Simultaneous pancreas kidney transplants in diabetic patients with end-stage renal disease: the 20-yr experience

Simultaneous Pancreas-Kidney Transplant Outcomes Stratified by Autoantibodies Status and Pretransplant Fasting C-peptide

BACKGROUNDS

Pancreatic beta cell function and islet autoantibodies classically distinguish types of diabetes (type 1 diabetes mellitus [DM] or type 2 DM). Here, we sought to evaluate simultaneous pancreas-kidney (SPK) transplant outcomes stratified by the presence or absence of beta cell function and autoantibodies.

METHODS

SPK recipients were eligible if pretransplant autoantibodies were measured against insulin, islet cell, or glutamic acid decarboxylase 65-kD isoform. Recipients were categorized as A+ or A- based on the detection of ≥1 autoantibodies. Recipients were similarly categorized on the basis of detectable pretransplant fasting C-peptide of ≥2 ng/mL (β+) or <2 ng/mL (β-). Thus, recipients were categorized into 4 groups: A+β-, A-β-, A-β+, and A+β+. Outcomes of interest were overall pancreas graft failure (non-death-censored), death-censored pancreas, or kidney graft failure (death-censored pancreas graft failure [DCGF]; kidney DCGF), composite outcomes with any of the 3 outcomes as pancreas DCGF, use of an antidiabetic agent, or hemoglobin A1c >6.5.

RESULTS

One hundred eighty-three SPK recipients were included: A+β- (n = 72), A-β- (n = 42), A-β+ (n = 49), and A+β+ (n = 20). We did not detect a statistical difference in non-death-censored pancreas graft failure for A+β- recipients compared with other groups: A-β- (adjusted hazard ratio [aHR]: 0.44; 95% confidence interval [CI], 0.14-1.42), A-β+ (aHR: 1.02; 95% CI, 0.37-2.85), and A+β+ (aHR: 0.67; 95% CI, 0.13-3.33) in adjusted analyses. Similar outcomes were observed for other outcomes.

CONCLUSIONS

In SPK recipients, outcomes were similar among recipients with classic features of type 1 DM and various other types of DM.

Analysis of Rejection, Infection and Surgical Outcomes in Type I Versus Type II Diabetic Recipients After Simultaneous Pancreas-Kidney Transplantation

Given the increasing frequency of simultaneous pancreas-kidney transplants performed in recipients with Type II diabetes and CKD, we sought to evaluate possible differences in the rates of allograft rejection, infection, and surgical complications in 298 Type I (T1D) versus 47 Type II (T2D) diabetic recipients of simultaneous pancreas-kidney transplants between 2006-2017. There were no significant differences in patient or graft survival. The risk of biopsy-proven rejection of both grafts was not significantly different between T2D and T1D recipients (HRpancreas = 1.04, p = 0.93; HRkidney = 0.96; p = 0.93). Rejection-free survival in both grafts were also not different between the two diabetes types (ppancreas = 0.57; pkidney = 0.41). T2D had a significantly lower incidence of de novo DSA at 1 year (21% vs. 39%, p = 0.02). There was no difference in T2D vs. T1D recipients regarding readmissions (HR = 0.77, p = 0.25), infections (HR = 0.77, p = 0.18), major surgical complications (HR = 0.89, p = 0.79) and thrombosis (HR = 0.92, p = 0.90). In conclusion, rejection, infections, and surgical complications after simultaneous pancreas-kidney transplant are not statistically significantly different in T2D compared to T1D recipients.

Multi-Centre UK Analysis of Simultaneous Pancreas and Kidney (SPK) Transplant in Recipients With Type 2 Diabetes Mellitus

90% of the UK diabetic population are classified as T2DM. This study aims to compare outcomes after SPK transplant between recipients with T1DM or T2DM. Data on all UK SPK transplants from 2003-2019 were obtained from the NHSBT Registry (n = 2,236). Current SPK transplant selection criteria for T2DM requires insulin treatment and recipient BMI < 30 kg/m2. After exclusions (re-transplants/ambiguous type of diabetes) we had a cohort of n = 2,154. Graft (GS) and patient (PS) survival analyses were conducted using Kaplan-Meier plots and Cox-regression models. Complications were compared using chi-squared analyses. 95.6% of SPK transplants were performed in recipients with T1DM (n = 2,060). Univariate analysis showed comparable outcomes for pancreas GS at 1 year (p = 0.120), 3 years (p = 0.237), and 10 years (p = 0.196) and kidney GS at 1 year (p = 0.438), 3 years (p = 0.548), and 10 years (p = 0.947). PS was comparable at 1 year (p = 0.886) and 3 years (p = 0.237) and at 10 years (p = 0.161). Multi-variate analysis showed comparable outcomes in pancreas GS (p = 0.564, HR 1.221, 95% CI 0.619, 2.406) and PS(p = 0.556, HR 1.280, 95% CI 0.563, 2.911). Comparable rates of common complications were demonstrated. This is the largest series outside of the US evaluating outcomes after SPK transplants and shows similar outcomes between T1DM and T2DM recipients. It is hoped dissemination of this data will lead to increased referral rates and assessment of T2DM patients who could benefit from SPK transplantation.

