Patient and graft survival in older kidney transplant recipients: does age matter?

An increasing gap between supply and demand of donor kidneys for transplantation exists. There is concern regarding the allocation of scarce organs to elderly patients, because the benefit obtained by the transplant may be less in elderly compared with younger recipients. It was the objective of this study to determine differences in patient and organ survival between organ recipients >65 yr and 50 to 64 yr of age at transplantation. A retrospective cohort of 627 patients >50 yr who received a kidney transplant between 1993 and 2000 was assembled. Detailed information on patient demographics, comorbidities, and immunological and donor characteristics was ascertained before transplantation. Five-year patient and graft survival were evaluated by Kaplan-Meier survival curves and multivariate Cox proportional-hazard models. Five-year patient mortality was similar between patients aged >65 and 60 to 64 at transplantation (relative risk [RR] = 1.07; 95% confidence interval [CI], 0.66 to 1.74). Patients aged 50 to 59 yr showed a clear trend toward lower 5-yr mortality (RR = 0.66; 95% CI, 0.43 to 1.03). Compared with patients >65 yr, 5-yr graft loss was not different in patients aged 60 to 64 (RR = 1.28; 95% CI, 0.82 to 2.02) or those aged 50 to 59 yr at transplantation (RR = 1.02; 95% CI, 0.68 to 1.53). After thorough control for confounding, 5-yr graft survival was not materially different by age group. Discrimination against older candidates for kidney transplantation on age-related grounds alone is not warranted.     

Modified ELISPOT technique — Highly significant inverse correlation of post-Tx donor-reactive IFNγ-producing cell frequencies with 6 and 12 months graft function in kidney transplant recipients

BackgroundUpcoming trials for immunosuppression minimization and tolerance induction require the development of reliable in vitro assays for monitoring cellular alloimmunity in transplant patients. The IFN-γ ELISPOT assay represents a promising tool for monitoring alloreactive memory/effector T cells. As T lymphopenia is a common finding during the early post-transplant (post-Tx) period, the IFN-γ ELISPOT technique was here modified by using ELISPOT responder cells with enhanced percentage and standardized number of 200,000 T cells per well.MethodsPeripheral blood mononuclear cells (PBMNC) of kidney transplant recipients were depleted of CD14+ and CD15+ cells to increase the percentage of T cells from average 47.8% to 71.5% before transplantation (pre-Tx) and from 39.7% to 74.9% post-Tx. The assay was tested in a population of 23 de novo renal transplant patients for clinical relevance. Before and at 2–3 times during the first 6 months post-Tx, IFN-γ-producing donor-reactive as well as recall antigen-reactive cell frequencies (Candida, tuberculin, tetanus) were determined and correlated with outcome.ResultsPre-Tx donor-reactive ELISPOT frequencies were enhanced in patients with acute rejection compared to non-rejectors. Moreover, mean post-Tx donor-reactive ELISPOT frequencies showed a highly significant inverse correlation with renal function at 6 and 12 months. In contrast, recall antigen-reactive ELISPOT frequencies did not correlate with outcome.ConclusionOur results suggest that the modified donor-reactive ELISPOT approach might provide a useful surrogate marker for renal transplant outcome with possible utility especially in T-lymphopenic patients.     

The association of living donor source with patient and graft survival among kidney transplant recipients in the ERA-EDTA Registry – a retrospective study

In this study we aimed to compare patient and graft survival of kidney transplant recipients who received a kidney from a living-related donor (LRD) or living-unrelated donor (LUD). Adult patients in the ERA-EDTA Registry who received their first kidney transplant in 1998–2017 were included. Ten-year patient and graft survival were compared between LRD and LUD transplants using Cox regression analysis. In total, 14 370 patients received a kidney from a living donor. Of those, 9212 (64.1%) grafts were from a LRD, 5063 (35.2%) from a LUD and for 95 (0.7%), the donor type was unknown. Unadjusted five-year risks of death and graft failure (including death as event) were lower for LRD transplants than for LUD grafts: 4.2% (95% confidence interval [CI]: 3.7–4.6) and 10.8% (95% CI: 10.1–11.5) versus 6.5% (95% CI: 5.7–7.4) and 12.2% (95% CI: 11.2–13.3), respectively. However, after adjusting for potential confounders, associations disappeared with hazard ratios of 0.99 (95% CI: 0.87–1.13) for patient survival and 1.03 (95% CI: 0.94–1.14) for graft survival. Unadjusted risk of death-censored graft failure was similar, but after adjustment, it was higher for LUD transplants (1.19; 95% CI: 1.04–1.35). In conclusion, patient and graft survival of LRD and LUD kidney transplant recipients was similar, whereas death-censored graft failure was higher in LUD. These findings confirm the importance of both living kidney donor types.     

