Alemtuzumab induction and tacrolimus monotherapy in pancreas transplantation: One- and two-year outcomes

Pancreas after kidney transplantation, is it the time to overcome the stigma?

BACKGROUND

Pancreas transplantation is the most effective treatment to improve quality of life and overcome complications in patients with end-stage renal disease and diabetes mellitus. One of the main approaches for concurrent renal disease and diabetes mellitus which has been underutilized during the past decade is a pancreas transplant after kidney transplantation. Our study aimed to quantify outcomes following pancreas after kidney transplants (PAKs) in the United States from 2001 to 2020 with an emphasis on graft and patient survival.

METHODS AND MATERIALS

A retrospective registry analysis was performed by accessing the OPTN/UNOS database for PAKs that were performed in the United States from January 2001 to April 2020. The study population was divided into two subgroups: patients receiving a pancreas transplant between 2001 and 2010 and those receiving a pancreas transplant between 2011 and 2020.

RESULTS

The study examined a total number of 3706 PAK recipients; patients who received a PAK from January 2001 through December 2010 (n = 2892) and those who received a PAK from January 2011 to April 2020 (n = 814). The selection process of transplant recipients did not drastically change throughout the 2001-2010 and 2011-2020 periods. Length of stay at the hospital after the transplantation improved significantly in the 2011-2020 group relative to the 2001-2010 group (8.48 vs. 10.08 days, mean, p < 0.01). Additionally, more transplantation with 4-6 human leukocyte antigen mismatch occurred in the 2011-2020 group than in the 2001-2010 group (80.6% vs. 71.4%, p < 0.01). The pancreas preservation time of 13.35 h in the 2001-2010 group decreased significantly to 11.17 h in the 2011-2020 group (p < 0.001). The mean donor's amylase and lipase also decreased significantly in the 2011-2020 cohort. Significant graft survival improvement was observed in the 2011-2020 group compared to the 2001-2010 group after a long-term follow-up (p < 0.001). The mean Calculated Pancreas Donor Risk Index was 1.08 for the 2001-2010 group and 0.99 for the 2011-2020 group with a significant difference (p < 0.001).

CONCLUSION

The beneficial results and improved outcomes observed in PAK patients demonstrate the effectiveness of the operation for individuals in need of a pancreas transplant. PAKs can prove to be a meaningful solution to overcome long waiting times, decrease the donor-recipient imbalance, expand the donor pool, and overcome the current underutilization in order to improve the short- and long-term quality of life in the groups of interest.

First World Consensus Conference on pancreas transplantation: Part II - recommendations

The First World Consensus Conference on Pancreas Transplantation provided 49 jury deliberations regarding the impact of pancreas transplantation on the treatment of diabetic patients, and 110 experts' recommendations for the practice of pancreas transplantation. The main message from this consensus conference is that both simultaneous pancreas-kidney transplantation (SPK) and pancreas transplantation alone can improve long-term patient survival, and all types of pancreas transplantation dramatically improve the quality of life of recipients. Pancreas transplantation may also improve the course of chronic complications of diabetes, depending on their severity. Therefore, the advantages of pancreas transplantation appear to clearly surpass potential disadvantages. Pancreas after kidney transplantation increases the risk of mortality only in the early period after transplantation, but is associated with improved life expectancy thereafter. Additionally, preemptive SPK, when compared to SPK performed in patients undergoing dialysis, appears to be associated with improved outcomes. Time on dialysis has negative prognostic implications in SPK recipients. Increased long-term survival, improvement in the course of diabetic complications, and amelioration of quality of life justify preferential allocation of kidney grafts to SPK recipients. Audience discussions and live voting are available online at the following URL address: http://mediaeventi.unipi.it/category/1st-world-consensus-conference-of-pancreas-transplantation/246.

