Low incidence of kidney rejection after simultaneous kidney-pancreas transplantation after antithymocyte globulin induction and in the absence of corticosteroids: results of a prospective pilot study in 28 consecutive cases

A comprehensive update of the metabolic and toxicological considerations for immunosuppressive drugs used during pancreas transplantation

INTRODUCTION

Despite significant advancements in immunosuppressive regimens and surgical techniques, the prevalence of adverse events related to immunosuppression remains a major challenge affecting the long-term survival rates of pancreas and kidney allografts.

AREAS COVERED

This article presents a comprehensive review of the literature and knowledge (Jan/2012-Feb/2023) concerning glucose metabolism disorders and nephrotoxicity associated with tacrolimus and mammalian target of rapamycin inhibitors (mTORi). Novel signaling pathways potentially implicated in these adverse events are discussed. Furthermore, we extensively examine the findings from clinical trials evaluating the efficacy and safety of tacrolimus, mTORi, and steroid minimization.

EXPERT OPINION

Tacrolimus-based regimens continue to be the standard treatment following pancreas transplants. However, prolonged use of tacrolimus and mTORi may lead to hyperglycemia and nephrotoxicity. Understanding and interpreting experimental data, particularly concerning novel signaling pathways beyond calcineurin-NFAT and mTOR pathways, can offer valuable insights for therapeutic interventions to mitigate hyperglycemia and nephrotoxicity. Additionally, critically analyzing clinical trial results can identify opportunities for personalized safety-based approaches to minimize side effects. It is imperative to conduct randomized-controlled studies to assess the impact of mTORi use and steroid-free protocols on pancreatic allograft survival. Such studies will aid in tailoring treatment strategies for improved transplant outcomes.

Early corticosteroid avoidance in kidney transplant recipients receiving ATG-F induction: 5-year actual results of a prospective and randomized study

One hundred ninety-seven patients received anti-T-lymphocyte globulins Fresenius, mycophenolate mofetil and delayed cyclosporine, and were randomized to ≥6-month corticosteroids (+CS; n=99) or no CS (-CS; n=98). One- and five-year actual graft survival (censored for death) was 93.2% and 86.4% in the +CS group versus 94.9% and 89.8% in the -CS group (5-year follow-up, p=0.487). Freedom from clinical rejection was 86.9% and 81.8% versus 74.5% and 74.5% (p=0.144), respectively, at 1 and 5 years; 5-year freedom from biopsy-proven rejection was 88.9% versus 83.7% (p=0.227). More late first rejections occurred in the +CS group. Significantly lower 5-year graft survival in patients experiencing rejection was observed for +CS (55.6% vs. 92.0%; p=0.005) with 8/18 versus 2/25 graft losses. Renal function at 5 years was stable and comparable (median serum creatinine, 159 vs. 145 µmol/L; creatinine clearance, 53.5 vs. 56.6 mL/min). More +CS patients developed diabetes, dyslipidemia and malignancies. Rejections in -CS patients occurred early after transplantation and did not impair long-term renal function. In patients receiving CS, rejections occurred later and with a higher risk for subsequent graft failure. A similar and not inferior 5-year efficacy profile and a reduced morbidity were observed in CS-free patients compared to patients who received CS for at least 6 months.

Trends in immunosuppression after pancreas transplantation: what is in the pipeline?

PURPOSE OF REVIEW

To provide an overview of currently available immunosuppressive strategies and novel therapeutic developments in pancreas transplantation.

RECENT FINDINGS

From 1966 through 2012 more than 30 000 pancreas transplantations have been performed around the world with excellent patient and graft survival. However, drug-related side effects and toxicities remain to negatively affect long-term outcomes. At present, more than 90% of pancreas transplant recipients receive induction therapy with depleting or nondepleting antibodies. The most widely used maintenance protocols are based on tacrolimus and mycophenolate mofetil with early or delayed corticosteroid withdrawal. In case of documented side effects related to this standard protocol, several regimens are actively pursued to switch to mammalian target of rapamycin inhibitors as well as to attempt initial calcineurin inhibitor avoidance and immunosuppression minimization. In addition, the recent documented negative impact of donor-specific antibodies on pancreas transplantation outcome has resulted in new treatment protocols for antibody-mediated rejection including intravenous immunoglobulins, anti-CD20 antibodies and protease inhibitors.

SUMMARY

Implementation of novel therapeutic strategies and combination protocols to reduce or avoid drug toxicities and immune-related complications that are evaluated in prospective and randomized trials is requested to improve outcomes after pancreas transplantation.

Immunosuppression in simultaneous pancreas-kidney transplantation: progress to date

Simultaneous pancreas-kidney transplantation (SPKT) is the treatment of choice for patients with end-stage renal failure due to type 1 diabetes mellitus. With advances in surgical techniques and immunosuppression management, outcomes have improved, with current 1- and 10-year pancreas graft survival rates of 86% and 53%, respectively. Induction therapy with either alemtuzumab or rabbit antithymocyte globulin (rATG) in combination with a calcineurin inhibitor (CNI) and mycophenolate mofetil (MMF) or sirolimus appears to be safe and effective in the setting of rapid steroid withdrawal (RSW), with excellent graft survival and low rejection rates. There are no large randomized trials between alemtuzumab and rATG to determine whether one is better than the other. Anti-interleukin (IL)-2 receptor antibody induction and no induction in combination with a CNI, MMF or sirolimus, and prednisone have demonstrated excellent graft survival rates but are associated with a higher incidence of acute rejection. The efficacy of anti-IL-2 receptor antibodies or no induction in the setting of RSW is unproven. Both of the CNIs, ciclosporin and tacrolimus, are effective in preventing acute rejection in SPKT recipients; however, pancreas allograft survival may be better with tacrolimus. MMF is more effective than azathioprine in preventing acute rejection. Sirolimus appears to be effective in preventing acute rejection, but the combination of sirolimus with a CNI may accentuate the nephrotoxicity of the CNI. RSW with induction therapy is safe and effective in SPKT recipients, but longer follow-up data on outcomes are needed. Recent analysis of registry data shows that most transplant centres are using an induction agent followed by a combination of tacrolimus, MMF and corticosteroids in SPKT recipients.

