Simultaneous cadaver pancreas living-donor kidney transplantation: a new approach for the type 1 diabetic uremic patient

Comparison of long-term outcomes in simultaneous pancreas-kidney transplant versus simultaneous deceased donor pancreas and living donor kidney transplant

Simultaneous deceased donor pancreas and living donor kidney transplant (SPLK) has certain advantages over conventional simultaneous pancreas-kidney transplant (SPK) and may be beneficial for overcoming the paucity of organs needed for diabetic patients requiring transplant. We compared the clinical outcomes of patients who underwent either SPK (n = 149) or SPLK (n = 46) in terms of pre- and post-transplantation variables, development of de novo DSA, occurrence of biopsy-proven acute rejection (BPAR), and graft survival rates. There were no significant differences in the baseline characteristics between the SPK and SPLK groups except for the shorter cold ischemic time of kidney grafts, shorter duration of diabetes, older age of pancreas graft-donors, and younger age of kidney graft-donors in the SPLK group. Our results showed that the death-censored pancreas graft survival rate was lower in the SPLK group. In addition, the incidence of BPAR of the pancreas graft was higher in the SPLK group. There was no significant difference in the presence of de novo DSA and the rates of kidney graft failure, kidney BPAR, and mortality. Our results show that SPLK can be considered an alternative option for SPK although higher incidences of BPAR and graft failure of pancreas after SPLK need to be overcome.

Survival benefit of the homologous kidney allograft in simultaneous pancreas-kidney transplants and its potential protective role

The superior death-censored graft survival of the pancreas allograft in simultaneous pancreas kidney transplants (SPK) over pancreas alone transplants (PTA) has long been recognized. Using data from the Scientific Registry of Transplant Recipients (SRTR) and a high-volume pancreas transplant program, we investigated the possible protective role of the kidney allograft in SPK transplants. We analyzed 19,043 primary pancreas transplants between 2000 and 2020, including 735 transplants performed at the University of Minnesota. SPK transplants demonstrated a superior death-censored graft survival over pancreas after kidney (PAK) and simultaneous pancreas and living donor kidney (SPLK) transplants, which both demonstrated better survival than PTA transplants. This effect was not affected by mode or duration of renal replacement therapy prior to transplant. Furthermore, we found that HLA match at the B-locus between the prior kidney and current pancreas allografts demonstrated a protective effect (HR 0.54; 95% confidence interval 0.29-1.00), with a 2-antigen match demonstrating superior death-censored graft survival to a 1- or 0-antigen match. We propose that a homologous kidney allograft in SPK transplants affords protection to the pancreas allograft - likely through a combination of better surveillance for rejection and direct immunoprotection offered by the same-donor kidney. This article is protected by copyright. All rights reserved.

Transplant Options for Patients With Diabetes and Advanced Kidney Disease: A Review

Optimal glycemic control in kidney transplant recipients with diabetes is associated with improved morbidity and better patient and allograft survival. Transplant options for patients with diabetes requiring insulin therapy and chronic kidney disease who are suitable candidates for kidney transplantation should include consideration of β-cell replacement therapy: pancreas or islet transplantation. International variation related to national regulatory policies exists in offering one or both options to suitable candidates and is further affected by pancreas/islet allocation policies and transplant waiting list dynamics. The selection of appropriate candidates depends on patient age, coexistent morbidities, the timing of referral to the transplant center (predialysis versus on dialysis) and availability of living kidney donors. Therefore, early referral (estimated glomerular filtration rate < 30 mL/min/1.73 m²) is of the utmost importance to ensure adequate time for informed decision making and thorough pretransplant evaluation. Obesity, cardiovascular disease, peripheral vascular disease, smoking, and frailty are some of the conditions that need to be addressed before acceptance on the transplant list, and ideally before dialysis becoming imminent. This review offers insights into selection of pancreas/islet transplant candidates by transplant centers and an update on posttransplant outcomes, which may have practice implications for referring nephrologists.

Solid pancreas transplant: Pushing forward

Pancreas transplant has evolved significantly in recent years. It has now become a viable treatment option on type 1 diabetic patients with poorly controlled diabetes on conventional treatment, insulin intolerance, hypoglycaemia unawareness, brittle diabetes and/ or end-stage kidney disease. The purpose of this review is to provide an overview of pancreas transplant historical origins and current barriers to broader utilization of pancreata for transplant, with a focus on areas for future improvement to better pancreas transplant care. Donor pancreata remain underutilized; pancreatic allograft discard rates remain close to 30% in the United States. Donations after cardiac death (DCD) pancreata are seldom procured. Study groups from Europe and the United Kingdom showed that procurement professionalization and standardization of technique, as well as development of independent regional procurement teams might increase organ procurement efficiency, decrease discards and increase pancreatic allograft utilization. Pancreas transplant programs should consider exploring pancreas procurement opportunities on DCD and obese donors. Selected type 2 diabetics should be considered for pancreas transplant. Longer follow-up studies need to be performed in order to ascertain the long-term cardiovascular and quality of life benefits following pancreas transplant; the outcomes of which might eventually spearhead advocacy towards broader application of pancreas transplant among diabetics.