The survival advantage of pancreas after kidney transplant

Patient survival after pancreas after kidney transplant (PAK) has been reported to be inferior to patient survival after simultaneous pancreas-kidney transplant (SPK). The authors examine national data to further explore allograft (kidney and pancreas) and patient survival after PAK. Kaplan-Meier and Cox proportional hazard models were used to analyze Organ Procurement and Transplantation Network data from 1995 to 2010. The analysis compared PAK and SPK candidates and recipients. Kaplan-Meier analysis results showed that PAK after either a living or a deceased donor kidney transplant is associated with increased kidney graft survival compared with recipients with type 1 diabetes who received only a kidney. The best kidney allograft survival was for patients who received a living donor kidney followed by PAK. Receiving a living donor kidney was associated with increased pancreas allograft survival compared with receiving a deceased donor kidney. PAK transplant recipients who receive both organs have a survival advantage compared with uremic candidates who receive neither (SPK waitlist). Compared with uremic diabetic waitlist patients, SPK and PAK recipients showed similar overall patient survival. Successful PAK offers a survival advantage compared with receiving neither a kidney nor a pancreas transplant. These data also suggest that receiving a pancreas (after kidney) transplant may have a protective effect on the kidney allograft.

Pancreas transplantation: The Wake Forest experience in the new millennium

AIM: To investigate the Wake Forest experience with pancreas transplantation in the new millennium with attention to surgical techniques and immunosuppression.

METHODS: A monocentric, retrospective review of outcomes in simultaneous kidney-pancreas transplant (SKPT) and solitary pancreas transplant (SPT) recipients was performed. All patients underwent pancreas transplantation as intent-to-treat with portal venous and enteric exocrine drainage and received depleting antibody induction; maintenance therapy included tapered steroids or early steroid elimination with mycophenolate and tacrolimus. Recipient selection was based on clinical judgment whether or not the patient exhibited measureable levels of C-peptide.

RESULTS: Over an 11.25 year period, 202 pancreas transplants were performed in 192 patients including 162 SKPTs and 40 SPTs. A total of 186 (92%) were primary and 16 (8%) pancreas retransplants; portal-enteric drainage was performed in 179 cases. A total of 39 pancreas transplants were performed in African American (AA) patients; of the 162 SKPTs, 30 were performed in patients with pretransplant C-peptide levels > 2.0 ng/mL. In addition, from 2005-2008, 46 SKPT patients were enrolled in a prospective study of single dose alemtuzumab vs 3-5 doses of rabbit anti-thymocyte globulin induction therapy. With a mean follow-up of 5.7 in SKPT vs 7.7 years in SPT recipients, overall patient (86% SKPT vs 87% SPT) and kidney (74% SKPT vs 80% SPT) graft survival rates as well as insulin-free rates (both 65%) were similar (P = NS). Although mortality rates were nearly identical in SKPT compared to SPT recipients, patterns and timing of death were different as no early mortality occurred in SPT recipients whereas the rates of mortality following SKPT were 4%, 9% and 12%, at 1-, 3- and 5-years follow-up, respectively (P < 0.05). The primary cause of graft loss in SKPT recipients was death with a functioning graft whereas the major cause of graft loss following SPT was acute and chronic rejection. The overall incidence of acute rejection was 29% in SKPT and 27.5% in SPT recipients (P = NS). Lower rates of acute rejection and major infection were evidenced in SKPT patients receiving alemtuzumab induction therapy. Comparable kidney and pancreas graft survival rates were observed in AA and non-AA recipients despite a higher prevalence of a “type 2 diabetes” phenotype in AA. Results comparable to those achieved in insulinopenic diabetics were found in the transplantation of type 2 diabetics with detectable C-peptide levels.

CONCLUSION: In the new millennium, acceptable medium-term outcomes can be achieved in SKPT and SPTs as nearly 2/3rds of patients are insulin independent following pancreas transplantation.

Immunosuppression for pancreas transplantation with an emphasis on antibody induction strategies: review and perspective

A review of recent literature was performed to identify trends and evaluate outcomes with respect to immunosuppression in pancreas transplantation (PTX). In the past decade, the majority of PTXs were performed with depleting antibody induction, particularly in the setting of either calcineurin inhibitor minimization, corticosteroid withdrawal or both. Maintenance immunosuppression consisted of predominantly tacrolimus (TAC)/mycophenolatemofetil, TAC/mycophenolic acid or TAC/sirolimus with or without corticosteroids. Depending on PTX category, donor and recipient risk factors, case mix and immunosuppressive regimen, the 1-year incidence of acute rejection has decreased to 5-20%. Current 1-year rates of immunological pancreas graft loss range between 1.8 and 6%. Depleting antibody induction and either TAC/mycophenolatemofetil or TAC/sirolimus maintenance therapy with early steroid withdrawal have become the mainstay of immunosuppression in PTX. However, the development of non-nephrotoxic, nondiabetogenic, and nongastrointestinal toxic regimens is highly desirable to improve quality of life in all solid organ transplant recipients.