Steroid avoidance or withdrawal for kidney transplant recipients

BACKGROUND

Steroid-sparing strategies have been attempted during the last two decades in order to avoid morbidity in kidney transplant recipients. Previous systematic reviews of steroid withdrawal after kidney transplantation have shown significant increases in acute rejection and an increase in graft failure rates. Steroid avoidance in kidney transplantation is increasingly attempted and the possible benefits or harms have never been a subject of a systematic review.

OBJECTIVES

To assess the safety and efficacy of steroid withdrawal or avoidance in patients receiving a kidney transplant.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE, references lists and abstracts from international transplantation society scientific meetings.

SELECTION CRITERIA

Randomised controlled studies (RCTs) of steroid avoidance or withdrawal were included providing that one treatment arm consisted in steroid avoidance or withdrawal and intention-to-treat rates of acute rejection and graft failure were clearly established after steroid avoidance or use or withdrawal or continuation. Observational studies were tabulated.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 30 RCTs (5949 participants). Steroid-sparing strategies showed no effect on mortality or graft loss including death. Patients on any steroid-sparing strategy showed a higher risk of graft loss excluding death than those with conventional steroid use (RR 1.23, 95% CI 1.00 to 1.52), especially in those not receiving MMF/Myf or everolimus (RR 1.70, 95% CI 1.00 to 2.90). Acute rejection was more frequent with a steroid-sparing strategy (RR 1.27, 95% CI 1.14 to 1.40) and more frequent after steroid withdrawal or avoidance when compared with standard steroid treatment when cyclosporin (CsA) was used. Steroid-sparing and withdrawal strategies showed benefits in reducing antihypertensive drug need, serum cholesterol, antihyperlipidaemic drug need, new-onset diabetes after transplantation (NODAT) requiring any treatment and cataracts. Steroid avoidance did not alter serum cholesterol, but was associated with less frequent NODAT requiring any treatment. Cardiovascular events were reduced with steroid avoidance. Reduced antihypertensive drug need and serum cholesterol were similar with CsA or tacrolimus (TAC). Reduced antihyperlipidaemic drug need was only evident with TAC, whereas the reduction in NODAT requiring any treatment was only evident with CsA. Infection was lower in steroid-sparing patients using CsA (RR 0.88, 95% CI 0.78 to 1.00). NODAT requiring any treatment was less frequent with steroid avoidance than with steroid withdrawal.

AUTHORS' CONCLUSIONS

This review confirms that steroid avoidance and steroid withdrawal strategies in kidney transplantation are not associated with increased mortality or graft loss despite an increase in acute rejection. These immunosuppression strategies may allow safe steroid avoidance or elimination a few days after kidney transplantation if antibody induction treatment is prescribed or after three to six months if such induction is not used.

Minimization of steroids in kidney transplantation

The goal of steroid minimization trials has been to minimize or eliminate steroid-related side-effects while simultaneously not increasing the rate of acute rejection (AR) and chronic graft loss. Early trials of late steroid withdrawal (> or =3 months post-transplant) were associated with significantly increased AR rates and late graft loss. More recent trials of rapid discontinuation of prednisone (RDP) (< or =7 days post-transplant) have been associated with little or no increase in AR rates and no difference in graft survival (versus maintenance prednisone). Of note, induction therapy appears to be important for success; however, it is not clear if any single maintenance protocol is superior. Intermediate-term follow-up (5-7 years) is now available for some randomized and nonrandomized trials; graft survival and renal function remain excellent. Most of these trials have been done in low immunologic risk recipients, but there are reports of success of RDP in children, black recipients, sensitized recipients, recipients with potentially recurring disease, and kidney-pancreas recipients. Of critical importance, steroid-related side-effects have been minimized. Steroid minimization protocols can clearly be recommended for low-risk patients; additional trials are necessary for those at higher risk. Additional research is also necessary on integrating calcineurin inhibitor minimization with steroid minimization.

Steroid elimination-who, when, how?

Steroids have numerous side effects, many occurring early posttransplantation with relatively low prednisone doses. Consequently, investigators have attempted steroid minimization or withdrawal. The first attempts at steroid minimization used early low-dose steroids and were associated with an increased rate of acute rejection episodes, late graft dysfunction, and graft loss. Subsequent studies, with cyclosporine-based immunosuppression, attempted steroid withdrawal late posttransplantation (>3 months) in highly selected, clinically well, and immunologically low-risk recipients. Again, steroid withdrawal was associated with an increased risk of acute rejection episodes and these episodes were associated with graft dysfunction and increased graft loss. The development of new powerful immunosuppressive agents has led to renewed attempts at late prednisone withdrawal. These also have been associated with increased late rejection risk. A more exciting innovation has been the attempts at rapid discontinuation ( Collapse

Key Words Collapse

MESH Headings

• Adrenal Cortex Hormones/adverse effects
• Antilymphocyte Serum/therapeutic use
• Clinical Trials as Topic
• Drug Administration Schedule
• Drug Therapy, Combination
• Graft Rejection/epidemiology
• Graft Rejection/prevention & control
• Graft Survival/drug effects
• Graft Survival/physiology
• Humans
• Immunosuppressive Agents/therapeutic use
• Kidney Transplantation/immunology
• Prednisone/adverse effects

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Grants

• P01 DK013083 NIDDK NIH HHS
• DK 13083 NIDDK NIH HHS

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Affiliation(s)

A J Matas Department of Surgery, University of Minnesota, Minneapolis, Minnesota 55455, USA.