Pancreas transplantation: Advantages of a retroperitoneal graft position

INTRODUCTION

In the 50 years since the first pancreas transplant performed at the University of Minnesota, the surgical techniques employed have undergone many modifications. Techniques such as retroperitoneal graft placement have further improved the ability to reproduce the physiology of the «native» pancreas. We herein present our experience of a modified technique for pancreatic transplant, with the organ placed into a fully retroperitoneal position with systemic venous and enteric drainage of the graft by duodeno-duodenostomy.

METHODS

All pancreas transplantations performed between May 2016 and January 2017 were prospectively entered into our transplant database and retrospectively analyzed.

RESULTS

A total of 10 transplants were performed using the retroperitoneal technique (6 men: median age of 41 years [IQR 36-54]). Median cold ischemia times was 10,30h [IQR 5,30-12,10]. The preservation solution used was Celsior (n=7), IGL-1 (n=2), and UW (n=1). No complications related to the new surgical technique were identified. In one patient, transplantectomy at 12h was performed due to graft thrombosis, probably related to ischemic conditions from a donor with prolonged cardio-respiratory arrest. Another procedure was aborted without completing the graft implant due to an intraoperative immediate arterial thrombosis in a patient with severe iliac atheromatosis. No primary pancreas non-function occurred in the remaining 8patients. The median hospital stay was 13,50 days [IQR 10-27].

CONCLUSIONS

Retroperitoneal graft placement appears feasible with easy access for dissection the vascular site; comfortable technical vascular reconstruction; and a decreased risk of intestinal obstruction by separation of the small bowel from the pancreas graft.

Advances in pancreas transplantation

The potential to reverse diabetes has to be balanced against the morbidity of long-term immunosuppression associated with transplantation. For a patient with renal failure, the treatment of choice is often a simultaneous transplant of the pancreas and kidney or pancreas after kidney. For a patient with glycaemic instability, choices between a solid organ or islet transplant have to be weighed against benefits and risks of remaining on insulin. Results of simultaneous transplant of the pancreas and kidney transplantation are comparable to other solid-organ transplants, and there is evidence of improved quality of life and life expectancy. There is some evidence of benefit with respect to the progression of secondary diabetic complications in patients with functioning transplants for several years.

Pancreas Transplantation: Past, Present, Future

Diabetes is the pandemic disease of the modern era, with 10% of these patients having type 1 diabetes mellitus. Despite the prevalence, morbidities, and associated financial burden, treatment options have not changed since the introduction of injectable insulin. To date, over 40,000 pancreas transplants have been performed globally. It remains the only known method for restoring glycemic control and thus curing type 1 diabetes mellitus. The aim of this review is to bring pancreatic transplantation out of the specialist realm, informing practitioners about this important procedure, so that they feel better equipped to refer suitable patients for transplantation and manage, counsel, and support when encountering them within their own specialty. This study was a narrative review conducted in October 2015, with OVID interface searching EMBASE and MEDLINE databases, using Timeframe: Inception to October 2015. Articles were assessed for clinical relevance and most up-to-date content, with articles written in English as the only inclusion criterion. Other sources used included conference proceedings/presentations and unpublished data from our institution (Oxford Transplant Centre). Pancreatic transplantation is growing and has quickly become the gold standard of care for patients with type 1 diabetes mellitus and renal failure. Significant improvements in quality of life and life expectancy make pancreatic transplant a viable and economically feasible intervention. It remains the most effective method of establishing and maintaining euglycemia, halting and potentially reversing complications associated with diabetes.

Three types of simultaneous pancreas and kidney transplantation

PURPOSE

The purposes of this study were to study and compare clinical and functional outcomes after simultaneous deceased donor pancreas and kidney transplantation (SPK DD), simultaneous deceased donor pancreas and living donor kidney transplantation (SPK DL), and simultaneous living donor pancreas and kidney transplantation (SPK LL).

METHODS

From January 1, 1996 to September 1, 2005, 8918 primary, simultaneous pancreas and kidney transplantation (SPK) procedures were reported to the International Pancreas Transplant Registry. Of these, 8764 (98.3%) were SPK DD, 115 (1.3%) were SPK DL, and 39 (0.4%) were SPK LL. We compared these 3 groups with regard to several endpoints including patient and pancreas and kidney graft survival rates.

RESULTS

The 1-year and 3-year patient survival rates for SPK DD were 95% and 90%, 97% and 95% for SPK DL, and 100% and 100% for SPK LL recipients, respectively (P ≥ .07). The 1-year and 3-year pancreas graft survival rates for SPK DD were 84% and 77%, 83% and 71% for SPK DL, and 90% and 84% for SPK LL recipients, respectively (P ≥ .16). The 1-year and 3-year kidney graft survival rates for SPK DD were 92% and 84%, 94% and 86% for SPK DL, and 100% and 89% for SPK LL recipients, respectively (P ≥ .37).

CONCLUSIONS

Patient survival rates and graft survival rates for pancreas and kidney were similar among the 3 groups evaluated in this study.

