Results of pancreas transplantation with portal venous and enteric drainage

Ultrasound of pancreatic transplant complications: a primer for radiologists

Pancreatic transplantation is an established treatment for patients with type 1 diabetes patients and select type 2 diabetes patients, with excellent survival rates as graft health is evaluated through regular imaging and early detection of complications. Amongst the various imaging methods that may aid in diagnosis of pancreatic transplant complications, ultrasound is a widely available, quick, portable, and cost-effective technique, often used as the sole method to assess for pancreatic transplant complications. When assessing a patient with a pancreatic transplant, the radiologist should be methodical in assessing the vasculature, the pancreatic parenchyma, and the peripancreatic regions. Complications can be categorised based on time from transplant and type of complications, and include vascular, parenchymal, and enteric/anastomotic complications. Doppler has a major role in the diagnosis of vascular complications including arterial and venous thrombosis, arterial stenosis, pseudoaneurysms, and haematomas. Pancreatic complications include rejections and pancreatitis, and are often diagnosed through a combination of clinical, laboratory, and imaging findings, such as pancreatic heterogeneity or the presence of pancreatic pseudocysts. Enteric/anastomotic complications include leaks and bowel obstructions, and may require cross-sectional imaging in addition to ultrasound. This review covers the most common and high-impact vascular, parenchymal, and enteric/anastomotic complications that should be considered in every radiologist's search pattern when assessing a pancreatic graft, as well as their respective postoperative timeframes.

The influence of simultaneous pancreas-kidney transplantation on the evolution of diabetic foot lesions and peripheral arterial disease

PURPOSE

Simultaneous pancreas-kidney transplantation (SPKT) remains the best treatment option in patients with type 1 diabetes and chronic kidney failure. There are only a few studies addressing the potential ischemic deterioration of peripheral arterial disease (PAD) due to blood diverting from the iliac artery to the kidney graft. We aimed to evaluate diabetic foot lesions and PAD evolution in SPKT recipients and investigate if they are more frequent in ipsilateral lower limb of kidney graft.

METHODS

We developed a retrospective cohort, including patients submitted to SPKT in our tertiary center, between 2000 and 2017. Diabetic foot lesions and PAD frequencies were compared in the period before and after transplantation.

RESULTS

Two hundred and eleven patients were included, 50.2% (n = 106) female, with a median age at transplantation of 35 years (IQR 9). After a median follow-up period of 10 years (IQR 7), patient, kidney, and pancreatic graft survival were 90.5% (n = 191), 83.4% (n = 176), and 74.9% (n = 158), respectively. Before transplant, 2.8% (n = 6) had PAD and 5.3% (n = 11) had history of foot lesions. In post-transplant period, 17.1% (n = 36) patients presented PAD and 25.6% (n = 54) developed diabetic foot ulcers, 47.6% (n = 35) of which in the ipsilateral and 53.3% (n = 40) in the contralateral lower limb of the kidney graft (p = 0.48). Nine patients (4.3%) underwent major lower limb amputation, 3 (30%) ipsilateral and 7 (70%) contralateral to the kidney graft (p = 0.29).

CONCLUSIONS

Diabetic foot lesions were not more frequent in the ipsilateral lower limb of the kidney graft, therefore downgrading the 'steal syndrome' role in these patients.

A case report of percutaneous direct injection of N-butyl-2-cyanoacrylate (NBCA) to treat a pancreatic duodenal stump leak after a simultaneous pancreas and kidney transplantation

BACKGROUND

Simultaneous pancreas and kidney transplantation (SPK) is a treatment option for patients with end-stage renal disease due to type 1 diabetes mellitus. We report a patient with a refractory fistula due to leakage from the duodenal stump of the pancreas graft after an SPK with bladder drainage who was successfully treated with a percutaneous direct injection of N-butyl-2-cyanoacrylate (NBCA).

CASE PRESENTATION

A 60-year-old female with a 33-year history of type 1 diabetes mellitus and a 10-year history of renal replacement therapy underwent an SPK in 2015. At the time of transplantation, an abdominal aortic aneurysm with a high risk of rupture was treated by a Y-graft replacement prior to the SPK. Bladder drainage of the pancreas graft was chosen to avoid a vessel graft infection. The patient's postoperative course was uneventful. The patient was discharged on postoperative day 93 with good-functioning pancreas and kidney grafts. One and a half years after the operation, the patient was found to have acute graft pancreatitis and a leak from the duodenal stump of the pancreas graft due to a paralytic neurogenic bladder. The insertion of an indwelling catheter into the bladder and the endoscopic-guided insertion of a catheter into the graft pancreatic duct through the duodenum/bladder anastomosis did not result in the closure of the fistula. Therefore, NBCA was injected at the site of the leak point using CT-guided technique. The fistula was completely closed immediately after the injection, with no recurrences of leaks.

CONCLUSIONS

A percutaneous direct injection of NBCA is one of the treatment options to treat intractable fistulas.

Effects of simultaneous pancreas-kidney transplantation and kidney transplantation alone on the outcome of peripheral vascular diseases

Background

The effects of Simultaneous Pancreas Kidney Transplantation (SPKT) on Peripheral Vascular Disease (PVD) warrants additional study and more target focus, since little is known about the mid- and long-term effects on the progression of PVD after transplantation.