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Collaborators Collapse

Prevention and management of hyperglycemia after pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation is considered the optimal therapy for patients with insulin-dependent diabetes. Successful pancreas transplantation achieves euglycemia and allows freedom from insulin therapy. Long-term allograft success may be limited by the development of impaired glucose metabolism. The objectives of the present review are to summarize the possible reasons for endocrine pancreatic dysfunction and to focus on its prevention and management and emphasize the role of immunosuppression.

RECENT FINDINGS

The diabetogenic effects of current immunosuppressive agents have been well established. Regimens without corticosteroids and calcineurin-inhibitor minimization or avoidance have been promoted. Recent studies have revisited the pathogenesis of type I and type II diabetes and demonstrated common pathways, including apoptosis induction, for the exhaustion and destruction of the pancreatic islets.

SUMMARY

The immunosuppressive regimens in pancreatic transplantation should be designed and appropriately modified according to the graft immunological and metabolic conditions. New molecules that are able to preserve islet function and maintain optimal insulin secretion should be considered for pancreas transplant recipients.

Minimization and withdrawal of steroids in pancreas and islet transplantation

For reducing the corticosteroid (CS)-related side-effects, especially cardiovascular events, CS-sparing protocols have become increasingly common in pancreas transplantation (PT). Lympho-depleting induction antibodies, such as rabbit anti-thymocyte globulin (rATG) or alemtuzumab, have been widely used in successful trials. The results of various CS-sparing protocols combining calcineurin inhibitors (CNI) and mycophenolate or sirolimus, have been mixed for rejection and survival rates. Most of the studies were uncontrolled trials of low-risk patients, therefore the grade of evidence is limited. Large-scale prospective studies with long-term follow up are necessary to assess risks and benefits of CS-sparing regimens in PT before recommending such strategies as standard practice. Islet allo-transplantation for patients with brittle type 1 diabetes mellitus, less invasive and safer procedure than PT, has been attempted since late 1980s, but diabetogenic immunosuppressants at maintenance, mainly CS and high-dose CNI, prevented satisfactory results (10% insulin-independence at 1-year post-transplant). Since 2000, CS-free and CNI-reducing protocols, including more potent induction [daclizumab, OKT3gamma1(ala-ala) anti-CD3 antibody, rATG] and maintenance (sirolimus, mycophenolate) agents, have significantly improved short-term outcomes whereas long-term are still inadequate (from 80% to 20% insulin-independence from 1- to 5-year post-transplant). Main limitations are allo- and autoimmunity, immunosuppression-related islet and systemic toxicity and transplant site unsuitability, which tolerogenic protocols and biotechnological solutions may solve.

Steroid-free maintenance immunosuppression with rapamune and low-dose neoral in pancreas transplant recipients

BACKGROUND

Steroid-free immunosuppression is an attractive option because it avoids the many side effects of chronic corticosteroid use. It is especially attractive in pancreas recipients because it avoids the diabetogenic effects of steroids.

METHODS

We evaluated the outcome of a steroid-free maintenance immunosuppressive protocol in pancreas transplant recipients. Between August 2003 and May 2006, a total of 97 pancreas transplant recipients received steroid-free maintenance immunosuppression, consisting of induction with thymoglobulin and prednisone for the first 5 days. Patients were maintained on sirolimus adjusted to a target rapamycin trough level and reduced-dose cyclosporine adjusted to target C2 levels. All pancreas transplants (n=124) performed in the previous 3 years and maintained on a steroid-based immunosuppressive protocol with cyclosporine and mycophenolate mofetil were used for comparison.

RESULTS

One-year patient and death censored pancreas graft survival were 93.8% and 94.8% for the steroid free group versus 95.2% and 87.9% for the comparator group, respectively. The incidence of acute rejection was 9.3% in the steroid-free group versus 28.3% in the comparator group (P<0.01). No pancreas loss in the steroid-free group was caused by acute rejection, whereas seven (5.6%) patients in the comparator group lost their pancreases because of acute rejection (P<0.05). At 1 year after transplant, the mean serum glucose and creatinine levels were not different between the two groups.

CONCLUSION

We conclude that excellent graft survival with a significantly lower incidence of acute rejection can be achieved using a steroid-free maintenance immunosuppressive protocol consisting of sirolimus and cyclosporine.

Early steroid withdrawal in solitary pancreas transplantation results in equivalent graft and patient survival compared with maintenance steroid therapy

Although steroid withdrawal in simultaneous kidney pancreas transplantation has been shown to be feasible, the results of early steroid withdrawal in immunologically solitary pancreas transplantation are not well known. This study evaluated an early steroid withdrawal protocol in this group. The results of steroid withdrawal at 21 d post-transplant in solitary pancreas transplant recipients was compared with a control group consisting of solitary pancreas transplant recipients maintained on steroids (MG). Additional immunosuppression consisted of rabbit anti-thymocyte globulin induction followed by tacrolimus and mycophenolate mofetil in both groups. The withdrawal group (WG, n = 22) consisted of 11 pancreas transplant alone (PTA), six pancreas after kidney (PAK), and five simultaneous cadaveric pancreas living kidney (SPLK) recipients. The steroid maintenance group (MG, n = 32) consisted of 8 PTA, 11 PAK, and 13 SPLK recipients. Recipient and donor demographic characteristics were similar. Seventy eight percent of MG patients had infection-related complications in the first year compared with 50% of the WG patients (p = 0.04). The one-yr rejection, pancreas graft, and patient survival rates were 27.3% 95.5%, and 100% in the WG, and 37.5%, 81.3%, and 93.8% in the MG respectively and not significantly different. We conclude that early corticosteroid withdrawal in isolated pancreas transplantation results in fewer infections and can be achieved without an increased risk of rejection or graft loss over the first year.