Imaging in pancreatic transplants

Pancreatic transplantation, performed alone or in conjunction with kidney transplantation, is an effective treatment for advanced type I diabetes mellitus and select patients with type II diabetes mellitus. Following advancements in surgical technique, postoperative management, and immunosuppression, pancreatic transplantation has significantly improved the length and quality of life for patients suffering from pancreatic dysfunction. While computed tomography (CT) and magnetic resonance imaging (MRI) have more limited utility, ultrasound is the preferred initial imaging modality to evaluate the transplanted pancreas; gray-scale assesses the parenchyma and fluid collections, while Doppler interrogation assesses vascular flow and viability. Ultrasound is also useful to guide percutaneous interventions for the transplanted pancreas. With knowledge of the surgical anatomy and common complications, the abdominal radiologist plays a central role in the perioperative and postoperative evaluation of the transplanted pancreas.

Endoscopic retrograde pancreatography using single balloon enteroscopy in a patient with smoldering pancreatitis in a distal jejunal pancreas transplant

Portal-enteric drainage of graft secretions is currently the preferred method of pancreatic transplantation and usually created between the donor duodenum and recipient jejunum; however, this anatomy does not allow for easy access to the donor pancreas. We report here the first case of a single balloon assisted-endoscopic retrograde pancreatography in a patient with progressively increasing amylase and lipase in portal-enteric-drained pancreas-kidney transplantation.

Treatment options for diabetes: potential role of stem cells

There are diseases and injuries in which a patient's cells or tissues are destroyed that can only be adequately corrected by tissue or organ transplants. Stem cells may be able to generate new tissue and even cure diseases for which there is no adequate therapy. Type 1 diabetes (T1DM), an insulin-dependent diabetes, is a chronic disease affecting genetically predisposed individuals, in which insulin-secreting beta (β)-cells within pancreatic islets of Langerhans are selectively and irreversibly destroyed by autoimmune assault. Type 2 diabetes (T2DM) is characterized by a gradual decrease in insulin sensitivity in peripheral tissues and the liver (insulin resistance), followed by a gradual decline in β-cell function and insulin secretion. Successful replacing of damaged β-cells has shown considerable potential in treating T1DM, but lack of adequate donors is a barrier. The literature suggests that embryonic and adult stem cells are promising alternatives in long-term treatment of diabetes. However, any successful strategy should address both the need for β-cell replacement and controlling the autoimmune response to cells that express insulin. This review summarizes the current knowledge of options and the potential of stem cell transplantation in diabetes treatment.

Evolution of β-Cell Replacement Therapy in Diabetes Mellitus: Pancreas Transplantation

Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide. According to the Centers for Disease Control and Prevention, approximately 23.6 million people in the United States are affected. Of these individuals, 5-10% have been diagnosed with type 1 diabetes mellitus (TIDM), an autoimmune disease. Although it often appears in childhood, T1DM may manifest at any age. The effects of T1DM can be devastating, as the disease often leads to significant secondary complications, morbidity, and decreased quality of life. Since the late 1960s, surgical treatment for diabetes mellitus has continued to evolve and has become a viable alternative to chronic insulin administration. In this review, the historical evolution, current status, graft efficacy, benefits, and complications of pancreas transplantation are explored.

Pancreatic transplantation: surgical technique, normal radiological appearances and complications

Pancreas transplantation is a surgical treatment for diabetes mellitus. More than 23,000 pancreas transplants have now been reported to the International Transplant Registry (IPTR). Early diagnosis and therapy for graft-related complications are essential for graft survival. Radiologists must therefore understand the surgical procedure and the potential complications. During the course of this review, we will illustrate the normal post-operative anatomy and the imaging appearances of common potential complications.

Pancreas transplant: recent advances and spectrum of features in pancreas allograft pathology

As result of improved surgical techniques and newer immunosuppressive regimens contributing significantly to better graft survival, exocrine pancreas transplantation remains the standard treatment of choice for patients with diabetes mellitus complicated by end-stage renal disease. Histologic assessment continues to play an important role in the diagnosis of graft complications after pancreas transplantation, especially for evaluating allograft rejection where histopathology is still considered the gold standard. This review elaborates on the current types of pancreas transplants and focuses on the patterns of allograft injury that are encountered in posttransplantation pancreas biopsies along with the pertinent differential diagnoses. In addition to optimal histologic assessment, as in any other organ transplant setting, clinical information including indication and duration of transplant as well as other serologic work-up must be taken into consideration during clinical decision making for optimal graft outcome.

Surgical techniques for pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation reproducibly induces insulin independence in beta-cell penic diabetic patients. The difference between full insulin independence, partial graft function, and graft loss, mostly results from technical failure, graft rejection, and patient death with function graft. The purpose of this review is to examine recent surgical advances and discuss their contribution to improved graft function.

RECENT FINDINGS

Few actual surgical innovations were described in the period reviewed. Duodenoduodenostomy is an interesting option for drainage of digestive secretions, when the pancreas is placed behind the right colon and is oriented cephalad. The main advantage of this technique is easy endoscopic assessment of donor duodenum but, when allograft pancreatectomy is necessary, repair of native duodenum may be troublesome. Selective revascularization of the gastroduodenal artery, at the back-table, possibly improves blood supply to the head of the pancreas graft and duodenal segment. There is no proof that this additional maneuver is always beneficial, although it can be graft saving in case of poor segmental graft perfusion.

SUMMARY

Transplant surgeons should be familiar with all techniques for pancreas transplantation. Long-term graft function is possible only after technically successful pancreas transplantation. There is clearly a need for more objective assessment and standardization of surgical techniques for pancreas transplantation.