Long-term follow-up of ACE-inhibitor versus β-blocker treatment and their effects on blood pressure and kidney function in renal transplant recipients

Hypertension and nephrotoxicity are frequent complications of cyclosporine-induced immunosuppression in renal transplant recipients. Long-term antihypertensive treatment is obligatory for hypertensive transplant patients, to protect allograft function. The use of angiotensin-converting enzyme (ACE) inhibitors in the anti-hypertensive treatment of renal transplant recipients who receive immunosuppression with cyclosporine has long been discussed controversially. The aim of this prospective study, with a duration of 2 years and a follow-up of another 3 years, was to estimate the long-term antihypertensive potential of quinapril compared with that of the beta-blocker atenolol and to compare their effects on renal allograft function and proteinuria in 96 hypertensive renal transplant recipients who received cyclosporine A as immunosuppressive therapy. Patients were randomly assigned to receive either quinapril (group Q) or atenolol (group A) as anti-hypertensive treatment. Forty patients of each group completed the 5-year observation period according to protocol. Intention-to-treat and according-to-protocol analyses were performed. With the patients starting at similar baseline blood pressure values, both agents, atenolol and quinapril, decreased systolic and diastolic blood pressure (SBP, DBP) as well as middle arterial pressure (MAP) and pulse pressure (PP) to a similar extent (Delta SBP: group Q: -8+/-3 vs group A mmHg: -5+/-3; Delta DBP: -5+/-2 vs -4+/-2 mmHg; Delta MAP: -6+/-2 vs -5+/-2 mmHg; Delta PP: -2+/-2 vs -1+/-3 mmHg; mean +/- SEM). Neither serum creatinine levels nor Cockcroft-Gault clearance had changed significantly in either group after the 5-year period (Delta creatinine: 0.1+/-0.1 vs 0.2+/-0.2 mg/dl; Delta Cockcroft-Gault clearance: 3.9+/-4.6 vs 2.8+/-4.3 ml/min; mean +/- SEM). Urinary protein excretion remained stable among the quinapril-treated patients, whereas a significant increase was observed in the atenolol group during the 5-year study period (group Q: from 0.52+/-0.08 to 0.54+/-0.14 g/24 h; group A: from 0.34+/-0.03 to 0.72+/-0.13 g/24 h, P<0.02; mean +/- SEM). Albuminuria increased comparably in both groups, while the excretion of alpha-microglobuline increased slightly in the atenolol group, but decreased slightly in the quinapril group. The difference between the groups failed to be statistically significant (ANOVA, P<0.056). In conclusion, quinapril and atenolol may be considered suitable and safe substances in the long-term treatment of hypertensive renal transplant recipients, since both agents prove to be effective in anti-hypertensive treatment, and keep allograft function stable over a period of 5 years.     

Immunosuppression in kidney transplant recipients with COVID-19 infection – where do we stand and where are we heading?

The appropriate immunosuppressive regimen in kidney transplant recipients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2/COVID-19) infection remains unclear. The impact of direct virus injury complicated by dysregulated hyperimmune response with overwhelming release of various cytokines in COVID-19 infected subjects contributes to the complexity of management. The largest concern of the practicing clinicians at current time is how to tailor maintenance immune-modulating therapy during active viral infection and the efficacy of the soon-to-be upcoming immunization for COVID-19. This targeted review aims to cover most of the current evidence on the effect of key maintenance immunosuppressive agents in COVID-19 infection and proposes a line of management to specific scenarios on this very rapidly evolving subject.     