Long-Term Cell Monitoring of Kidney Recipients After an Antilymphocyte Globulin Induction With and Without Steroids

BACKGROUND

Because of several side effects, the corticosteroid usage has been minimized in kidney transplantation. The increased acute rejection episodes associated with their withdrawal may counterbalance with induction treatment using polyclonal antilymphocyte globulin (ALG). The effects of ALG on blood cell phenotype have already been the subject of several reports. However, to date, no data are available concerning the comparison of blood phenotype when ALG is given with or without steroids and no gene profiling study has been performed.

METHODS

We report here on a longitudinal blood cell analysis of a selected cohort of kidney recipients enrolled in a randomized study of steroid avoidance or withdrawal (during 6 months) during ALG induction.

RESULTS

In the two groups, ALG quickly and massively depleted all the T cells and natural killer cells, but not B cells. Interestingly, the lymphopenia-driven homeostatic proliferation of CD4 and CD8T cells strongly differed with persistent low CD4 (including CD25CD4) T-cell counts. Effector memory CD8T cells reappeared rapidly. ALG induced apoptosis-associated molecules and increased myeloid cell genes. However, few genes were found differentially expressed with a low fold ratio between the two groups during and at distance of corticotherapy.

CONCLUSION

Thus initial steroid avoidance or withdrawal associated with ALG induction has a weak influence on phenotype and transcriptional pattern of blood leukocytes. In contrast, ALG therapy induces an early and strong depletion of all T-cell subsets with contrasted long-lasting homeostatic regulation.

Immunosuppressive standards in simultaneous kidney?pancreas transplantation

Simultaneous pancreas-kidney transplantation is an established procedure for patients with type I diabetes and end-stage renal disease. Continuous advances in the operation techniques with consequent reduction of perioperative morbidity and mortality and the introduction of modern immunosuppressive agents improved not only patients but also graft survival and significantly decreased rejection episodes of both kidney and pancreas grafts. Availability of a variety of new immunosuppressants in the clinical routine and increasing experience of the transplant specialists allowed further developments of therapeutic schemes with application of induction and maintenance immunosuppressive protocols. In this article, we summarize the current status of immunosuppressive regimens in simultaneous pancreas and kidney transplantation.

Simultaneous corticosteroid avoidance and calcineurin inhibitor minimization in renal transplantation

Steroids and calcineurin inhibitors (CNI) have been mainstays of immunosuppression but both have numerous side effects that are associated with substantial morbidity and mortality. This study was carried out to determine if steroids can be eliminated with early discontinuation of cyclosporine A (CsA) and later discontinuation of mycophenolate mofetil (MMF). Ninety-six patients with kidney transplants were entered into four subgroups of two pilot studies. All patients received Thymoglobulin induction, rapamycin (RAPA), and the immunonutrients arginine and an oil containing omega-3 fatty acids. Mycophenolate mofetil was started in standard doses and discontinued by 2 years. CsA was given in reduced doses for either 4, 6, or 12 months. Follow-up was 12-36 months. Thirteen first rejection episodes occurred during the first year (14%). Combining all patients, 86% were rejection-free at 1 year, 80% at 2 years and 79% at 3 years. No kidney has been lost to acute rejection. Ninety percent of the 84 patients at risk at the end of the study were steroid-free and 87% were off CNI. Fifty-seven percent of 54 patients with a functioning kidney at 3 years were receiving monotherapy with RAPA. We conclude that this therapeutic strategy is worthy of a prospective multi-center clinical trial.

Alemtuzumab induction and prednisone-free maintenance immunotherapy in simultaneous pancreas-kidney transplantation comparison with rabbit antithymocyte globulin induction - long-term results

This study compared the effects of using two T-cell depleting antibodies, alemtuzumab (anti-CD 52, Campath-1H) and rabbit antithymocyte globulin (Thymoglobulin), as induction immunosuppression for recipients of simultaneous pancreas-kidney transplantation given a prednisone-free maintenance regimen. We used a single-center, nonrandomised, retrospective, sequential study design to evaluate the efficacy and safety of alemtuzumab (n = 50) or antithymocyte globulin (n = 38) induction in combination with a prednisone-free, tacrolimus/sirolimus-based immunosuppression protocol. Kaplan-Meier analyses of long-term patient and graft survivals and rejection rates were determined according to induction agent. Secondary endpoints included the quality of renal allograft function, incidence of infectious and malignant complications, and cost considerations. Overall long-term patient and graft survival rates did not significantly differ between patients treated with alemtuzumab and antithymocyte globulin. Rejection rates were also nearly equivalent at 1 and 2 years. Viral infectious complications were statistically significantly lower in the alemtuzumab group. The cost of alemtuzumab induction was lower than antithymocyte globulin. Alemtuzumab induction followed by steroid-free maintenance therapy with a tacrolimus/sirolimus-based immunosuppression regimen provided an effective, safe and cost-conscious approach to SPK transplantation.

