant recipients from 2019 to 2023. The impact of DEC on post-transplant glycemic control was investigated. Hospitalized patients receiving post-transplant insulin therapy were included. DEC involved at least twice-daily blood glucose (BG) assessment by an endocrinologist, while the RC received usual care. A mixed-model analysis was employed to assess differences in BG trajectories between DEC and RC over an eight-day period. Additionally, various glycemic control metrics were compared, including glucose variability, time-in-range for target BG, rates of hypoglycemia and response to hyperglycemia.

RESULTS

The cohort comprised 113 patients. In the DEC group, 91% had pre-transplant DM compared to 15% in the RC group (p < 0.001). Patients under DEC had higher baseline BG and glycated hemoglobin compared to those under RC (p < 0.001, for both). The DEC group displayed a lower trajectory of BG over time compared to the RC group (p = 0.002). Patients under DEC were more likely to receive insulin if BG measured above 200 mg/dL (66% vs. 46%) and displayed less below-range BG (<110 mg/dL) compared to those under RC (12.9% vs. 23.6%, p < 0.001).

CONCLUSIONS

Management of EPTH by DEC improves glycemic outcomes in renal transplant recipients.

Effects of two immunosuppression regimens on T-lymphocyte subsets in elderly kidney transplant recipients

Background

Despite the growing number of elderly kidney transplant (Ktx) recipients, few studies have examined the effects of immunosuppression on their lymphocyte profiles.

Methods

We evaluated the early conversion from mycophenolate sodium (MPS) to everolimus (EVL) after rabbit antithymocyte globulin (rATG) 2 mg/kg induction in elderly kidney recipients. Three groups of KTx patients were compared: (a) Young (n=20, 36 ± 7 y) receiving standard immunosuppression (Group A1) (prednisone, tacrolimus, and MPS), (b) Elderly (n=35, 65 ± 3 y) receiving standard immunosuppression (Group B1), and (c) Elderly (n=16, 65 ± 3 y) with early (mean 30 d) conversion from MPS to EVL (Group B2). Naive, memory, and regulatory peripheral blood TCD4+ lymphocytes were quantified at 0, 30, and 365 d.

Results

Results are reported as [mean(p25-p75)]. Young recipients had higher lymphocyte counts at baseline [2,100(1,630-2,400) vs. 1,310 (1,000-1,600)/mm3, p<0.0001] maintained higher counts within 365 d [1,850(1,590-2,120) vs. 1,130(460-1,325)/mm3, p=0.018 and vs. 1,410(805-1,895)/mm3, p=0.268]. Elderly recipients showed a decrease in lymphocytes within 30 d [1,310(1,000-1,600) vs. 910(700-1,198)/mm3, p=0.0012] with recovery within 365 d. The same pattern was observed in total lymphocytes and TCD4+ counts. Rabbit antithymocyte globulin induced a reduction in central memory T-cell percentages at 30 d in both young recipients [6.2(3.77-10.8) vs. 5.32(2.49-7.28)% of CD4+, p=0.036] and in elderly recipients [8.17(5.28-12.88) vs. 6.74(4.36-11)% of CD4+, p=0.05] on standard immunosuppression, returning to baseline at 365 d in elderly recipients but not in young recipients. Regulatory T CD39+ cells (Treg) percentages decreased at 30 d in elderly recipients [2.1(1.23-3.51) vs. 1.69(0.8-2.66)% of CD4+, p=0.0028] and in young recipients [1.29(0.45-1.85) vs. 0.84(0.18-1.82)% of CD4+, p=0.0038], returning to baseline at 365 d in elderly recipients [2.1(1.23-3.51) vs. 2.042(0.88-2.42)% of CD4+], but not in young recipients [1.29(0.45-1.85) vs. 0.86(0.7-1.34) % of CD4+]. The elderly everolimus conversion group did not show significant changes in cell profile over time or compared to elderly recipients with standard immunosuppression.

Conclusion

Aging favored the maintenance of Treg during the late transplantation period despite ongoing immunosuppression. Lymphocyte depletion due to rATG was more prominent in elderly recipients and affected memory subsets with a temporary reduction in central memory T cells. However, conversion to everolimus did not impact Treg profile. Reducing the dose of rATG in elderly recipients seems necessary for the expected lymphocyte changes with EVL to occur.

Clinical trial registration

nEverOld Trial, identifier NTC01631058.

Drug-drug interaction between diltiazem and tacrolimus in relation to CYP3A5 genotype status in Chinese pediatric patients with nephrotic range proteinuria: a retrospective study

Background

Tacrolimus is widely used to treat pediatric nephrotic range proteinuria (NRP). Diltiazem, a CYP3A4/5 inhibitor, is often administered with tacrolimus, affecting its pharmacokinetic profile. The impact of this combination on tacrolimus exposure, particularly in CYP3A5*3 genetic polymorphism, remains unclear in pediatric NRP patients. This study aimed to evaluate the effects of diltiazem on tacrolimus pharmacokinetics, focusing on the CYP3A5*3 polymorphism.

Methods

We conducted a retrospective clinical study involving pediatric NRP patients, divided into two groups: those receiving tacrolimus with diltiazem and those receiving tacrolimus alone. Propensity score matching (PSM) was used to balance the baseline characteristics between the groups. We compared daily dose-adjusted trough concentrations (C0/D) of tacrolimus in both the original and PSM cohorts. The influence of diltiazem on tacrolimus C0/D, stratified by CYP3A5*3 genetic polymorphism, was assessed in a self-controlled case series study.

Results

Before PSM, the tacrolimus C0/D in patients taking diltiazem was significantly higher compared to those with tacrolimus alone (75.84 vs. 56.86 ng/mL per mg/kg, P = 0.034). This finding persisted after PSM (75.84 vs. 46.93 ng/mL per mg/kg, P= 0.028). In the self-controlled case study, tacrolimus C0/D elevated about twofold (75.84 vs. 34.76 ng/mL per mg/kg, P < 0.001) after diltiazem administration. CYP3A5 expressers (CYP3A5*1/*1 and *1/*3) and CYP3A5 non-expressers (CYP3A5*3/*3) experienced a 1.8-fold and 1.3-fold increase in tacrolimus C0/D when combined with diltiazem, respectively.

Conclusion

Diltiazem significantly increased tacrolimus C0/D, with CYP3A5*3 expressers showing higher elevations than non-expressers among pediatric NRP patients. These findings highlight the importance of personalized tacrolimus therapy based on CYP3A5*3 genotypes in pediatric patients taking diltiazem.

Effect of CYP3A5*3, ABCC2 C-24T, and ABCC2 C3972T Genetic Polymorphisms on Direct Cost of Kidney Transplant Recipients

Introduction Genetic variations can influence how kidney transplant recipients (KTRs) respond to immunosuppressive drugs. However, limited resources necessitate a cost-benefit analysis of pharmacogenetic testing to determine its role in routine practice. This study investigated the cost-effectiveness of three genetic polymorphisms (CYP3A5*3, ABCC2 -24C>T, and ABCC2 3972C>T) in KTRs. Methods This was a multicenter, prospective observational cohort study that included patients on tacrolimus-mycophenolate-prednisolone treatment. Ethnically diverse adult KTRs who had undergone kidney transplantation between 2020 and 2021 and consented were enrolled in the study. Deoxyribonucleic acid (DNA) was extracted from the collected blood samples using a commercially available kit. CYP3A5*3, ABCC2 -24C>T, and ABCC2 3972C>T single nucleotide polymorphisms (SNPs) were determined by polymerase chain reaction (PCR). Results Data was analyzed from 39 KTRs with an average age of 32.2 ± 7.0 years. The median annual healthcare cost per patient was MYR 52,700 (laboratory tests and immunosuppressants being the highest expenses). Notably, the annual cost was significantly higher in patients with the CYP3A5*3 variant compared to the wildtype (p < 0.001). Furthermore, an incremental cost-effectiveness analysis revealed that carriers of the CYP3A5*1 wildtype allele, the ABCC2 -24C>T T variant allele, and the ABCC2 3972C>T T variant allele were associated with a more cost-effective approach to kidney transplantation management, potentially reducing the risk of graft rejection and acute tubular necrosis (ATN). Conclusion While these findings suggest potential cost benefits for specific genotypes, further research with larger and more diverse patient populations is necessary to definitively establish the role of pharmacogenetic testing in optimizing cost-effectiveness for KTRs.