Methods

101 SPKT and 26 Kidney Transplantation Alone (KTA) recipients with insulin-dependent diabetes mellitus (IDDM) were retrospectively evaluated with regard to graft and metabolic outcome. Special subgroup analysis was directed towards the development and progression of peripheral vascular complications (PVC) (amputation, ischemic ulceration, lower extremity angioplasty/ bypass surgery) after transplantation.

Results

The 10-year patient survival was significantly higher in the SPKT group (SPKT: 82% versus KTA 40%; P < 0.001). KTA recipients had a higher prevalence of atherosclerotic risk factors, including coronary artery disease (P < 0.001), higher serum triglyceride levels (P = 0.049), higher systolic (P = 0.03) and diastolic (P = 0.02) blood pressure levels. The incidence of PVD before transplantation was comparable between both groups (P = 0.114). Risk factor adjusted multivariate analysis revealed that patients with SPKT had a significant lower amount (32%) of PVCs (32 PVCs in 21 out of 101 SPKT; P < 0.001) when compared to the KTA patients who developed a significant increase in PVCs to 69% of cases (18 PVCs in 11 out of 26 KTA; P < 0.001). In line mean values of HbA_1c (P < 0.01) and serum triglycerides (P < 0.01) were significantly lower in patients with SPKT > 8 years after transplantation.

Conclusion

SPKT favorably slows down development and progression of PVD by maintaining a superior metabolic vascular risk profile in patients with IDDM1.

Surgery of pancreas transplantation

PURPOSE OF REVIEW

The surgical techniques of pancreas transplantation have been evolving and significantly improved over time. This article discusses different current techniques and their modifications.

RECENT FINDING

At this time, the most commonly used technique is systemic venous drainage (for venous outflow) and enteric drainage (for management of exocrine pancreatic secretions). However, new modifications of established techniques such as gastric or duodenal exocrine drainage and venous drainage to the inferior vena cava continue to be introduced.

SUMMARY

This article provides a state-of the-art review of the most prevalent up-to-date surgical techniques as well as a synopsis of their specific risks and benefits. The article also provides the most current registry data regarding utilization of different surgical techniques in the United State and worldwide.

Pancreas Transplantation With Portal-Enteric Drainage for Patients With Endocrine and Exocrine Insufficiency From Extensive Pancreatic Resection

Although the primary indication for pancreas transplantation is type I diabetes, a small number of patients requires pancreas transplantation to manage combined endocrine and exocrine insufficiency that develops after extensive native pancreatic resection. The objective of this case report was to describe the operative and clinical course in 3 such patients and present an alternative technical approach.

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.

Vasculogenic hydrogel enhances islet survival, engraftment, and function in leading extrahepatic sites

Islet transplantation is a promising alternative therapy for insulin-dependent patients, with the potential to eliminate life-threatening hypoglycemic episodes and secondary complications of long-term diabetes. However, widespread application of this therapy has been limited by inadequate graft function and longevity, in part due to the loss of up to 60% of the graft in the hostile intrahepatic transplant site. We report a proteolytically degradable synthetic hydrogel, functionalized with vasculogenic factors for localized delivery, engineered to deliver islet grafts to extrahepatic transplant sites via in situ gelation under physiological conditions. Hydrogels induced differences in vascularization and innate immune responses among subcutaneous, small bowel mesentery, and epididymal fat pad transplant sites with improved vascularization and reduced inflammation at the epididymal fat pad site. This biomaterial-based strategy improved the survival, engraftment, and function of a single pancreatic donor islet mass graft compared to the current clinical intraportal delivery technique. This biomaterial strategy has the potential to improve clinical outcomes in islet autotransplantation after pancreatectomy and reduce the burden on donor organ availability by maximizing graft survival in clinical islet transplantation for type 1 diabetes patients.

Pancreatic Transplantation: Evaluation and Management

More than 2 million people in the United States have type 1 diabetes mellitus. Pancreatic transplantation has emerged as the single most effective means of achieving normal glucose homeostasis in this patient population. Newer immunosuppressive agents and surgical techniques continue to evolve, resulting in improved long-term graft and patient survival. Herein, an understanding of the evaluation, technical aspects, and perioperative management of pancreas transplantation is outlined.

Pancreas Transplantation in the Modern Era

The field of pancreas transplantation has evolved from an experimental procedure in the 1980s to become a routine transplant in the modern era. With short- and long-term outcomes continuing to improve and the significant mortality, quality-of-life, and end-organ disease benefits, pancreas transplantation should be offered to more patients. In this article, we review current indications, patient selection, surgical considerations, complications, and outcomes in the modern era of pancreas transplantation.