Steroid-free immunosuppression for pancreas-after-liver transplantation

Simultaneous pancreas-kidney transplantation is presently a well-accepted procedure for patients with type 1 diabetes mellitus and renal failure. However, experiences with combined pancreas and liver transplantation are scarce, a few data are available about the best immunosuppression for these patients. We report our experience with two patients who received a pancreas after liver transplantation for long-standing insulin-dependent diabetes mellitus, with steroid-free immunosuppression based on daclizumab, tacrolimus, and mycophenolate mofetil. Short- and long-term evolution was uneventful. Currently, both patients are insulin free with appropriate metabolic control after 12 and 6 months follow-up. Considering our preliminary results, we suggest a steroid-free immunosuppressive regimen as an option for pancreas-after-liver transplantation.

Steroid-free immunosuppression in organ transplantation

Although steroids have been the cornerstone of immunosuppressive regimens to treat and prevent rejection in organ transplantation, the past decade has seen many successful attempts to minimize or eliminate steroid use. This has been undertaken to decrease the diverse side effects seen with chronic steroid treatment. These efforts have focused on both steroid avoidance and complete elimination, and have been successful across broad patient groups. The key to these efforts has been the adoption of induction protocols with either lymphocyte-depleting agents or anti-interleukin-2 strategies, coupled with the use of the newer maintenance immunosuppressants. In this review, we address the feasibility and benefits of steroid-free and steroid avoidance protocols in kidney, pancreas, liver, and heart transplantation.

Polyclonal Antibody-Induced Serum Sickness in Renal Transplant Recipients: Treatment with Therapeutic Plasma Exchange

Serum sickness is an immune-complex mediated illness that frequently occurs in patients after polyclonal antibody therapy (ATGAM or thymoglobulin). Serum sickness presents with significant morbidity but is self-limited and resolves with prolonged steroid therapy. We present five renal transplant patients who developed serum sickness after polyclonal antibody treatment with severe symptoms that persisted after being started on systemic steroids. These patients underwent one or two courses of therapeutic plasma exchange (TPE) with subsequent complete resolution of their symptoms. Renal transplant recipients with serum sickness after polyclonal antibody therapy may benefit from TPE by accelerating their time to recovery and thereby reducing overall morbidity.

Reduction of CMV disease with steroid-free immunosuppresssion in simultaneous pancreas-kidney transplant recipients

The impact of a prednisone-free immunosuppressive regimen was evaluated in simultaneous pancreas-kidney (SPK) recipients. Patient and graft survivals, rejection rates and the incidence of CMV disease were determined. Two hundred consecutive SPK transplant recipients received tacrolimus-based immunosuppression with (n = 100) or without (n = 100) chronic prednisone therapy. Patients were induced with lymphocyte depleting antibodies or IL-2 receptor blockers and received prophylactic antiviral therapy. Patient and graft survivals and rejection rates were not statistically significantly different between treatment groups. Two-year cumulative incidence of CMV in recipients in the prednisone-free protocol was reduced (7.2% vs. 16%; p = 0.15). Considering only recipients at highest risk (D+/R- or D+R+), incidence of CMV disease in the prednisone-free group (n = 61) compared to the steroid-treated group (n = 48) was reduced from 36% to 18% (p < 0.05). Multivariate analysis confirmed the independent effect of prednisone treatment on the incidence of CMV (RR 2.3; p = 0.04). In the prednisone-free protocol, incidence of CMV was less frequent in recipients receiving induction with Campath versus rabbit antilymphocyte globulin (2.4% vs. 12.6%; p = 0.14). Eliminating prednisone immunotherapy did not adversely affect outcomes and was associated with a reduced rate of CMV in SPK recipients of organs from sero-positive donors.

Steroid avoidance versus steroid withdrawal after simultaneous pancreas-kidney transplantation

Two steroid-sparing immunosuppressive regimens were prospectively compared in recipients of simultaneous pancreas-kidney transplants, one did not include steroids at all and the other included steroids for the first 3 months following transplantation. All patients received rabbit anti-thymocyte globulin, mycophenolate mofetil (MMF) and cyclosporine. Fifty patients were randomised in an open-label, single center and prospective study. The incidence of biopsy-proven acute rejection during the first 12 months after transplantation was the primary endpoint of the study. The incidence of biopsy-proven acute rejection was 4% in both groups. No statistically significant difference in patient (96 and 100%), kidney (96 and 100%) or pancreas (84 and 92%) survival was observed 1 year after transplantation in the steroid avoidance and steroid withdrawal groups, respectively. The total number of adverse events (including severe ones), length of hospitalization and infectious episodes did not differ between groups. Blood glucose and insulin levels, lipid profile and hemoglobin A1C levels did not differ statistically between the two groups. However, the 1-year serum creatinine level was significantly higher in the steroid avoidance group (132 vs. 114 micromol/L; p = 0.02). Steroid avoidance and steroid withdrawal 3 months after transplantation are safe and effective regimens for diabetic patients with pancreas-kidney transplants.

Management of hyperglycaemia after pancreas transplantation: are new immunosuppressants the answer?