Characterization, prophylaxis, and treatment of infectious complications in craniomaxillofacial and upper extremity allotransplantation: a multicenter perspective

BACKGROUND

Vascularized composite allotransplants consist of heterogeneous tissues from different germ layers, which include skin, muscle, bone, fat, nerves, and lymph nodes. The antigenic diversity of these tissues, particularly of the highly immunogenic skin component, necessitates potent immunosuppressive regimens similar to that of some solid organ transplants. Indeed, the lifelong, high-dose, multidrug immunosuppressive protocols expose vascularized composite allotransplant recipients to considerable risk of infectious, metabolic, and neoplastic sequelae. In this article, the authors review the infectious risk to patients after vascularized composite allotransplantation, with special attention to the somewhat limited experience with the prophylaxis and treatment of infections after this innovative reconstructive surgery.

METHODS

A review of the literature was undertaken to elucidate the characterization, prophylaxis, and treatment of all documented infectious complications.

RESULTS

Infections in face and hand vascularized composite allotransplants follow a course similar to that of solid organ transplants. Several differences exist, including the unique flora of craniomaxillofacial transplants, the increased risk of donor-derived infections, and the alteration of the risk-to-benefit ratio for cytomegalovirus infections.

CONCLUSIONS

The patient with a face or limb transplant has many of the same infectious risks as a lung transplant recipient, which include bacterial, viral, and fungal infections. Because of the anatomy, mucosal exposure, and differing donor flora, however, the face or limb transplant is susceptible to invasive diseases from a variety of microbes.

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.

Single dose of alemtuzumab induction with steroid-free maintenance immunosuppression in pancreas transplantation

BACKGROUND

The use of alemtuzumab (humanized anti-CD52 monoclonal antibody) has been primarily studied in renal transplantation, and the experience of alemtuzumab induction in pancreas transplantation is still limited. The objective of this study is to analyze the outcome of pancreas transplantation by using a single dose of 30 mg alemtuzumab induction with steroid-free maintenance immunosuppression.

METHODS

We performed a total 28 pancreas transplants (17 simultaneous kidney-pancreas transplantation [SPK], 5 pancreas after kidney transplantation [PAK], and 6 pancreas transplant alone [PTA]) between November 2006 and April 2010. Median follow-up was 25 months (range, 8-49 months). Maintenance immunosuppression consists of tacrolimus and mycophenolate. We analyzed patient/graft survival, graft function, and complications.

RESULTS

One-year actuarial patient/graft survival was 100%/100% in SPK, PAK, and PTA. Three-year actuarial patient/pancreas graft survival rates for SPK, PAK, and PTA were 100%/100%, 100%/100%, and 100%/83%, respectively. Excellent pancreas and kidney graft functions were observed. Acute cellular rejection occurred in 42% of patients. Most of the rejection episode occurred approximately 1 or 6 months after transplant. Absolute lymphocyte count remained below preoperative level for 1 year posttransplant and WBC counts were significantly lower for 3 years after transplant compared with pretransplant level. Cytomegalovirus infection and bacterial infection occurred in 28% and 36% of patients, respectively. Eleven percent of patients developed donor-specific antibodies and 7% of patients experienced antibody-mediated rejection.

CONCLUSION

A single dose of 30 mg alemtuzumab induction with steroid-free maintenance immunosuppression achieved excellent mid-term patient and graft survival for pancreas transplantation with acceptable complication rate.

Some observations on prope tolerance

PURPOSE OF REVIEW

To outline the rationale of powerful depleting induction therapy with alemtuzumab and minimal maintenance immunosuppression after organ transplantation.

RECENT FINDINGS

The original observations in principle have been confirmed by many independent centres.

SUMMARY

Follow-up of the 'prope tolerance' protocol has confirmed a low incidence of rejection, infection and post transplant lymphoproliferative disorder (PTLD). Especially, encouraging results were obtained in African-Americans. There were few side effects and the regimen was well tolerated by patients. Treg cells were observed in the circulation, which could be an important factor in the mechanisms of graft acceptance using a prope tolerance regimen. There was a considerable reduction in the costs of the transplantation procedure. It is suggested that this minimalisation of maintenance immunosuppression is the best therapy currently available that we can offer to our patients.