Stem Cell-Derived Islet Transplantation in Patients With Type 2 Diabetes: Can Diabetes Subtypes Guide Implementation?

Historically, only patients with brittle diabetes or severe recurrent hypoglycemia have been considered for islet transplantation (ITx). This population has been selected to optimize the risk-benefit profile, considering risks of long-term immunosuppression and limited organ supply. However, with the advent of stem cell (SC)-derived ITx and the potential for immunosuppression-free ITx, consideration of a broader recipient cohort may soon be justified. Simultaneously, the classical categorization of diabetes is being challenged by growing evidence in support of a clustering of disease subtypes that can be better categorized by the All New Diabetics in Scania (ANDIS) classification system. Using the ANDIS classification, 5 subtypes of diabetes have been described, each with unique causes and consequences. We evaluate consideration for ITx in the context of this broader patient population and the new classification of diabetes subtypes. In this review, we evaluate considerations for ITx based on novel diabetes subtypes, including their limitations, and we elaborate on unique transplant features that should now be considered to enable ITx in these "unconventional" patient cohorts. Based on evidence from those receiving whole pancreas transplant and our more than 20-year experience with ITx, we offer recommendations and potential research avenues to justify implementation of SC-derived ITx in broader populations of patients with all types of diabetes.

Higher Fasting Pretransplant C-peptide Levels in Type 2 Diabetics Undergoing Simultaneous Pancreas-kidney Transplantation Are Associated With Posttransplant Pancreatic Graft Dysfunction

BACKGROUND

Among selected patients with type 2 diabetes mellitus (T2DM), simultaneous pancreas and kidney (SPK) transplants can be an effective option. However, data are limited about outcomes in T2DM SPK recipients based on the pretransplant C-peptide levels.

METHODS

In this study, we reviewed all T2DM SPK recipients and categorized them based on the pretransplant fasting C-peptide levels into 3 groups: low (≤2 ng/mL), medium (>2-8 ng/mL), and high (>8 ng/mL). Several measures of graft failures (GFs), graft dysfunction, and composite outcomes were of interest.

RESULTS

There were a total of 76 SPK recipients (low, n = 14; medium, n = 47; high, n = 15). At the last follow-up, the low group did not reach any outcome; in contrast, 11 (23%) in the medium group and 5 (33%) in the high group reached the uncensored composite outcome; 6 (13%) in the medium group and 2 (13%) in the high group had GF; and 8 (17%) in the medium group and 4 (26.7%) in the high group reached the death-censored composite outcomes. In a fully adjusted model, each pretransplant C-peptide unit was not associated with an increased risk of the composite outcome, GF, or death-censored composite outcomes. However, in multivariate analysis with limited adjustment, pretransplant C-peptide was associated with the composite outcome (hazard ratio: 1.18, 95% confidence interval, 1.01-1.38; P = 0.03) and death-censored composite outcome (hazard ratio: 1.20; 95% confidence interval, 1.01-1.42; P = 0.03).

CONCLUSIONS

Although limited by the small sample size, we found excellent outcomes among T2DM SPK recipients overall. However, higher levels of pretransplant C-peptide may be associated with inferior posttransplant outcomes that include graft dysfunction.

Modern indications for referral for kidney and pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation (PTx) is currently the only therapy that can predictably achieve sustained euglycemia independent of exogenous insulin administration in patients with insulin-dependent diabetes mellitus. This procedure involves a complex abdominal operation and lifetime dependence on immunosuppressive medications. Therefore, PTx is most frequently performed in combination with other organs, usually a kidney transplant for end stage diabetic nephropathy. Less frequently, solitary PTx may be indicated in patients with potentially life-threatening complications of diabetes mellitus. There remains confusion and misperceptions regarding indications and timing of patient referral for PTx.

RECENT FINDINGS

In this review, the referral, evaluation, and listing process for PTx is described, including a detailed discussion of candidate assessment, indications, contraindications, and outcomes.

