Project description:Rationale & objectiveDonor acute kidney injury (AKI) activates innate immunity, enhances HLA expression in the kidney allograft, and provokes recipient alloimmune responses. We hypothesized that injury and inflammation that manifested in deceased-donor urine biomarkers would be associated with higher rates of biopsy-proven acute rejection (BPAR) and allograft failure after transplantation.Study designProspective cohort.Setting & participants862 deceased donors for 1,137 kidney recipients at 13 centers.ExposuresWe measured concentrations of interleukin 18 (IL-18), kidney injury molecule 1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) in deceased donor urine. We also used the Acute Kidney Injury Network (AKIN) criteria to assess donor clinical AKI.OutcomesThe primary outcome was a composite of BPAR and graft failure (not from death). A secondary outcome was the composite of BPAR, graft failure, and/or de novo donor-specific antibody (DSA). Outcomes were ascertained in the first posttransplant year.Analytical approachMultivariable Fine-Gray models with death as a competing risk.ResultsMean recipient age was 54 ± 13 (SD) years, and 82% received antithymocyte globulin. We found no significant associations between donor urinary IL-18, KIM-1, and NGAL and the primary outcome (subdistribution hazard ratio [HR] for highest vs lowest tertile of 0.76 [95% CI, 0.45-1.28], 1.20 [95% CI, 0.69-2.07], and 1.14 [95% CI, 0.71-1.84], respectively). In secondary analyses, we detected no significant associations between clinically defined AKI and the primary outcome or between donor biomarkers and the composite outcome of BPAR, graft failure, and/or de novo DSA.LimitationsBPAR was ascertained through for-cause biopsies, not surveillance biopsies.ConclusionsIn a large cohort of kidney recipients who almost all received induction with thymoglobulin, donor injury biomarkers were associated with neither graft failure and rejection nor a secondary outcome that included de novo DSA. These findings provide some reassurance that centers can successfully manage immunological complications using deceased-donor kidneys with AKI.
Project description:By 21 March 2020 infections related to the novel coronavirus SARS-CoV-2 had affected people from 177 countries and caused 11,252 reported deaths worldwide. Little is known about risk, presentation and outcomes of SARS-CoV-2 (COVID-19) infection in kidney transplantation recipients, who may be at high-risk due to long-term immunosuppression, comorbidity and residual chronic kidney disease. Whilst COVID-19 is predominantly a respiratory disease, in severe cases it can cause kidney and multi-organ failure. It is unknown if immunocompromised hosts are at higher risk of more severe systemic disease. Therefore, we report on seven cases of COVID-19 in kidney transplant recipients (median age 54 (range 45-69), three females, from a cohort of 2082 managed transplant follow-up patients) over a six-week period in three south London hospitals. Two of seven patients presented within three months of transplantation. Overall, two were managed on an out-patient basis, but the remaining five required hospital admission, four in intensive care units. All patients displayed respiratory symptoms and fever. Other common clinical features included hypoxia, chest crepitation, lymphopenia and high C-reactive protein. Very high D dimer, ferritin and troponin levels occurred in severe cases and likely prognostic. Immunosuppression was modified in six of seven patients. Three patients with severe disease were diabetic. During a three week follow up one patient recovered, and one patient died. Thus, our findings suggest COVID-19 infection in kidney transplant patients may be severe, requiring intensive care admission. The symptoms are predominantly respiratory and associated with fever. Most patients had their immunosuppression reduced and were treated with supportive therapy.
Project description:BackgroundDeclining rates of acute rejection (AR) and the high rate of 1-year graft survival among patients with AR have prompted re-examination of AR as an outcome in the clinic and in trials. Yet AR and its treatment may directly or indirectly affect longer-term outcomes for kidney transplant recipients.MethodsTo understand the long-term effect of AR on outcomes, we analyzed data from the Australia and New Zealand Dialysis and Transplant Registry, including 13,614 recipients of a primary kidney-only transplant between 1997 and 2017 with at least 6 months of graft function. The associations between AR within 6 months post-transplant and subsequent cause-specific graft loss and death were determined using Cox models adjusted for baseline donor, recipient, and transplant characteristics.ResultsAR occurred in 2906 recipients (21.4%) and was associated with graft loss attributed to chronic allograft nephropathy (hazard ratio [HR], 1.39; 95% confidence interval [95% CI], 1.23 to 1.56) and recurrent AR beyond month 6 (HR, 1.85; 95% CI, 1.39 to 2.46). Early AR was also associated with death with a functioning graft (HR, 1.22; 95% CI, 1.08 to 1.36), and with death due to cardiovascular disease (HR, 1.30; 95% CI, 1.11 to 1.53) and cancer (HR, 1.35; 95% CI, 1.12 to 1.64). Sensitivity analyses restricted to subgroups with either biopsy-proven, antibody-mediated, or vascular rejection, or stratified by treatment response produced similar results.ConclusionsAR is associated with increased risks of longer-term graft failure and death, particularly death from cardiovascular disease and cancer. The results suggest AR remains an important short-term outcome to monitor in kidney transplantation and clinical trials.
