Comparing the prognostic performance of iBOX and biopsy-proven acute rejection for long-term kidney graft survival

Biopsy-proven acute rejection (BPAR) occurs in approximately 10% of kidney transplant recipients in the first year, making superiority trials unfeasible. iBOX, a quantitative composite of estimated glomerular filtration rate, proteinuria, antihuman leukocyte antigen donor-specific antibody, and + full/- abbreviated kidney histopathology, is a new proposed surrogate endpoint. BPAR's prognostic ability was compared with iBOX in a pooled cohort of 1534 kidney transplant recipients from 4 data sets, including 2 prospective randomized controlled trials. Discrimination analyses showed mean c-statistic differences between both iBOX compared with BPAR of 0.25 (95% confidence interval: 0.17-0.32) for full iBOX and 0.24 (95% confidence interval: 0.16-0.32) for abbreviated iBOX, indicating statistically significantly higher c-statistic values for the iBOX prognosis of death-censored graft survival. Mean (± standard error) c-statistics were 0.81 ± 0.03 for full iBOX, 0.80 ± 0.03 for abbreviated iBOX, and 0.57 ± 0.03 for BPAR. In calibration analyses, predicted graft loss events from both iBOX models were not significantly different from those observed. However, for BPAR, the predicted events were significantly (P < .01) different (observed: 64; predicted: 70; full iBOX: 76; abbreviated iBOX: 173 BPAR). IBOX at 1-year posttransplant is superior to BPAR in the first year posttransplant in graft loss prognostic performance, providing valuable additional information and facilitating the demonstration of superiority of novel immunosuppressive regimens.

Highly Sensitized Candidates Remain at Risk for Microvascular Inflammation Even When Donor-specific Antibody Is Avoided: A Matched Cohort Study

BACKGROUND

Microvascular inflammation (MVI) is a key feature of antibody-mediated rejection (AMR) among patients with HLA donor-specific antibody (DSA), but MVI at AMR thresholds (Banff glomerulitis [g] + peritubular capillaritis [ptc] score ≥ 2) without DSA has been increasingly recognized. We aimed to determine the incidence of MVI among highly sensitized kidney transplant recipients without DSA.

METHODS

We performed a single-center, retrospective, matched cohort study comparing outcomes of kidney transplant recipients with cPRA ≥90% with preexisting DSA (n = 49), cPRA ≥90% without preexisting DSA (n = 47), and matched controls with cPRA = 0 without preexisting DSA (n = 49). Controls were matched by age, donor type, and transplant date. Indication and surveillance biopsies combined with annual de novo DSA screening were obtained.

RESULTS

Kidney transplant recipients with a cPRA ≥90% and no evidence of preexisting or de novo DSA had a higher incidence of MVI (glomerulitis + peritubular capillaritis ≥ 2) than patients with cPRA = 0 [35% (17/49) versus 12% (6/49), P = 0.0003] over a median (interquartile range) follow-up of 5 (4-6) y posttransplant. Among this cPRA ≥90% group without DSA, MVI persisted in 54% of cases on follow-up biopsy (7/13), and 24% (4/13) of cases developed transplant glomerulopathy (Banff cg score > 0).

CONCLUSIONS

Highly sensitized transplant recipients have a high incidence of persistent and progressive MVI, even without DSA. The mechanisms underlying these histologic features needs to be elucidated, but this information is important to consider when making decisions about transplantation among highly sensitized individuals.

Isatuximab Monotherapy for Desensitization in Highly Sensitized Patients Awaiting Kidney Transplant

SIGNIFICANCE STATEMENT

There is no standardized desensitization regimen for kidney transplant candidates. CD38, expressed by plasma cells, could be targeted for desensitization to deplete plasma cells producing alloantibodies and donor-specific antibodies. Few studies and case reports are available regarding the use of CD38 antibodies for desensitization in patients awaiting kidney transplant. This study shows that isatuximab, a CD38-targeting therapy, was well tolerated in kidney transplant candidates, with a durable decrease in anti-HLA antibodies and partial desensitization activity. The short treatment period and long follow-up of this study allowed for the understanding of the mechanism and timing for any antibody rebound. Isatuximab could be further investigated as an option for adjunct therapy to existing desensitization for patients on the kidney transplant waitlist.

BACKGROUND

Patients with calculated panel reactive antibody (cPRA) ≥80.00%, particularly those with cPRA ≥99.90%, are considered highly sensitized and underserved by the Kidney Allocation System. Desensitization removes circulating reactive antibodies and/or suppresses antibody production to increase the chances of a negative crossmatch. CD38 is expressed highly on plasma cells, thus is a potential target for desensitization.

METHODS

This was an open-label single-arm phase 1/2 study investigating the safety, pharmacokinetics, and preliminary efficacy of isatuximab in patients awaiting kidney transplantation. There were two cohorts, cohorts A and B, which enrolled cPRA ≥99.90% and 80.00% to <99.90%, respectively.

RESULTS

Twenty-three patients (12 cohort A, 11 cohort B) received isatuximab 10 mg/kg weekly for 4 weeks then every 2 weeks for 8 weeks. Isatuximab was well tolerated with pharmacokinetic and pharmacodynamic profiles that indicated similar exposure to multiple myeloma trials. It resulted in decreases in CD38 + plasmablasts, plasma cells, and NK cells and significant reductions in HLA-specific IgG-producing memory B cells. Overall response rate, on the basis of a predefined composite desensitization end point, was 83.3% and 81.8% in cohorts A and B. Most responders had decreases in anti-HLA antibodies that were maintained for 26 weeks after the last dose. Overall, cPRA values were minimally affected, however, with only 9/23 patients (39%) having cPRA decreases to target levels. By study cutoff (median follow-up of 68 weeks), six patients received transplant offers, of which four were accepted.

CONCLUSIONS

In this open-label trial, isatuximab was well tolerated and resulted in a durable decrease in anti-HLA antibodies with partial desensitization activity.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04294459 .

The Banff 2022 Kidney Meeting Work Plan: Data-driven refinement of the Banff Classification for renal allografts

The XVIth Banff Meeting for Allograft Pathology was held in Banff, Alberta, Canada, from September 19 to 23, 2022, as a joint meeting with the Canadian Society of Transplantation. In addition to a key focus on the impact of microvascular inflammation and biopsy-based transcript analysis on the Banff Classification, further sessions were devoted to other aspects of kidney transplant pathology, in particular T cell-mediated rejection, activity and chronicity indices, digital pathology, xenotransplantation, clinical trials, and surrogate endpoints. Although the output of these sessions has not led to any changes in the classification, the key role of Banff Working Groups in phrasing unanswered questions, and coordinating and disseminating results of investigations addressing these unanswered questions was emphasized. This paper summarizes the key Banff Meeting 2022 sessions not covered in the Banff Kidney Meeting 2022 Report paper and also provides an update on other Banff Working Group activities relevant to kidney allografts.