Comparative Efficacy and Safety of Low-Dose Versus Standard-Dose Rabbit Antithymocyte Globulin Induction Strategy in Kidney Transplant Recipients: Insights From a Single-Center Experience in North India

Background Rabbit antithymocyte globulin (rATG) is frequently utilized as an induction therapy in kidney transplant recipients (KTRs). Full-dose rATG induction therapy (7-10 mg/kg) has been associated with increased morbidity. However, definitive data on the appropriate rATG dosage remains scarce. In this study, we evaluated the efficacy and tolerability of varying rATG doses in KTRs. Methodology A single-center, retrospective, observational study was conducted between 2009 and 2014 in a cohort of 208 KTRs who received rATG induction therapy. Patients included in the study had received two to three consecutive doses of rATG as part of their planned induction protocol. Participants were categorized into the following two groups based on the cumulative dosage of rATG received during induction therapy: group A received 2 or 2.5 mg/kg, while group B received ≥3 mg/kg. The five-year follow-up data were analyzed. Results A cumulative rATG dose of 2 or 2.5 mg/kg and ≥3 mg/kg was given to 122 and 86 patients, respectively. The incidence of delayed graft function (DGF), acute rejection episodes, total graft loss, death, and death-censored graft loss was 6.25%, 3.84%, 7.21%, 4.32%, and 2.88%, respectively. Two malignancies and 141 infectious complications were noted. There was no significant difference between the groups regarding DGF, total graft loss, death, death-censored graft loss, infectious complications, and incidence of acute rejection episodes. Deceased donor kidney transplantation was identified as a significant predictor of acute rejection episodes (odds ratio = 9.19, 95% confidence interval = 1.567-53.907; p = 0.014). Conclusions The dosage for rATG induction therapy for KTRs should be tailored based on immunological and other factors impacting graft survival, along with a comprehensive risk assessment for potential infectious complications. A cumulative dose of 2.0 or 2.5 mg/kg could be optimal, offering effective induction therapy in KTRs with excellent graft survival rates and potentially fewer infectious complications.

Comparative performance evaluation of random access and real-time PCR techniques in the diagnosis of BK virus infections in transplant patients

PURPOSE

The study aims to compare random-access NeuMoDx values with artus qPCR values to validate the accuracy of NeuMoDx as an alternative to qPCR and provide an equation to convert copies/ml to IU/ml measurements.

METHODS

A total of 95 samples, including 61 transplant patient samples (n = 23 urine, n = 38 plasma) as the study group, 28 BKPyV-free samples as the control group, and six quality control samples, were included. One-Way ANOVA, Pearson correlation, Bland-Altman, Passing-Bablok, Deming regression analyses were used for statistical evaluation.

RESULTS

Of 95 samples, 46 (48 %) were positive with NeuMoDx, while 40 (42 %) were positive with artus qPCR. Both techniques were statistically similar (p > 0.05). Deming correlation analysis (r = 0.9590), Passing Bablok and Bland Altman analyses demonstrated a strong correlation between NeuMoDx and artus values. The equation that provides the conversion between NeuMoDx and artus qPCR values was NeuMoDx= (1.12965 x artus qPCR) - 0.55016. BKPyV infections remain a concern for transplant patients globally, and effective new diagnostic methods are required.

CONCLUSIONS

Consistency between the results of NeuMoDx and qPCR confirms that NeuMoDx may be a valuable alternative for detecting BKPyV to prevent viral propagation. Our findings may allow converting copy/ml results to IU/ml for diagnosing and monitoring BKPyV infections in transplant patients.

Interaction between tacrolimus and calcium channel blockers based on CYP3A5 genotype in Chinese renal transplant recipients

Objective

To investigate the effect of calcium channel blockers (CCBs) on tacrolimus blood concentrations in renal transplant recipients with different CYP3A5 genotypes.

Methods

This retrospective cohort study included renal transplant recipients receiving tacrolimus-based immunosuppressive therapy with or without CCBs in combination. Patients were divided into combination and control groups based on whether or not they were combined with CCBs, and then further analyzed according to the type of CCBs (nifedipine/amlodipine/felodipine). Propensity score matching was conducted for the combination and the control groups using SPSS 22.0 software to reduce the impact of confounding factors. The effect of different CCBs on tacrolimus blood concentrations was evaluated, and subgroup analysis was performed according to the patients' CYP3A5 genotypes to explore the role of CYP3A5 genotypes in drug-drug interactions between tacrolimus and CCBs.

Results

A total of 164 patients combined with CCBs were included in the combination groups. After propensity score matching, 83 patients with nifedipine were matched 1:1 with the control group, 63 patients with felodipine were matched 1:2 with 126 controls, and 18 patients with amlodipine were matched 1:3 with 54 controls. Compared with the controls, the three CCBs increased the dose-adjusted trough concentration (C0/D) levels of tacrolimus by 41.61%-45.57% (P < 0.001). For both CYP3A5 expressers (CYP3A5*1*1 or CYP3A5*1*3) and non-expressers (CYP3A5*3*3), there were significant differences in tacrolimus C0/D between patients using felodipine/nifedipine and those without CCBs (P < 0.001). However, among CYP3A5 non-expressers, C0/D values of tacrolimus were significantly higher in patients combined with amlodipine compared to the controls (P = 0.001), while for CYP3A5 expressers, the difference in tacrolimus C0/D values between patients with amlodipine and without was not statistically significant (P = 0.065).

Conclusion

CCBs (felodipine/nifedipine/amlodipine) can affect tacrolimus blood concentration levels by inhibiting its metabolism. The CYP3A5 genotype may play a role in the drug interaction between tacrolimus and amlodipine. Therefore, genetic testing for tacrolimus and therapeutic drug monitoring are needed when renal transplant recipients are concurrently using CCBs.

HLA-DR/DQ eplet mismatch predicts de novo donor-specific antibody development in multi-ethnic Southeast Asian kidney transplant recipients on different immunosuppression regimens

Eplet mismatch has been recognized as a more precise strategy for determining HLA compatibility by analyzing donor-recipient HLA differences at the molecular level. However, predicting post-transplant alloimmunity using single-molecule eplet mismatch categories has not been validated in Asian cohorts. We examined a cohort of Southeast Asian kidney transplant recipients (n = 234) to evaluate HLA-DR/DQ eplet mismatch as a predictor of de novo donor-specific antibody (dnDSA) development. HLA-DR/DQ single-molecule eplet mismatch was quantified using HLA Matchmaker, and we utilized previously published HLA-DR/DQ eplet mismatch thresholds to categorize recipients into alloimmune risk groups and evaluate their association with dnDSA development. Recognizing that the predominance of cyclosporine use (71%) may alter published eplet mismatch thresholds derived from a largely tacrolimus-based (87%) cohort, we evaluated cohort-specific thresholds for HLA-DR/DQ single-molecule eplet mismatch categories. Recipient ethnicities included Chinese (65%), Malays (17%), Indians (14%), and others (4%). HLA-DR/DQ dnDSA developed in 29/234 (12%) recipients after a median follow-up of 5.4 years, including against isolated HLA-DR (n = 7), isolated HLA-DQ (n = 11), or both (n = 11). HLA-DR/DQ single-molecule eplet mismatch risk categories correlated with dnDSA-free survival (p = 0.001) with low-risk recipients having a dnDSA prevalence of 1% over 5 years. The cohort-specific alloimmune risk categories improved correlation with HLA-DR/DQ dnDSA-free survival and remained significant after adjusting for calcineurin inhibitor and anti-metabolite immunosuppression (p < 0.001). We validated the performance of single-molecule eplet mismatch categories as a prognostic biomarker for HLA-DR/DQ dnDSA development in a cohort of predominantly Asian kidney transplant recipients after adjusting for different immunosuppression regimens.

Extreme phenotype sampling and next generation sequencing to identify genetic variants associated with tacrolimus in African American kidney transplant recipients

African American (AA) kidney transplant recipients (KTRs) have poor outcomes, which may in-part be due to tacrolimus (TAC) sub-optimal immunosuppression. We previously determined the common genetic regulators of TAC pharmacokinetics in AAs which were CYP3A5 *3, *6, and *7. To identify low-frequency variants that impact TAC pharmacokinetics, we used extreme phenotype sampling and compared individuals with extreme high (n = 58) and low (n = 60) TAC troughs (N = 515 AA KTRs). Targeted next generation sequencing was conducted in these two groups. Median TAC troughs in the high group were 7.7 ng/ml compared with 6.3 ng/ml in the low group, despite lower daily doses of 5 versus 12 mg, respectively. Of 34,542 identified variants across 99 genes, 1406 variants were suggestively associated with TAC troughs in univariate models (p-value < 0.05), however none were significant after multiple testing correction. We suggest future studies investigate additional sources of TAC pharmacokinetic variability such as drug-drug-gene interactions and pharmacomicrobiome.

C4d, rather than C3d and C5b-9, Is Associated with Graft Loss in Recurrent IgA Deposition after Kidney Transplantation

INTRODUCTION

Recurrent IgA deposition is common after kidney transplantation. However, it is difficult to define whether IgA deposition is innocuous or contributes to organ damage. Next, although complement is known to be involved in the pathogenesis of IgA nephropathy (IgAN), its involvement has not been studied systematically in kidney transplant recipients (KTRs).

METHODS

KTRs with biopsy-proven native IgAN who underwent kidney biopsy after transplantation between 1995 and 2020 were included. Recurrent IgA deposition was defined as IgA deposit in the glomerulus. Staining of complement factors C4d, C3d, and C5b-9 was quantitatively evaluated using ImageScope.

RESULTS

Sixty-seven KTRs (85% male, 46 ± 13 years old, 12 [6-24] months after transplantation, 58% with indication biopsy) were included in the analyses. Of them, 25 (37%) had recurrent IgA deposition. There were no clinical differences between KTR with and without recurrent IgA deposition. C3d and C5b-9 were always present in biopsies with IgA deposition, while C4d was present in 48% of the biopsies. During a median follow-up of 9.6 [4.8-14] years, 18 (27%) KTRs developed death-censored graft failure. Recurrent IgA deposition was not associated with graft failure. Of the evaluated complement factors, only C4d staining was associated with graft failure in KTR with recurrent IgA deposition (hazard ratio = 2.55, 95% confidence interval = 1.07-6.03, p = 0.034).