Project description:BackgroundThe optimal immunosuppressive regimen in simultaneous pancreas-kidney transplant (SPKT) recipients that prevents acute rejection episodes (AREs) and allows optimal outcome remains elusive.MethodsThis cohort study assessed incidence and time to AREs in 73 consecutive SPKT recipients receiving alemtuzumab induction and steroid-free maintenance with tacrolimus and mycophenolate mofetil. A cohort with single high-dose antithymocyte globulin (ATG; n = 85) and triple therapy served as controls. In addition, we provided mechanistic insights in AREs after alemtuzumab depletion, including composition and alloreactivity of lymphocytes (flow cytometry and mixed lymphocyte reaction) plasma alemtuzumab levels (enzyme-linked immunosorbent assay), and maintenance drug exposure.ResultsOverall number of AREs at 3 years was significantly lower with alemtuzumab versus ATG induction (26.0% vs 43.5%; adjusted hazard ratio, 0.38; P = 0.029). Most AREs (94.6%) with ATG occurred within the first month, whereas 84.2% of AREs with alemtuzumab occurred beyond 3 months. Patients with and without an ARE in the steroid-free alemtuzumab group showed no differences in composition of lymphocytes, or in alemtuzumab levels. Of note, more than two thirds of these AREs were preceded by empiric tacrolimus and/or mycophenolate mofetil dose adjustments due to viral infections, leukopenia, or gastrointestinal symptoms.ConclusionsAlemtuzumab induction resulted in a significant lower incidence of AREs. Empiric dose adjustments beyond 3 months in the absence of steroids carry a significant risk for subsequent rejection in SPKT recipients.
Project description:Background and objectivesThe current allocation algorithm for deceased donor kidney transplantation takes into consideration HLA mismatches at the ABDR loci but not HLA mismatches at other loci, including HLA-DQ. However, the independent effects of incompatibilities for the closely linked HLA-DQ antigens in the context of HLA-DR antigen matched and mismatched allografts are uncertain. We aimed to determine the effect of HLA-DQ mismatches on renal allograft outcomes.Design, setting, participants, & measurementsUsing data from the Australia and New Zealand Dialysis and Transplant Registry, we examined the association between HLA-DQ mismatches and acute rejections in primary live and deceased donor kidney transplant recipients between 2004 and 2012 using adjusted Cox regression models.ResultsOf the 788 recipients followed for a median of 2.8 years (resulting in 2891 person-years), 321 (40.7%) and 467 (59.3%) received zero and one or two HLA-DQ mismatched kidneys, respectively. Compared with recipients who have received zero HLA-DQ mismatched kidneys, those who have received one or two HLA-DQ mismatched kidneys experienced greater numbers of any rejection (50 of 321 versus 117 of 467; P<0.01), late rejections (occurring >6 months post-transplant; 8 of 321 versus 27 of 467; P=0.03), and antibody-mediated rejections (AMRs; 12 of 321 versus 38 of 467; P=0.01). Compared with recipients of zero HLA-DQ mismatched kidneys, the adjusted hazard ratios for any and late rejections in recipients who had received one or two HLA-DQ mismatched kidneys were 1.54 (95% confidence interval [95% CI], 1.08 to 2.19) and 2.85 (95% CI, 1.05 to 7.75), respectively. HLA-DR was an effect modifier between HLA-DQ mismatches and AMR (P value for interaction =0.02), such that the association between HLA-DQ mismatches and AMR was statistically significant in those who have received one or two HLA-DR mismatched kidneys, with adjusted hazard ratio of 2.50 (95% CI, 1.05 to 5.94).ConclusionsHLA-DQ mismatches are associated with acute rejection, independent of HLA-ABDR mismatches and initial immunosuppression. Clinicians should be aware of the potential importance of HLA-DQ matching in the assessment of immunologic risk in kidney transplant recipients.