Short and long-term outcomes of systemic drainage to IVC: a new technique for pancreas transplantation

Ninety-eight percent of the whole pancreas does not serve the purpose of pancreatic transplantation and it is a major cause of surgical complications. Up to 30% of pancreas transplant recipients experience surgical complications and require reoperation. Graft thrombosis and pancreatitis are the most common complications of pancreas transplantation (PT). Thus, different surgical techniques have been described to overcome the surgical hurdles and reduce surgical complications. In this study, for the first time, we report short- and long-term outcomes of PT with inferior vena cava (IVC) venous drainage. Forty-five PTs (22 simultaneous pancreas and kidney [SPK] transplantations and 23 pancreas after kidney [PAK] transplantations) were performed with this technique in our center. Sixty-eight percent of the donors were imported from outside of our area after they were declined by their local transplantation center. Patient and graft survival rates were 100% at 1 year. No graft thrombosis or pancreatitis occurred with this technique. Six patients (13.3%) required reoperation (3 bleeding, 2 anastomotic leak, and 1 small bowel perforation). No patient or graft loss occurred due to surgical complications. We conclude that this technique provides fast and easy dissection of the venous drainage of the PT without the need of complete occlusion of venous outflow. Surgical complication rates were lower with this technique compared with other reported techniques.

A comparison of long-term outcomes of portal versus systemic venous drainage in pancreatic transplantation: a systematic review and meta-analysis

Pancreas transplantation venous effluent can be drained via the portal vein or the systemic circulation; however, no recommendation exists for the ideal technique. A systematic review of the literature from 1989 through 2014 using PubMed, CINHAL, and Cochrane Library for portal versus systemic venous drainage was undertaken. Only studies on humans and published in English were considered. Measures of glycemic control and total cholesterol were synthesized for meta-analysis utilizing random-effects models. Of 166 articles retrieved, 15 articles were included for meta-analysis. Patient and graft survival were comparable in a large database study as well as in the only randomized control study. No differences in complications were seen when exocrine drainage was enteric for the systemic venous group. Fasting insulin (-34.13 pmol/mL, p < 0.001) was significantly lower within the portal drained group; however, fasting blood glucose levels (-3.4 mg/dL, p = 0.32) and hemoglobin A1C levels (mean difference 0.124%, p = 0.25) were comparable. Total cholesterol levels (-3.62 mg/dL, p = 0.447), as well as other measures of lipids, showed no difference. Based on this systematic review and meta-analysis, there is no evidence of differences in outcomes or metabolic control in patients undergoing pancreatic transplant with portal venous drainage compared to the systemic venous drainage.

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.

Hepatoselectivity and the evolution of insulin

In spite of major developments in insulin production, purification, pharmaceutical formulation and methods of delivery, problems remain both in the day to day management of insulin-treated diabetes and with regard to its long-term complications. The risks of hypoglycaemia and weight gain are major concerns particularly for the patient, and the persistence of microvascular and premature macrovascular complications as the main causes of morbidity and mortality in both type 1 and type 2 diabetes is a constant reminder that our therapeutic and management strategies are inadequate. One clear and striking difference between currently available insulin treatments and normal physiology is the relative difference in exposure to insulin of the liver versus peripheral tissues. Hepatoselective insulin analogues have the potential to restore the normal hepatic to peripheral gradient in insulin action. Here, we discuss the possible therapeutic potential that such analogues may have over currently available insulin preparations. These benefits could include a lower risk of hypoglycaemia, less weight gain and a potential reduction in microvascular and macrovascular complications. We explore the evolution of insulin with hepatoselectivity in mind and possible strategies to create hepatoselective insulins.

Portal venous versus systemic venous drainage of pancreas grafts: impact on long-term results

Portal venous (PV) and systemic venous (SV) drainage methods are used in pancreas transplantation. The impact of the reconstruction technique on long-term outcome remains unclear. We compared the efficacy and side effects of both methods in 192 recipients who received synchronous pancreas kidney transplants between November 1995 and November 2007. SV and PV drainage were used in 147 and 45 cases, respectively. Pancreas function was determined by hemoglobin A1c levels and annual oral glucose tolerance test. Serum creatinine assessed kidney function. Serum lipid (low-density lipoprotein, high-density lipoprotein and cholesterol) levels and body mass index were measured annually. Patient and graft survival were calculated by log-rank analysis. Pancreas survival for SV versus PV patients was similar after 5 years (81.8% vs. 75.5%) and 10 years (65.1% vs. 60%; p = NS). Similarly, no difference was detected between the groups regarding kidney survival after 5 years (92.9% vs. 84.4%) and 10 years (81.6% vs. 75.5%; p = NS). Patient survival did not differ at 5 years (94.3% vs. 88.8%) and 10 years (85.1% vs. 84.4%; p = NS). Pancreas and kidney function and the lipid profiles were similar in both groups. SV and PV drainage of pancreas grafts offer similar long-term graft survival and function and choice of method should remain the preference of the surgeon.

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.

Pancreas transplantation

Diabetes mellitus is generally treated with oral diabetic drugs and/or insulin. However, the morbidity and mortality associated with this condition increases over time, even in patients receiving intensive insulin treatment, and this is largely attributable to diabetic complications or the insulin therapy itself. Pancreas transplantation in humans was first conducted in 1966, since when there has been much debate regarding the legitimacy of this procedure. Technical refinements and the development of better immunosuppressants and better postoperative care have brought about marked improvements in patient and graft survival and a reduction in postoperative morbidity. Consequently, pancreas transplantation has become the curative treatment modality for diabetes, particularly for type I diabetes. An overview of pancreas transplantation is provided herein, covering the history of pancreas transplantation, indications for transplantation, cadaveric and living donors, surgical techniques, immunosuppressants, and outcome following pancreas transplantation. The impact of successful pancreas transplantation on the complications of diabetes will also be reviewed briefly.