Pancreas after living donor kidney transplants in diabetic patients: impact on long-term kidney graft function

In this single-institution study, we compared outcomes in diabetic recipients of living donor (LD) kidney transplants that did vs. did not undergo a subsequent pancreas transplant. Of 307 diabetic recipients who underwent LD kidney transplants from January 1, 1995, through December 31, 2003, a total of 175 underwent a subsequent pancreas after kidney (PAK) transplant; 75 were deemed eligible (E) for, but did not receive (for personal or financial reasons), a PAK, and thus had a kidney transplant alone (KTA); and 57 deemed ineligible (I) for a PAK because of comorbidity also had just a KTA. We analyzed the three groups (PAK, KTA-E, KTA-I) for differences in patient characteristics, glycemic control, renal function, patient and kidney graft survival rates, and causes of death. Kidney graft survival rates (actuarial) were similar in the PAK vs. KTA-E groups at one, five, and 10 yr post-transplant: 98%, 82%, and 67% (PAK) vs. 100%, 84%, and 62% (KTA-E) (p = 0.9). The long-term (greater than four yr post-transplant) estimated glomerular filtration rate (GFR) was higher in the PAK than in the KTA-E group: 53 +/- 20 mL/min (PAK) vs. 43 +/- 16 mL/min (KTA-E) (p = 0.016). The patient survival rates were also similar for the PAK and KTA-E groups. We conclude that the subsequent transplant of a pancreas after an LD kidney transplant does not adversely affect patient or kidney graft survival rates; in fact, it is associated with better long-term kidney graft function.

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.

Magnetic resonance imaging in pancreas transplantation

Magnetic resonance imaging (MRI) plays an important role in the evaluation of pancreas transplantation. Standard MRI, magnetic resonance angiography, and MR cholangiopancreatography can demonstrate the changes of the anatomy after transplantation. Vascular complications are assessed by MR angiography. Magnetic resonance cholangiopancreatography reveals ductal changes resulting from acute and/or chronic rejection and determines leaks with the use of a secretin-stimulated MR cholangiopancreatography. Serial contrast-enhanced MRI may detect the diminished perfusion that is related to the graft rejection or vascular complications. In this paper, we reviewed types of pancreas transplantation procedures, complications that arise in a short and/or a long term after the transplantation, and their assessment by MRI.

Ipsilateral portal enteric drained pancreas-kidney transplantation: a novel technique

In conventionally described simultaneous pancreas-kidney transplantation with portoenteric drainage, renal revascularization is derived from the left iliac vessels and pancreatic revascularization, from the right iliac artery. A newer technique utilizing the right iliac artery as a single inflow to both organs is described in six patients herein. The technique is less time-consuming and tedious than the standard method, which involves dissection of both iliac vessels. Advantages include shortened dissection time and preservation of the contralateral side for future use.

Pancreas transplantation

Over the last 5 years, there has been a resumed interest in treating diabetes by transplantation, particularly islet transplantation. However, despite advances being reported in Canada and the US, replication in the UK has been much more difficult. At present there is still only one treatment that can consistently reverse insulin independence in the long-term and that is whole pancreas transplantation. Long-term normoglycaemia has beneficial effects on preventing and ameliorating the secondary complications of diabetes and will be discussed.

[Experimental pancreatic islet transplant into the genito-urinary tract simultaneous to kidney transplant]

INTRODUCTION AND OBJECTIVES

Simultaneous kidney and pancreas transplant is a good treatment for both renal and pancreas insufficiency. Experimental apply of genitourinary tract for pancreas implantation is reported in this work.

MATERIAL AND METHOD

Twenty animals aged as average 5.5 monts (SD 1.1) and an average weight of 53 kgr were submitted to this protocol. In the day 1 a left nephrectomy is completed and the graft is perfused with University of Wisconsin solution. A partial pancreatectomy is completed at following, isolation of pancreatic islets by colagenase enzymatic digestion. Islets are dryed with Ditizone and culptured for 24 hours at 37 degrees C and 5% CO2. Day-2 a right nephrectomy is performed and orthotopic renal autotransplant using the left kidney is completed. Pancreatic islets are transplanted in 4 different locations of the genitourinary tract: renal subcapsular space, bladder submucosae, testis parenchyma and vas deferens. Day-7, all the animals were sacrifized to complete pathological study.

RESULTS AND CONCLUSIONS

Viable islets were isolated in bladder submucosae and testis after transdeferential injection.

Transplante de pâncreas e ilhotas em portadores de diabetes melito

O transplante simultâneo de pâncreas/rim tem indicações específicas, riscos e benefícios. O procedimento, cada vez mais realizado, traz vantagens se comparado ao paciente em diálise, em relação à qualidade de vida, anos de vida ganhos e evolução das complicações crônicas. Se o paciente tiver a opção de realizar o transplante de rim com doador vivo, que apresenta sobrevida semelhante do enxerto e do paciente aos dez anos, o procedimento deverá ser considerado. O transplante de pâncreas após rim, quando efetivo, pode melhorar a evolução das complicações cardiovasculares, mas em contrapartida provoca maior mortalidade nos primeiros meses após a cirurgia. O transplante isolado de pâncreas também ocasiona a maior mortalidade pós-operatória, resultado da complexidade do procedimento e da imunossupressão. O transplante de ilhotas tem sua indicação para um seleto grupo de diabéticos com instabilidade glicêmica.