Project description:Coronavirus disease 2019 (COVID-19) is associated with increased morbidity and mortality among kidney transplant recipients (KTRs). The administration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is the only reliable strategy to prevent COVID-19 and alleviate the severity of COVID-19 in this particular population. The aim of this article was to evaluate the clinical protection by vaccines (breakthrough infections, deaths, and hospitalizations) in KTRs. There were 135 KTRs with COVID-19 breakthrough infections for whom patient-level data were available in PubMed and Web of Science. There was a male predominance (61.4%), 97 were given the standard vaccination regimen, and 38 received three or four doses of the vaccine. The median age was 59.0 (IQR: 49.0-69.0) years. A total of 67 patients were hospitalized, and 10 patients died. In 72.6% of cases, triple-maintenance immunosuppression was employed. The deceased patients were older than the survivors (p < 0.05); an age over 60 years was a risk factor for death (p < 0.05). The KTRs with booster vaccines had a longer time interval from the last vaccine to COVID-19 infection and lower hospitalization rates than the individuals who received the standard vaccination regimen (33.3% vs. 54.8%, p < 0.05). The hospitalized patients were older than the outpatients (p < 0.05). Among 16,820 fully vaccinated or boosted KTRs from 14 centers, there were 633 breakthrough infections (3.58%) and 73 associated deaths (0.41%). The center-level breakthrough infection rates varied from 0.21% to 9.29%. These findings highlight the need for booster doses for KTRs. However, more research is needed to define the long-term effectiveness and immunogenicity of booster doses and to identify methods to boost the protective response to vaccination in these immunocompromised patients.
Project description:Background:Despite being the leading cause of graft failure, there is a lack of published data about the rates of rejection in kidney transplant patients with glomerulonephritis as the cause of end-stage renal disease. Methods:We examined all consecutive adult (>18 years) renal transplant recipients with biopsy-proven native renal glomerular disease who underwent kidney transplant between 1994 and 2013. Glomerulonephritis groups included were IgA nephropathy (IgAN) (N = 306), focal segmental glomerulosclerosis (FSGS) (N = 298), membranous nephropathy (MN) (N = 81), and lupus nephritis (LN) (N = 177). Results:In the total cohort of 862 patients, 363 patients had an episode of acute rejection during the follow-up period of 19 years (incidence rate of 7.2% per year). Forty-five of 81 patients with MN had an episode of acute rejection during the follow-up period. Patients with MN had significantly higher incidence of acute rejection (12.1 per 100 person years, P < 0.05) in comparison to IgAN (7.2 per 100 person years), FSGS (7.4 per 100 person years), and LN (7.9 per 100 person years). Patients with MN had 1.9 times higher risk of developing acute rejection after transplant in comparison to IgAN (P < 0.005). In patients with MN, 33 of 45 (73.3%) rejection events were acute cellular rejection, 8 (17.8%) of 45 were acute antibody-mediated rejection and 6 of 45 (13.3%) were combined cellular and antibody-mediated acute rejection. Despite higher rates of acute rejection, 10-year allograft survival was similar in all subgroups. Conclusions:Patients with MN have higher incidence of acute rejection after kidney transplant but have similar 10-year allograft survival in comparison to the other glomerular diseases like IgAN, FSGS, and LN.
Project description:BackgroundThe diagnosis of borderline rejection (BLR) ranges from mild inflammation to clinically significant TCMR and is associated with an increased risk of allograft dysfunction. Currently, there is no consensus regarding its treatment due in part to a lack of biomarkers to identify cases with increased risk for immune-mediated injury.MethodsWe identified 60 of 924 kidney transplant recipients (KTRs) with isolated and untreated BLR. We analyzed the impact of predicted indirectly recognizable HLA epitopes (PIRCHE) score on future rejection, de novo DSA development, and recovery to baseline allograft function. Additionally, we compared the outcomes of different Banff rejection phenotypes.ResultsTotal PIRCHE scores were significantly higher in KTRs with BLR compared to the entire study population (p=0.016). Among KTRs with BLR total PIRCHE scores were significantly higher in KTRs who developed TCMR/ABMR in follow-up biopsies (p=0.029). Notably, the most significant difference was found in PIRCHE scores for the HLA-A locus (p=0.010). PIRCHE scores were not associated with the development of de novo DSA or recovery to baseline allograft function among KTRs with BLR (p>0.05). However, KTRs under cyclosporine-based immunosuppression were more likely to develop de novo DSA (p=0.033) than those with tacrolimus, whereas KTRs undergoing retransplantation were less likely to recover to baseline allograft function (p=0.003).ConclusionsHigh PIRCHE scores put KTRs with BLR at an increased risk for future TCMR/ABMR and contribute to improved immunological risk stratification. The benefit of anti-rejection treatment, however, needs to be evaluated in future studies.