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.

Portal and systemic venous drainage in pancreas and kidney-pancreas transplantation: early surgical complications and outcomes

OBJECTIVE

The objective of this study was to perform a retrospective analysis of the clinical evolution and surgical complications comparing pancreas transplantation with systemic-enteric (SE) drainage versus portal-enteric (PE) drainage.

METHODS

This review of 48 consecutive pancreas transplantation includes 39 simultaneous kidney and pancreas (SKP) and 9 pancreas after kidney (PAK) grafts as well as 2 retransplantations. Venous drainage was systemic (n = 29) or portal (n = 19).

RESULTS

There were no significant differences in patient, kidney, or pancreas allograft survival rates. There were no significant differences in levels of creatinine, fasting glucose, C-peptide, cholesterol, and homeostatic model assessment (HOMA) of beta cells, namely HOMA-s and HOMA-IR index. HbA1c was lower at 6 months and 1 year in the PE group (P < .05). Twenty-two patients displayed early postoperative complications at a mean time of presentation of 12.8 days. All of these patients but 2 needed relaparotomy. The other two were treated either conservatively (1 enteric fistula) or by interventional radiology (arteriovenous fistula). There were 10 graft losses, 5 in each group, due to thrombosis, pancreatitis, and enteric fistulae.

CONCLUSION

Early graft losses were related to pancreatitis and thrombosis. Intermediate-term endocrine function was similar in both groups.

Are there still roles for exocrine bladder drainage and portal venous drainage for pancreatic allografts?

PURPOSE OF REVIEW

Controversy remains regarding the best methodology of handling exocrine pancreatic fluid and pancreatic venous effluent. Bladder drainage has given way to enteric drainage. However, is there an instance in which bladder drainage is preferable? Also, hyperinsulinemia, as a result of systemic venous drainage (SVD), is claimed to be proatherosclerotic, whereas portal venous drainage (PVD) is more physiologic and less atherosclerotic.

RECENT FINDINGS

Bladder drainage remains a viable method of exocrine pancreas drainage, but evidence is sparse that measuring urinary amylase has a substantial benefit in the early detection of acute rejection in all types of pancreas transplants. Currently, there is no incontrovertible evidence that systemic hyperinsulinemia is proatherosclerotic, whereas recent metabolic studies on SVD and PVD showed that there was no benefit to PVD.

SUMMARY

Given the advent of newer immunosuppressive agents and overall lower acute rejection rates, the perceived benefit of bladder drainage as a means to measure urinary amylase as an early marker of rejection has not been substantiated. However, there may be a selective role for bladder drainage in 'high risk' pancreases. Also, without a clear-cut metabolic benefit to PVD over SVD, it remains the surgeon's choice as to which method to use.

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.

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.

Comparison of pancreas-transplanted type 1 diabetic patients with portal-venous versus systemic-venous graft drainage: impact on glucose regulatory hormones and the growth hormone/insulin-like growth factor-I axis

CONTEXT

Pancreas grafts can be drained through the iliac vein (systemic drainage) or the portal vein.

OBJECTIVE

We hypothesized that normalization of portal insulin in patients with portal pancreas graft drainage stimulates the GH/IGF-I axis and thereby contributes to glucose control.

METHODS

We compared patients after combined kidney and pancreas transplantation with portal drainage (n = 7) to patients with systemic drainage of the pancreas graft (n = 8) and nondiabetic controls (n = 8). Overnight fasting sera were analyzed for free and total IGF-I and IGF-binding proteins. Glucose regulatory hormones were examined after an oral glucose tolerance test and GH after stimulation with GHRH.

RESULTS

Systemic drainage led to higher basal and stimulated insulin levels than portal drainage (P < 0.05), but increments in response to oral glucose were reduced in both transplanted groups (P < 0.05 vs. controls). However, glucose tolerance was similar in all groups. Circulating free and total IGF-I and IGF-binding protein-3 were similar to control levels in the systemic drainage group but elevated in the portal drainage group (P < 0.05). Consistently, the GH response was reduced in the portal drainage group (P < 0.05 vs. controls) and correlated inversely with free IGF-I (r = -0.63, P < 0.05).

CONCLUSION

Portal drainage of pancreatic endocrine secretion in pancreas graft recipients raises IGF-I and lowers GH secretion. These changes might explain that glucose regulation is maintained despite lower peripheral insulin levels, compared with patients with systemic graft drainage and nondiabetic control subjects.

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.

Impact of pancreatic venous drainage site on long-term patient and graft outcome in simultaneous pancreas-kidney transplantation

The impact of portal or systemic venous pancreas graft drainage on patient and graft outcome remains controversial. In the present study, the impact of venous drainage type on long-term patient and graft survival is assessed. From July 1996 to December 2002 80 simultaneous pancreas-kidney transplants were enrolled into a prospective study: 44 received a pancreas allograft with portal (P-SPK group) and 36 with systemic venous drainage (S-SPK group). Enteric exocrine drainage was performed in all recipients receiving the same immunosuppressive treatment. At one yr, the patient survival rates were 91.7% and 95.5% both for S-SPK and P-SPK groups, respectively; no significant difference in survival was shown at any time point of the follow-up. The one-, three-, five-, and eight-yr pancreas survival rates were 75%, 60.6%, 56.7%, and 44%, respectively in the S-SPK group compared to 88.6%, 84.1%, 78.4%, and 31.3% in the P-SPK group. The one-, three-, five-, and eight-yr kidney survival rates were 91.7%, 78.15%, 74.1%, and 57.9%, respectively in the S-SPK group compared to 93.2%, 88.6%, 78.4%, and 38.9% in the P-SPK group. Comparing the two groups, no significant difference was shown in the total number of surgical complications as well as in the number of each complication. No significant difference in long-term outcomes between the two groups was shown, even if in S-SPK group a higher incidence of pancreas graft loss has been reported and it was in part correlated to a higher number of graft thromboses.