Kidney-pancreas transplantation: single-center experience at a university hospital in Turkey

INTRODUCTION

One treatment option for patients with type 1 diabetes mellitus with end-stage nephropathy is combined pancreas-kidney transplantation, which can be performed either simultaneously (SPK) or following kidney transplantation (PAK).

PATIENTS AND METHODS

Between February 2003 and November 2004, 14 patients, including 10 males and 4 females of overall mean age of 31.3 +/- 6.1 years (range, 23-44 years), presented with end-stage renal disease secondary to type 1 diabetes mellitus. Five patients (35.7%) received SPK; 7 patients (50%) received PAK; and 2 patients (14.3%) received simultaneous pancreas and living-related kidney (SPLK) transplantations.

RESULTS

Two among 14 pancreas grafts were lost in the early postoperative period secondary to venous thrombosis despite anticoagulation including 1 with poor portal drainage. Insulin therapy was reinitiated in 1 patient after a second rejection episode in the seventh postoperative month. By the ninth median follow-up month (range, 1-21 months), all kidney grafts were functioning.

CONCLUSION

Our single-center short-term experience with 14 consecutive kidney-pancreas transplantations suggests that while the pancreas transplant is effective and safe to reestablish normoglycemia, this transplant creates additional surgical and immunosuppressive stresses on the patient.

Surgical nuances in pancreas transplantation

The modern surgical era of vascularized pancreas transplantation (PTX) began with the systemic-bladder drainage technique. According to International Pancreas Transplant Registry (IPTR) data, most PTX procedures are performed with systemic venous delivery of insulin and either bladder (systemic bladder) or enteric (systemic-enteric) drainage of the exocrine secretions. Since 1995 the number of PTX procedures performed with primary enteric drainage has increased dramatically, accounting for more than 70% of cases since 2001. Despite an evolution in exocrine drainage, the proportion of enteric drained PTXs with portal venous delivery of insulin (portal enteric drainage) has remained low, representing about 20% of cases. In recent IPTR analyses no differences were reported in short-term outcomes according to surgical technique. Coincident with more physiologic implantation techniques, the surgical complication rate has decreased to 10% to 20%. Experience with donor and recipient selection can reduce morbidity, inasmuch as risk factors for surgical complications include prolonged pre-transplantation peritoneal dialysis, donor or recipient BMI body mass index >28 kg/m2, donor or recipient age older than 45 years, cerebrovascular cause of donor brain death, prolonged preservation, and prior abdominal surgery in the recipient. New techniques include simultaneous living donor kidney and deceased donor PTX, gastroduodenal artery revascularization, laparoscopic living donor nephrectomy and distal pancreatectomy, en bloc kidney and pancreas transplantation, P-E drainage with venting jejunostomy, retroperitoneal PTX with P-E drainage, and unusual vascular grafts. In the future the emphasis will shift from short-term surgical to long-term medical outcomes as the ultimate measure of success.

A technique for retroperitoneal pancreas transplantation with portal-enteric drainage

BACKGROUND

Pancreas transplantation (PTx) with portal-enteric drainage (PED) has been associated with difficulties in respect to arterial anastomosis and graft accessibility for percutaneous biopsy. We describe a new technique that circumvents these difficulties.

METHODS

Between April 2001 and April 2004, a total of 113 recipients were scheduled for PTx with PED. The superior mesenteric vein was approached from the right retroperitoneal aspect instead of from the anterior transmesenteric route. The pancreas graft was eventually placed in the right retroperitoneal space, being covered by the ascending colon and its mesentery.

RESULTS

One hundred ten (97.3%) PTx were performed as planned. Systemic venous effluent was preferred in three patients because of incidental diagnosis of liver cirrhosis during surgery (n=1) and severe obesity (body mass index>35 kg/m2) (n=2). The Y iliac artery graft was kept as short as possible, and arterial anastomosis was always performed with ease. After a mean follow-up period of 21.2+/-19.9 months, the relaparotomy rate was 13.6%. No patient died after repeat surgery, and none required multiple relaparotomies. Overall, 10 grafts were lost because of acute rejection (n=3), chronic rejection (n=2), venous thrombosis (n=2), recipient death (n=2), and late (6-month) arterial thrombosis (n=1). One-year patient and graft survival were 98.1% and 90.7%, respectively.

CONCLUSIONS

Our data confirm that PTx with PED is not associated with an increased risk. The technique described has distinctive technical advantages and should be included in the repertoire of PTx.

Long-term survival after kidney and kidney-pancreas transplantation in diabetic patients

PURPOSE

To investigate the influence of diabetes mellitus on patient and graft survival among renal versus renal-pancreatic recipients.

METHODS

Among 270 renal transplants performed from 1985 to 2002, a total of 204 (75%) were in diabetic patients and 66 (25%) in nondiabetic patients. Among the 204 diabetic patients 161 (60%) kidneys were transplanted simultaneously with a pancreatic graft (SKPT group). The overall group of patient included 164 (61%) men and 106 (39%) women with mean time on dialysis of 31 +/- 21 months (range 0 to 126 months). The mean duration of diabetes was 24 +/- 7 years (range 5 to 51 years). Ninety-nine percent of the patients were on renal replacement therapy (79% hemodialysis and 20% peritoneal dialysis).