B Cell-mediated Immune Regulation and the Quest for Transplantation Tolerance

Pathophysiologic function of B cells in graft rejection has been well recognized in transplantation. B cells promote alloantigen-specific T-cell response and secrete antibodies that can cause antibody-mediated graft failures and rejections. Therefore, strategies targeting B cells, for example, B-cell depletion, have been used for the prevention of both acute and chronic rejections. Interestingly, however, recent mounting evidence indicates that subsets of B cells yet to be further identified can display potent immune regulatory functions, and they contribute to transplantation tolerance and operational tolerance in both experimental and clinical settings, respectively. In this review, we integrate currently available information on B-cell subsets, including T-cell Ig domain and mucin domain 1-positive transitional and T-cell immunoreceptor with Ig and immunoreceptor tyrosine-based inhibitory motif domain-positive memory B cells, displaying immune regulatory functions, with a focus on transplantation tolerance, by analyzing their mechanisms of action. In addition, we will discuss potential T-cell Ig domain and mucin domain 1-positive and T-cell immunoreceptor with Ig and immunoreceptor tyrosine-based inhibitory motif domain-positive B cell-based strategies for the enhancement of operational tolerance in transplantation patients.

Impact of pancreas transplantation alone on kidney function: A multicenter clinical cohort study

Pancreas transplantation alone (PTA) is a β cell replacement option for selected patients with type 1 diabetes mellitus; concerns have been raised regarding deterioration in kidney function (KF) after PTA. This retrospective multicenter study assessed actual impact of transplantation and immunosuppression on KF in PTA recipients at three Transplant Centers. The primary composite endpoint 10 years after PTA was >50% eGFR decline, eGFR < 30 mL/min/1.73 m2 , and/or receiving a kidney transplant (KT). Overall, 822 PTA recipients met eligibility. Median baseline and 10-year eGFR (mL/min/1.73 m2 ) were 76.3 (58.1-100.8) and 51.3 (35.3-65.9), respectively. Primary composite endpoint occurred in 98 patients (53.5%) with 45 experiencing a >50% decrease in eGFR by 10 years post-transplant, 38 eGFR < 30 mL/min/1.73 m2 and 49 requiring KT. KF declined most significantly within 6 months post-PTA, more often in females and patients with better preserved GFR up to 5 years with 11.6% kidney failure at 10 years. Patient survival and death-censored graft survival were both 68% at 10 years with overall graft thrombosis rate 8%. KF declined initially after PTA but stabilized with further slow progression. In conclusion, prospective intervention studies are needed to test renal sparing interventions while gathering more granular data.

Qualifying a novel clinical trial endpoint (iBOX) predictive of long-term kidney transplant outcomes

New immunosuppressive therapies that improve long-term graft survival are needed in kidney transplant. Critical Path Institute's Transplant Therapeutics Consortium received a qualification opinion for the iBOX Scoring System as a novel secondary efficacy endpoint for kidney transplant clinical trials through European Medicines Agency's qualification of novel methodologies for drug development. This is the first qualified endpoint for any transplant indication and is now available for use in kidney transplant clinical trials. Although the current efficacy failure endpoint has typically shown the noninferiority of therapeutic regimens, the iBOX Scoring System can be used to demonstrate the superiority of a new immunosuppressive therapy compared to the standard of care from 6 months to 24 months posttransplant in pivotal or exploratory drug therapeutic studies.

Qualifying a Novel Clinical Trial Endpoint (iBOX) Predictive of Long-Term Kidney Transplant Outcomes

New immunosuppressive therapies that improve long-term graft survival are needed in kidney transplant. Critical Path Institute's Transplant Therapeutics Consortium received a qualification opinion for the iBOX Scoring System as a novel secondary efficacy endpoint for kidney transplant clinical trials through European Medicines Agency's qualification of novel methodologies for drug development. This is the first qualified endpoint for any transplant indication and is now available for use in kidney transplant clinical trials. Although the current efficacy failure endpoint has typically shown the noninferiority of therapeutic regimens, the iBOX Scoring System can be used to demonstrate the superiority of a new immunosuppressive therapy compared to the standard of care from 6 months to 24 months posttransplant in pivotal or exploratory drug therapeutic studies.

Longitudinal estimated glomerular filtration rate (eGFR) modeling in long-term renal function to inform clinical trial design in kidney transplantation

Kidney transplantation is the preferred treatment for individuals with end-stage kidney disease. From a modeling perspective, our understanding of kidney function trajectories after transplantation remains limited. Current modeling of kidney function post-transplantation is focused on linear slopes or percent decline and often excludes the highly variable early timepoints post-transplantation, where kidney function recovers and then stabilizes. Using estimated glomerular filtration rate (eGFR), a well-known biomarker of kidney function, from an aggregated dataset of 4904 kidney transplant patients including both observational studies and clinical trials, we developed a longitudinal model of kidney function trajectories from time of transplant to 6 years post-transplant. Our model is a nonlinear, mixed-effects model built in NONMEM that captured both the recovery phase after kidney transplantation, where the graft recovers function, and the long-term phase of stabilization and slow decline. Model fit was assessed using diagnostic plots and individual fits. Model performance, assessed via visual predictive checks, suggests accurate model predictions of eGFR at the median and lower 95% quantiles of eGFR, ranges which are of critical clinical importance for assessing loss of kidney function. Various clinically relevant covariates were also explored and found to improve the model. For example, transplant recipients of deceased donors recover function more slowly after transplantation and calcineurin inhibitor use promotes faster long-term decay. Our work provides a generalizable, nonlinear model of kidney allograft function that will be useful for estimating eGFR up to 6 years post-transplant in various clinically relevant populations.

American Society of Transplant Surgeons recommendations on best practices in donation after circulatory death organ procurement

The American Society of Transplant Surgeons supports efforts to increase the number of organs that are critically needed for patients desperately awaiting transplantation. In the United States, transplantation using organs procured from donation after circulatory death (DCD) donors has continued to increase in number. Despite these increases, substantial variability in the utilization and practices of DCD transplantation still exists. To improve DCD organ utilization, it is important to create a set of best practices for DCD recovery. The following recommendations aim to provide guidance on contemporary issues surrounding DCD organ procurement in the United States. A work group was composed of members of the American Society of Transplant Surgeon Scientific Studies Committee and the Thoracic Organ Transplantation Committee. The following topics were identified by the group either as controversial or lacking standardization: prewithdrawal preparation, definition of donor warm ischemia time, DCD surgical technique, combined thoracic and abdominal procurements, and normothermic regional perfusion. The proposed recommendations were classified on the basis of the grade of available evidence and the strength of the recommendation. This information should be valuable for transplant programs as well as for organ procurement organizations and donor hospitals as they develop robust DCD donor procurement protocols.