CONCLUSIONS

Recurrent IgA deposition was not associated with graft failure in itself. C4d, when present, is strongly associated with graft loss in KTR with recurrent IgA deposition, suggesting a pathogenic role for the lectin pathway in recurrent IgAN.

Using 1/2 Descending Time in CEUS to Identify Renal Allograft Rejection

RATIONALE AND OBJECTIVES

This study investigates the potential of quantitative Contrast-Enhanced Ultrasound (CEUS) parameters to distinguish between graft dysfunction due to rejection and non-rejection in kidney transplant recipients.

METHODS

In this retrospective study, 50 kidney transplant patients who presented elevated serum creatinine or proteinuria were analyzed. They were categorized as rejection or non-rejection based on biopsy outcomes. These classifications were applied in both derivation (n = 33) and validation cohorts (n = 17). Prior to the biopsy, all patients underwent a CEUS. Quantitative parameters derived from the CEUS were further analyzed for their consistency and reliability. Additionally, the relationship between the Banff scores, a standard for diagnosing transplant rejections, and these CEUS parameters was explored.

RESULTS

Significant differences between rejection and non-rejection groups were observed in the CEUS parameters of derivation cohorts. Specifically, Peak Intensity (PI), 1/2 Descending Time (DT/2), Area Under Curve (AUC), and Mean Transit Time (MTT) stood out. Sensitivity and specificity for these parameters were 76.5% and 87.5% for PI, 76.5% and 81.2% for DT/2, 76.5% and 87.5% for AUC, and 68.8% and 94.1% for MTT, respectively. DT/2 and MTT showed superior interobserver agreement compared to PI and AUC. When extrapolating the cutoff values from the derivation cohort to the validation group, DT/2 and AUC exhibited optimal diagnostic precision with positive and negative predictive values being 91.7% vs. 100% and 100% vs. 85.7%, respectively. Additionally, DT/2 effectively differentiated between mild and moderate to severe microvascular inflammation, pivotal in diagnosing antibody-mediated renal transplant rejection.

CONCLUSION

DT/2 from CEUS parameters presents as a reliable tool to differentiate rejection from non-rejection causes in renal transplant dysfunction. Yet, large-scale, multi-center studies are essential for further validation.

Rehabilitation exercises for kidney transplant recipients in an organ transplant ward: a best practice implementation project

INTRODUCTION AND OBJECTIVES

Kidney transplantation is an effective treatment for end-stage kidney disease. Kidney transplant recipients (KTRs) are prone to experiencing reduced physical function, depression, fatigue, and lack of exercise motivation due to their sedentary lifestyle before surgery. Exercise is an effective intervention for KTRs, but it has not been properly implemented in many practice settings. This project aimed to promote evidence-based exercises as part of KTRs' rehabilitation to improve their health outcomes.

METHODS

This project was informed by the JBI Evidence Implementation Framework. The project was conducted in the organ transplant ward of a tertiary comprehensive hospital in Changsha, China. Based on a summary of best evidence, 12 audit criteria were developed for the baseline and follow-up audits involving 30 patients and 20 nursing staff. The JBI Practical Application of Clinical Evidence System (PACES) and Getting Research into Practice (GRiP) tool were used to identify barriers and facilitators and develop targeted strategies to improve issues.

RESULTS

Compared with the baseline audit, significant improvements were achieved in most of the criteria in the follow-up audit, with 9 of the 12 criteria reaching 100% compliance. Notably, the 6-minute walk distance test results were significantly higher, while the Self-Rating Depression Scale and Self-Rating Anxiety Scale scores were significantly lower ( p < 0.05).

CONCLUSIONS

This project demonstrates that evidence-based practice can improve the clinical practice of rehabilitation exercises for KTRs. The GRiP strategies proved to be extremely useful, notably, the formulation of a standardized rehabilitation exercise protocol, training, and enhancement of the exercising environment. Head nurses' leadership and decision-making also played an important role in the success of this project.

SPANISH ABSTRACT

http://links.lww.com/IJEBH/A180.

Long-Term Outcome after Early Mammalian Target of Rapamycin Inhibitor-Based Immunosuppression in Kidney Transplant Recipients

Background: The use of mammalian target of rapamycin inhibitors (mTORis) in kidney transplantation increases the risk of donor-specific human leukocyte antigen (HLA) antibody formation and rejection. Here, we investigated the long-term consequences of early mTORi treatment compared to calcineurin inhibitor (CNI) treatment. Methods: In this retrospective single-center analysis, key outcome parameters were compared between patients participating in randomized controlled immunosuppression trials between 1998 and 2011, with complete follow-up until 2018. The outcomes of eligible patients on a CNI-based regimen (n = 384) were compared with those of patients randomized to a CNI-free mTORi-based regimen (n = 81) and 76 patients randomized to a combination of CNI and mTORi treatments. All data were analyzed according to the intention-to-treat (ITT) principle. Results: Deviation from randomized immunosuppression for clinical reasons occurred significantly more often and much earlier in both mTORi-containing regimens than in the CNI treatment. Overall patient survival, graft survival, and death-censored graft survival did not differ between the treatment groups. Donor-specific HLA antibody formation and BPARs were significantly more common in both mTORi regimens than in the CNI-based immunosuppression. Conclusions: The tolerability and efficacy of the mTORi treatment in kidney graft recipients are inferior to those of CNI-based immunosuppression, while the long-term patient and graft survival rates were similar.

Clinical Impacts of Allograft Biopsy in Renal Transplant Recipients 10 Years or Longer After Transplantation

We aimed to investigate the clinical value of allograft biopsy performed long after renal transplantation. We retrospectively evaluated 99 allograft biopsies in recipients with transplantation vintages of 10 years or longer. Mixed-effects model showed that 1-year estimated glomerular filtration rate (eGFR) slopes after biopsy were significantly greater than those before biopsy [-3.13, -4.42 mL/min/1.73 m2/year, p = 0.01]. Renal biopsy changed the treatment strategies in more than half of the patients. Improvement in eGFR slopes was pronounced in 51 patients with treatment modification based on the biopsy results [2.27 (95% confidence interval (CI): 0.66, 3.89) mL/min/1.73 m2/year], whereas no improvement was observed in those without [0.33 (95% CI: -1.05, 1.71) mL/min/1.73 m2/year, Pinteraction = 0.001]. Among the treatment modifications, enhancement of immunosuppression (IS) led to the most remarkable improvement in eGFR slope. Patients with g scores ≥2 were more likely to receive IS enhancement than those with g scores = 0 [odds ratio; 15.0 (95% CI: 1.65, 136)]. Patients with active glomerulitis (g ≥ 1) without chronicity (cg ≤ 1) showed the most significant improvement in eGFR slope. Given the prevalence of active glomerulitis (g ≥ 1, 21%), which is responsive to treatment even long after transplantation, and the observed magnitude of eGFR slope improvement, renal biopsy can indeed improve allograft prognosis.

Systemic oncological therapy in breast cancer patients on dialysis

The advancement of renal replacement therapy has significantly enhanced the survival rates of patients with end-stage renal disease (ESRD) over time. However, this prolonged survival has also been associated with a higher likelihood of cancer diagnoses among these patients including breast cancer. Breast cancer treatment typically involves surgery, radiation, and systemic therapies, with approaches tailored to cancer type, stage, and patient preferences. However, renal replacement therapy complicates systemic therapy due to altered drug clearance and the necessity for dialysis sessions. This review emphasizes the need for optimized dosing and administration strategies for systemic breast cancer treatments in dialysis patients, aiming to ensure both efficacy and safety. Additionally, challenges in breast cancer screening and diagnosis in this population, including soft-tissue calcifications, are highlighted.

SGLT2 Inhibitors Correct Fluid Overload in Adult Kidney Transplant Recipients-A Prospective Observational Study

In this longitudinal observational study, we measured urinary glucose concentration, body composition and volume status (bioimpedance spectroscopy) and plasma renin and aldosterone concentrations in n = 22 kidney transplant recipients (KTRs) initiating on SGLT2I at baseline (BL), and after 1 week and 1, 3, and 6 months. Estimated glomerular filtration rate (eGFR) decreased by -2 mL/min/1.73 m2 (IQR -10-0) after 1 week and remained stable thereafter. Urinary glucose concentration was 10 (3-24) g/g creatinine after 1 week and correlated with eGFR (r2 = 0.273; p = 0.057). SGLT2I did not affect HbA1c, fasting blood glucose, body weight, fat or lean mass. SGLT2I decreased fluid overload dependent on baseline overhydration (OH, r2 = 0.54, p = 0.0003) without occurrence of dehydration. Plasma aldosterone increased at day 7, while plasma renin did not change significantly. In conclusion, SGLT2I corrected fluid overload in patients with elevated overhydration at baseline, while in euvolemic KTRs fluid status remained stable without reduction of body water below the reference range, thus promoting the safety of SGLT2I therapy in patients following kidney transplantation. Glucosuria, together with effects of SGLT2I on blood glucose control and body weight, is attenuated in KTRs dependent on eGFR.