Current status of pancreas transplantation

Pancreas transplantation has emerged as the treatment of choice for patients with end-stage diabetes mellitus. Over the last four decades, many improvements have been made in the surgical techniques and immunosuppressive regimens, which contributed to increased number of indications and improved allograft survival. Pancreas transplantation can be justified on the basis that patients replace daily injections of insulin with an improved quality of life but at the expense of a major surgical procedure with a relatively higher complication rate, and lifelong immunosuppression. Therefore, efforts to develop more minimally invasive techniques for endocrine replacement therapy such as islet transplantation have been in progress. This article summarizes the current understanding of pancreas transplantation-associated indications, donor selection, surgical techniques, immunosuppression, and rejection.

Pancreas transplantation: lessons learned from a decade of experience at Wake Forest Baptist Medical Center

This article reviews the outcome of pancreas transplantations in diabetic recipients according to risk factors, surgical techniques, and immunosuppression management that evolved over the course of a decade at Wake Forest Baptist Medical Center. A randomized trial of alemtuzumab versus rabbit anti-thymocyte globulin (rATG) induction in simultaneous kidney-pancreas transplantation (SKPT) at our institution demonstrated lower rates of acute rejection and infection in the alemtuzumab group. Consequently, alemtuzumab induction has been used exclusively in all pancreas transplantations since February 2009. Early steroid elimination has been feasible in the majority of patients. Extensive experience with surveillance pancreas biopsies in solitary pancreas transplantation (SPT) is described. Surveillance pancreas biopsy-directed immunosuppression has contributed to equivalent long-term pancreas graft survival rates in SKPT and SPT recipients at our center, in contrast to recent registry reports of persistently higher rates of immunologic pancreas graft loss in SPT. Furthermore, the impact of donor and recipient selection on outcomes is explored. Excellent results have been achieved with older (extended) donors and recipients, in recipients of organs from donation after cardiac death donors managed with extracorporeal support, and in African-American patients. Type 2 diabetics with detectable C-peptide levels have been transplanted successfully with outcomes comparable to those of insulinopenic diabetics. Our experiences are discussed in the light of findings reported in the literature.

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.

Alemtuzumab induction prior to cardiac transplantation with lower intensity maintenance immunosuppression: one-year outcomes

Induction therapy with alemtuzumab (C-1H) prior to cardiac transplantation (CTX) may allow for lower intensity maintenance immunosuppression. This is a retrospective study of patients who underwent CTX at a single institution from January 2001 until April 2009 and received no induction versus induction with C-1H on a background of tacrolimus and mycophenolate. Those with C-1H received dose-reduced calcineurin inhibitor and no steroids. A total of 220 patients were included, 110 received C-1H and 110 received no induction. Recipient baseline characteristics, donor age and gender were not different between the two groups. Mean tacrolimus levels (ng/mL) for C-1H versus no induction: months 1-3 (8.5 vs. 12.9), month 4-6 (10.2 vs. 13.0), month 7-9 (10.2 vs. 11.9) and month 10-12 (9.9 vs. 11.3) were all significantly lower for the C-1H group, p < 0.001. There were no differences between the C-1H and no induction groups at 12 months for overall survival 85.1% versus 93.6% p = 0.09, but freedom from significant rejection was significantly higher for the C-1H group, 84.5% versus 51.6%, p < 0.0001. In conclusion, induction therapy after CTX with C-1H results in a similar 12 month survival, but a greater freedom from rejection despite lower calcineurin levels and without the use of steroids.

Neutrophils express CD52 and exhibit complement-mediated lysis in the presence of alemtuzumab

Neutropenia is a recognized adverse event in patients treated with the humanized anti-CD52 monoclonal antibody alemtuzumab. However, as it is widely believed that neutrophils do not express CD52, the etiology of alemtuzumab-associated neutropenia is unclear. We have found that neutrophils express both mRNA coding for CD52 and the protein itself on the cell surface. We confirmed cell-surface expression using 3 different anti-CD52 antibodies, and note that neutrophils express lower levels of CD52 than lymphocytes and eosinophils. Further, incubation of alemtuzumab with neutrophils results in dose-dependent, complement-mediated lysis in the presence of both heterologous and autologous complement. These data offer an explanation for the etiology of alemtuzumab-associated neutropenia. In a climate of increased use of alemtuzumab in leukemia and other disease states, as well as in transplantation, these data highlight the need for increased vigilance of emerging neutropenia in patients treated with alemtuzumab.