SUMMARY

Because the progression of diabetic kidney disease may be less predictable than other forms of kidney failure, early referral for planning of renal and/or pancreas transplantation is paramount to optimize patient care and allow for possible preemptive transplantation.

Pancreas Transplantation in Minorities including Patients with a Type 2 Diabetes Phenotype

Background: Prior to year 2000, the majority of pancreas transplants (PTx) were performed as simultaneous pancreas-kidney transplants (SPKTs) in Caucasian adults with end stage renal failure secondary to type 1 diabetes mellitus (T1DM) who were middle-aged. In the new millennium, improving outcomes have led to expanded recipient selection that includes patients with a type 2 diabetes mellitus (T2DM) phenotype, which excessively affects minority populations. Methods: Using PubMed® to identify appropriate citations, we performed a literature review of PTx in minorities and in patients with a T2DM phenotype. Results: Mid-term outcomes with SPKT in patients with uremia and circulating C-peptide levels (T2DMphenotype) are comparable to those patients with T1DM although there may exist a selection bias in the former group. Excellent outcomes with SPKT suggests that the pathophysiology of T2DM is heterogeneous with elements consisting of both insulin deficiency and resistance related to beta-cell failure. As a result, increasing endogenous insulin (Cp) production following PTx may lead to freedom checking blood sugars or taking insulin, better metabolic counter-regulation, and improvements in quality of life and life expectancy compared to other available treatment options. Experience with solitary PTx for T2DM or in minorities is limited but largely mirrors the trends reported in SPKT. Conclusions: PTx is a viable treatment option in patients with pancreas endocrine failure who are selected appropriately regardless of diabetes type or recipient race. This review will summarize data that unconventional patient populations with insulin-requiring diabetes may gain value from PTx with an emphasis on contemporary experiences and appropriate selection in minorities in the new millennium.

Pancreas Transplantation for Type 2 Diabetes: A Systematic Review, Critical Gaps in the Literature, and a Path Forward

Pancreas transplantation in patients with type 2 diabetes (T2D) remains relatively uncommon compared with pancreas transplantation in patients with type 1 diabetes (T1D); however, several studies have suggested similar outcomes between T2D and T1D, and the practice has become increasingly common. Despite this growing interest in pancreas transplantation in T2D, no study has systematically summarized the data to date. We systematically reviewed the literature on pancreas transplantation in T2D patients including patient and graft survival, glycemic control outcomes, and comparisons with outcomes in T2D kidney transplant alone and T1D pancreas transplant recipients. We searched biomedical databases from January 1, 2000, to January 14, 2021, and screened 3314 records, of which 22 full texts and 17 published abstracts met inclusion criteria. Full-text studies were predominantly single center (73%), whereas the remaining most often studied the Organ Procurement and Transplantation Network database. Methodological quality was mixed with frequent concern for selection bias and concern for inconsistent definitions of both T2D and pancreas graft survival across studies. Overall, studies generally reported favorable patient survival, graft survival, and glycemic control outcomes for pancreas transplantation in T2D and expressed a need to better characterize the T2D patients who would benefit most from pancreas transplantation. We suggest guidance for future studies, with the aim of supporting the safe and evidence-based treatment of end-stage T2D and judicious use of scarce resources.

Inferior survival outcomes of pancreas transplant alone in uremic patients

Theoretically, pancreas transplant alone in uremic (PTAU) patients could also be one of the options for those waiting for both pancreas and kidney grafts, but it has never been reported. There were 160 cases of pancreas transplant in this study, including 16% PTAU. The 5-year patient survival was 66.2% after PTAU, 94.5% after SPK, 95.8% after PAK, and 95.4% after PTA. Rejection of pancreas graft was significantly lower in PTAU group (3.8%), followed by 16.7% in pancreas after kidney transplant (PAK), 29.8% in simultaneous pancreas and kidney transplant (SPK) and 37.0% in pancreas transplant alone (PTA). Fasting blood sugar and serum HbA1c levels after PTAU were not significantly different from those by other subgroups. The 5-year death-censored pancreas graft survival was 100% after PTAU and PAK, and 97.0% after SPK and 77.9% after PTA. However, the 5-year death-uncensored pancreas graft survival was 67.0% after PTAU, 100% after PAK, 91.3% after SPK, and 74.0% after PTA. The superior graft survival in the PTAU group was achieved only if deaths with a functioning graft were censored. In conclusion, given the inferior patient survival outcome, PTAU is still not recommended unless SPK and PAK is not available. Although PTAU could be a treatment option for patients with diabetes complicated by end-stage renal disease (ESRD) in terms of surgical risks, endocrine function, and immunological and graft survival outcomes, modification of the organ allocation policies to prioritize SPK transplant in eligible patients should be the prime goal.