Pancreas transplantation is considered the optimal therapy for patients with diabetes mellitus who reach end-stage renal disease. Despite achievement of euglycaemia after this procedure, the progression to impaired pancreatic function and metabolic exhaustion still represents one of the major concerns that increase the risk of graft loss. This paper reviews the possible mechanisms that can induce post-transplant hyperglycaemia, including those related to immunosuppression and those non-related, and the new strategies available for minimising or preventing this complication. Different aetiologies can induce pancreatic dysfunction. Technical complications, acute pancreatitis and delayed graft function, mostly related to impaired insulin secretion, are considered the early causes for abnormal glucose control. In general, acute rejection does not affect the endocrine portion of the pancreas graft because islet destruction occurs later than the inflammation of the exocrine components. Hyperinsulinaemia and insulin resistance represent the main concern for the progression of blood glucose intolerance. The anastomotic techniques of the exocrine portion of the pancreas and the immunosuppressive regimens are of critical importance for the development of impaired glucose metabolism. Hyperinsulinaemia, as a result of the fact that systemic-enteric or systemic-bladder drainages reducing the hepatic clearance of insulin, has led to the introduction of more physiological techniques using portal drainage of the endocrine secretions. Experimental and clinical data have shown that many of the current immunosuppressants account, to a large degree, for the increased risk of the development of post-transplant hyperglycaemia. The most common maintenance regimen in pancreatic transplantation still consists of triple therapy with a combination of corticosteroids, calcineurin inhibitors (either ciclosporin [cyclosporine] or tacrolimus), and mycophenolate mofetil (MMF).The diabetogenic effects of corticosteroids and calcineurin inhibitors have resulted in the need for protocols able to minimise their use. Recent studies have shown the safety and efficacy of steroid-sparing or -free regimens. Sirolimus has shown powerful immunosuppressive potency in absence of nephrotoxicity and diabetogenicity. Multicentre and single-centre reports have demonstrated that both calcineurin inhibitor withdrawal and avoidance were possible when sirolimus was used in a concentration-controlled fashion, with low-dose corticosteroids and MMF. Although the experience with sirolimus in pancreatic transplantation is still limited, the results are promising. Patients affected by diabetic gastroparesis seem to better tolerate a regimen with sirolimus and low-dose tacrolimus than one with tacrolimus in combination with MMF.For successful, long-term results of pancreatic transplantation, it is crucial to combine donor selection, technical aspects, modified anastomotic techniques and new therapeutic approaches designed to minimise the metabolic and non-metabolic adverse effects of the immunosuppressive regimens.

Evolving surgical strategies for pancreas transplantation

Pancreas transplant has become a reliably predictable treatment and cure for patients with type 1 diabetes mellitus and hypoglycemic unawareness or renal failure. During the past 2 years, the use of enteric drainage has been shown to decrease morbidity over traditional bladder drainage, and the use of the portal system for venous drainage continues to be explored. Technically, the use of circular staplers, over a hand-sown anastomosis for duodenal drainage, has gained popularity, and alternative arterial reconstruction methods have been developed. Living donor pancreas and kidney transplants are also becoming more common throughout the world. In the area of immunosuppression, steroid-free protocols, now commonplace in kidney transplants, are being applied successfully to pancreas transplantation. Finally, the benefit of solitary pancreas and pancreas after kidney transplantation has been questioned, and a more complete analysis of pancreas alone and pancreas after kidney transplants is anticipated in the near future.

Successful simultaneous islet-kidney transplantation using a steroid-free immunosuppression: two-year follow-up

We report on the feasibility of a glucocorticoid-free immunosuppression (sirolimus, low-dose tacrolimus, and daclizumab) in simultaneous islet-kidney transplantation in nine patients with type 1 diabetes. There was one renal primary nonfunction. Renal function (n = 8) as assessed by creatinine and creatinine clearance over time was 103 +/- 6 micromol/L and 64 +/- 6 mL/min/1.73 m(2), respectively. Five out of six patients with >or= 2 islet transplantations became insulin independent. The mean HbA(1c) during the follow-up period for all patients after transplantation is 6.2 +/- 0.9% as compared with 8.7 +/- 1.9% prior to transplant. These results in patients with a median follow-up of 2.3 years suggest that kidney transplantation under a glucocorticoid-free immunosuppression is feasible, and that the rate of insulin independence of 80% can be achieved not only in patients with no or minimal diabetes complications, but also in patients with more advanced late complications and in conjunction with kidney transplantation.

Outcome at 3 years with a prednisone-free maintenance regimen: a single-center experience with 349 kidney transplant recipients

Historically, late steroid withdrawal after kidney transplants has been associated with an increased rejection rate. Recently, low rejection rates have been reported for recipients treated with complete avoidance or rapid elimination of steroids. However, follow-up has been short. We herein report on 3-year outcome in recipients whose prednisone was rapidly eliminated and who were maintained on a steroid-free regimen. From 10/1/1999 through 5/1/2003, 349 recipients (254 LD, 95 CAD; 319 in first 30 s) were immunosuppressed with polyclonal antibody (Thymoglobulin), a calcineurin inhibitor, either mycophenolate mofetil or sirolimus, and rapid discontinuation of prednisone. Actuarial 3-year patient survival was 95%; graft survival, 93%. Acute rejection-free graft survival at 1 year was 94%; at 3 years, 92%. There was no difference between LD and CAD. At 2 years, the mean (+/- SE) serum creatinine level for LDs was 1.6 +/- 0.5 mg/dL; for CAD, 1.6 +/- 0.4 mg/dL. We have no new cases of PTLD or avascular necrosis; 22 recipients (6%) developed CMV. Currently, 84% of recipients remain prednisone-free. We conclude that excellent 3-year patient and graft survival can be achieved without maintenance prednisone. With such a protocol, steroid-related side-effects are minimal.

Metabolic effects of a corticosteroid-free immunosuppressive regimen in recipients of pancreatic transplant

BACKGROUND

A corticosteroid (CS)-free immunosuppressive regimen may be considered less diabetogenic than treatments including CSs principally after pancreas transplantation.

METHODS

To test whether a CS-free immunosuppressive treatment is metabolically superior to a regimen including CSs, we prospectively studied 19 CS-free simultaneous pancreas and kidney (SPK) transplant recipients (body mass index=22+/-1 kg/m2; cyclosporine dose=400+/-19 mg/kg/day; azathioprine dose=77+/-8 mg/day; basal plasma C-peptide=1.3+/-0.12 ng/mL) and 12 matched CS-treated SPK transplant recipients (prednisone dose=9+/-1 mg/day; basal C-peptide=2.2+/-0.2 ng/mL) by means of the 6,6-2H(2)-glucose infusion and the euglycemic insulin clamp (1 mU/kg/min, insulin infusion rate). In addition, six renal transplant recipients receiving a CS-free regimen were also studied as a control group.