Donor-Dependent Variations in Systemic Oxidative Stress and Their Association with One-Year Graft Outcomes in Kidney Transplantation

INTRODUCTION

Oxidative stress has been implicated in complications after kidney transplantation (KT), including delayed graft function (DGF) and rejection. However, its role in long-term posttransplant outcomes remains unclear.

METHODS

We investigated oxidative damage and antioxidant defense dynamics, and their impact on the graft outcomes, in 41 KT recipients categorized by type of donation over 12 months. Oxidative status was determined using OxyScore and AntioxyScore indexes, which comprise several circulating biomarkers of oxidative damage and antioxidant defense. Donor types included donation after brain death (DBD [61.0%]), donation after circulatory death (DCD [26.8%]), and living donation (LD [12.1%]).

RESULTS

There was an overall increase in oxidative damage early after transplantation, which was significantly higher in DCD as compared to DBD and LD recipients. The multivariate adjustment confirmed the independent association of OxyScore and type of deceased donation with DGF, donor kidney function, and induction therapy with antithymocyte globulin. There were no differences in terms of antioxidant defense. Lower oxidative damage at day 7 predicted better graft function at 1-year posttransplant only in DBD recipients.

CONCLUSION

DCD induced greater short-term oxidative damage after KT, whereas the early levels of oxidative damage were predictive of the graft function 1 year after KT among DBD recipients.

Positive Long-Term Outcome of Kidney Allocation via Acceptable Mismatch Program in Highly Sensitized Patients

Introduction

Eurotransplant established the acceptable mismatch (AM) program to facilitate timely kidney transplantations of highly sensitized patients, but long-term granular clinical and immunological outcomes regarding overall graft survival and de novo DSA (dnDSA) formation are still intensively researched. The right choice of induction therapy in patients with differing immunological risk is not conclusively determined, as well as the impact of human leukocyte antigen (HLA) epitope matching on dnDSA formation.

Methods

This monocentric, retrospective study analyzed 94 patients transplanted within the AM program between 2000 and 2019 compared to case-control matched cohorts of non- (PRA 0-5%; PRA-0) and intermediately sensitized (PRA 6-84%; PRA-6/84) patients transplanted through Eurotransplant Kidney Allocation System.

Results

Estimated 10-year overall graft survival between the PRA-0 and AM cohorts was similar, whereas PRA-6/84 was significantly disadvantageous compared to PRA-0. Estimated 10-year incidence of antibody-mediated rejection rates was significantly lower in the PRA-0 group compared to AM and PRA-6/84 groups. Compared to the AM group, estimated incidence of de novo donor-specific antibody (dnDSA) was significantly lower in PRA-0 patients, with no differences between the AM and PRA-6/84 cohorts. The PRA-6/84 cohort was the only subgroup in which interleukin-2 receptor antagonist (IL2RA) induction was associated with longer overall graft survival, patient survival, and graft survival compared to depleting induction (ATG or OKT3). Broad HLA-A, -B, -DR mismatches (mmABDR) and HLA epitope mismatches determined by Eplets and PIRCHE-II were predictive for dnDSA formation in the total cohort, and the AM subgroup.

Discussion

The high efforts expended on AM patients are justified to allow timely organ transplantation with acceptable risk profile and non-inferior outcomes. IL2RA induction in intermediately sensitized patients is associated with superior overall graft survival, patient survival, and graft survival compared to ATG/OKT3 induction, without negative effects on rejection episodes or dnDSA formation. In silico epitope matching might further help reduce dnDSA formation, particularly in high-risk AM patients.

A review of landmark studies on maintenance immunosuppressive regimens in kidney transplantation

Immunosuppressive medications play a pivotal role in kidney transplantation, and the calcineurin inhibitors (CNIs), including cyclosporine A (CsA) and tacrolimus (TAC), are considered as the backbone of maintenance immunosuppressive regimens. Since the introduction of CNIs in kidney transplantation, the incidence of acute rejection has decreased, and allograft survival has improved significantly. However, CNI nephrotoxicity has been a major concern, believed to heavily impact long-term allograft survival and function. To address this concern, several CNI-sparing regimens were developed and studied in randomized, controlled, clinical trials, aiming to reduce CNI exposure and preserve long-term allograft function. However, more recent information has revealed that CNI nephrotoxicity is not the primary cause of late allograft failure, and its histopathology is neither specific nor pathognomonic. In this review, we discuss the historical development of maintenance immunosuppressive regimens in kidney transplantation, covering the early era of transplantation, the CNI-sparing era, and the current era where the alloimmune response, rather than CNI nephrotoxicity, appears to be the major contributor to late allograft failure. Our goal is to provide a chronological overview of the development of maintenance immunosuppressive regimens and summarize the most recent information for clinicians caring for kidney transplant recipients (KTRs).

Nurse-led clinical activity in kidney transplantation care in Spain: A cross-sectional observational study

OBJECTIVES

To explore the presence of specialist outpatient nursing activity in care for kidney transplant recipients in Spain and to determine the level of competence development of this activity according to the Advanced Practice Nurse model.

DESIGN

Descriptive, cross-sectional study.

PARTICIPANTS AND MEASUREMENTS

All outpatient nurses specialising in renal transplantation in the 39 transplant hospitals in Spain were included. To fulfil the study objectives, an ad hoc questionnaire and the 'Advanced Practice Nurse Role Definition Instrument (IDREPA)' were administered to assess the nurses' level of competence development.

RESULTS

Of the facilities included in the study, 25 (64.1%) had posttransplant nursing activity, 13 (33.3%) had pretransplant nursing activity and 11 (28.2%) had nursing activity involving kidney donor candidates. Twenty-seven specialist nurse's offices were identified. The results of the IDREPA reflect the presence of advanced practice in the domains of 'expert care planning' and 'comprehensive care'. Three (11.1%) nurses met all criteria for advanced nursing practice.

CONCLUSION

The results on specialised outpatient nursing activity at the 39 transplantation facilities in Spain indicate a low presence of this type of activity, with an even lower presence of advanced practice nurses.

IMPLICATIONS FOR CLINICAL PRACTICE

Management teams should consider investing in the quality of care provided by advanced nurse practice to ensure that suitable treatment is provided and better clinical outcomes are obtained.

CYP3A5 Genotype-Dependent Drug-Drug Interaction Between Tacrolimus and Voriconazole in Chinese Kidney Transplant Patients

BACKGROUND

The effect of drug-drug interaction (DDI) between tacrolimus and voriconazole on the pharmacokinetics of tacrolimus in different CYP3A5 genotypes has not been reported in previous studies.

OBJECTIVE

The objective of this study was to investigate whether CYP3A5 genotype could influence tacrolimus-voriconazole DDI in Chinese kidney transplant patients.

METHODS

All kidney transplant patients were divided into combination and non-combination groups based on whether tacrolimus was combined with or without voriconazole. Each group was subdivided into CYP3A5 expresser (CYP3A5*1/*1 or CYP3A5*1/*3) and CYP3A5 nonexpresser (CYP3A5*3/*3). A retrospective analysis compared tacrolimus dose (D)-corrected trough concentrations (C0) (C0/D) between combination and non-combination groups, respectively. Tacrolimus C0/D was also compared between CYP3A5 expresser and nonexpresser in both groups.

RESULTS

The C0/D values of tacrolimus were significantly different between CYP3A5 expresser and nonexpresser in combination group (378.20 [219.38, 633.48] ng/mL/[mg/kg/d] vs 720.00 [595.35, 1681.50] ng/mL/[mg/kg/d], P = 0.0010). Either in CYP3A5 expresser or nonexpresser, we found a statistically significant difference in tacrolimus C0/D between combination and non-combination group (P < 0.0001). The increase in CYP3A5 nonexpresser was 1.38 times higher than that in CYP3A5 expresser (320.93% vs 232.19%).

CONCLUSION AND RELEVANCE

The median C0/D values were 90.38% higher in kidney transplant recipients with CYP3A5*3/*3 genotype than in those with CYP3A5*1/*1 or CYP3A5*1/*3 genotype when treated with both tacrolimus and voriconazole. A CYP3A5 genotype-dependent DDI was found between tacrolimus and voriconazole. Therefore, personalized therapy accounting for CYP3A5 genotype detection and therapeutic drug monitoring is necessary for kidney transplant patients when treating with tacrolimus and voriconazole.

Inhibition of interferon regulatory factor 4 orchestrates T cell dysfunction, extending mouse cardiac allograft survival

BACKGROUND

T cell dysfunction, which includes exhaustion, anergy, and senescence, is a distinct T cell differentiation state that occurs after antigen exposure. Although T cell dysfunction has been a cornerstone of cancer immunotherapy, its potential in transplant research, while not yet as extensively explored, is attracting growing interest. Interferon regulatory factor 4 (IRF4) has been shown to play a pivotal role in inducing T cell dysfunction.

METHODS

A novel ultra-low-dose combination of Trametinib and Rapamycin, targeting IRF4 inhibition, was employed to investigate T cell proliferation, apoptosis, cytokine secretion, expression of T-cell dysfunction-associated molecules, effects of MAPK and mammalian target of Rapamycin (mTOR) signaling pathways, and allograft survival in both in vitro and BALB/c to C57BL/6 mouse cardiac transplantation models.