Molecular-level HLA mismatch is associated with rejection and worsened graft survival in heart transplant recipients – a retrospective study

The aim was to evaluate the association of molecular-level human leukocyte antigen (HLA) mismatching with post-transplant graft survival, rejection, and cardiac allograft vasculopathy (CAV). We retrospectively analyzed all primary cardiac transplant recipients between 01/1984-06/2016. 1167 patients fulfilled inclusion criteria and had HLA typing information available. In 312 donor-recipient pairs, typing at serological split antigen level was available. We used the Epitope MisMatch Algorithm to calculate the number of amino acid differences in antibody-verified HLA eplets (amino acid mismatch load (AAMM)) between donor and recipient. Patients with a higher HLA-DR AAMM load had inferior 1-year graft survival (hazard ratio [HR], 1.14; 95% confidence interval [CI], 1.01–1.28). The HLA-AB AAMM load showed no impact on graft survival. In the subgroup with available split-level information, we observed an inferior graft survival for a higher HLA-DR AAMM load 3 months after transplantation (HR, 1.22; 95% CI, 1.04–1.44) and a higher risk for rejection for an increasing HLA-AB (HR, 1.70; 95% CI, 1.29–2.24) and HLA-DR (HR, 1.32; 95% CI, 1.09–1.61) AAMM load. No impact on the development of CAV was found. Molecular-level HLA mismatch analysis could serve as a tool for risk stratification after heart transplantation and might take us one step further into precision medicine.     

Symptomatic atherosclerotic vascular disease and graft survival in primary kidney transplant recipients – Observational analysis of the united network of organ sharing database

ObjectivesThe aim of this study was to investigate whether symptomatic atherosclerotic vascular disease (SAVD) was associated with graft survival in primary kidney transplant recipients.Summary background dataRecipient atherosclerotic vascular disease is associated with increased mortality rates amongst renal transplant patients. However, its relationship with graft survival has not been well studied.MethodsThis retrospective observational analysis was performed using data for adult kidney transplant recipients between 11/09/2000 and 28/02/2020 extracted from the UNOS national organ transplantation database. Patients were divided into two groups based on recipient history of symptomatic atherosclerotic disease (angina or peripheral vascular disease). Risk-adjusted outcomes were assessed by multivariate Cox regression analysis adjusting for both donor and recipient characteristics.Results11,771 adult kidney transplant recipients from the UNOS database were eligible for analysis (1543 had a history of SAVD, 10,228 did not have a history of SAVD). After adjusting for confounders, positive SAVD status was associated with an adverse effect on graft survival at both 1 year (HR 1.35, p < 0.001) and 10 years (HR 1.15, p < 0.001).ConclusionsSAVD should be considered an independent risk factor for poor prognosis in patients undergoing kidney transplant.     

Delivery in female kidney transplant recipients with hepatitis C virus infection: is it safe for mother and newborn?

The aim of this report is to evaluate whether pregnancy is a risk factor for poor outcome of infection with hepatitis C virus or for allograft deterioration among kidney transplant recipients. The first case was in a 41-year-old pregnant kidney transplant recipient with hypercreatinemia and a history of toxic hepatitis. The second case was treated with interferon before transplant. Tacrolimus-based immunosuppressive regimens were used during the pregnancies. Hypertension complicated both pregnancies, and the pregnancies ended with cesarean delivery at preterm and term with healthy but low-weight newborns. The first patient became positive for hepatitis C virus RNA after pregnancy without a flare in transaminase level. Antibodies to hepatitis C virus were negative in the newborns. In conclusion, pregnancy should be promoted for kidney recipients infected with hepatitis C virus who have stable graft and liver function.     

Can daclizumab reduce acute rejection and improve long‐term renal function in tacrolimus‐based primary renal transplant recipients?

SUMMARY: Aims: To evaluate the efficacy and safety of a tacrolimus‐based immunosuppressive regimen with and without induction therapy using daclizumab in first cadaveric renal transplant recipients. Methods: Since January 2001, we studied the effect of daclizumab in a non‐randomized and prospective study of 36 sequential first cadaveric renal transplant recipients. They were compared with a historical control group of 21 sequential first cadaveric renal transplant recipients without induction therapy. All patients received tacrolimus, azathioprine and corticosteroids as concomitant immunosuppressive therapy. Daclizumab was given at 1 mg/kg infusion 2 h before transplantation and then every 14 days for four more doses. Outcomes measured included incidence of acute rejection, patient survival, graft survival, annualized change in creatinine clearance (CrCl), cardiovascular risk profile, infection and malignancy. Results: Fewer biopsy proven acute rejections were observed in the induction treatment group: 11.1% (4/36) versus 19% (4/21) but the rejection free survival was similar (P = 0.37). The patient survival and graft survival were comparable. The renal function was similar in both groups. There were also no significant difference in infection, malignancy and cardiovascular risk profile in both groups. Conclusion: Adding daclizumab to a tacrolimus‐based therapy is safe but cannot further improve clinical efficacy.     