Automated scoring of total inflammation in renal allograft biopsies

BACKGROUND

Computer-assisted scoring is gaining prominence in the evaluation of renal histology; however, much of the focus has been on identifying larger objects such as glomeruli. Total inflammation impacts graft outcome, and its quantification requires tools to identify objects at the cellular level or smaller. The goal of the current study was to use CD45 stained slides coupled with image analysis tools to quantify the amount of non-glomerular inflammation within the cortex.

METHODS

Sixty renal transplant whole slide images were used for digital image analysis. Multiple thresholding methods using pixel intensity and object size were used to identify inflammation in the cortex. Additionally, convolutional neural networks were used to separate glomeruli from other objects in the cortex. This combined measure of inflammation was then correlated with rescored Banff total inflammation classification and outcomes.

RESULTS

Identification of glomeruli on biopsies had high fidelity (mean pixelwise dice coefficient of .858). Continuous total inflammation scores correlated well with Banff rescoring (maximum Pearson correlation .824). A separate set of thresholds resulted in a significant correlation with alloimmune graft loss.

CONCLUSIONS

Automated scoring of inflammation showed a high correlation with Banff scoring. Digital image analysis provides a powerful tool for analysis of renal pathology, not only because it is reproducible and can be automated, but also because it provides much more granular data for studies.

Sodium-glucose cotransporter 2 inhibitors for treatment of diabetes mellitus after kidney transplantation

INTRODUCTION

Diabetes mellitus in kidney transplant recipients is a risk factor for cardiovascular events and premature death. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are increasingly used in nontransplant populations to improve diabetes control and cardiovascular and renal benefits. Limited literature exists regarding the safety and efficacy of these agents in renal transplant recipients.

METHODS

We retrospectively reviewed all kidney transplant recipients within our health system who were prescribed a SGLT2i after transplantation for diabetes. The safety, tolerability, and effectiveness of SGLT2i were analyzed.

RESULTS

Thirty-nine kidney transplant recipients were initiated on SGLT2i therapy, twenty-seven of which remained on therapy for at least 1 year. Ten (25%) patients experienced an adverse event while on a SGLT2i, with urinary tract infections (UTI) being the most common. Seventeen patients (43%) discontinued the SGLT2i at the time of chart review, most commonly due to cost and kidney function decline. The median [IQR] hemoglobin A1c (HbA1c) at SGLT2i initiation of 8.4% [7.8-9.2] decreased to 7.5% [6.8-8.0%] after 3 months and 7.5% [6.5-7.9] after 12 months. No meaningful change in kidney function or tacrolimus exposure was observed.

CONCLUSION

SGLT2i may be a safe and effective treatment for diabetes in kidney transplant recipients. Cost is a barrier to SGLT2i therapy, and UTIs were the most frequently encountered adverse events in this cohort. More studies are needed to understand the safety profile and determine the effect of SGLT2i on diabetes-related comorbidities among kidney transplant recipients.

Kidney Transplantation in Patients With Monoclonal Gammopathy of Renal Significance (MGRS)-Associated Lesions: A Case Series

RATIONALE & OBJECTIVE

Data on kidney transplantation outcomes among patients with monoclonal gammopathy of renal significance (MGRS) are lacking.

STUDY DESIGN

Case series of patients with MGRS, some of whom received clone-directed therapies before kidney transplantation.

SETTING & PARTICIPANTS

28 patients who underwent kidney transplantation from 1987 through 2016 after diagnosis with MGRS-associated lesions including light-chain deposition disease (LCDD), C3 glomerulopathy with monoclonal gammopathy (C3G-MG), and light-chain proximal tubulopathy (LCPT).

FINDINGS

Of the 19 patients with LCDD, 10 were treated before kidney transplantation and 9 were treatment-naive. Among the treated patients with LCDD, 3 (30%) experienced histologic recurrence, 2 (20%) grafts failed, and 2 (20%) died during a median follow-up of 70 (range, 3-162) months after transplant. In the treatment-naive LCDD group, 8 (89%) had histologic recurrence, 6 (67%) grafts failed, and 4 (44%) patients died during a median follow-up of 60 (range, 35-117) months. Of the 5 patients who had a complete response before transplant, none died, and only 1 experienced graft failure, 162 months after transplant. Of 5 patients with C3G-MG, 3 were treatment-naive before transplant. Both patients who were treated before transplant had histologic recurrence, and 1 experienced graft failure and died. Among the 3 patients with treatment-naive C3G-MG, histologic recurrence occurred in all, and graft loss and death were observed in 2 and 1, respectively. In the LCPT group (n=4), histologic recurrence was observed in all 3 patients who did not receive clone-directed therapies before transplant, and 2 of these patients died, 1 with a functioning kidney. The 1 patient with LCPT who received therapy before transplant did not have histologic recurrence or graft loss and survived.

LIMITATIONS

Small sample size, nonstandardized clinical management, retrospective design.

CONCLUSIONS

Recurrence is very common in all MGRS-associated lesions after kidney transplant. Achieving a complete hematologic response may reduce the risks of recurrence, graft loss, and death. More studies are needed to determine the effects of hematologic response on outcomes for each MGRS-associated lesion.

Improving Clinical Trials for Anticomplement Therapies in Complement-Mediated Glomerulopathies: Report of a Scientific Workshop Sponsored by the National Kidney Foundation

Blocking the complement system as a therapeutic strategy has been proposed for numerous glomerular diseases but presents myriad questions and challenges, not the least of which is demonstrating efficacy and safety. In light of these potential issues and because there are an increasing number of anticomplement therapy trials either planned or under way, the National Kidney Foundation facilitated an all-virtual scientific workshop entitled "Improving Clinical Trials for Anti-Complement Therapies in Complement-Mediated Glomerulopathies." Attended by patient representatives and experts in glomerular diseases, complement physiology, and clinical trial design, the aim of this workshop was to develop standards applicable for designing and conducting clinical trials for anticomplement therapies across a wide spectrum of complement-mediated glomerulopathies. Discussions focused on study design, participant risk assessment and mitigation, laboratory measurements and biomarkers to support these studies, and identification of optimal outcome measures to detect benefit, specifically for trials in complement-mediated diseases. This report summarizes the discussions from this workshop and outlines consensus recommendations.