RESULTS

In vitro, blockade of IRF4 in T cells effectively inhibited T cell proliferation, increased apoptosis, and significantly upregulated the expression of programmed cell death protein 1 (PD-1), Helios, CD160, and cytotoxic T lymphocyte-associated antigen (CTLA-4), markers of T cell dysfunction. Furthermore, it suppressed the secretion of pro-inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17. Combining ultra-low-dose Trametinib (0.1 mg·kg-1·day-1) and Rapamycin (0.1 mg·kg-1·day-1) demonstrably extended graft survival, with 4 out of 5 mice exceeding 100 days post-transplantation. Moreover, analysis of grafts at day 7 confirmed sustained IFN regulatory factor 4 (IRF4) inhibition, enhanced PD-1 expression, and suppressed IFN-γ secretion, reinforcing the in vivo efficacy of this IRF4-targeting approach. The combination of Trametinib and Rapamycin synergistically inhibited the MAPK and mTOR signaling network, leading to a more pronounced suppression of IRF4 expression.

CONCLUSIONS

Targeting IRF4, a key regulator of T cell dysfunction, presents a promising avenue for inducing transplant immune tolerance. In this study, we demonstrate that a novel ultra-low-dose combination of Trametinib and Rapamycin synergistically suppresses the MAPK and mTOR signaling network, leading to profound IRF4 inhibition, promoting allograft acceptance, and offering a potential new therapeutic strategy for improved transplant outcomes. However, further research is necessary to elucidate the underlying pharmacological mechanisms and facilitate translation to clinical practice.

Systematic Review and Meta-Analysis Provide no Guidance on Management of Asymptomatic Bacteriuria within the First Year after Kidney Transplantation

(1) Background: Urinary tract infections (UTIs) are among the most frequent complications in kidney transplant (KT) recipients. Asymptomatic bacteriuria (ASB) may be a risk factor for UTIs and graft rejection. We aimed to evaluate available evidence regarding the benefit of screening and treatment of ASB within the first year after KT. (2) Evidence acquisition: A systematic literature search was conducted in MEDLINE, the Cochrane Library CENTRAL and Embase. Inclusion criteria were manuscripts in English addressing the management of ASB after KT. The PICO questions concerned Patients (adults receiving a KT), Intervention (screening, diagnosis and treatment of ASB), Control (screening and no antibiotic treatment) and Outcome (UTIs, sepsis, kidney failure and death). (3) Evidence synthesis: The systematic review identified 151 studies, and 16 full-text articles were evaluated. Seven were excluded because they did not evaluate the effect of treatment of ASB. There was no evidence for a higher incidence of lower UTIs, acute pyelonephritis, graft loss, or mortality in patients not treated with antibiotics for ASB. Analysis of comparative non-randomized and observational studies did not provide supplementary evidence to guide clinical recommendations. We believe this lack of evidence is due to confounding risk factors that are not being considered in the stratification of study patients.

A novel FK506-loading mesoporous silica nanoparticle homing to lymph nodes for transplant rejection treatment

Tacrolimus (FK506) is an effective therapeutic for transplant rejection in clinical practice, primarily inhibiting rejection by suppressing the activation and proliferation of allogeneic T cells in the lymph nodes (LNs). However, conventional administration methods face challenges in directly delivering free FK506 to the LNs. In this study, we introduce a novel LN-targeted delivery system based on mesoporous silica nanoparticles (MSNs-FK506-MECA79). These particles were designed to selectively target high endothelial venules in LNs; this was achieved through surface modification with MECA79 antibodies. Their mean size and zeta potential were 201.18 ± 5.98 nm and - 16.12 ± 0.36 mV, respectively. Our findings showed that MSNs-FK506-MECA79 could accumulate in LNs and increase the local concentration of FK506 from 28.02 ± 7.71 ng/g to 123.81 ± 76.76 ng/g compared with the free FK506 treatment group. Subsequently, the therapeutic efficacy of MSNs-FK506-MECA79 was evaluated in a skin transplantation model. The treatment with MSNs-FK506-MECA79 could lead to a decrease in the infiltration of T cells in the grafts, a reduction in the grade of rejection, and a significant prolongation of survival. Consequently, this study presents a promising strategy for the active LN-targeted delivery of FK506 and improving the immunotherapeutic effects on transplant rejection.

Relevance of Tacrolimus Trough Concentration and Hepatitis E virus Genetic Changes in Kidney Transplant Recipients With Chronic Hepatitis E

Introduction

Hepatitis E virus (HEV) can cause chronic infection (≥3 months) and cirrhosis in immunocompromised patients, especially kidney transplant recipients. Low alanine aminotransferase (ALT) levels and high HEV intrahost diversity have previously been associated with evolution toward chronicity in these patients. We hypothesized that additional clinical and viral factors could be associated with the risk of chronic HEV infection.

Methods

We investigated a series of 27 kidney transplant recipients with HEV infection, including 20 patients with chronic hepatitis E.

Results

High tacrolimus trough concentration at diagnosis was the most relevant marker associated with chronic hepatitis E (9.2 vs. 6.4 ng/ml, P = 0.04). Most HEV genetic changes selected during HEV infection were compartmentalized between plasma and feces.

Conclusion

This compartmentalization highlights the diversity and complexity of HEV replication compartments. Tacrolimus trough concentration at diagnosis of HEV infection could allow an early identification of patients at high risk of chronic hepatitis E and guide treatment initiation.

A Multiplex Fluorescence of Loop Primer Upon Self-Dequenching Loop-Mediated Isothermal Amplification Assay for the Detection of Epstein-Barr Virus and Human Parvovirus B19 in Clinical Transplant Samples

Viral infections are major causes of mortality in solid-organ and hematopoietic stem cell transplant recipients. Epstein-Barr virus (EBV) and Parvovirus B19 (B19V) are among the common viral infections after transplantation and were recommended for increased screening in relevant guidelines. Therefore, the development of rapid, specific, and cost-effective diagnostic methods for EBV and B19V is of paramount importance. We applied Fluorescence of Loop Primer Upon Self-Dequenching Loop-mediated Isothermal Amplification (FLOS-LAMP) for the first time to develop a novel multiplex assay for the detection of EBV and B19V; the fluorophore attached to the probe are self-quenched in unbound state. After binding to the dumbbell-shaped DNA target, the fluorophore is dequenched, resulting in fluorescence development. The novel multiplex FLOS-LAMP assay was optimized by testing various ratios of primer sets. This novel assay, with great specificity, did not cross-react with the common virus. For the detection of EBV and B19V, the limits of detection could reach 969 and 798 copies/μL, respectively, and the assay could be completed within 25 min. Applying this novel assay to detect 200 clinical transplant individuals indicated that the novel assay had high specificity and good sensitivity. We developed multiplex FLOS-LAMP assay for the detection of EBV and B19V, which has the potential to become an important tool for clinical transplant patient screening.

Predictive value of triglyceride/glucose index for cardiac outcomes in non-diabetic renal transplant recipients

OBJECTIVES

Insulin resistance (IR) is associated with an increased risk of adverse cardiovascular outcomes. The triglyceride-glucose index (TyG index) is a reliable marker of IR. No study has examined the impact of the TyG index on major adverse cardiac and cerebrovascular events (MACCEs) in RTRs. Therefore, this study aimed to investigate the predictive value of the TyG index for MACCEs in RTRs.

MATERIALS AND METHODS

Non-diabetic patients undergoing renal transplantation were retrospectively enrolled. The patients were divided into two groups according to MACCE development. The cut-off value of the TyG index for MACCE was conducted.

RESULTS

The mean age of 522 patients was 41 (31-51) years, and 349 (66.9%) were male. During the 5.4-year follow-up, 84 (16%) MACCE were recorded. TyG index was significantly higher in the group that developed MACCE (p < 0,001). Cox regression analysis revealed that TyG index [HR: 3.297 (1.228-8.855), p = 0.018], left ventricle ejection fraction [HR: 0.934 (0.900-0.968), p < 0.001], cadaveric transplantation [HR: 8.886 (4.764-16.576), p < 0.001], graft survey [HR: 0.608 (0.542-0.682), p < 0.001)], and smoking [HR: 1.965 (1.117-3.456), p = 0.019] were independent predictors of MACCEs in nondiabetic RTRs.

CONCLUSION

TyG index is an independent predictor of MACCEs in non-diabetic RTRs. The widespread use of the TyG index may positively affect long-term treatment costs and survival.

The Predictors and Risk Factors of 2-Year Rejection in Renal Transplant Patients: A Multicenter Case-Control Study

INTRODUCTION

Kidney transplantation is a definitive treatment for end-stage renal disease. It is associated with improved life expectancy and quality of life. One of the most common complications following kidney transplantation is graft rejection. To our knowledge, no previous study has identified rejection risk factors in kidney transplant recipients in Saudi Arabia. Therefore, this study aimed to determine the specific risk factors of graft rejection.