RESULTS

The overall rejection rate was similar (NS). Both patient and kidney graft survival rates were worse in diabetics. Patient survival was 82% at 5 years among patients undergoing SKPT, 60% in diabetics receiving only a kidney, and 88% in nondiabetic transplanted patients. Kidney graft survival at 5 years was 77% in diabetics receiving SKPT, 68% in diabetics receiving a kidney alone, and 82% in nondiabetic patients. Overall patient survival was significantly greater among nondiabetics (P =.002) or in diabetics who received SKPT compared with diabetics who only had a kidney transplant (P =.001).

CONCLUSIONS

This retrospective clinical evaluation confirms that combined pancreas and kidney transplantation should be the first choice to insulin-dependent diabetes mellitus (IDDM) patients with end-stage diabetic nephropathy.

Pancreas transplantation: indications and consequences

Pancreas transplantation continues to evolve as a strategy in the management of diabetes mellitus. The first combined pancreas-kidney transplant was reported in 1967, but pancreas transplant now represents a number of procedures, each with different indications, risks, benefits, and outcomes. This review will summarize these procedures, including their risks and outcomes in comparison to kidney transplantation alone, and how or if they affect the consequences of diabetes: hyperglycemia, hypoglycemia, and microvascular and macrovascular complications. In addition, the new risks introduced by immunosuppression will be reviewed, including infections, cancer, osteoporosis, reproductive function, and the impact of immunosuppression medications on blood pressure, lipids, and glucose tolerance. It is imperative that an endocrinologist remain involved in the care of the pancreas transplant recipient, even when glucose is normal, because of the myriad of issues encountered post transplant, including ongoing management of diabetic complications, prevention of bone loss, and screening for failure of the pancreas graft with reinstitution of treatment when indicated. Although long-term patient and graft survival have improved greatly after pancreas transplant, a multidisciplinary team is needed to maximize long-term quality, as well as quantity, of life for the pancreas transplant recipient.

Stimulation of in vivo angiogenesis by cytokine-loaded hyaluronic acid hydrogel implants

Crosslinked hyaluronic acid (HA) hydrogels were evaluated for their ability to elicit new microvessel growth in vivo when preloaded with one of two cytokines, vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF). HA film samples were surgically implanted in the ear pinnas of mice, and the ears retrieved 7 or 14 days post implantation. Histologic analysis showed that all groups receiving an implant demonstrated significantly more microvessel density than control ears undergoing surgery but receiving no implant (p < 0.01). Moreover, aqueous administration of either growth factor produced substantially more vessel growth than an HA implant with no cytokine. However, the most striking result obtained was a dramatic synergistic interaction between HA and VEGF. Presentation of VEGF in crosslinked HA generated vessel density of NI = 6.7 at day 14, where NI is a neovascularization index defined below, more than twice the effect of the sum of HA alone (NI = 1.8) plus VEGF alone (NI=1.3). This was twice the vessel density generated by co-addition of HA and bFGF (NI=3.4, p<0.001). New therapeutic approaches for numerous pathologies could be notably enhanced by the localized, synergistic angiogenic response produced by release of VEGF from crosslinked HA films.

Simultaneous pancreas-kidney transplantation is improved by living kidney donation program

BACKGROUND

Shortage of suitable donors and current graft allocation priorities reduce the number of cadaveric kidneys available to diabetic recipients. The concurrent excess of solitary cadaveric pancreata and the excellent results of living kidney transplantation make simultaneous cadaveric pancreas-living kidney transplantation (SPLKTx) an attractive alternative to simultaneous pancreas-kidney transplantation (SPKTx).

METHODS

Between June 2001 and June 2003, 80 recipients were enrolled in the SPKTx waiting list. Each recipient's family was counseled about living kidney donation (LKD). Twenty-nine (36.2%) candidates were evaluated for LKD and 8 (27.6%) were disqualified. The remaining 21 candidates were scheduled for LKD and 18 actually donated.

RESULTS

Thanks to LKD 18 additional recipients were transplanted, thus expanding the donor pool from 33 to 51 (P =.004). The median waiting time for SPLKTx was 14 days as compared with 95 days for SPKTx (P =.006). Without LKD the median waiting time for SPKTx would have been 198 days (P =.02). Similarly, 1 year after the enrollment on the waiting list 60% of recipients had been transplanted, while without LKD only 42% would had been grafted (P =.01). Two-year recipient survival rate was 100% for SPLKTx compared with 96.9% for SPKTx. Equivalent figures for kidney and pancreas were 80.0% and 84.0% for SPLKTx compared with 96.9% and 96.9% for SPKTx.

CONCLUSIONS

LKD expanded the kidney donor pool, reduced the waiting time of recipients listed for a totally cadaveric procedure, and increased their chance to get a timely graft. One-year outcome of SPLKTx equaled that of SPKTx.

Simultaneous cadaver pancreas–living donor kidney transplantation

BACKGROUND

The expansion of the donor pool achieved with living kidney donation (LKD) is particularly beneficial for diabetic patients, who have a worse prognosis during dialysis when compared to other kidney recipients. Simultaneous cadaver pancreas-living kidney transplantation (SPLKTx) merges the advantages of LKD with those of cadaver donation, and may be an attractive alternative to simultaneous pancreas kidney transplantation (SPKTx).