Do pretransplant C-peptide levels predict outcomes following simultaneous pancreas-kidney transplantation? A matched case-control study

Following simultaneous pancreas-kidney transplantation (SPKT), survival outcomes are reported as equivalent in patients with detectable pretransplant C-peptide levels (Cp+) and a "type 2″ diabetes mellitus (DM) phenotype compared to type 1 (Cp negative [Cp-]) DM. We retrospectively compared 46 Cp+ patients pretransplant (≥2.0 ng/mL, mean 5.4 ng/mL) to 46 Cp- (level < 0.5 ng/mL) case controls matched for recipient age, gender, race, and transplant date. Early outcomes were comparable. Actual 5-year patient survival (91% versus 94%), kidney graft survival (69% versus 86%, p = .15), and pancreas graft survival (60% versus 86%, p = .03) rates were lower in Cp+ versus Cp- patients, respectively. The Cp+ group had more pancreas graft failures due to insulin resistance (13% Cp+ versus 0% Cp-, p = .026) or rejection (17% Cp+ versus 6.5% Cp-, p = .2). Post-transplant weight gain > 5 kg occurred in 72% of Cp+ versus 26% of Cp- patients (p = .0001). In patients with functioning grafts, mean one-year post-transplant HbA1c levels (5.0 Cp+ versus 5.2% Cp-) were comparable, whereas Cp levels were higher in Cp+ patients (5.0 Cp+ versus 2.6 ng/mL Cp-). In this matched case-control study, outcomes were inferior in Cp+ compared to Cp- patients following SPKT, with post-transplant weight gain, insulin resistance, and rejection as potential mitigating factors.

Pancreas transplantation perceptions and practice: Results from a national US survey

BACKGROUND

Due to a substantial decline in pancreas transplantation (PT) across the United States over the past 15 years, we sought to understand the perceptions and practices of US PT programs.

METHODS

Surveys were sent to members of the American Society of Transplantation Surgeons and the American Society of Transplantation by email and professional society postings between August 2019 and November 2019.

RESULTS

One hundred twenty three responses were recorded from 56 unique programs. Program characteristics were obtained from the Scientific Registry of Transplant Recipients. Respondents were transplant surgeons (71%), transplant nephrologists (17%), trainees (9%), and allied professionals (3%). Programs were defined according to annual volume as: low (<5 PT/year), intermediate (6-20), or high (>20). High-volume programs reported that these factors were most important for increased PT: expansion of recipient selection, more aggressive donor utilization, and hiring of PT program-specific personnel. At both the program and national level, the vast majority (82% and 79%, respectively) felt the number of PTs currently performed are not in balance with patients' needs.

CONCLUSIONS

Overall, programs reported that the option of PT is not offered adequately to diabetic patients and that strategies to maintain higher PT volume are most evident at intermediate, and especially, high-volume programs.

A comparative study of pancreas transplantation between type 1 and 2 diabetes mellitus

Background

Pancreas transplantation remains the best long-term treatment option to achieve physiological euglycemia and insulin independence in patients with labile diabetes mellitus (DM). It is widely accepted as an optimal procedure for type 1 DM (T1DM), but its application in type 2 DM (T2DM) is not unanimously acknowledged.

Methods

In total, 146 diabetes patients undergoing pancreas transplantation were included in this study. Clinical data and outcomes were compared between the T1DM and T2DM groups.

Results

Majority (93%) of the pancreas transplantations in T2DM were for uremic recipients. Complications occurred in 106 (73%) patients, including 70 (48%) with early complications before discharge and 79 (54%) with late complications during follow-up period. Overall, rejection of pancreas graft occurred in 37 (25%) patients. Total rejection rate in T2DM recipients was significantly lower than that in T1DM. The short- and long-term outcomes for endocrine function in terms of fasting blood sugar and hemoglobin A1c levels and graft survival rates are comparable between the T2DM and T1DM groups.

Conclusions

T2DM is not inferior to T1DM after pancreas transplantation in terms of surgical risks, immunological and endocrine outcomes, and graft survival rates. Therefore, pancreas transplantation could be an effective option to treat selected uremic T2DM patients without significant insulin resistance.