Longitudinal assessment of the CXCL10 blood and urine concentration in kidney transplant recipients with BK polyomavirus replication—a retrospective study

In kidney transplant recipients (KTRs), BK polyomavirus (BKPyV) replication may progress to polyomavirus-associated nephropathy (PVAN). In this retrospective study, we assessed the chemokine CXCL10 in urine and blood samples consecutively acquired from 85 KTRs who displayed different stages of BKPyV replication and eventually developed PVAN. In parallel to progression toward PVAN, CXCL10 gradually increased in blood and urine, from baseline (prior to virus replication) to BKPyV DNAuria (median increase in blood: 42.15 pg/ml, P = 0.0156), from mere DNAuria to low- and high-level BKPyV DNAemia (median increase: 52.60 and 87.26 pg/ml, P = 0.0010 and P = 0.0002, respectively) and peaked with histologically confirmed PVAN (median increase: 145.00 pg/ml, P < 0.0001). CXCL10 blood and urine levels significantly differed among KTRs with respect to simultaneous presence of human cytomegalovirus (P < 0.001) as well as in relation to the clinical severity of respective BKPyV DNAemia episodes (P = 0.0195). CXCL-10 concentrations were particularly lower in KTRs in whom BKPyV DNAemia remained without clinical evidence for PVAN, as compared to individuals who displayed high decoy cell levels, decreased renal function and/or biopsy-proven PVAN (median blood concentration: 266.97 vs. 426.42 pg/ml, P = 0.0282). In conclusion, in KTRs CXCL10 rises in parallel to BKPyV replication and correlates with the gradual development of PVAN.     

Association of graft survival with tacrolimus exposure and late intra-patient tacrolimus variability in pediatric and young adult renal transplant recipients—an international CTS registry analysis

Adolescent and young adult age is a high-risk window with an alarmingly increased likelihood of premature kidney graft loss due to immunological rejection. Using the large database of the Collaborative Transplant Study, we analyzed whether a more intense and less variable exposure to tacrolimus could counteract this young age-related enhanced immunoreactivity. Kidney graft recipients aged 12–23 years (n = 964) with a 1-year tacrolimus trough level between 4.0 and 10.9 ng/ml had a 5-year graft survival rate of 85.1%, significantly better than the poor 66.1% rate in patients with a trough level below 4.0 ng/ml who showed a 2.38-fold increased risk of graft loss in the multivariable analysis (P < 0.001). This association was not apparent in young children aged 0–11 years (n = 455) and less pronounced in adults aged 24–34 years (n = 1466). However, an intra-patient variability of tacrolimus (IPV) trough level ≥1.5 at post-transplant years 1 and 2 was associated with an increased graft loss risk in both 12- to 23-year-old and 0- to 11-year-old recipients (P < 0.001 and P = 0.045). Patients with high IPV made up as many as 30% of kidney graft recipients, indicating that a more intense and less variable exposure to tacrolimus could improve graft survival strongly in this high-risk group.     

Reduced CD4+ CD25++ CD45RA− Foxp3hi activated regulatory T cells and its association with acute rejection in patients with kidney transplantation

BackgroundIt was found that regulatory T cells (Tregs) importantly affect the maintenance of the kidney graft. However, Tregs are a heterogeneous population with less to more suppressive activity. The aim of this study was to determine the effects of different subsets of Tregs, as well as their ratio to effector T cells (Teff), on kidney transplantation outcomes.MethodsA total of 58 participants were enrolled in this study and divided into four groups: (i) first kidney transplant recipients (stable 1); (ii) second kidney transplant recipients (stable 2); (iii) transplant recipients with acute rejection (AR); and (iv) healthy control subjects. By using flow cytometer, the frequencies of CD4⁺ CD25⁺⁺ CD45RA⁻ Foxp3^hi activated Tregs (aTregs), CD4⁺ CD25⁺ CD45RA⁺ Foxp3^lo resting Tregs (rTregs), CD4⁺ CD25⁺ CD45RA⁻ Foxp3^lo non-suppressive T cells, CD4⁺ CD25⁺ Foxp3⁻ cells Teff, and total Tregs were analyzed in all subjects.ResultsThe frequency of aTregs (as well as the ratio of aTregs/Tregs) was significantly lower in the AR patients than the other three groups. In contrast to AR patients, stables 1 and 2 had a higher aTreg/Treg ratio than those in the control group. Although patients with AR had a significantly lower total Tregs than the other three groups, the balance of total Tregs and Teff was similar between patients with and without AR.ConclusionPatients with AR had poorer immunoregulatory properties than those with normal graft functioning, as well as those in the control group. These reduced immunoregulatory properties in patients with AR could lead to graft rejection.     