Current Approaches to Desensitization in Solid Organ Transplantation

Major advancements in the development of HLA antibody detection techniques and our understanding of the outcomes of solid organ transplant in the context of HLA antibody have occurred since the relevance of sensitization was first recognized nearly 50 years ago. Additionally, kidney paired donation programs (KPD) have become widespread, deceased donor allocation policies have changed, and several new therapeutic options have become available with promise to reduce HLA antibody. In this overview we aim to provide thoughtful guidance about when desensitization in kidney transplantation should be considered taking into account the outcomes of HLA incompatible transplantation. Novel therapeutics, desensitization endpoints, and strategies for future study will also be discussed. While most of our understanding about desensitization comes from studying kidney transplant candidates and recipients, many of the concepts discussed can be easily applied to desensitization in all of solid organ transplantation.

Estimating alloantibody levels in highly sensitized renal allograft candidates: Using serial dilutions to demonstrate a treatment effect in clinical trials

Small reductions in calculated panel-reactive antibody (cPRA) are associated with increased kidney transplantation in 100% cPRA patients. However, the high level of antibody in these patients is such that desensitization may reduce antibody but not cPRA, thus the cPRA change on undiluted serum with desensitization is an insensitive measure of effectiveness. We evaluated cPRA reduction, calculated per antibody titer, as a desensitization trial endpoint. To accomplish this, two serum samples from 20 kidney transplant candidates with cPRA ≥99.9% (100%) were obtained and serially diluted in triplicate to determine the titer of individual human leukocyte antigen (HLA) antibody specificities. CPRA was computed per dilution to identify the titer at which cPRA drops below 98%. Inter- and intra-assay variability and changes overtime were determined. The dilution needed to reach a cPRA <98% was within 1 titer for replicates from the same sample, with 90% (36/40) concordance. This indicates that only changes >2 titers can be deemed clinically meaningful. The median (IQR) titer difference was 0 (0-1) from baseline to follow-up within 12 months. The cPRA per titer also risk-stratified candidates for trial inclusion. In conclusion, determining the cPRA per titer is a reliable approach to simplify complex antibody data and an ideal endpoint for desensitization trials.

Chronic graft-versus-host disease in pancreas after kidney transplant recipients - An unrecognized entity

Graft-versus-host disease (GVHD), a common complication after peripheral blood stem cell or bone marrow transplantation, rarely occurs in kidney and pancreas transplant recipients. The true incidence may be confounded by the rarity of the disorder, with a resultant lack of appreciation of the diagnosis as a potential cause of common clinical manifestations such as cytopenias and immune dysfunction. Reports of GVHD in kidney and pancreas transplant recipients almost uniformly describe patients in the early posttransplant period (days to months) with the typical manifestations of acute GVHD involving the skin, liver, and intestines. In contrast, reports of solid organ transplant recipients with clinical features more consistent with chronic GVHD (cGVHD) are lacking, raising concern of underrecognition of this severe complication. Occurrence later after transplant may be even more likely to result in lack of recognition. We report 2 cases of possible cGVHD occurring in recipients of pancreas after kidney transplantation, which were diagnosed at 5.5 and 42 months after pancreas transplant. Both patients presented with severe pancytopenia, multiple opportunistic infections, and features suggestive of cGVHD. Transplant professionals should be aware of the possibility of acute and cGVHD in pancreas after kidney transplant recipients and be able to recognize the clinical manifestations.

Mesangial expansion at 5 years predicts death and death-censored graft loss after renal transplantation

Death with a functioning graft and death-censored renal allograft failure remain major problems for which effective preventative protocols are lacking. The retrospective cohort study aimed to determine whether histologic changes on a 5-year surveillance kidney biopsy predict adverse outcomes after transplantation in recipients who had: both Type 2 diabetes (T2DM) and obesity (BMI ≥ 30 kg/m² ) at the time of transplantation (T2DM/Obesity, n = 75); neither (No T2DM/No obesity, n = 78); No T2DM/Obesity (n = 41), and T2DM/No obesity (n = 47). On 5-year biopsies, moderate-to-severe mesangial expansion was more common in the T2DM/Obesity group (Banff mm score ≥2 = 49.3%; Tervaert classification MS ≥ 2b = 26.7%) compared to the other groups (p < .001 for both scores). Risk factors included older age, higher BMI, HbA1C, and triglycerides at 1-year post-transplant. Moderate-to-severe mesangial expansion correlated with death with function (HR 1.74 (1.01, 2.98), p = .045 Banff and 1.89 (1.01, 3.51) p = .045 Tervaert) and with death-censored graft loss (HR 3.2 (1.2, 8.8), p = .02 Banff and HR 3.8 (1.3, 11.5), p = .01 Tervaert) over a mean of 11.6 years of recipient follow-up post-transplant. These data suggest that mesangial expansion in recipients with T2DM and obesity may reflect systemic vascular injury and might be a novel biomarker to predict adverse outcomes post renal transplant.

Continuous glucose monitoring to assess glycemic control in the first 6 weeks after pancreas transplantation

BACKGROUND

Current therapy for Type 1 diabetes (T1D) is characterized by significant glucose variability (GV). Pancreas transplantation (PT) is performed in certain T1D patients with and without end-stage renal disease. To date, GV has been examined to a limited extent after PT.

METHODS

We investigated GV using continuous glucose monitoring (CGM) 3-6 weeks after PT.

RESULTS

Eleven patients had simultaneous kidney pancreas transplantation (SPK), nine pancreas after kidney (PAK), and six pancreas transplantation alone (PTA). Mean CGM showed no difference between SPK, 126.5 ± 13.9, PAK 119.9 ± 12.8, and PTA 131.1 ± 29 mg/dL (P value .6). Percentage of time in range (TIR, 70-180 mg/dL) was 92% for SPK, 93.4% in PAK, and 88.5% in PTA with only 0.3%, 1.5%, and 0.3% of time <70 mg/dL. Percentage >180 mg/dL was 7.9% for SPK, 4.9% PAK, and 11% in PTA. Other measures of GV were similar in the three cohorts. In six patients, CGM was performed before and after PT and improved significantly. GV was also better compared with a matched cohort of T1D patients.

CONCLUSIONS

All 3 types of PT resulted in excellent glucose control 3-6 weeks post-procedure. CGM outcomes represent an important objective outcome after PT.

Daratumumab in Sensitized Kidney Transplantation: Potentials and Limitations of Experimental and Clinical Use

BACKGROUND

Donor-specific antibodies are associated with increased risk of antibody-mediated rejection and decreased allograft survival. Therefore, reducing the risk of these antibodies remains a clinical need in transplantation. Plasma cells are a logical target of therapy given their critical role in antibody production.