Donor biopsy and kidney transplant outcomes: an analysis using the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) database

BACKGROUND

Although the degree of glomerulosclerosis on pretransplant donor biopsy is one criterion used in the decision to accept a deceased donor kidney, its relationship with graft survival remains controversial. This study compared graft survival with the degree of glomerulosclerosis found on donor biopsy. We also examined the agreement in degree of glomerulosclerosis between paired kidneys.

METHODS

Biopsy results from 12,129 adult deceased donor transplants between January 1, 2000 and December 31, 2005 were identified in the Organ Procurement and Transplantation Network/United Network for Organ Sharing data, as of September 11, 2006. Of these, 2696 donors had both kidneys biopsied and subsequently transplanted.

RESULTS

Among the groups with greater than 5% glomerulosclerosis, there was no statistically significant difference in graft survival rates (log-rank, P=0.44). The overall graft survival rates of the 0-5% group were significantly superior to those of the >5% groups (1-, 3-, and 5-year rates: 85.9%, 72.4%, and 59.0% for 0-5% group vs. 81.6%, 68.1%, and 53.6% for >5% group, log-rank P<0.001). Agreement between paired kidneys from the same donor was highest for the 0-5% glomerulosclerosis groups (90.6% for pairs with 0-5% glomerulosclerosis in the left kidney vs. 42.5% for pairs with >5% glomerulosclerosis in the left kidney).

CONCLUSION

Donor kidneys with less than 6% glomerulosclerosis were associated with better graft outcomes and intrapair agreement in the degree of glomerulosclerosis. Among kidneys with greater than 5% glomerulosclerosis, the degree of glomerulosclerosis did not help predict graft outcomes. Sampling error may contribute to the lack of outcome differences seen among these kidneys, given the low intrapair agreement.

Pancreas-kidney and pancreas transplantation for the treatment of diabetes mellitus

Kidney transplantation is the treatment of choice for end-stage diabetic nephropathy, but the ultimate treatment today for type 1 diabetes mellitus is the whole vascularized pancreas transplant. Although its use is increasing, pancreas transplantation remains an uncommonly used therapeutic option that normalizes glucose levels and results in stabilization or improvement in secondary complications far better than any other strategy available for treatment of type 1 diabetes. These documented benefits of a simultaneous kidney and pancreas transplant are the basis for its acceptance as an appropriate therapy for patients who have type 1 diabetes mellitus and end-stage renal disease.

Evaluation of vascular complications of pancreas transplantation with high-spatial-resolution contrast-enhanced MR angiography

PURPOSE

To retrospectively evaluate high-spatial-resolution contrast material-enhanced three-dimensional (3D) magnetic resonance (MR) angiography for assessment of vascular complications of pancreas allografts.

MATERIALS AND METHODS

The institutional review board approved the study and waived the requirement for informed patient consent owing to the retrospective nature of the study with use of an anonymous-subject database. The study was HIPAA compliant. The clinical and MR angiography findings in 11 patients (eight men, three women; mean age, 43 years; age range, 30-54 years) who had a history of pancreatic transplant dysfunction and underwent a total of 13 contrast-enhanced 3D MR angiography examinations were retrospectively reviewed. Comparison with conventional angiography findings was possible for four MR angiography examinations, comparison with surgical findings was possible for two examinations, and clinical follow-up was possible for all examinations. Two observers in consensus and blinded to the clinical results performed image analysis of the arterial and venous segments. Classification agreement was assessed with quadratic weighted kappa statistics.

RESULTS

Ten MR angiography examinations revealed vascular complications or signs suggestive of rejection. Only three examinations were considered to have completely normal results. All major complications were detected and included complete or partial arterial graft occlusion, stenosis of the arterial Y-graft caused by a kink, complete venous thrombosis, and arteriovenous fistula with pseudoaneurysm formation. For 46 arterial segments and 15 venous segments with angiographic and/or surgical comparison, overall agreement with MR angiography findings was nearly perfect (mean kappa, 0.983; standard error of the mean, 0.128).

CONCLUSION

High-spatial-resolution MR angiography of pancreas allografts enables assessment of the arterial and venous vascular anatomy and can be used to reliably identify clinically relevant vascular complications.

Metabolic consequences of pancreatic systemic or portal venous drainage in simultaneous pancreas-kidney transplant recipients

AIMS

The aim was to investigate pancreatic B-cell function and insulin sensitivity in simultaneous pancreas-kidney (SPK) recipients with systemic or portal venous drained pancreas allograft using simple and easy tests.