Cystectomy and orthotopic ileal neobladder in a male patient 12 years after kidney transplantation; good preservation of the renal function

In case of cystectomy, some forms of urinary diversion can impair the graft function of renal transplant patients. Here we present the case of a 70-year-old male with carcinoma of the bladder 12 years after renal transplantation. Immunosuppression was achieved with Cyclosporin A (200 mg/day) and Prednisone (5 mg/day). The patients serum creatinine level was 1.4 mg/dl. Following cystectomy, an orthotopic ileal neobladder was constructed by means of Studer technique, and the afferent ileal loop was anastomosed to the graft ureter. Pathology revealed pT1 G3 N+ transitional cell carcinoma. Ten months later, periaortic nodal recurrences necessitated four cycles of chemotherapy with Epidoxorubicyn and Gemcytabine. To date, 20 months after cystectomy, the patient is stable, with day and night-time urinary continence. His serum creatinine level is 1.3 mg/dl, and there is no evidence of hydronephrosis or acidosis. We conclude that the orthotopic ileal neobladder is an effective form of urinary diversion in renal transplant patients requiring cystectomy, allowing good preservation of the renal function.Abbreviations BCG Bacillus Calmette Guèrin     

Analysis of profibrogenic microRNAs (miRNAs) expression in urine and serum of chronic kidney disease (CKD) stage 1–4 patients and their relationship with proteinuria and kidney function

International Urology and Nephrology - Besides conventional kidney diseases diagnostics, micro RNAs (miRNAs) assessment in urine and serum is considered to be a promising non-invasive method of...     

Can the Toll-like receptors 4 expression in peripheral blood mononuclear cells help assess the effectiveness of immunosuppression and the chance of a future good renal transplant function?

BackgroundA small percentage of peripheral blood mononuclear cells (PBMCs) circulating during the kidney transplantation (KT) period remain in the blood long after transplantation. A part of the PBMCs penetrates the graft.AimTo examine if the choice of immunosuppression may change TLR4ex and how TLR4ex affects the transplant function in the future.MaterialThe study population-143 transplanted patients (pts) (55 females, 88 males), mean age on recruitment day 50.33 ± 12.8 years old, mean BMI 25.04 ± 4.18. 41 pts. experienced delayed graft function (DGF+). 55 pts. were treated with cyclosporine A (CsA) and 88 with tacrolimus (Tac). All were treated with mofetil mycophenolate (MMF). The PBMCs acquisition and starting point of the follow-up (TLR-day) was at least one month after KT.MethodWe investigated averaged mRNA expression of Toll-like receptors 4 (TLR4ex) in non-stimulated peripheral blood mononuclear cells with the use of real-time polymerase chain reaction. The KT pts. (All, Tac, CsA, DGF+) were divided by the respective median of their TLR4ex (lower: L-TLR4ex, higher: H-TLR4ex). Main clinical parameters and transplant biopsy files (if available) were assessed on TLR-day and post follow-up.ResultsWe found that TLR4ex was reduced for a long time in patients who experienced delayed graft function. L-TLR4ex had a higher proportion of DGF+ patients, and patients treated with CsA but lower of those treated with Tac than in H-TLR4ex. The amplitude of changes in renal function parameters (ΔEGFR%/ΔsCr/ΔsCr%) was clearly less favorable for L-TLR4ex. Tacrolimus expressed a stabilizing effect. Both the positive vasculitis score and chronic graft nephropathy were more frequent in the L-TLR4ex group. On TLR-day an association of renal function and Tac concentration with TLR4ex was clear only in the tacrolimus population. The TLR4ex was lower in patients with a future deterioration of the graft function.ConclusionIn kidney transplant recipients the occurrence of DGF results in a long-term reduction of the averaged TLR4ex in PBMC. Tacrolimus exerts a clear, stabilizing, positive and dose-dependent effect on TLR4ex. An improvement in renal transplant function may be expected in KT patients with high TLR4ex. Evaluation of the averaged TLR4ex can be used to assess the efficacy of immunosuppression in the treatment with tacrolimus and to estimate the likelihood of deterioration in renal function.