METHODS

To target plasma cells, we treated sensitized rhesus macaques with daratumumab (anti-CD38 mAb). Before transplant, we sensitized eight macaques with two sequential skin grafts from MHC-mismatched donors; four of them were also desensitized with daratumumab and plerixafor (anti-CXCR4). We also treated two patients with daratumumab in the context of transplant.

RESULTS

The animals treated with daratumumab had significantly reduced donor-specific antibody levels compared with untreated controls (57.9% versus 13% reduction; P<0.05) and prolonged renal graft survival (28.0 days versus 5.2 days; P<0.01). However, the reduction in donor-specific antibodies was not maintained because all recipients demonstrated rapid rebound of antibodies, with profound T cell-mediated rejection. In the two clinical patients, a combined heart and kidney transplant recipient with refractory antibody-mediated rejection and a highly sensitized heart transplant candidate, we also observed a significant decrease in class 1 and 2 donor-specific antibodies that led to clinical improvement of antibody-mediated rejection and to heart graft access.

CONCLUSIONS

Targeting CD38 with daratumumab significantly reduced anti-HLA antibodies and anti-HLA donor-specific antibodies in a nonhuman primate model and in two transplant clinical cases before and after transplant. This supports investigation of daratumumab as a potential therapeutic strategy; however, further research is needed regarding its use for both antibody-mediated rejection and desensitization.

SUN-133 Glycemic Control in T1D Subjects before and after Pancreas Transplantation

Type 1 diabetes (T1D) is characterized by significant glycemic variability (GV) with current insulin based therapeutic options. Pancreas transplantation (PT) is performed in certain individuals with T1D with and without and end-stage renal disease. To date, GV before and after PT has been examined to a limited extent and the optimal times to assess glucose control after PT has not been evaluated. We investigated GV using continuous glucose monitoring (CGM) prior to PT and 3-6 weeks after PT in 6 patients with T1D. Participants wore CGM for about 4-7 days. Glucose control was measured for the same 6 patients with T1D before PT (age 36.8 ± 9.8 years, F/M 3/3, HbA1c 8.2 ± 0.9%, BMI 26.8 ± 4.8 kg/m² and creatinine 3 ± 2.3 mg/dl) and 3-6 weeks after PT (HbA1c 6.8 ± 1.3%, BMI 25.5 ± 5 kg/m² and creatinine 1.5 ± 0.7 mg/dl). The CGM data were analyzed using measures of glucose control as recommended by the recent consensus report. Measurements include standard measures such as mean ± SD and state of the art CGM related statistics such as % time spent in various glucose ranges and indices of hypo and hyperglycemia. Mean CGM glucose improved after PT compared to before PT (136.5 ± 27.3 vs 199.5 ± 36.5, P value 0.01). The percentage of time spent within ranges 70-180mg/dl and 70 -140mg/dl after PT was 84.8 ± 13.7% and 61± 27.3% compared to before PT 42.5 ± 15.4% and 21.5 ± 10.1 (P value 0.004 and 0.02 respectively). Significant change was noticed in duration of hyperglycemia as percentage of time spent above 180mg and 250mg/dl were higher prior to PT (55 ± 17.2 and 23.8 ± 17.4% respectively) compared to after PT 14.3 ± 14.1% and 2.2 ± 3% respectively (P value 0.006 and 0.03). Hypoglycemic episodes during CGM were observed in patients before but not after PT. 4 patients had episodes of hypoglycemia <54mg/dl before PT and total percentage of time < 54mg/dl was 0.7 ± 0.8 and < 70mg/dl 2.7 ± 2.7 before PT. Patients after PT showed improvement in hypoglycemia with percentage time spent <70mg/dl 0.7 ± 0.5% (P value 0.1) and no time<54mg/dl (P value 0.1) Similar results were observed when data were analyzed for daytime and nighttime glucose control. However, hypoglycemia was observed more during nighttime (12-6am) than during daytime before PT (3.5 ± 3.2 vs 2.6 ± 6.4) and after PT (2.2 ± 2.6 vs 0.9 ± 1.1). Conclusion: CGM provides a reliable method of monitoring glucose control after pancreas transplantation. Overall glucose control measures were better after PT even with a sample size of 6 subjects. CGM outcomes represent an important objective outcome of glucose control after PT and require inclusion in prospective studies of PT with appropriate times for measurement to be investigated further.

A method to reduce variability in scoring antibody-mediated rejection in renal allografts: implications for clinical trials - a retrospective study

Poor reproducibility in scoring antibody-mediated rejection (ABMR) using the Banff criteria might limit the use of histology in clinical trials. We evaluated the reproducibility of Banff scoring of 67 biopsies by six renal pathologists at three institutions. Agreement by any two pathologists was poor: 44.8-65.7% for glomerulitis, 44.8-67.2% for peritubular capillaritis, and 53.7-80.6% for chronic glomerulopathy (cg). All pathologists agreed on cg0 (n = 20) and cg3 (n = 9) cases, however, many disagreed on scores of cg1 or cg2. The range for the incidence of composite diagnoses by individual pathologists was: 16.4-22.4% for no ABMR; 17.9-47.8% for active ABMR; and 35.8-59.7% for chronic, active antibody-mediated rejection (cABMR). A "majority rules" approach was then tested in which the scores of three pathologists were used to reach an agreement. This increased consensus both for individual scores (ex. 67.2-77.6% for cg) and for composite diagnoses (ex. 74.6-86.6% cABMR). Modeling using these results showed that differences in individual scoring could affect the outcome assessment in a mock study of cABMR. We conclude that the Banff schema has high variability and a majority rules approach could be used to adjudicate differences between pathologists and reduce variability in scoring in clinical trials.

The Banff 2017 Kidney Meeting Report: Revised diagnostic criteria for chronic active T cell-mediated rejection, antibody-mediated rejection, and prospects for integrative endpoints for next-generation clinical trials

The kidney sessions of the 2017 Banff Conference focused on 2 areas: clinical implications of inflammation in areas of interstitial fibrosis and tubular atrophy (i-IFTA) and its relationship to T cell-mediated rejection (TCMR), and the continued evolution of molecular diagnostics, particularly in the diagnosis of antibody-mediated rejection (ABMR). In confirmation of previous studies, it was independently demonstrated by 2 groups that i-IFTA is associated with reduced graft survival. Furthermore, these groups presented that i-IFTA, particularly when involving >25% of sclerotic cortex in association with tubulitis, is often a sequela of acute TCMR in association with underimmunosuppression. The classification was thus revised to include moderate i-IFTA plus moderate or severe tubulitis as diagnostic of chronic active TCMR. Other studies demonstrated that certain molecular classifiers improve diagnosis of ABMR beyond what is possible with histology, C4d, and detection of donor-specific antibodies (DSAs) and that both C4d and validated molecular assays can serve as potential alternatives and/or complements to DSAs in the diagnosis of ABMR. The Banff ABMR criteria are thus updated to include these alternatives. Finally, the present report paves the way for the Banff scheme to be part of an integrative approach for defining surrogate endpoints in next-generation clinical trials.