METHODS

The study included 44 patients with Type 1 diabetes and end-stage renal disease who had undergone SPK transplantation: 20 recipients received a pancreas allograft with systemic venous drainage (S-SPK) and 24 with portal venous drainage (P-SPK). We studied only recipients with functioning grafts, with normal serum glucose, HbA(1c) and serum creatinine values, on a stable drug regimen. The subjects were studied at 6, 12, 24, 36, 48 and 60 months after transplantation. Insulin sensitivity and B-cell function indices were derived from blood samples and oral glucose tolerance tests.

RESULTS

All patients from both groups had normal fasting glucose, body mass index and HbA(1c) values by selection. The homeostatic model (HOMA) beta-cell index was significantly lower in P-SPK recipients at several points of the follow-up. HOMA-IR was significantly higher in S-SPK recipients at 6 and 24 months after transplantation and was positively correlated with fasting insulin values, but never exceeded 3.2. There was no significant difference in QUICKI index values between the two groups. Although all patients from both groups always had normal glucose tolerance, the area under the insulin curve was higher in the S-SPK group. Cholesterol, low-density lipoprotein-cholesterol and triglycerides were higher in the P-SPK group.

CONCLUSIONS

The results suggest sustained long-term endocrine function in both groups and show that portal venous drainage does not offer major metabolic advantages.

Bladder vs enteric drainage in simultaneous pancreas-kidney transplantation

BACKGROUND

As a valid therapeutic option for patients with type 1 diabetes mellitus (IDDM) and secondary diabetic nephropathy, simultaneous pancreas-kidney (SPK) transplantation remains more undeveloped than other solid organ transplantations due to restrictions of surgical techniques, especially modes of exocrine pancreatic secretion. Enteric drainage (ED) has recently been increasingly popular due to the long-term complications with bladder drainage (BD). Objectives. Compare results of SPK transplants with enteric vs bladder exocrine drainage since the beginning of our experience with this type of transplantation.

METHODS

From March 1998 to October 2004, 53 SPK transplants were performed, consisting of 30 with bladder drainage (BD) and 23 with enteric drainage (ED). Induction therapy included antilymphocyte globulin (ALG) or anti-CD25 monoclonal antibody. Maintenance regimen consisted of tacrolimus (TAC)/cyclosporine (CsA), mycophenolate mofetil (MMF) and steroids.

RESULTS

Mean age of recipients was 39+/-7 in both groups. No anastomosis leakage occurred in either group. Surgical complications were not significantly different between the two groups. Incidence of acute rejection, major infections and cytomegalovirus disease were also similar. However, the BD group was characterized by a slight increase in number of urologic complications, metabolic acidosis and dehydration. The length of initial hospital stay was likewise comparable. All patients with a functional graft no longer required exogenous insulin. BD actuarial patient survival and graft three-year survival were 96 and 86%, respectively. For ED, the respective results were 97 and 91%, respectively.

CONCLUSION

Compared with BD, perioperative morbidity is not increased by ED, and ED is not associated with increased long-term pancreas graft failure. These data suggest that ED is superior to BD and should be considered as the preferred technique for simultaneous pancreas-kidney transplants.

An evidence-based analysis of simultaneous pancreas-kidney and pancreas transplantation alone

While pancreas transplantation has evolved within two decades from a frustrating and poorly-accepted therapeutic option to a highly successful procedure, the respective benefits of the successive surgical and immunosuppressive developments have remained unclear. The aim of this study was to determine using an evidence-based methodology, which novel approaches have contributed to the current results and whether pancreas transplantation is cost-effective. Out of 2481 articles, 102 analyzed either surgical or immunosuppressive aspects of pancreas transplantation. Urological complications were more frequent in bladder over enteric drainage (range: 62-63% vs. 12-20%, p = 0.0001), but without significant difference in patient or graft survival. Portal drainage was associated with a trend toward fewer complications and better hyperinsulinemia control over systemic drainage in retrospective studies. Immunosuppression combining induction therapy, a calcineurin inhibitor, mycophenolate mophetil (MMF) and corticosteroids were associated with a 40% decreased incidence of rejection (p = 0.01) and an increase in graft survival above 90% at 1 year (p < 0.05). Pancreas transplantation is highly cost-effective compared to conservative alternatives. We conclude that despite a paucity of large studies, enteric drainage should be recommended but the benefits of portal venous drainage remain debated. Quadruple immunosuppression protocols including induction therapy should be the standard regimen.

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.

Outcomes with the selective use of enteric exocrine drainage in pancreas transplantation

BACKGROUND

Bladder drainage of the exocrine secretions of pancreas transplants has been the standard of practice as it affords the ability to monitor for rejection and is thought to be associated with decreased morbidity. Recently, there has been renewed interest in avoiding the urinary tract complications and metabolic derangements that accompany bladder drainage by draining pancreatic exocrine secretions into the jejunum (enteric drainage). We sought to determine whether enteric drainage of pancreas transplants is safe and offers advantages without compromise in graft function or longevity.

METHODS

We retrospectively reviewed all pancreas transplants performed at the University of Washington between 2000 and 2003. Selection of the exocrine drainage method was based on the length of cold ischemia time and whether the pancreas was transplanted alone or in combination with a kidney. Pearson's chi-square and Fisher's Exact tests were used for statistical comparisons in complications or rejections between the groups.