Single center results of simultaneous pancreas-kidney transplantation in patients with type 2 diabetes

Studies have found similar outcomes of Simultaneous Pancreas-Kidney transplantation (SPKT) in patients with Type 2 (T2D) and Type 1 diabetes (T1D). However, there are scarce data evaluating the association of recipient factors such as age, BMI, or pretransplant insulin requirements with outcomes, thus the criteria for the optimal recipient selection remains unclear. In this study, 284 T1D and 39 T2D patients, who underwent SPKT between 2006 and 2017 with 1 year of follow-up at minimum, were assessed for potential relationship of pretransplant BMI and insulin requirements with posttransplant diabetes and pancreatic graft failure. Kaplan-Meier analysis showed similar rates of freedom from posttransplant diabetes (94.7% T2D vs. 92.3% T1D at 1 yr, and 88.1% T2D vs. 81.1% T1D at 5 yrs) and graft survival (89.7% T2D vs. 90.4% T1D at 1 yr, and 89.7% T2D vs. 81.2% T1D at 5 yrs). There was no significant association between BMI or pretransplant insulin requirements with posttransplant diabetes occurrence in either T1D (p = .10, .43, respectively) or T2D (p = .12, .63) patients in the cohort; or with graft failure (T1D: p = .40, .09; T2D: p = .71, .28). These observations suggest a less restricted approach to selective use of SPKT in patients with T2D.

Impact of Early Pancreatic Graft Loss on Outcome after Simultaneous Pancreas-Kidney Transplantation (SPKT)-A Landmark Analysis

(1) Background: Simultaneous pancreas-kidney transplantation (SPKT) is a standard therapeutic option for patients with diabetes mellitus type I and kidney failure. Early pancreas allograft failure is a complication potentially associated with worse outcomes. (2) Methods: We performed a landmark analysis to assess the impact of early pancreas graft loss within 3 months on mortality and kidney graft survival over 10 years. This retrospective single-center study included 114 adult patients who underwent an SPKT between 2005 and 2018. (3) Results: Pancreas graft survival rate was 85.1% at 3 months. The main causes of early pancreas graft loss were thrombosis (6.1%), necrosis (2.6%), and pancreatitis (2.6%). Early pancreas graft loss was not associated with reduced patient survival (p = 0.168) or major adverse cerebral or cardiovascular events over 10 years (p = 0.741) compared to patients with functioning pancreas, after 3 months. Moreover, kidney graft function (p = 0.494) and survival (p = 0.461) were not significantly influenced by early pancreas graft loss. (4) Conclusion: In this study, using the landmark analysis technique, early pancreas graft loss within 3 months did not significantly impact patient or kidney graft survival over 10 years.

Simultaneous pancreas and kidney transplantation for end-stage kidney disease patients with type 2 diabetes mellitus: a systematic review and meta-analysis

PURPOSE

The indications for patients with type 2 diabetes mellitus (T2DM) combined with end-stage kidney disease (ESKD) undertaking simultaneous pancreas and kidney transplantation (SPK) remain an unresolved issue. This study aimed to systematically review the survival outcomes of SPK among T2DM-ESKD patients.

METHODS

Online databases including PubMed, MEDLINE, EMBASE, and the CENTRAL Library, CNKI, Chinese Biomedical Literature Database, and Wan-Fang database were used to locate the studies of ESKD patients with T2DM undertaking SPK up to May 2021. A third reviewer was consulted if there were disagreements. Data were analyzed with STATA (15.0).

RESULTS

Nine cohort studies were identified. The pooled 1-year, 3-year, and 5-year patient survival rates of patients with T2DM and ESKD after SPK were 98%, 95%, and 91% respectively. Comparing the treatment effect of SPK between type 1 diabetes mellitus (T1DM) and T2DM, the survival estimates were comparable. For T2DM patients, SPK had a survival advantage compared with KTA.

CONCLUSIONS

The synthesized clinical outcomes of T2DM patients with ESKD after SPK were relatively better than KTA, but a subset of T2DM-ESKD patients who would benefit the most from SPK was to be defined. PROSPERO registration number CRD42019118321. Date of registration: 14 Jan 2019 (retrospectively registered).

Results from an International Survey of Donor and Recipient Eligibility for Solid Organ Pancreas Transplantation

Background

Current solid organ pancreas transplantation protocols have differing donor criteria for donor pancreas acceptance and recipient eligibility criteria for transplant workup. We quantified this variation and compared current Australia and New Zealand (ANZ) solid pancreas transplant eligibility criteria with current international practice.