Impact of CXCR4/CXCL12 Blockade on Normal Plasma Cells In Vivo

Plasma cells (PCs) are a major source of alloantibody in transplant patients and are resistant to current therapy. Because receptor-ligand interactions in stromal microenvironments play important roles in the localization, development, and survival of normal PCs, we hypothesized that interfering with CXCR4/CXCL12 interactions with plerixafor might cause PC depletion and enhance the efficacy of the proteasome inhibitor bortezomib. PCs in mouse spleen, bone marrow, and peripheral blood demonstrated CXCR4 expression. We then treated with plerixafor in doses ranging from 240 μg/kg in a single dose to a 1-mg/kg daily dose for 10 days. CXCR4/CXCL12 blockade with plerixafor resulted in increased mobilization of PCs into the peripheral blood. Splenectomy completely abrogated this effect, suggesting that all plerixafor-mobilized cells were from the spleen. The total number of PCs in the spleen and marrow remained constant despite treatment with plerixafor. Bortezomib caused a reduction in PCs, but adding plerixafor did not increase killing. We conclude that CXCR4/CXCL12 interactions are important for the retention of a subpopulation of PCs in the spleen, but this interaction has minimal effect on PCs in the marrow. The lack of enhancement of bortezomib-mediated depletion suggests that factors other than CXCR4/CXCL12 interactions are responsible for drug resistance.

Minimal effect of bortezomib in reducing anti-pig antibodies in human leukocyte antigen-sensitized patients: a pilot study

BACKGROUND

Bortezomib, a proteasome inhibitor used to treat multiple myeloma, has been administered (± plasma exchange ± intravenous immunoglobulin [IVIg]) in attempts to reduce antibodies against human leukocyte antigens (HLA) in sensitized patients undergoing organ transplantation. To our knowledge, bortezomib has not been investigated for its effect on natural anti-pig antibodies. If bortezomib could reduce the production of anti-pig antibodies, this would likely be beneficial to the outcome of pig organ grafts in primates.

METHODS

Nine patients received bortezomib either to reduce anti-HLA antibody levels before organ allotransplantation or to treat antibody-mediated rejection. Patients at the Mayo Clinic (Group 1; n = 4) received bortezomib alone, whereas at the UPMC (Group 2; n = 5), this was combined with plasmaphereses ± IVIg in some cases. Anti-pig IgM and IgG levels against wild-type (WT) and α1,3-galactosyltransferase gene knockout (GTKO) pig aortic endothelial cells (flow cytometry-relative mean fluorescence intensity) and anti-Gal IgM and IgG (ELISA-OD480 nm ) were measured pre- and post-bortezomib therapy.

RESULTS

Mean anti-pig IgM levels were 11.2 (WT) and 1.9 (GTKO) pre-bortezomib treatment and 9.4 (WT: P = 0.02) and 1.7 (GTKO: P = 0.33) post-bortezomib treatment, respectively. Mean anti-pig IgG levels were 4.3 (WT) and 1.5 (GTKO) pre-bortezomib treatment and 3.6 (WT: P = 0.21) and 1.4 (GTKO: P = 0.20) post-bortezomib treatment, respectively. Mean anti-Gal IgM and IgG levels were 0.7 and 1.1, respectively, pre-treatment, and 0.6 (P = 0.03) and 1.1 (NS), respectively, post-treatment. When the data were analyzed in Groups 1 and 2 separately, there were no significant differences between the pre- and post-bortezomib levels of anti-pig, anti-non-Gal, or anti-Gal IgM or IgG.

CONCLUSIONS

From this limited study, we conclude that bortezomib might reduce anti-Gal IgM levels in primates, but, in this respect alone, is unlikely to have any significant effect on the outcome of GTKO pig organ transplantation.

Inter and intra laboratory concordance of HLA antibody results obtained by single antigen bead based assay

Single antigen bead based assays (SAB) to identify antibodies to HLA are marketed as a qualitative test, however often used as a quantitative test as the results provide mean fluorescence intensity (MFI) which is found to correlate with the strength/avidity of the antibody. We studied the between and within laboratory variability in performing the SAB from one manufacturer. Ten samples were tested at four laboratories according to the manufacturer's suggested protocol. Additionally same samples were tested on four consecutive days in one laboratory. All tests were performed using the same lot of beads and secondary antibody. Results were classified as positive at four different MFI cutoffs: 1000, 5000, 8000 and 10,000. MFI values across and within the laboratory were compared in a pair-wise fashion with Pearson's correlations. Overall concordance for Class-I was 97% between laboratories and 98% within laboratory at all cutoffs. Pair-wise Pearson correlation between laboratories was 0.989-0.99, while within laboratory it was 0.998-0.999. For Class-II, overall concordance between and within laboratory was 98%. Pair-wise Pearson correlation between laboratories was 0.991-0.997, while within laboratory it was 0.997-0.999. There is good correlation between laboratories and within laboratory using the same manufacturer, same lot and same protocol while performing SAB.

Relationship between FKBP5 polymorphisms and depression symptoms among kidney transplant recipients

BACKGROUND

Several polymorphisms in FK506 Binding Protein gene (FKBP5) and a history of child abuse have been shown to be associated with an increased risk for posttraumatic stress disorder (PTSD). It has also been demonstrated that the same polymorphisms of FKBP5 are associated with increased recurrence of depressive episodes and rapid response to antidepressant treatment. However, there are only limited numbers of studies replicating the polymorphisms as vulnerability factors for the development of mental illnesses, such as PTSD and depression after stressful life event, especially with a specific incidence, such as kidney transplant surgery.

METHODS

A retrospective analysis was conducted using the electronic medical records of 131 adult kidney transplant recipients. Depression severity after kidney transplantation was measured by PHQ-9, and stored blood was genotyped for variants in the Serotonin Transporter (SLC6A4), Brain-Derived Neurotrophic Factor, Catecholamine-O-Methyltransferase, Corticotropin-Releasing Hormone Receptor, and FKBP5 genes. Spearman correlations were used to test for association between genetic variants and depression severity.