RESULTS

In the postabsorptive state, CS-treated SPK transplant recipients demonstrated comparable plasma glucose levels but higher plasma insulin levels than CS-free SPK transplant recipients. Plasma triglyceride levels were significantly higher in CS-treated SPK patients than in CS-free SPK patients (1.16+/-0.16 mg/dL vs. 0.88+/-0.08; P<0.05). High-density lipoprotein and apoprotein A(1) levels were similar in both groups. No difference was observed in pyruvate, lactate, beta-OH-butyrate, and basal endogenous glucose production in all three groups of patients studied. During euglycemic hyperinsulinemia, the inhibition of endogenous glucose production and the stimulation of tissue glucose disposal were not statistically different among the three groups.

CONCLUSIONS

SPK recipients receiving chronic low-dose CS maintenance therapy do not present a lower glucose disposal than CS-free recipients. Nonetheless, this is obtained at the expense of a higher endogenous insulin secretion, which can cause an alteration of the triglyceride profile.

Dialysis, kidney transplantation, or pancreas transplantation for patients with diabetes mellitus and renal failure: a decision analysis of treatment options

Patients with type 1 diabetes mellitus and end-stage renal disease may remain on dialysis or undergo cadaveric kidney transplantation, living kidney transplantation, sequential pancreas after living kidney transplantation, or simultaneous pancreas-kidney transplantation. It is unclear which of these options is most effective. The objective of this study was to determine the optimal treatment strategy for type 1 diabetic patients with renal failure using a decision analytic Markov model. Input data were obtained from the published medical literature, the United Network for Organ Sharing registry, and patient interviews. The outcome measures were life expectancy (in life-years [LY]) and quality-adjusted life expectancy (in quality-adjusted life-years [QALY]). Living kidney transplantation was associated with 18.30 LY and 10.29 QALY; pancreas after kidney transplantation, 17.21 LY and 10.00 QALY; simultaneous pancreas-kidney transplantation, 15.74 LY and 9.09 QALY; cadaveric kidney transplantation, 11.44 LY and 6.53 QALY; dialysis, 7.82 LY and 4.52 QALY. The results were sensitive to the value of several key variables. Simultaneous pancreas-kidney transplantation had the greatest life expectancy and quality-adjusted life expectancy when living kidney transplantation was excluded from the analysis. These data indicate that living kidney transplantation is associated with the greatest life expectancy and quality-adjusted life expectancy for type 1 diabetic patients with renal failure. Treatment strategies involving pancreas transplantation should be considered for patients with frequent metabolic complications of diabetes and for those patients who favor kidney-pancreas transplantation over kidney transplantation alone. For patients without a living donor, simultaneous pancreas-kidney transplantation is associated with the greatest life expectancy.

A prospective study of rapid corticosteroid elimination in simultaneous pancreas-kidney transplantation: comparison of two maintenance immunosuppression protocols: tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus

BACKGROUND

We examined the feasibility of rapid corticosteroid elimination in simultaneous pancreas kidney transplantation.

METHODS

Forty consecutive simultaneous pancreas-kidney (SPK) transplant recipients were enrolled in a prospective study in which antithymocyte globulin induction and 6 days of corticosteroids were administered along with tacrolimus and MMF (n=20) or tacrolimus and sirolimus (n=20). Mean+/-SD follow-up for recipients receiving tacrolimus/MMF and tacrolimus/sirolimus were 12.7+/-3.9 and 13.4+/-2.9 months, respectively. Patient and graft survival, and rejection rates were compared to an historical control group (n=86; mean follow-up 41.5+/-15.4 months) of SPK recipients that received induction and tacrolimus, MMF, and corticosteroids.

RESULTS

Demographic characteristics of recipient and donor variables were similar among all groups. The 1-year actuarial patient, kidney, and pancreas survival rates in the 40 SPK transplant recipients with rapid corticosteroid elimination were 100, 100, and 100%, respectively. In the historical control group the 1-year actual patient, kidney, and pancreas survival rates were 96.5, 93.0, and 91.9%, respectively. The 1-year rejection-free survival rate recipients in the rapid steroid elimination group collectively was 97.5 vs 80.2% in the historical control group (P=0.034). At 6 and 12 months posttransplant the serum creatinine values remained stable in all groups.

CONCLUSIONS

We conclude that chronic corticosteroid exposure is not required in SPK transplant recipients receiving antithymocyte globulin induction and maintenance immuno-suppression consisting of either tacrolimus and mycophenolate mofetil or tacrolimus and sirolimus.

6-Methylprednisolone does not impair anti-thymocyte globulin (ATG) immunosuppressive activity in non-human primates

BACKGROUND

Induction treatments with anti-thymocyte globulin (ATG) in solid organ transplantation may enhance the efficacy of maintenance immunosuppressive therapy. Since ATG can trigger Fas (CD95) mediated T cell apoptosis, a process antagonized in vitro by corticosteroids, an important issue is whether corticosteroids could interfere with T cell depleting and immunosuppressive activities of ATG.

METHODS

MHC mismatched skin allografts were performed on cynomolgus and rhesus monkeys treated with ATG (20 mg/kg) associated or not with 6-methylprednisolone (10 mg/kg).