METHODS

The outcomes of 18 SPLKTx were compared with those of 33 SPKTx.

RESULTS

LKD expanded the donor pool from 33 to 51 (P =.004). Median wait time was shorter for SPLKTx (14 days) than for SPKTx (95 days) (P =.006). The risk for surgical complications was not increased by SPLKTx, as witnessed by relaparotomy rates (SPLKTx: 2/18, 11.1%; SPKTx: 2/33, 6.1%; P >.05). Hospital stay averaged 26.1 +/- 11.2 days for SPLKTx and 27.1 +/- 16.3 for SPKTx (P >.05) with equivalent 30-day readmission rates (SPLKTx: 5.5%; SPKTx: 6.1%); (P >.05). One acute kidney rejection occurred in SPLKTx (5.5%) as compared with four in SPKTx (12.1%); (P >.05). Equivalent rates for the pancreas were 5.5% (1/18) for SPLKTx and 3.0% (1/33) for SPKTx (P >.05). Two-year recipient survival rates were 100% for SPLKTx as compared with 96.9% for SPKTx. Equivalent figures for kidney and pancreas were 80.0% and 84.0% for SPLKTx and 96.9% and 96.9% for SPKTx.

CONCLUSIONS

SPLKTx is a valuable alternative to SPKTx. Further development of SPLKTX relies on increased rates of living kidney donation.

Pancreas-after-kidney transplantation: an increasingly attractive alternative to simultaneous pancreas-kidney transplantation

BACKGROUND

Historically, the clinical acceptability of pancreas-after-kidney (PAK) transplantation has been hampered by relatively high acute rejection rates and lower pancreas graft survival rates when compared with the more commonly performed simultaneous pancreas-kidney (SPK) transplantation. The purpose of this study was to compare PAK transplantation to SPK transplantation in the Thymoglobulin induction era.

METHODS

The authors reviewed all bladder-drained PAK (n=47) transplants receiving rabbit antithymocyte globulin induction from June 1998 to June 2002 and compared them with SPK (n=25) transplants during the same time period at their institution. The authors retrospectively studied data on demographics, patient survival, graft (pancreas and kidney) survival, complications, and biopsy-proven rejection episodes.

RESULTS

The actuarial 1-year patient survival was 93% for the PAK group versus 100% for the SPK group (P =not significant [NS]). The actuarial 1-year pancreas graft survival was 87% for the PAK group versus 92% for the SPK group (P =NS). Waiting time for PAK was significantly shorter than for SPK (6.3 +/- 5.2 vs. 16.2 + -13.7 months, P <0.05). Clinical acute rejection rates were similar in the two groups (4.3% for PAK vs. 4.0% for SPK). PAK recipients demonstrated a greater decline in renal function after transplantation compared with SPK. A multivariate analysis failed to elucidate the cause.

CONCLUSIONS

Newer immunosuppressive regimens allow PAK transplant patients to achieve immunologic outcomes similar to SPK transplant patients. Although the shorter waiting time and the ability to use living-donor kidneys make PAK an increasingly attractive alternative to SPK transplantation, its effect on renal allograft function deserves further attention.

Incidence, timing and site of infections among pancreas transplant recipients

The incidence, timing and site of infections among the different categories of pancreas transplant recipients were investigated. Patients were divided into three groups: pancreas transplant alone (PTA), pancreas after kidney transplant (PAK), or simultaneous pancreas and kidney (SPK) transplants. Length of follow-up, time to death, pancreas graft survival, incidence, timing and site of bacterial infections were noted. Our study showed that at least 75% of pancreas transplant recipients experienced at least one infection (range from 77.8% in the PTA group to 86.7% in the PAK group). The SPK group presented the highest rate of infections with 35.1 infections per 1000/patient-days. Symptomatic urinary tract infections were the most common cause of infection in all patients. The incidence of infections was higher during the first month after transplantation, except for the SPK transplant group, where infections occurred over a longer time period.

Laparoscopic donor nephrectomy: the University of Maryland 6-year experience

PURPOSE

We determined whether the results of laparoscopic donor nephrectomy warranted expansion of the availability of the technique.

MATERIALS AND METHODS

Donor and recipient charts for 738 consecutive laparoscopic living donor nephrectomies have been reviewed.

RESULTS

Renal donors were 69% white race and 57% female. Age range was 18 to 74 years. Neither age nor obesity alone were exclusionary criteria. Nephrectomy was left sided in 96%. Donors with body mass index greater than 33 had longer operative times. The extraction site changed from umbilical to suprapubic during the series. Warm ischemia time was 169 seconds. Conversion to open nephrectomy occurred in 1.6% of cases and blood transfusion was required in 1.2%. Major intraoperative complications occurred in 6.8% and major postoperative complications occurred in 17.1% of cases. Hospitalization lasted 64.4 hours. Postoperative donor creatinine was 1.5 times the preoperative level. Recipient serum creatinine averaged 2.0 mg% at 1 week and 1.6 mg% at 1 year. Delayed graft function occurred in 2.6%. However, 9.1% of recipients did not achieve a serum creatinine less than 3.0 mg% within 7 days. The endovascular stapler also created 37 extra arteries for implantation.