RESULTS

Thirty-four pancreas transplants were performed with exocrine drainage into the bladder used in 17 and enteric drainage in 17. The complication rate was 53% in the bladder-drained group and 41% (P=.49) in the enteric-drained group. The incidence of pancreas rejection was 24% in the bladder-drained versus 29% in the enteric-drained patients (P=.50). One graft failed, which was in the bladder cohort.

CONCLUSIONS

We found comparable rejection and complication rates between groups. We conclude that enteric drainage is safe when used selectively, and entails no increased risks compared with bladder drainage.

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.

Outcome of 118 Pancreas Transplants With Retroperitoneal Portal-Enteric Drainage

BACKGROUND

We have recently described a technique for retroperitoneal pancreas transplantation (RPTx) with portal-enteric drainage (PED). Further experience with 118 RPTx is detailed herein.

METHODS

Between April 2001 and August 2004, 118 patients underwent RPTx with PED among 125 recipients (94.4%) scheduled for this procedure. Surgical complications and patient and graft survivals were recorded prospectively.

RESULTS

After a minimum follow-up period of 3 months (mean 27.8 +/- 13.0 months), 18 recipients (15.2%) required relaparotomy because of bleeding (n = 6; 5.1%), allograft pancreatectomy due to either hyperacute/accelerated rejection (n = 3; 2.5%) or vein thrombosis (n = 3; 2.5%), leak from duodenojejunal anastomosis (n = 2; 1.7%), bleeding and vein thrombectomy (n = 1; 0.8%), or small bowel occlusion due to bezoar (n = 1; 0.8%). One patient had a negative relaparotomy and one underwent two relaparotomies. Most patients with hemorrhage (5/7; 71.4%) were recipients of solitary pancreas grafts managed with heparin infusion. No venous thrombi extended into recipient's superior mesenteric vein. Nonocclusive venous thrombosis was diagnosed with duplex ultrasonography and confirmed at computed tomography in seven patients (5.1%). None of these patients lost graft function. Ten patients (8.5%) were diagnosed with peripancreatic fluid collections, all successfully treated by observation (n = 7) or percutaneous drainage (n = 3). Enteric bleeding occurred in eight recipients (6.8%). Overall, 1-year patient and pancreas survival rates were 97.4% and 92.0%, respectively.

CONCLUSIONS

We conclude that RPTx with PED is a technical option that may be included in the repertoire of pancreas transplant surgeons.

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.

Opções técnicas utilizadas no transplante pancreático em centros brasileiros

OBJETIVO: Analisar o perfil dos principais centros de transplantes do Brasil, quanto às opções técnicas no transplante de pâncreas. MÉTODO: Foi encaminhado um questionário por correio eletrônico (email) para um membro de cada equipe de 12 centros de transplante do Brasil, com casuística mínima de um transplante de pâncreas. O questionário continha 10 perguntas, abordando aspectos controversos e não padronizados. RESULTADOS: A maioria dos centros (90,9%) utiliza incisão mediana. O órgão de escolha a ser implantado primeiro foi principalmente o rim, em 63% dos centros. Em relação à drenagem venosa, 90,9% utilizam a drenagem sistêmica. A ligadura da veia ilíaca interna é realizada em 54,5% dos centros. A maioria dos centros (90,9%) utiliza a drenagem entérica para transplante combinado pâncreas-rim. Para o transplante de pâncreas isolado, apenas cinco centros responderam, sendo que dois utilizam a drenagem entérica e três a vesical. A utilização de dreno na cavidade abdominal ocorre em 63% dos centros. Em 72,7% dos centros é realizada algum tipo de indução na imunossupressão para o transplante combinado pâncreas-rim, sendo a imunossupressão básica a associação de tacrolimus (FK506), micofenolato mofetil (MMF) e corticóide. A antibioticoprofilaxia é realizada por todos os centros e profilaxia para fungos é realizada por seis centros (54,5%). Oito centros (72,7%) utilizam algum tipo de profilaxia para trombose vascular, em esquemas diversos. CONCLUSÃO: Existem diversos caminhos técnicos na condução do transplante pancreático. A falta de padronização dificulta a análise e a comparação dos resultados. Apesar dessa heterogeneidade das equipes, observamos uma tendência para a realização de incisão mediana, drenagem venosa sistêmica e exócrina entérica, com a utilização de algum tipo de profilaxia para trombose vascular nos transplantes combinados pâncreas-rim.

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.

Retroperitoneal pancreas transplantation with portal-enteric drainage

BACKGROUND

Portal-enteric drainage (PED) is the latest refinement in the surgical technique for pancreas transplantation (PTx). We herein describe the results of a modified technique for PED that places the pancreas in a totally retroperitoneal position.

METHODS

Between April 2001 and June 2003, 79 PTx were performed using a retroperitoneal PED technique.

RESULTS

No graft was lost due to surgical complications and the relaparotomy rate was 11.4%. Mean hospital stay averaged 25.9 days (+/-14.4 days) with a 30-day readmission rate of 12.7%. One graft was lost due to delayed (6 months) arterial thrombosis and three to acute rejection. The overall 1-year patient and graft survivals were 98.7% and 93.7%, respectively.