METHODS

A multicenter case-control study was conducted at four transplant centers in Saudi Arabia. All adult patients who underwent a renal transplant between January 1, 2015 and December 31, 2021 were screened for eligibility. Included patients were categorized into two groups (cases and control) based on the occurrence of biopsy-proven rejection within 2 years. The primary outcome was to determine the risk factors for rejection within the 2 years of transplant. Exact matching was utilized using a 1:4 ratio based on patients' age, gender, and transplant year.

RESULTS

Out of 1,320 screened renal transplant recipients, 816 patients were included. The overall prevalence of 2-year rejection was 13.9%. In bivariate analysis, deceased donor status, the presence of donor-specific antibody (DSA), intraoperative hypotension, Pseudomonas aeruginosa, Candida, and any infection within 2 years were linked with an increased risk of 2-year rejection. However, in the logistic regression analysis, the presence of DSA was identified as a significant risk for 2-year rejection (adjusted OR: 2.68; 95% CI: 1.10, 6.49, p = 0.03). Furthermore, blood infection, infected with Pseudomonas aeruginosa or BK virus within 2 years of transplant, were associated with higher odds of 2-year rejection (adjusted OR: 3.10; 95% CI: 1.48, 6.48, p = 0.003, adjusted OR: 3.23; 95% CI: 0.87, 11.97, p = 0.08 and adjusted OR: 2.76; 95% CI: 0.89, 8.48, p = 0.07, respectively).

CONCLUSION

Our findings emphasize the need for appropriate prevention and management of infections following kidney transplantation to avoid more serious problems, such as rejection, which could significantly raise the likelihood of allograft failure and probably death. Further studies with larger sample sizes are needed to investigate the impact of serum chloride levels prior to transplant and intraoperative hypotension on the risk of graft rejection and failure.

Optimizing the kidney donor pool: transplanting donor kidneys after partial nephrectomy of masses or cysts

Background

A limiting factor in expanding the kidney donor pool is donor kidneys with renal tumors or cysts. Partial nephrectomy (PN) to remove these lesions prior to transplantation may help optimize organ usage without recurrence of malignancy or increased risk of complications.

Methods

We retrospectively analyzed all recipients of a living or deceased donor graft between February 2009 and October 2022 in which a PN was performed prior to transplant due to the presence of one or more concerning growths. Donor and recipient demographics, perioperative data, donor allograft pathology, and recipient outcomes were obtained.

Results

Thirty-six recipients received a graft in which a PN was performed to remove suspicious masses or cysts prior to transplant. Majority of pathologies turned out to be a simple renal cyst (65%), followed by renal cell carcinoma (15%), benign multilocular cystic renal neoplasm (7.5%), angiomyolipoma (5%), benign renal tissue (5%), and papillary adenoma (2.5%). No renal malignancy recurrences were observed during the study period (median follow-up: 67.2 months). Fourteen complications occurred among 11 patients (30.6% overall) during the first 6mo post-transplant. Mean eGFR (± standard error) at 36 months post-transplant was 51.9 ± 4.2 ml/min/1.73 m2 (N = 23). Three death-censored graft losses and four deaths with a functioning graft and were observed.

Conclusion

PN of renal grafts with suspicious looking masses or cysts is a safe option to optimize organ usage and decrease the kidney non-use rate, with no observed recurrence of malignancy or increased risk of complications.

The Impact of ABCC2 -24C>T Gene Polymorphism on Graft Survival in Kidney Transplant Recipients

Personalized medicine in kidney transplantation has the potential to improve outcomes and reduce complications. The aim of this study was to investigate the influence of single nucleotide polymorphisms in genes encoding metabolizing enzymes (CYP3A5) and transporters (ABCC2) on clinical outcomes (acute graft failure and/or acute tubular necrosis (ATN)) in kidney transplant recipients (KTR). This was a multicenter, retrospective cohort study where adult KTR who had undergone kidney transplantation between 2020 and 2021 and received tacrolimus-mycophenolate treatment were enrolled in the study. DNA was extracted from collected blood samples using a commercially available kit. CYP3A5*3, ABCC2 -24C>T and ABCC2 3972C>T SNP were determined by polymerase chain reaction. Of the total 39 patients included, nine (23.1%) KTR had an incidence of acute graft failure and/or ATN. A multiple logistic regression showed wildtype ABCC2 -24C>T C allele had a higher risk of developing acute graft rejection and/or ATN compared to the variant allele carriers (adjusted Odd Ratios [aOR]: 27.675, p = 0.038). Recipients who had delayed graft function (aOR: 49.214, p = 0.012) and a history of CMV infection (aOR: 18.097, p = 0.009) were at 49.2 and 18.1-times increased risk for acute graft failure and/or ATN, respectively. The large aOR was inevitable due to the small sample size and required cautious interpretation. This is the first study to determine the effect of the ABCC2 -24C>T genetic polymorphism on clinical outcomes in Malaysian KTR and forms the basis for further work on ABCC2 -24C>T effects in long-term KTR.

European Consensus on the Management of Sensitized Kidney Transplant Recipients: A Delphi Study

An increasing number of sensitized patients awaiting transplantation face limited options, leading to fatalities during dialysis and higher costs. The absence of established evidence highlights the need for collaborative consensus. Donor-specific antibodies (DSA)-triggered antibody-mediated rejection (AMR) significantly contributes to kidney graft failure, especially in sensitized patients. The European Society for Organ Transplantation (ESOT) launched the ENGAGE initiative, categorizing sensitized candidates by AMR risk to improve patient care. A systematic review assessed induction and maintenance regimens as well as antibody removal strategies, with statements subjected to the Delphi methodology. A Likert-scale survey was distributed to 53 European experts (Nephrologists, Transplant surgeons and Immunologists) with experience in kidney transplant recipient care. A rate ≥75% with the same answer was considered consensus. Consensus was achieved in 95.3% of statements. While most recommendations aligned, two statements related to complement inhibitors for AMR prophylaxis lacked consensus. The ENGAGE consensus presents contemporary recommendations for desensitization and immunomodulation strategies, grounded in predefined risk categories. The adoption of tailored, patient-specific measures is anticipated to streamline the care of sensitized recipients undergoing renal allografts. While this approach holds the promise of enhancing transplant accessibility and fostering long-term success in transplantation outcomes, its efficacy will need to be assessed through dedicated studies.

JC Virus in Kidney Transplant Population: Are We Cautious Enough?

The John Cunningham virus (JCV) is a polyomavirus that usually infects people at a young age and does not cause any symptoms in immunocompetent individuals. However, in immunocompromised individuals, such as kidney transplant recipients, JCV can cause severe and potentially fatal disease. Unfortunately, JCV has not been researched as extensively as the BK virus and is not mentioned in relevant kidney transplant guidelines. This lack of attention to JCV can lead to less consideration in kidney transplant patients' care. Surveillance using locally available diagnostic methods is of the utmost importance. The presence of JCV can be diagnosed with urine decoy cells, viruria, or viremia verified by the PCR method. A low threshold for considering JCV as a possible cause of any neurological or renal dysfunction in kidney transplant recipients must be maintained. In such cases, kidney and brain biopsy are indicated. Maintaining the appropriate immunosuppression while avoiding over-immunosuppression to prevent JCV disease is crucial, and the approach should be individual, according to overall immunological risk. We hypothesize that the presence of the JCV can indicate overt immunosuppression and identify kidney transplant recipients more prone to opportunistic infections and diseases, including some malignancies. To explore that, future observational studies are needed.

In Vitro Profiling of Commonly Used Post-transplant Immunosuppressants Reveals Distinct Impact on Antiviral T-cell Immunity Towards CMV

Infectious complications, including widespread human cytomegalovirus (CMV) disease, frequently occur after hematopoietic stem cell and solid organ transplantation due to immunosuppressive treatment causing impairment of T-cell immunity. Therefore, in-depth analysis of the impact of immunosuppressants on antiviral T cells is needed. We analyzed the impact of mTOR inhibitors sirolimus (SIR/S) and everolimus (EVR/E), calcineurin inhibitor tacrolimus (TAC/T), purine synthesis inhibitor mycophenolic acid (MPA/M), glucocorticoid prednisolone (PRE/P) and common double (T+S/E/M/P) and triple (T+S/E/M+P) combinations on antiviral T-cell functionality. T-cell activation and effector molecule production upon antigenic stimulation was impaired in presence of T+P and triple combinations. SIR, EVR and MPA exclusively inhibited T-cell proliferation, TAC inhibited activation and cytokine production and PRE inhibited various aspects of T-cell functionality including cytotoxicity. This was reflected in an in vitro infection model, where elimination of CMV-infected human fibroblasts by CMV-specific T cells was reduced in presence of PRE and all triple combinations. CMV-specific memory T cells were inhibited by TAC and PRE, which was also reflected with double (T+P) and triple combinations. EBV- and SARS-CoV-2-specific T cells were similarly affected. These results highlight the need to optimize immune monitoring to identify patients who may benefit from individually tailored immunosuppression.