Pancreas transplantation

Since the introduction of pancreas transplantation more than 40 years ago, efforts to develop more minimally invasive techniques for endocrine replacement therapy have been in progress, yet this surgical procedure still remains the treatment of choice for diabetic patients with end-stage renal failure. Many improvements have been made in the surgical techniques and immunosuppressive regimens, both of which have contributed to an increasing number of indications for pancreas transplantation. This operation can be justified on the basis that patients replace daily injections of insulin with an improved quality of life but at the expense of a major surgical procedure and lifelong immunosuppression. The various indications, categories, and outcomes of patients having a pancreas transplant are discussed, particularly with reference to the effect on long-term diabetic complications.

Immediate retransplantation for pancreas allograft thrombosis

Early pancreas allograft failure most commonly results from thrombosis and requires immediate allograft pancreatectomy. Optimal timing for retransplantation remains undefined. Immediate retransplantation facilitates reuse of the same anatomic site before extensive adhesions have formed. Some studies suggest that early retransplantation is associated with a higher incidence of graft loss. This study is a retrospective review of immediate pancreas retransplants performed at a single center. All cases of pancreas allograft loss within 2 weeks were examined. Of 228 pancreas transplants, 12 grafts were lost within 2 weeks of surgery. Eleven of these underwent allograft pancreatectomy for thrombosis. One suffered anoxic brain injury and was not a retransplantation candidate, one was retransplanted at 3.5 months and nine patients underwent retransplantation 1-16 days following the original transplant. Of the nine early retransplants, one pancreas was lost to heparin-induced thrombocytopenia, one recipient died with function at 2.9 years and the other grafts continue to function at 76-1137 days (mean 572 days). One-year graft survival for early retransplantation was 89% compared to 91% for all pancreas transplants at our center. Immediate retransplantation following pancreatic graft thrombosis restores durable allograft function with outcomes comparable to first-time pancreas transplantation.

Two hundred living donor kidney transplantations under alemtuzumab induction and tacrolimus monotherapy: 3-year follow-up

Alemtuzumab has been used in off-label studies of solid organ transplantation. We extend our report of the first 200 consecutive living donor solitary kidney transplantations under alemtuzumab pretreatment with tacrolimus monotherapy and subsequent spaced weaning to 3 years of follow-up. We focused especially on the causes of recipient death and graft loss, and the characteristics of rejection. The actuarial 1-, 2- and 3-year patient and graft survivals were 99.0% and 98.0%, 96.4% and 90.8% and 93.3% and 86.3%, respectively. The cumulative incidence of acute cellular rejection (ACR) at the following months was 2%</=6, 9.0%</=12, 16.5%</=18, 19.5%</=24, 23.5%</=30, 24.0%</=36 and 25%</=42. The mean serum creatinine (mg/dL) and glomerular filtration rate (mL/min/1.73 m(2)) at 1 and 3 years were 1.4 +/- 0.6 and 58.7 +/- 21.6 and 1.5 +/- 0.7 and 54.9 +/- 20.9, respectively. Fifty (25%) recipients had a total of 89 episodes of ACR. About 88.7% of ACR episodes were Banff 1, and of those, 82% were steroid-sensitive. Nine (4.5%) recipients had antibody-mediated rejection (AMR). About 76.5% were weaned but only 46% are currently on spaced dose (qod or less) tacrolimus monotherapy, and 94.4% remained steroid-free from the time of transplantation. Infectious complications were uncommon. This experience suggests the 3-year efficacy of this approach.

Pancreas transplant alone as an independent risk factor for the development of renal failure: a retrospective study

BACKGROUND

Pancreas transplant alone (PTA) is a controversial procedure. Without clearly demonstrated patient survival, recipients report improved quality of life. Nephrotoxic immunosuppression (IS) may exacerbate diabetic renal injury post-PTA.