CONCLUSIONS

Our data confirm that PED of pancreas grafts is associated with low morbidity and mortality rates. Whether retroperitoneal graft placement has actual advantages over the "classical" intraperitoneal position remains to be ascertained.

[Pancreatic Transplantation: 2. Surgical technique and post-operative complications]

Since the first pancreatic allograft in 1966, pancreatic transplantations have been performed by numerous surgical teams throughout the world. Initial results were disappointing with a high percentage of technical failures and rejection. Over-optimistic enthusiasm for islet-cell allografts also retarded the development of pancreatic transplantation. Despite this slow start, results of pancreatic transplantation from 1995 onward have been very satisfactory and equivalent to or even better than the results of other solid organ transplants. This success has been due to better graft selection, improved surgical techniques and preservation solutions, and especially to improvements in immunosuppressive protocols. More than 19,000 pancreatic transplantations have now been performed throughout the world including both combined kidney-pancreas transplantations and pancreas-only transplantations. The most satisfactory results occur in the setting of dialysis-dependent renal failure due to diabetes; simultaneous combined kidney and pancreas transplantation is performed with the total pancreas implanted into the bowel and with venous drainage into the portal system. The long-term risks and constraints of chronic diabetes with renal failure must be weighed against the risks of a complex surgical procedure, significant post-operative complications, and the need for long-term immunosuppressive therapy.

Pancreatic transplantation: Beta cell replacement

Diabetes is a leading cause of morbidity and mortality worldwide. Complications of diabetes including renal failure, retinopathy, neuropathy, and cardiovascular disease limit both survival and quality of life. Pancreatic transplantation can restore euglycemia thereby stabilizing or even reversing secondary complications of diabetes as well as improving quality of life particularly in patients with labile diabetes. Recent evidence also shows an improved survival in diabetic patients that undergo pancreatic transplantation when combined with a kidney transplant. Pancreatic transplantation should more properly be referred to as beta cell replacement as the field today encompasses both whole organ and islet cell transplantation. We have outlined herein the indications and contraindications to islet or whole organ pancreas transplantation and we have described periprocedure care and short- and long-term prognosis.

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.

EFFECT OF VENOUS DRAINAGE SITE ON INSULIN ACTION AFTER SIMULTANEOUS PANCREAS-KIDNEY TRANSPLANTATION

BACKGROUND

The aim of the present study was to determine the influence of the venous drainage site on insulin homeostasis in simultaneous pancreas-kidney (SPK) transplant recipients.

METHODS

The study included 12 SPK patients with portal venous drainage (P) and 11 SPK patients with systemic venous drainage (S) of pancreas allograft. All of the participants presented similar characteristics. The euglycemic hyperinsulinemic clamp was performed using a 0.4-mU/kg/min insulin infusion. An infusion of [6,6-(2)H2] glucose was used to determine glucose turnover at the basal state and during the clamp to determine liver and peripheral tissue sensitivity to insulin.

RESULTS

Minor changes in glycemia and insulinemia were shown: fasting plasma glucose was significantly higher in the SPK-P group and insulinemia was higher in the SPK-S group. Hepatic glucose production was similar in both groups. During the clamp, insulin levels were higher in SPK-S recipients, but hepatic glucose production was suppressed in both groups. Glucose use was lower in SPK-S recipients than in SPK-P recipients, 3.32 +/-1.41 mg/kg/min and 4.70 +/-1.64 mg/kg/min, respectively (P<0.02). Basal and under-clamp free fatty acid levels were similar. In addition, no significant difference in cholesterol and low-density lipoprotein levels was shown, whereas high-density lipoprotein levels were higher in the SPK-S group; triglycerides during fasting and under clamp were significantly higher in the SPK-P group.

CONCLUSIONS

In both groups, neither hepatic nor peripheral insulin resistance was detected. In SPK-S recipients, the authors have showed only a lower insulin clearance and a slight decreased peripheral responsiveness to insulin without modifications of lipid status.

Impact of portal venous pancreas graft drainage on kidney graft outcome in simultaneous pancreas-kidney recipients reported to UNOS

Clinical data on the potential immunologic impact of portal (PD) vs. systemic (SD) venous pancreas graft drainage on outcome remains controversial. We reviewed the UNOS database to study the effect of PD vs. SD on the incidence of kidney graft rejection and survival in first cadaveric simultaneous pancreas-kidney (SPK) recipients transplanted 1994-2001. We studied three groups: all SPK (n=6629, 13% PD) (group I), SPK on tacrolimus (n=3563, 17% PD) (group II), and SPK on tacrolimus performed at centers with significant PD experience (n=948, 46% PD) (group III). The cumulative kidney graft rejection incidence for PD vs. SD was only significantly different in group I (for PD vs. SD, respectively: at 6 months, 31% vs. 36% [p=0.015]; at 1 year, 37% vs. 43% [p=0.006]). Kidney graft survival was similar in all groups for PD vs. SD. Multivariate analysis of group III showed only transplantation during the earlier era (1994-96), but not SD, to be an independent risk factor for kidney graft rejection. Portal venous pancreas graft drainage does not affect kidney graft rejection and survival in SPK recipients on tacrolimus. Our data suggests that the efficacy of current immunosuppressive protocols and increasing center experience are clinically much more relevant than any potential immunologic advantage of portal venous drainage in SPK recipients.