RESULTS

The rare alleles at three out of four SNPs in FKBP5 (rs1360780, rs9296158, and rs9470080) were associated with increased PHQ-9 scores (P<.05), whereas the last FKBP5 SNP (rs3800373) showed a trend of association (P<.10). All four FKBP5 SNPs are in strong linkage disequilibrium. Although in a subgroup of Caucasian non-Hispanic subjects the association was not statistically significant, the direction of association was consistent with that observed in the entire sample as well as in previous studies. Polymorphisms in genes other than FKBP5 were not associated with PHQ-9 scores.

CONCLUSIONS

Polymorphisms in FKBP5 may be associated with higher depression scores in kidney transplant recipients.

Type-II superlattice dual-band LWIR imager with M-barrier and Fabry-Perot resonance

We report a high performance long-wavelength IR dual-band imager based on type-II superlattices with 100% cutoff wavelengths at 9.5 μm (blue channel) and 13 μm (red channel). Test pixels reveal background-limited behavior with specific detectivities as high as ~5×10¹¹ Jones at 7.9 μm in the blue channel and ~1×10¹¹ Jones at 10.2 μm in the red channel at 77 K. These performances were attributed to low dark currents thanks to the M-barrier and Fabry-Perot enhanced quantum efficiencies despite using thin 2 μm absorbing regions. In the imager, the high signal-to-noise ratio contributed to median noise equivalent temperature differences of ~20 milli-Kelvin for both channels with integration times on the order of 0.5 ms, making it suitable for high speed applications.

Blood Pressure and Renal Function after Kidney Donation from Hypertensive Living Donors

BACKGROUND

Rising numbers of patients reaching end-stage kidney disease intensify the demand for expansion of the living-kidney-donor pool. On the basis of low risk in white donors with essential hypertension, our transplant center undertook a structured program of accepting hypertensive donors if kidney function and urine protein were normal. This study reports outcomes of hypertensive donors 1 year after kidney donation.

METHODS

We studied detailed measurements of blood pressure (oscillometric, hypertensive therapy nurse [RN], and ambulatory blood pressure monitoring [ABPM]), clinical, and renal characteristics (iothalamate glomerular filtration rate [GFR], urine protein, and microalbumin) in 148 living kidney donors before and 6 to 12 months after nephrectomy. Twenty-four were hypertensive (awake ABPM>135/85 mm Hg and clinic/RN BP>140/90 mm Hg) before donation.

RESULTS

After 282 days, normotensive donors had no change in awake ABPM pressure (pre 121 +/- 1/75 +/- 2 vs. post 120 +/- 1/ 5 +/- 1 mm Hg), whereas BP in hypertensive donors fell with both nonpharmacologic and drug therapy (pre 142 +/- 3/85 +/- 2 to post 132 +/- 2/80 +/- 1 mm Hg, P<.01). Hypertensive donors were older (53.4 vs. 41.4 years, P<.001) and had lower GFR after kidney donation (61 +/- 2 vs. 68 +/- 1 mL/min/1.73m, P<.01). After correction for age, no independent BP effect was evident for predicting GFR either before or after nephrectomy. Urine protein and microalbumin did not change in either group after donor nephrectomy.

CONCLUSIONS

Our results indicate that white subjects with moderate, essential hypertension and normal kidney function have no adverse effects regarding blood pressure, GFR, or urinary protein excretion during the first year after living kidney donation. Although further studies are essential to confirm long-term safety, these data suggest that selected hypertensive patients may be accepted for living kidney donation.

Blood pressure evaluation among older living kidney donors

With more patients reaching end-stage renal disease, the demand for living kidney donation is increasing rapidly. Many potential donors are now in older age groups. The effects of increasing BP with age and the measurement criteria for hypertension in this group are not well defined. A total of 238 potential donors between 18 and 72 yr of age were prospectively studied, with a comparison of "clinic" BP values measured in the outpatient clinic with an oscillometric recorder (Dinamap; Critikon), ambulatory BP monitoring (ABPM) findings, and standardized BP values determined by nurses using American Heart Association criteria. Renal function was evaluated on the basis of iothalamate clearance (GFR) and urinary protein and microalbumin excretion. Ninety-six percent of subjects were Caucasian. All subjects exhibited normal GFR and urinary protein excretion. Three age groups were defined (group I, </=35 yr, n = 64; group II, 36 to 49 yr, n = 109; group III, >/= 50 yr, n = 65). BP increased with age, as determined with all methods. Subjects >/= 50 yr of age exhibited the highest clinic readings (145 +/- 2/83 +/- 1 mmHg, compared with 129 +/- 2/76 +/- 1 mmHg for group I, P < 0.01). Awake ABPM and nurse-determined BP measurements were lower than clinic readings, including those for group III (131 +/- 2/80 +/- 1 mmHg, compared with 145 +/- 2/83 +/- 1 mmHg in the clinic, P < 0.001). With the use of systolic BP values of >140 mmHg and/or diastolic BP values of >90 mmHg, 36.7% of subjects were initially considered hypertensive; this proportion decreased to 11% overall with awake ABPM findings (>135/85 mmHg). Measurement variability (SD in ABPM) and the effects of misclassification were greatest for donors >/= 50 yr of age. Multivariate regression indicated that GFR of both donors and recipients decreased with age, but regression identified no independent effect of BP. Recipient outcomes for up to 2 yr were equally good for donor kidneys considered normotensive or hypertensive on the basis of clinic BP measurements. These data indicate that higher arterial BP with age can lead to misclassification of many older living kidney donors. Sixty-two subjects with excellent kidney function were misclassified as hypertensive with clinic oscillometric measurements alone. Detailed evaluations of ABPM findings, GFR, and urinary protein levels are warranted for Caucasian subjects with high clinic BP readings who are otherwise suitable potential donors.

Randomized trial of tacrolimus + mycophenolate mofetil or azathioprine versus cyclosporine + mycophenolate mofetil after cadaveric kidney transplantation: results at three years

METHODS

Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus (TAC) + mycophenolate mofetil (MMF), TAC + azathioprine (AZA), or cyclosporine (Neoral; CsA) + MMF. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function (DGF). Patients were followed-up for 3 years.

RESULTS

The results at 3 years corroborate and extend the findings of the 2-year results. Patients with DGF treated with TAC+MMF experienced an increase in 3-year allograft survival compared with patients receiving CsA+MMF (84.1% vs. 49.9%, P=0.02). Patients randomized to either treatment arm containing TAC exhibited numerically superior kidney function when compared with CsA. During the 3 years, new-onset insulin dependence occurred in 6, 3, and 11 patients in the TAC+MMF, CsA+MMF, and TAC+AZA treatment arms, respectively. Furthermore, patients randomized to TAC+MMF received significantly lower doses of MMF as compared with those who received CsA+MMF.