METHODS

A single institution retrospective review of patients receiving PTA over a 14-year period was completed. Patient and donor demographics, surgical outcomes, rejection, and patient or graft survival were analyzed. Pre- and Postoperative estimated glomerular filtration rates (eGFR) were calculated based on the modification of diet and renal disease. Multivariate analysis was performed.

RESULTS

One hundred twenty-three patients undergoing 131 PTAs had an average age of 40.0 years. Seven patients were retransplanted and one received a third pancreas. Mean graft survival was 3.26 years (0-11.3 years) with 21 patients (17%) lost to follow-up. One- and 5-year patient survivals were 96.6% and 91.5%, respectively (mean, 7.15 year). Seventeen patients had an eGFR less than 50 mL/min/1.73 m preoperatively, whereas 64 patients did so post-PTA and 24 had an eGFR less than 30 mL/min. Mean eGFR pretransplantation was 88.9 vs. 55.6 posttransplantation (P<0.0001) with mean follow-up of 3.68 years. All but 16 (12%) patients showed a decrease in eGFR. Mean decrement was 32.1 mg/min/1.73 m. Thirteen developed end-stage renal disease chronic kidney disease (CKD 5) requiring kidney transplantation (KT) at a mean of 4.36 years. Eighty-three patients had an episode of rejection. In post-PTA RF, graft survival was 3.2 vs. 2.4 years (P=0.13). In those requiring KT, graft survival was 7.9 vs. 2.9 years (P<0.0001). Cold ischemia times, donor age, and preoperative eGFR for those with and without RF-requiring KT were not significant. Body mass index was statistically significant. Leukocyte-depleting agents was evaluated, but was not significant. All patients received calcineurin inhibitor IS.

CONCLUSIONS

Patients who undergo PTA may be at increased risk for RF. After comparing patient and donor demographics, IS, and human leukocyte antigen mismatch, it seems that PTA is an independent risk factor for the development of renal failure. Patients with more successful pancreatic grafts demonstrated lower eGFR. Patients should be made aware of the risks of long-term IS. Only the most appropriate patients should be chosen for PTA.

Advances in immunosuppression for pancreas transplantation

PURPOSE OF REVIEW

A review of current literature was performed to identify trends and evaluate outcomes with regard to clinical immunosuppression in pancreas transplantation.

RECENT FINDINGS

Through 2006, over 20 000 pancreas transplantations were performed in the US. Since 2000, the 1-year patient survival rates for the three pancreas transplantation categories--simultaneous pancreas-kidney, sequential pancreas after kidney, and pancreas alone--were 95-97% and the 1-year pancreas graft survival (complete insulin independence) rates were 85%, 78%, and 77%, respectively. One-year rates of rejection have steadily decreased and are currently in the 10-20% range depending on case mix and immunosuppressive regimen. At present, 88% of recipients receive antibody induction, 65% receive maintenance therapy with the tacrolimus/mycophenolate mofetil combination, and 40-50% undergo corticosteroid withdrawal without adverse consequences. Limited data with tacrolimus/sirolimus reveal excellent short-term outcomes, whereas initial attempts with calcineurin inhibitor avoidance or minimization are less promising.

SUMMARY

Antibody induction and either tacrolimus/mycophenolate mofetil or tacrolimus/sirolimus maintenance therapy with steroid withdrawal have become the mainstay of contemporary immunosuppression in clinical pancreas transplantation. The development of a nonnephrotoxic, nondiabetogenic, and nongastrointestinal toxic regimen, however, is highly desirable to improve outcomes and quality of life in recipients.

Alemtuzumab induction and steroid-free maintenance immunosuppression in pancreas transplantation