Material/Methods

A survey of donor and recipient eligibility criteria for solid pancreas transplantation was disseminated to 85 transplant units in 23 countries. Responses were grouped by regions (ANZ, North America, Eurotransplant, Europe, United Kingdom) and analyzed for significant differences between regions and for ANZ compared to all other regions.

Results

Responding UK pancreas transplant units reported the highest mean donor upper age limit (61 years old) and the highest mean donation after cardiac death donor (DCD) age limit (55 years old). All responding UK and USA units utilized DCD pancreas donors and accepted suitable type 2 diabetes (T2DM) recipients for pancreas transplantation; however, this was less common among responding European or Eurotransplant units. ANZ mean standard and DCD pancreas donor upper age limits (47 and 35 years old, respectively) were lower compared to all other regions (54 years old and 48 years old, respectively).

Conclusions

Pancreas donor age limits, DCD pancreas donor utilization, and transplanting T2DM recipients differ between responding pancreas transplant units. ANZ units have more conservative donor upper age limits compared to other responding units. Increased utilization of DCD pancreas donors and T2DM recipients while standardizing pancreas donor age limits might increase donor numbers and improve access to solid pancreas transplantation both locally and abroad.

Metabolic outcomes and renal function after simultaneous kidney/pancreas transplantation compared with kidney transplantation alone for type 2 diabetes mellitus patients

In this study, we aimed to compare the metabolic outcomes, renal function, and survival outcomes of simultaneous pancreas and kidney transplantation (SPK) and kidney transplantation alone (KTA) among end‐stage kidney disease (ESKD) patients with type II diabetes mellitus (T2DM). Patients with ESKD and T2DM who underwent KTA (n = 85) or SPK (n = 71) in a transplant center were retrospectively reviewed. Metabolic profiles, renal function, and survival outcomes were assessed repeatedly at different follow‐up time points. Propensity score procedures were applied to enhance between‐group comparability. The levels of renal and metabolic outcomes between SPK and KTA over time were examined and analyzed using mixed‐model repeated‐measures approaches. The median follow‐up period was 1.8 years. Compared with KTA, SPK resulted in superior metabolic outcomes and renal function, with lower levels of glycated hemoglobin (HbA1c; P = 0.0055), fasting blood glucose (P < 0.001), triglyceride (P = 0.015), cholesterol (P = 0.0134), low‐density lipoprotein (P = 0.0161), and higher estimated glomerular filtration rate (eGFR; P < 0.001). SPK provided better metabolic outcomes and renal function. The survival outcomes of the recipients and grafts were comparable between the two groups.

Single center results of simultaneous pancreas-kidney transplantation in patients with type 2 diabetes

Studies have found similar outcomes of Simultaneous Pancreas-Kidney transplantation (SPKT) in patients with Type 2 (T2D) and Type 1 diabetes (T1D). However, there are scarce data evaluating the association of recipient factors such as age, BMI, or pretransplant insulin requirements with outcomes, thus the criteria for the optimal recipient selection remains unclear. In this study, 284 T1D and 39 T2D patients, who underwent SPKT between 2006 and 2017 with 1 year of follow-up at minimum, were assessed for potential relationship of pretransplant BMI and insulin requirements with posttransplant diabetes and pancreatic graft failure. Kaplan-Meier analysis showed similar rates of freedom from posttransplant diabetes (94.7% T2D vs. 92.3% T1D at 1 yr, and 88.1% T2D vs. 81.1% T1D at 5 yrs) and graft survival (89.7% T2D vs. 90.4% T1D at 1 yr, and 89.7% T2D vs. 81.2% T1D at 5 yrs). There was no significant association between BMI or pretransplant insulin requirements with posttransplant diabetes occurrence in either T1D (p = .10, .43, respectively) or T2D (p = .12, .63) patients in the cohort; or with graft failure (T1D: p = .40, .09; T2D: p = .71, .28). These observations suggest a less restricted approach to selective use of SPKT in patients with T2D.

The homolateral simultaneous pancreas-kidney transplantation: a single-center experience in China

Background

To preliminarily explore the clinical effect of the homolateral simultaneous pancreas and kidney (SPK) transplantation in China.

Methods

SPK using the surgical technique was performed in 88 patients from September 2016 to July 2019 in the Department of Transplantation of the Second Affiliated Hospital of Guangzhou Medical University. Patients were followed up for 2 to 36 months to summarize the efficacy and complications.