CONCLUSIONS

Risks of laparoscopic donor nephrectomy to the donor must not be minimized. Rapid conversion to open surgery to control bleeding may be necessary. Nonvascular intraoperative injuries require recognition. Slow bowel function recovery prolongs hospitalization and may indicate unrecognized pancreatitis or small bowel herniation. Surgical technique and complication management have improved. Laparoscopic donor nephrectomy is now routine but still requires an intense level of attention to prevention of complications.

Chronic rejection: the next major challenge for pancreas transplant recipients

OBJECTIVE

With newer immunosuppressive agents, acute rejection and graft loss resulting from acute rejection have become less common for pancreas transplant recipients. As long-term graft survival rates have improved, an increasing number of grafts are being lost to chronic rejection (CR). We studied the incidence of CR and identified risk factors.

METHODS

We retrospectively analyzed all cadaver pancreas transplants performed at the University of Minnesota between June 19, 1994, and December 31, 2002. We determined the causes of graft loss, the incidence of graft loss to CR and, using multivariate techniques, the major risk factors for CR.

RESULTS

A total of 914 cadaver pancreas transplants were performed in the following three categories: simultaneous pancreas-kidney (SPK) (n=321), pancreas after kidney (PAK) (n=389), and pancreas transplant alone (PTA) (n=204). The mean recipient age was 41.3 years and the mean donor age was 30.1 years. Of the 914 pancreas grafts, 643 (70.3%) continue to function (mean length of follow-up, 39 months). The most common cause of graft loss was technical failure, accounting for 118 (12.9%) of the failed grafts. The second most common cause was CR, accounting for 80 (8.8%) of the failed grafts. The incidence of graft loss to CR was highest for PTA (n=23 [11.3%]) and PAK (n=45 [11.6%]) recipients and lowest for SPK recipients (n=12 [3.7%]) (P=0.002). By multivariate analysis, the most significant risk factors for graft loss to CR were a previous episode of acute rejection (relative risk [RR]=4.41, P<0.0001), an isolated (vs. simultaneous) transplant (PAK or PTA [vs. SPK], RR=3.02, P=0.002), cytomegalovirus infection posttransplant (RR=2.41, P=0.001), a retransplant (versus primary transplant) (RR=2.27, P=0.004), and one or two (vs. zero) antigen mismatches at the B loci (RR=1.68, P=0.04).

CONCLUSIONS

As short-term pancreas transplant results improve and as isolated (PAK or PTA) pancreas transplants gain in popularity, CR will become increasingly common as a cause of pancreas graft loss.

Simultaneous pancreas-kidney transplant from living related donor: a single-center experience

BACKGROUND

Simultaneous pancreas and kidney transplantation (SPK) from cadaveric donors has become a widely accepted therapeutic option for insulin-dependent uremic patients. In 1996 the first SPK from a live donor was performed. This procedure offers the advantage of a better immunologic match, reduced cold ischemia injury, and decreased waiting time. As such, it is an attractive alternative treatment for diabetic patients with end-stage nephropathy with an available living donor.

METHODS

We performed six SPKs from living-related donors. There were four men and two women among the recipients; median age was 34 (range, 29-39) years. All donors were recipients' siblings with excellent HLA matching. Donors underwent standardized metabolic workup, anti-insulin and anti-islet antibody assays, and computed tomography of the abdomen. Both donors and recipients were treated with octreotide for 5 days perioperatively. After transplantation, the patients were maintained on tacrolimus-based immunosuppression, with the exception of one recipient of SPK from an identical twin, who received cyclosporine monotherapy.

RESULTS

All the donors are doing well and have normal renal function and blood glucose levels. One-year patient, renal, and pancreatic graft survival rates were 100%, 100%, and 83%, respectively. Acute kidney rejection was documented in two patients, and both recovered completely after OKT3 therapy. No rejection of pancreatic graft has been documented. Except for one patient who lost the graft because of hemorrhagic pancreatitis, all recipients maintained serum glucose levels at less than 130 mg/dL without insulin therapy. No major surgical complications such as graft thrombosis, intra-abdominal infection, or abscess were reported.

CONCLUSIONS

Living donor SPK can represent a successful alternative to cadaveric donor SPK. The procedure can be performed safely in the donor and with low morbidity in the recipient.

Bio-engineering inslulin-secreting cells from embryonic stem cells: a review of progress

According to the Edmonton protocol, human islet transplantation can result in insulin independency for periods longer than 3 years. However, this therapy for type 1 diabetes is limited by the scarcity of cadaveric donors. Owing to the ability of embryonic stem cells to expand in vitro and differentiate into a variety of cell types, research has focused on ways to manipulate these cells to overcome this problem. It has been demonstrated that mouse embryonic stem cells can differentiate into insulin-containing cells, restoring normoglycaemia in diabetic mice. To this end, mouse embryonic stem cells were transfected with a DNA construct that provides resistance to neomycin under the control of the regulatory regions of the human insulin gene. However, this protocol has a very low efficiency, needing improvements for this technology to be transferred to human stem cells. Optimum protocols will be instrumental in the production of an unlimited source of cells that synthesise, store and release insulin in a physiological manner. The review focuses on the alternative source of tissue offered by embryonic stem cells for regenerative medicine in diabetes and some key points that should be considered in order for a definitive protocol for in vitro differentiation to be established.