CONCLUSION

All three immunosuppressive regimens provided excellent safety and efficacy. However, the best results overall were achieved with TAC+MMF. The combination may provide particular benefit to kidney allograft recipients with DGF. In patients who experienced DGF, graft survival was better at 3 years in those patients receiving TAC in combination with either MMF or AZA as compared with the patients receiving CsA with MMF.

Gene expression during acute allograft rejection: novel statistical analysis of microarray data

High-throughput microarrays promise a comprehensive analysis of complex biological processes, yet their applicability is hampered by problems of reproducibility and data management. The current study examines some of the major questions of microarray use in a well-described model of allograft rejection. Using the Brown Norway to Lewis heterotopic heart transplant model, highly purified RNA was isolated from cardiac tissue at postoperative days (POD) 3, 5 and 7 and hybridized onto Affymetrix U34A microarrays. Using the log average ratio (LAR), changes in gene expression were monitored at each timepoint and p-values generated through statistical analysis. Microarray data were verified for 13 significant transcripts using RT-PCR. Of the 8800 transcripts studied, 2864 were increased on POD 3, 1418 on POD 5 and 2745 on POD 7. Verifying previous studies, many up-regulated genes appeared to be associated with the inflammatory process and graft infiltrating cells. Down-regulated transcripts included many novel molecules such as SC1 and decorin. LAR analysis provides a useful approach to analyze microarray data. Results were reproducible and correlated well with both RT-PCR and prior studies. Most importantly, these results provide new insights into the pathogenesis of acute rejection and suggest new molecules for future studies.

Randomized trial of tacrolimus plus mycophenolate mofetil or azathioprine versus cyclosporine oral solution (modified) plus mycophenolate mofetil after cadaveric kidney transplantation: results at 2 years

BACKGROUND

A previous report described the 1-year results of a prospective, randomized trial designed to investigate the optimal combination of immunosuppressants in kidney transplantation. Recipients of first cadaveric kidney allografts were treated with tacrolimus+mycophenolate mofetil (MMF), cyclosporine oral solution (modified) (CsA)+MMF, or tacrolimus+azathioprine (AZA). Results at 1 year revealed that optimal efficacy and safety were achieved with a regimen containing tacrolimus+MMF. The present report describes results at 2 years.

METHODS

Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus+MMF, CsA+MMF, or tacrolimus+AZA. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function. Patients were followed up for 2 years.

RESULTS

The results at 2 years corroborate and extend the findings of the previous report. Patients randomized to either treatment arm containing tacrolimus experienced improved kidney function. New-onset insulin dependence remained in four, three, and four patients in the tacrolimus+MMF, CsA+MMF, and tacrolimus+AZA treatment arms, respectively. Furthermore, patients with delayed graft function/acute tubular necrosis who were treated with tacrolimus+MMF experienced a 23% increase in allograft survival compared with patients receiving CsA+MMF (P=0.06). Patients randomized to tacrolimus+MMF received significantly lower doses of MMF compared with those administered CsA+MMF.

CONCLUSIONS

All three immunosuppressive regi-mens provided excellent safety and efficacy. How-ever, the best results overall were achieved with tacrolimus+MMF. The combination may provide particular benefit to kidney allograft recipients who develop delayed graft function/acute tubular necrosis. Renal function at 2 years was better in the tacrolimus treatment groups compared with the CsA group.

Randomized trial of tacrolimus (Prograf) in combination with azathioprine or mycophenolate mofetil versus cyclosporine (Neoral) with mycophenolate mofetil after cadaveric kidney transplantation

BACKGROUND

Our clinical trial was designed to investigate the optimal combination of immunosuppressants for renal transplantation.

METHODS

A randomized three-arm, parallel group, open label, prospective study was performed at 15 North American centers to compare three immunosuppressive regimens: tacrolimus + azathioprine (AZA) versus cyclosporine (Neoral) + mycophenolate mofetil (MMF) versus tacrolimus + MMF. All patients were first cadaveric kidney transplants receiving the same maintenance corticosteroid regimen. Only patients with delayed graft function (32%) received antilymphocyte induction. A total of 223 patients were randomized, transplanted, and followed for 1 year.

RESULTS

There were no significant differences in baseline demography between the three treatment groups. At 1 year the results are as follows: acute rejection 17% (95% confidence interval 9%, 26%) in tacrolimus + AZA; 20% (confidence interval 11%, 29%) in cyclosporine + MMF; and 15% (confidence interval 7%, 24%) in tacrolimus + MMF. The incidence of steroid resistant rejection requiring antilymphocyte therapy was 12% in the tacrolimus + AZA group, 11% in the cyclosporine + MMF group, and 4% in the tacrolimus + MMF group. There were no significant differences in overall patient or graft survival. Tacrolimus-treated patients had a lower incidence of hyperlipidemia through 6 months posttransplant. The incidence of posttransplant diabetes mellitus requiring insulin was 14% in the tacrolimus + AZA group, 7% in the cyclosporine + MMF and 7% in the tacrolimus + MMF groups.

CONCLUSIONS

All regimens yielded similar acute rejection rates and graft survival, but the tacrolimus + MMF regimen was associated with the lowest rate of steroid resistant rejection requiring antilymphocyte therapy.

Early steroid withdrawal in liver transplantation is safe and beneficial

This report reviews the literature and discusses steroid withdrawal after hepatic transplantation. Our experience with steroid withdrawal is highlighted. The hypothesis is that steroid withdrawal from liver transplant recipients is safe and beneficial. A review of the English literature yielded 16 reports with a total of 901 patients (749 adults and 152 children). Most reports were nonrandomized and uncontrolled. Only two reports were randomized, controlled trials; three reports featured early steroid withdrawal (</= 3 months); and one report featured very early steroid withdrawal (14 days). Steroid withdrawal was achieved in approximately 85% of the patients. Acute rejection was not significantly increased by steroid withdrawal; rates were 5% to 14% in uncontrolled trials and 7% versus 7% (late steroid withdrawal v control; P = not significant [NS]) and 4% versus 8% (early steroid withdrawal v control; P = NS) in controlled trials. Acute rejection rates after very early steroid withdrawal (14 days posttransplantation) were 42% to 46%, similar to or less than the 40% to 70% reported for steroid-containing regimens. Chronic rejection was not increased by steroid withdrawal; the rate was 3.9% in one uncontrolled trial and 0% versus 3% (early steroid withdrawal v control; P = NS) in one controlled trial. Patient and graft survival were not adversely affected. Steroid withdrawal was associated with reduced rates and better control of hypertension, reduced total cholesterol levels, reduced rate of posttransplantation diabetes mellitus, improved control of diabetes, and reduced rate of obesity. The aggregate experience with steroid withdrawal suggests it is safe, associated with improvement in several posttransplantation complications, and deserves broader clinical application.