Alemtuzumab is a humanized anti-CD52 antibody that depletes lymphocytes and has been increasingly used as induction agent in transplantation. The impact of alemtuzumab induction immunosuppression in pancreas transplantation was evaluated, with particular reference to steroid avoidance in maintenance. A total of 100 patients who received 102 pancreas transplants (83 simultaneous kidney-pancreas [SPK], 15 pancreas after kidney transplantation [PAK] and 4 pancreas transplant alone [PTA]) were included. All patients received two doses of 30-mg alemtuzumab i.v. with tacrolimus (trough level 8-12 ng/mL) and mycophenolate mofetil (MMF,1g/day) with no maintenance steroids. This analysis included 62 male and 38 female recipients, with mean (+/-SD) age of 42 (+/-7.6) years. Median follow-up was 17 months (range 8-41 months). One-year patient, pancreas and kidney graft survival (actuarial) was 97%, 89% and 94%, respectively. Overall incidence of rejection was 25%. Side effects of alemtuzumab administration included thrombocytopenia (14%), pulmonary edema (2%) and rash (1%). Twenty-five percent required reoperations (12% for bleeding). Infectious complications included Cytomegalovirus (CMV,6.8%) BK viruria (3.8%), fungal infections (4%), primary varicella (1%) and posttransplant lymphoproliferative disorders (PTLD,1%). Eighty-three percent did not require any steroids posttransplant. These results indicate that alemtuzumab is safe and enables pancreas transplantation to be carried out without maintenance steroids in 83% of cases and acceptable rejection rate.

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.

Subcutaneous administration of alemtuzumab in simultaneous pancreas-kidney transplantation

Alemtuzumab (MabCampath, Campath-1H) is a potent lymphocyte-depleting monoclonal antibody increasingly used at induction in solid organ transplantation. Previously, it had been given by intravenous infusion; such administration is associated with a first-dose cytokine release syndrome characterized by fever and hypotension. Subcutaneous administration of alemtuzumab avoids this first-dose reaction while achieving a similar concentration to intravenous administration. The avoidance of infusion-associated hypotension is particularly important in pancreas transplantation where venous thrombosis is a major problem. We therefore treated 21 recipients of combined pancreas and kidney transplants with two 30-mg doses of alemtuzumab administered subcutaneously on days 0 and 1. No patient suffered a first-dose reaction. Lymphocyte depletion after subcutaneous alemtuzumab was profound and comparable to that seen in a group of renal transplant recipients who had received intravenous alemtuzumab. Subcutaneous alemtuzumab was associated with similar rates of acute rejection (14% at 1 year), patient survival (100%), and pancreas and kidney graft survival (95% and 100%, respectively) to those observed in centers using intravenous alemtuzumab in simultaneous pancreas kidney transplantation. There was no excess incidence of adverse events. We therefore recommend this route of administration to all transplant centers using alemtuzumab.

Novel approaches to therapy of hypereosinophilic syndromes

There has been recent progress in the understanding of the pathogenesis of the hypereosinophilic syndromes (HES). This led to the distinction of subgroups, in which the underlying cause has been identified. Consequently, new treatment options became available, such as imatinib and mepolizumab, which proved to be promising. This article summarizes these new pharmacologic approaches to the therapy of HES.

Pancreas transplantation under alemtuzumab (Campath-1H) and tacrolimus: Correlation between low T-cell responses and infection

BACKGROUND

Alemtuzumab induction and tacrolimus-based immunosuppression has been effective in pancreas transplantation. Despite the encouraging results of this minimalistic approach to immunosuppression, infection still remains a significant cause of morbidity. The Cylex ImmuKnow [corrected] assay was used in this study to compare pancreas recipient clinical states (stable, rejection, infection) with T cell responses.

METHODS

Blood samples were taken from pancreas recipients pretransplant and at approximately three-month intervals posttransplant for analysis of T cell responses. When possible, T cell responses were also quantified during changes in clinical status (infection or rejection).

RESULTS

A range between 100-300 ng/ml adenosine triphosphate (ATP) was found in stable patients (mean 194+/-123, n = 51) with good graft function and no infection or rejection. A low T cell response was highly correlated with infectious states. The fourteen patients with infections/posttransplant lymphoproliferative disease had a mean ATP of 48 ng/ml. Risk hazard analysis showed that patients with ATP levels <100 ng/ml were four to seven times more susceptible to infection compared to stable patients. Four patients with rejection showed a T cell response of 550 ng/ml ATP, which was statistically significant compared to stable patients, although the sampling numbers (9) were too small to be conclusive.

CONCLUSION

The Cylex ImmuKnow [corrected] assay is a valuable tool to more precisely modulate immunosuppression in pancreas transplant patients. In particular, the assay is extremely useful in detecting overly immunosuppressed patients vulnerable to infections.