Effect of Different Induction Immunosuppression on the Incidence of Infectious Complications after Kidney Transplantation-Single Center Study

Background/Objectives: Potent immunosuppression lowers the incidence of acute graft rejection but increases the risk of infections. In order to decrease either infectious complications or acute rejection, it is necessary to identify risk groups of patients profiting from personalized induction immunosuppressive treatment. The aim of our analysis was to find whether there were higher incidences of infectious complications after kidney transplantation (KT) in groups with different induction immunosuppressive treatment and also to find independent risk factors for recurrent infections. Materials: We retrospectively evaluated all patients with induction treatment with basiliximab after kidney transplantation from 2014 to 2019 at our center relative to age- and sex-matched controls of patients with thymoglobulin induction immunosuppression. Results: Our study consisted of two groups: basiliximab (39) and thymoglobulin (39). In the thymoglobulin group we observed an increased incidence of recurrent infection in every observed interval; however, acute rejection was seen more often in the basiliximab group. A history of respiratory diseases and thrombocytopenia were identified as independent risk factors for recurrent bacterial infections from the first to sixth month after KT. Decreased eGFR from the first month, infections caused by multi-drug-resistant bacteria, and severe infections (reflected by the need for hospitalization) were identified as independent risk factors for recurrent bacterial infections from the first to the twelfth month after KT. Conclusions: We found that in the group of patients with thymoglobulin induction immunosuppressive treatment, infectious complications occurred significantly more often during the entire monitored period with decreased incidence of acute humoral and cellular rejection occurred more often.

Investigating the Impact of AI on Shared Decision-Making in Post-Kidney Transplant Care (PRIMA-AI): Protocol for a Randomized Controlled Trial

BACKGROUND

Patients after kidney transplantation eventually face the risk of graft loss with the concomitant need for dialysis or retransplantation. Choosing the right kidney replacement therapy after graft loss is an important preference-sensitive decision for kidney transplant recipients. However, the rate of conversations about treatment options after kidney graft loss has been shown to be as low as 13% in previous studies. It is unknown whether the implementation of artificial intelligence (AI)-based risk prediction models can increase the number of conversations about treatment options after graft loss and how this might influence the associated shared decision-making (SDM).

OBJECTIVE

This study aims to explore the impact of AI-based risk prediction for the risk of graft loss on the frequency of conversations about the treatment options after graft loss, as well as the associated SDM process.

METHODS

This is a 2-year, prospective, randomized, 2-armed, parallel-group, single-center trial in a German kidney transplant center. All patients will receive the same routine post-kidney transplant care that usually includes follow-up visits every 3 months at the kidney transplant center. For patients in the intervention arm, physicians will be assisted by a validated and previously published AI-based risk prediction system that estimates the risk for graft loss in the next year, starting from 3 months after randomization until 24 months after randomization. The study population will consist of 122 kidney transplant recipients >12 months after transplantation, who are at least 18 years of age, are able to communicate in German, and have an estimated glomerular filtration rate <30 mL/min/1.73 m2. Patients with multi-organ transplantation, or who are not able to communicate in German, as well as underage patients, cannot participate. For the primary end point, the proportion of patients who have had a conversation about their treatment options after graft loss is compared at 12 months after randomization. Additionally, 2 different assessment tools for SDM, the CollaboRATE mean score and the Control Preference Scale, are compared between the 2 groups at 12 months and 24 months after randomization. Furthermore, recordings of patient-physician conversations, as well as semistructured interviews with patients, support persons, and physicians, are performed to support the quantitative results.

RESULTS

The enrollment for the study is ongoing. The first results are expected to be submitted for publication in 2025.

CONCLUSIONS

This is the first study to examine the influence of AI-based risk prediction on physician-patient interaction in the context of kidney transplantation. We use a mixed methods approach by combining a randomized design with a simple quantitative end point (frequency of conversations), different quantitative measurements for SDM, and several qualitative research methods (eg, records of physician-patient conversations and semistructured interviews) to examine the implementation of AI-based risk prediction in the clinic.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06056518; https://clinicaltrials.gov/study/NCT06056518.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/54857.

Effects of Antithymocyte Globulin, Basiliximab, and Induction-Free Treatment in Living Donor Kidney Transplant Recipients on Tacrolimus-Based Immunosuppression

OBJECTIVES

Induction treatment in renal transplant is associated with better graft survival. However, intensified immunosuppression is known to cause unwanted side effects such as infection and malignancy. Furthermore, the effects of the routine use of immunosuppressants in low-risk kidney transplant recipients are still not clear. In this study, we assessed the first-year safety and efficacy of induction treatment.

MATERIALS AND METHODS

We examined first living donor kidney transplant patients who were on tacrolimus based immunosuppression therapy. We formed 3 groups according to the induction status: antithymocyte globulin induction, basiliximab induction, and no induction. We collected outcome data on delayed graft function, graft loss, creatinine levels, estimated glomerular filtration rates, acute rejection episodes, hospitalization episodes, and infection episodes, including cytomegalovirus infection and bacterial infections.

RESULTS

We examined a total of 126 patients (age 35 ± 12 years; 65% male). Of them, 25 received antithymocyte globulin, 52 received basiliximab, and 49 did notreceive any induction treatment. We did not observe any statistically significant difference among the 3 groups in terms of acute rejection episodes, delayed graft function, and first-year graft loss. The estimated glomerular filtration rates were similar among the groups. Overall bacterial infectious complications and cytomegalovirus infection showed similar prevalence among all groups. Hospitalization was less common in the induction-free group.

CONCLUSIONS

In low-risk patients, induction-free regimens could be associated with a better safety profile without compromising graft survival. Therefore, induction treatment may be disregarded in first living donor transplant patients who receive tacrolimusbased triple immunosuppression treatment.

Immunosuppressant Medications in Pregnancy

Pregnant patients are often on immunosuppressant medications, most commonly to manage transplantation or autoimmune disorders. Most immunosuppressant agents, including tacrolimus, corticosteroids, azathioprine, and calcineurin inhibitors, are safe during pregnancy and lactation. However, mycophenolic acid is associated with higher risks of birth defects and should be avoided in pregnancy. Tacrolimus, the commonly used drug in transplantation medicine and autoimmune disorders, requires monitoring of serum levels for dose adjustment, particularly during pregnancy. Although no pregnancy-specific therapeutic range exists, the general target range is 5-15 ng/mL, and pregnant patients may require higher doses to achieve therapeutic levels. Adherence to prescribed immunosuppressive regimens is crucial to prevent graft rejection and autoimmune disorder flare-ups. This review aims to provide essential information about the use of immunosuppressant medications in pregnant individuals. With a rising number of pregnant patients undergoing organ transplantations or having autoimmune disorders, it is important to understand the implications of the use of these medications during pregnancy.

Post-Transplant Glomerulonephritis: Challenges and Solutions

Glomeruli can be damaged in several conditions after kidney transplantation, with a potential impact on the graft function and survival. Primary glomerulonephritis, a group of glomerular immunological damage that results in variable histological patterns and clinical phenotypes, can occur in kidney transplant recipients as a recurrent or de novo condition. Specific immunologic conditions associated with kidney transplantation, such as acute rejection episodes, can act as an additional trigger after transplantation, impacting the incidence of these glomerulopathies. The post-transplant GN recurrence ranges from 3% to 15%, varying according to the GN subtype and post-transplant time, mainly occurring after 3-5 years of kidney transplantation. Advances in the knowledge of glomerulonephritis pathophysiology have provided new approaches to pre-transplant risk evaluation and post-transplant monitoring. Glomeruli can be affected by several systemic viral infections, such as human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), cytomegalovirus (CMV), and BK virus. The diagnosis of these infections, as well as the identification of possible complications associated with them, are important to minimize the negative impacts of these conditions on kidney transplant recipients' outcomes.

Adequacy to immunosuppression management guidelines in kidney transplant recipients with severe COVID-19 pneumonia: a practice survey

Introduction

Coronavirus disease 2019 (COVID-19) poses an important risk of morbidity and of mortality, in patients after solid organ transplantation. Recommendations have been issued by various transplantation societies at the national and European level to manage the immunosuppressive (IS) regimen upon admission to intensive care unit (ICU).

Method

The aim of this study was to evaluate the adequacy of IS regimen minimization strategy in kidney transplant recipients hospitalized in an ICU for severe COVID-19, in relation to the issued recommendations.

Results

The immunosuppressive therapy was minimized in all patients, with respectively 63% and 59% of the patients meeting the local and european recommendations upon admission. During ICU stay, IS was further tapered leading to 85% (local) and 78% (european) adequacy, relative to the guidelines. The most frequent deviation was the lack of complete withdrawal of mycophenolic acid (22%). Nevertheless, the adequacy/inadequacy status was not associated to the ICU- or one-year-mortality.

Discussion

In this single-center cohort, the only variable associated with a reduction in mortality was vaccination, emphasizing that the key issue is immunization prior to infection, not restoration of immunity during ICU stay.