Results

Up to now, 83 patients have achieved good clinical efficacy with no major surgical complications, but 3 patients died of severe infection and 2 have graft loss. The serum creatinine (Scr) at 1, 3, 6, 12, 24 months after operation were 118, 119, 116, 114, 110 umol/L; fasting blood glucose were 5.8, 5.0, 5.0, 4.9, 4.8 mmol/L; and glycated hemoglobin at 3, 6, 12, 24 months after transplantation were 5.2%, 5.5%, 5.2%, 5.1%. One- and 2-year patient, pancreas, and kidney graft survival rates were 96.1%, 93.8%, 95.0% and 96.1%, 93.8%, 95.0%. Main complications included 20 cases of kidney rejection (22.7%), 22 cases of pancreas rejection (25.0%), 31 cases of pulmonary infection (35.2%), 28 cases of gastrointestinal bleeding (31.8%), 2 cases of splenic vein thrombosis (2.3%), 2 case of artery thrombosis and anastomotic leak (2.3%) and 2 cases of pancreas allograft dysfunction (2.3%).

Conclusions

homolateral simultaneous pancreas-kidney transplantation has a definite therapeutic effect. The relatively simple surgical method can be done with a smaller wound in unilateral fossa iliaca.

Reappraisal of pancreas transplantation

Pancreas transplantation is currently the most effective and curative treatment for complicated type 1 diabetes mellitus, providing durable and physiological insulin-independent euglycemia, preventing worsening or ameliorating of diabetic complications, and improving quality of life. Currently, more than 31 000 pancreas transplantation procedures have been performed, mainly in the United States. Pancreas transplantation is still an uncommon procedure in Asia, mainly performed in Korea, Taiwan, and Japan. The first pancreas (simultaneous pancreas and kidney transplantation) transplantation was successfully initiated at Taipei Veterans General Hospital on September 19, 2003, and we are the first team to be qualified to perform human pancreas procurement and transplantation by Taiwan Department of Health on August 31, 2007. The technique success rate in our pancreas transplantation is 97%, with 1-year pancreas graft survival rate of 95.8%, 5-year pancreas graft survival rate of 89.9%, and 10-year pancreas graft survival rate of 65.9%.

Pancreas transplantation in type 2 diabetes: expanding the criteria

PURPOSE OF REVIEW

Pancreas transplantation in type 2 diabetes mellitus (T2DM) candidates remains disproportionately lower than in type 1 diabetes mellitus (T1DM); however, outcomes in carefully selected patients mirrors that of T1DM. Despite the 2014 United Network for Organ Sharing (UNOS) eligibility criteria for simultaneous pancreas/kidney transplant (SPK) transplantation in T2DM patients, an expected increase in the number of transplants was not observed.

RECENT FINDINGS

In an updated International Pancreas and Transplant Registry (IPTR) analysis, 1514 primary deceased donor pancreas transplants were performed in T2DM recipients [1995-2015, SPK 88%, pancreas after kidney (PAK) 9%, pancreas transplant alone (PTA) 3%]. In contrast to the declining number of SPK transplants for T1DM, the number of primary SPK transplants in T2DM patients is increasing over time in the USA. Improvement over time was noted for T2DM SPK patient and graft survival, and the rate of technical failures decreased, paralleling similar overall trends for pancreas transplants in general. Long-term follow-up data of pancreas outcomes in C-peptide positive vs. negative demonstrate noninferior outcomes. BMI does not appear to impact outcomes in carefully selected T2DM candidates.

SUMMARY

The current UNOS regulations that currently limit access of T2DM to pancreas transplantation based on strict BMI criteria and C-peptide levels need to be liberated.

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.

β Cell Replacement Therapy: The Next 10 Years

β cell replacement with either pancreas or islet transplantation has progressed immensely over the last decades with current 1- and 5-year insulin independence rates of approximately 85% and 50%, respectively. Recent advances are largely attributed to improvements in immunosuppressive regimen, donor selection, and surgical technique. However, both strategies are compromised by a scarce donor source. Xenotransplantation offers a potential solution by providing a theoretically unlimited supply of islets, but clinical application has been limited by concerns for a potent immune response against xenogeneic tissue. β cell clusters derived from embryonic or induced pluripotent stem cells represent another promising unlimited source of insulin producing cells, but clinical application is pending further advances in the function of the β cell like clusters. Exciting developments and rapid progress in all areas of β cell replacement prompted a lively debate by members of the young investigator committee of the International Pancreas and Islet Transplant Association at the 15th International Pancreas and Islet Transplant Association Congress in Melbourne and at the 26th international congress of The Transplant Society in Hong Kong. This international group of young investigators debated which modality of β cell replacement would predominate the landscape in 10 years, and their arguments are summarized here.