RESULTS

There was no difference between the two immunosuppressive regimens as regards the intensity and duration of peripheral T lymphocyte depletion and the appearance of anti-ATG antibodies. Skin graft survival was increased in monkeys treated with 6-methylprednisolone as compared with ATG alone.

CONCLUSIONS

In vivo, corticosteroids do not interfere with ATG ability to induce massive T cell depletion and to delay skin allograft rejection in non-human primates.

Rapid discontinuation of steroids in living donor kidney transplantation: a pilot study

Steroids are associated with significant postoperative complications (hypertension, cosmetic changes, bone loss, hyperlipidemia, diabetes, and cataracts). Most develop early; in addition, late post-transplant steroid withdrawal in kidney transplant recipients has been associated with increased acute rejection (AR). To obviate these problems, we studied outcome of a protocol of rapid discontinuation of prednisone (RDS) (steroids stopped on POD6). Between November 1, 1999 and October 31, 2000, 51 adult living donor (LD) first transplant recipients (2 HLA-id, 28 non-id relative, 21 LURD) were immunosuppressed with thymoglobulin (1.25 mg/kg intraoperatively and then qdx4); prednisone (P) (500 mg methylprednisolone intraoperatively, 1 mg/kg x 1 day, 0.5 mg/kg x 2 days, 0.25 mg/kg x 2 days, then d/c); MMF, 1 g b.i.d.; and CSA, 4 mg/kg b.i.d. adjusted to achieve levels of 150-200 ng/mL (by HPLC). Exclusion criteria were delayed graft function or primary disease requiring P. Minimum follow-up was 5.5 months (range 5.5 to 17.5 months). Outcome was compared vs. previous cohorts of LD recipients immunosuppressed with P/AZA/CSA (n = 171) or P/MMF/CSA (n = 43) (both without antibody induction).

RESULTS

For the RDS group, average CSA level (+/- S.E.) at 3 and 6 months was 190 +/- 12 and 180 +/- 9; avg. MMF dose, 1.7 +/- 0.1 g and 1.7 +/- 0.1 g. There was no significant difference in 6- and 12-month actuarial patient survival, graft survival and rejection-free graft survival between recipients on the RDS protocol vs. historical controls. For RDS recipients, actuarial 6- and 12-month rejection-free graft survival was 87%. Of the 51 RDS recipients, five (10%) have had AR (at 20 days, 1 month, 3 months, 3 months, and 3.5 months post-transplant). After treatment, all five were maintained on 5 mg P; there have been no second AR episodes. Two additional recipients were started on 5 mg P due to low white blood count (WBC) and low/no MMF. Of the 51 grafts, one has failed (death with function). Average serum Cr level (+/- S.E.) at 3 and 6 months for RDS recipients was 1.7 +/- 0.5 (NS vs. historical controls).

CONCLUSION

For low-risk LD recipients, a kidney transplant with an RDS protocol does not increase risk of AR or graft loss. Future studies will need to be done to assess AR rates with an RDS protocol in cadaver transplant recipients and in recipients with delayed graft function.

Trends and perspectives in pancreas and simultaneous pancreas and kidney transplantation

Pancreas transplantation is still the best option to achieve normoglycaemia and insulin independence in patients with type I diabetes. As a result of improvements in surgical techniques, immunosuppression and patient selection, one year survival rates of 95, 83, and 88% for patient, pancreas, and kidney survival, respectively, are reported for patients with simultaneous pancreas and kidney transplantation. The main goals for the future are to reduce postoperative morbidity, to identify the relevant indications for single pancreas transplantation, to adopt the best surgical technique for individual patients' needs (bladder versus enteric drainage with or without portal venous delivery of insulin), and to develop immunosuppressive strategies with low nephrotoxic and diabetogenic potential.

Prevention of acute rejection with antithymocyte globulin, avoiding corticosteroids, and delaying cyclosporin after renal transplantation

BACKGROUND

Despite their well-known side-effects, corticosteroids (Cs) are currently used after kidney transplantation. Avoidance of Cs may improve patient quality of life and eventual long-term survival. We report on a regimen using antithymocyte globulin (ATG) and mycophenolate mofetil (MMF) for induction, and cyclosporin (CsA) plus MMF for maintenance treatment of recipients of primary kidney transplantation.

METHODS

We studied 11 consecutive, non-sensitized renal transplant patients (nine cadaver and two living donors). Initial immunosuppression consisted of ATG (1.5 mg/kg/day, i.v.) given for 10 days and MMF (1.0 g/b.i.d.). CsA (8 mg/kg, in two divided doses) was started on post-operative day 11. Cs were only allowed in the case of MMF discontinuation, for the treatment of acute rejection, and in the event of recurrence of the primary glomerulonephritis.

RESULTS

All patients completed the entire 10-day ATG course. Main side-effects included fever (>38 degrees C) and serum sickness, observed in 73 and 27% of the patients respectively. The incidence of acute rejection was 27% (three of 11 patients). In two patients with acute rejection, serum sickness was concomitantly diagnosed and renal histology was partially compatible with immune-complex disease. The remaining patient had two episodes of low-grade rejection. All rejection episodes were rapidly reversed. Two patients (18%) were treated with ganciclovir for cytomegalovirus (CMV) infection. Two patients (18%) are currently receiving Cs for recurrence of the native glomerulonephritis and two rejection episodes respectively. All patients are currently alive with functioning kidneys (average follow-up of 8.4 months; average creatinine level of 128 micromol/l).

CONCLUSION

This pilot study suggests that ATG induction in combination with MMF and delayed introduction of CsA, in the absence of Cs, is not well tolerated in recipients of kidney transplants. An earlier introduction of calcineurin inhibitors and/or a shorter course of ATG may reduce the incidence of fever and serum sickness secondary to ATG.