Increased levels of a mycophenolic acid metabolite in patients with kidney failure negatively affect cardiomyocyte health

Chronic kidney disease (CKD) significantly increases cardiovascular risk and mortality, and the accumulation of uremic toxins in the circulation upon kidney failure contributes to this increased risk. We thus performed a screening for potential novel mediators of reduced cardiovascular health starting from dialysate obtained after hemodialysis of patients with CKD. The dialysate was gradually fractionated to increased purity using orthogonal chromatography steps, with each fraction screened for a potential negative impact on the metabolic activity of cardiomyocytes using a high-throughput MTT-assay, until ultimately a highly purified fraction with strong effects on cardiomyocyte health was retained. Mass spectrometry and nuclear magnetic resonance identified the metabolite mycophenolic acid-β-glucuronide (MPA-G) as a responsible substance. MPA-G is the main metabolite from the immunosuppressive agent MPA that is supplied in the form of mycophenolate mofetil (MMF) to patients in preparation for and after transplantation or for treatment of autoimmune and non-transplant kidney diseases. The adverse effect of MPA-G on cardiomyocytes was confirmed in vitro, reducing the overall metabolic activity and cellular respiration while increasing mitochondrial reactive oxygen species production in cardiomyocytes at concentrations detected in MMF-treated patients with failing kidney function. This study draws attention to the potential adverse effects of long-term high MMF dosing, specifically in patients with severely reduced kidney function already displaying a highly increased cardiovascular risk.

Impact of Immunosenescence in Older Kidney Transplant Recipients: Associated Clinical Outcomes and Possible Risk Stratification for Immunosuppression Reduction

The number of older individuals receiving a kidney transplant as replacement therapy has significantly increased in the past decades and this increase is expected to continue. Older patients have a lower rate of acute rejection but an increased incidence of death with a functioning graft. Several factors, including an increased incidence of infections, post-transplant malignancy and cardiovascular comorbidity and mortality, contribute to this increased risk. Notwithstanding, kidney transplantation is still the best form of kidney replacement therapy in all patients with chronic kidney disease, including in older individuals. The best form of immunosuppression and the optimal dose of these medications in older recipients remains a topic of discussion. Pharmacological studies have usually excluded older patients and when included, patients were highly selected and their numbers insignificant to draw a reasonable conclusion. The reduced incidence of acute rejection in older recipients has largely been attributed to immunosenescence. Immunosenescence refers to the aging of the innate and adaptive immunity, accumulating in phenotypic and functional changes. These changes influences the response of the immune system to new challenges. In older individuals, immunosenescence is associated with increased susceptibility to infectious pathogens, a decreased response after vaccinations, increased risk of malignancies and cardiovascular morbidity and mortality. Chronic kidney disease is associated with premature immunosenescent changes, and these are independent of aging. The immunosenescent state is associated with low-grade sterile inflammation termed inflammaging. This chronic low-grade inflammation triggers a compensatory immunosuppressive state to avoid further tissue damage, leaving older individuals with chronic kidney disease in an immune-impaired state before kidney transplantation. Immunosuppression after transplantation may further enhance progression of this immunosenescent state. This review covers the role of immunosenescence in older kidney transplant recipients and it details present knowledge of the changes in chronic kidney disease and after transplantation. The impact of immunosuppression on the progression and complications of an immunosenescent state are discussed, and the future direction of a possible clinical implementation of immunosenescence to individualize/reduce immunosuppression in older recipients is laid out.

Perioperative Characteristics and Outcomes of Fontan Versus Non-Fontan Patients Undergoing Combined Heart-Liver Transplantation: A Retrospective Cohort Study

OBJECTIVES

Combined heart-liver transplantation (CHLT) is becoming increasingly frequent as a maturing population of patients with Fontan-palliated congenital heart disease develop advanced liver fibrosis or cirrhosis. The authors present their experience with CHLT for congenital and noncongenital indications, and identify characteristics associated with poor outcomes that may guide intervention in high-risk patients.

DESIGN

This was a single-center retrospective cohort study.

SETTING

This study was conducted at Vanderbilt University Medical Center in Nashville, Tennessee.

PARTICIPANTS

The study included 16 consecutive adult recipients of CHLT at the authors' institution between April 2017 and February 2022.

INTERVENTIONS

Eleven patients underwent transplantation for Fontan indications, and 5 were transplanted for non-Fontan indications.

MEASUREMENTS AND MAIN RESULTS

Compared with non-Fontan patients, Fontan recipients had longer cardiopulmonary bypass duration (199 v 119 minutes, p =m0.002), operative times (786 v 599 minutes, p = 0.01), and larger blood product transfusions (15.4 v 6.3 L, p = 0.18). Six of 16 patients required extracorporeal membrane oxygenation (ECMO), of whom 4 were Fontan patients who subsequently died. Patients who required ECMO had lower 5-hour lactate clearance (0.0 v 3.5 mmol/L, p = 0.001), higher number of vasoactive infusions, lower pulmonary artery pulsatility indices (0.58 v 1.77, p = 0.03), and higher peak inspiratory pressures (28.0 v 18.5 mmHg, p = 0.01) after liver reperfusion.

CONCLUSIONS

Combined heart-liver transplantation in patients with Fontan-associated end-organ disease is particularly challenging and associated with higher recipient morbidity compared with non-Fontan-related CHLT. Early hemodynamic intervention for signs of ventricular dysfunction may improve outcomes in this growing high-risk population.

Beyond the First Year: Epidemiology and Management of Late-Onset Opportunistic Infections After Kidney Transplantation

Late opportunistic infections (OI) occurring beyond the first year after kidney transplantation (KT) are poorly described and not targeted by prophylactic strategies. We performed a ten-year retrospective monocentric cohort study describing epidemiology, risk factors and impact of late OI occurring 1 year after KT. We included clinically symptomatic OI requiring treatment besides BK virus nephropathy. Control groups included early OI occurring in the first year after KT, and KT recipients without OI since KT and alive with a functional allograft at 1 year. Among 1066 KT recipients, 185 (19.4%) presented a first episode of OI 21.0 (8.0-45.0) months after KT: 120 late OI (64.9%) and 65 early OI (35.1%). Late OI were mainly viral (N = 83, 69.2%), mostly herpes zoster (HZ) (N = 36, 43.4%). Pneumocystis represented most late fungal infections (N = 12/25, 48%). Compared to early OI, we reported more pneumocystis (p = 0.002) and less invasive aspergillosis (p = 0.01) among late OI. Patients with late OI were significatively younger at KT (54.0 ± 13.3 vs. 60.2 ± 14.3 years, p = 0.05). Patient and allograft survival rates between late OI and control groups were similar. Only age was independently associated with mortality. While late OI were not associated with higher mortality or graft loss, implementing prophylactic strategies might prevent such infections.

Incidence of De Novo Post-Transplant Malignancies in Thai Adult Kidney Transplant Recipients: A Single-Center, Population-Controlled, Retrospective Cohort Study at the Highest Volume Kidney Transplant Center in Thailand

Kidney transplant recipients (KTRs) are at increased risk of developing de novo post-transplant malignancies (PTMs), with regional differences in types with excess risk compared to the general population. A single-center, population-controlled, retrospective cohort study was conducted at a tertiary care center in Thailand among all adults who underwent their first kidney transplant from 1986 to 2018. Standardized incidence ratios (SIRs) of malignancy by age, sex, and place of residence were obtained using data from the National Cancer Registry of Thailand as population control. There were 2,024 KTRs [mean age, 42.4 years (SD 11.4); female patients, 38.6%] during 16,495 person-years at risk. Of these, 125 patients (6.2%) developed 133 de novo PTMs. The SIR for all PTMs was 3.85 (95% CI 3.22, 4.56), and for pooled solid and hematologic PTMs, it was 3.32 (95% CI 2.73, 3.99). Urothelial malignancies had the largest excess risk, especially in women [female SIR 114.7 (95% CI 66.8, 183.6); male SIR 17.5 (95% CI 8.72, 31.2)]. The next two most common cancers were non-Hodgkin's lymphoma and skin cancer [SIR 20.3 (95% CI 13.6, 29.1) and 24.7 (95% CI 15.3-37.8), respectively]. Future studies are needed to identify the risk factors and assess the need for systematic screening among PTMs with excess risk in KTRs.

Pre-Transplant Hyperparathyroidism and Graft or Patient Outcomes After Kidney Transplantation

The impact of pre-transplant parathyroid hormone (PTH) levels on early or long-term kidney function after kidney transplantation is subject of debate. We assessed whether severe hyperparathyroidism is associated with delayed graft function (DGF), death-censored graft failure (DCGF), or all-cause mortality. In this single-center cohort study, we studied the relationship between PTH and other parameters related to bone and mineral metabolism, including serum alkaline phosphatase (ALP) at time of transplantation with the subsequent risk of DGF, DCGF and all-cause mortality using multivariable logistic and Cox regression analyses. In 1,576 kidney transplant recipients (51.6 ± 14.0 years, 57.3% male), severe hyperparathyroidism characterized by pre-transplant PTH ≥771 pg/mL (>9 times the upper limit) was present in 121 patients. During 5.2 [0.2-30.0] years follow-up, 278 (15.7%) patients developed DGF, 150 (9.9%) DCGF and 432 (28.6%) died. A higher pre-transplant PTH was not associated with DGF (HR 1.06 [0.90-1.25]), DCGF (HR 0.98 [0.87-1.13]), or all-cause mortality (HR 1.02 [0.93-1.11]). Results were consistent in sensitivity analyses. The same applied to other parameters related to bone and mineral metabolism, including ALP. Severe pre-transplant hyperparathyroidism was not associated with an increased risk of DGF, DCGF or all-cause mortality, not supporting the need of correction before kidney transplantation to improve graft or patient survival.