Pancreas transplantation in unconventional recipients

PURPOSE OF REVIEW

Advances in surgical technique and immunosuppression have significantly improved outcomes after pancreas transplantation, and as a result pancreas transplants increasingly are being performed for indications other than type 1 diabetes mellitus. This review summarizes the current literature on pancreas transplantation in unconventional recipient populations.

RECENT FINDINGS

An increasing body of work suggests that pancreas transplantation can be performed with good outcomes in patients with type 2 diabetes mellitus and those 50 years of age and older. Obesity appears detrimental to patient and pancreas graft survival, and bariatric surgery prior to transplantation may be of increasing interest and relevance. There are limited data yielding mixed outcomes on pancreas transplantation in patients with HIV or hepatitis C virus. However, rapidly improving antiviral therapies are prolonging survival in patients with HIV and chronic hepatitis C virus infections and may increase the number of candidates available for pancreas transplantation in these populations in the future.

SUMMARY

Despite limited literature in these patient populations, pancreas transplantation may be a viable treatment option for endocrine pancreas failure in appropriately selected patients regardless of disease cause or age.

Long-term Metabolic Outcomes of Functioning Pancreas Transplants in Type 2 Diabetic Recipients

BACKGROUND

Limited data are available regarding the long-term metabolic outcomes of functioning pancreas transplants in patients with type 2 diabetes mellitus (T2DM).

METHODS

To compare the long-term effects of pancreas transplantation in terms of insulin resistance and β cell function, comparison of metabolic variables was performed between type 1 diabetes mellitus (T1DM) and T2DM patients from 1-month posttransplant to 5 years using generalized, linear-mixed models for repeated measures.

RESULTS

Among 217 consecutive patients who underwent pancreas transplantation at our center between August 2004 and January 2015, 193 patients (151 T1DM and 42 T2DM) were included in this study. Throughout the follow-up period, postoperative hemoglobin A1c did not differ significantly between T1DM and T2DM patients, and the levels were constantly below 6% (42 mmol/mol) until 5 years posttransplant, whereas C-peptide was significantly higher in T2DM (P = 0.014). There was no difference in fasting insulin, homeostasis model assessment (HOMA) of insulin resistance, HOMA β cell, or the insulinogenic index between the groups. Furthermore, fasting insulin and HOMA-insulin resistance steadily decreased in both groups during the follow-up period.

CONCLUSIONS

There was no significant difference in the insulin resistance or β-cell function after pancreas transplantation between T1DM and T2DM patients. We demonstrated that pancreas transplantation is capable of sustaining favorable endocrine functions for more than 5 years in T2DM recipients.

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.

Kidney Transplantation in the Diabetic Patient

Diabetes mellitus is one of the most important causes of chronic kidney disease (CKD). In patients with advanced diabetic kidney disease, kidney transplantation (KT) with or without a pancreas transplant is the treatment of choice. We aimed to review current data regarding kidney and pancreas transplant options in patients with both type 1 and 2 diabetes and the outcomes of different treatment modalities. In general, pancreas transplantation is associated with long-term survival advantages despite an increased short-term morbidity and mortality risk. This applies to simultaneous pancreas kidney transplantation or pancreas after KT compared to KT alone (either living donor or deceased). Other factors as living donor availability, comorbidities, and expected waiting time have to be considered whens electing one transplant modality, rather than a clear benefit in survival of one strategy vs. others. In selected type 2 diabetic patients, data support cautious utilization of simultaneous pancreas kidney transplantation when a living kidney donor is not an option. Pancreas and kidney transplantation seems to be the treatment of choice for most type 1 diabetic and selected type 2 diabetic patients.

Simultaneous pancreas and kidney transplantation: current trends and future directions

Purpose of review

Important trends are being observed in pancreas transplantation in the USA. We will describe recent trends in simultaneous pancreas kidney (SPK) transplantation related to immunosuppression, treatment of rejection, and transplantation for patients of advanced age and C-peptide positive diabetes.

Recent findings

Rates of pancreas transplantation have declined, despite improved pancreatic graft outcomes. Regarding immunosuppression, trends in SPK transplantation include T-cell depletion induction therapy, waning mammalian target of rapamycin inhibitor use and steroid use in greater than 50% of pancreas transplant recipients with few patients undergoing late steroid weaning. Rejection of the pancreas may be discordant with the kidney after SPK and there is a greater appreciation of antibody-mediated rejection of the pancreas allograft. De-novo donor-specific antibody without graft dysfunction remains an active area of study, and the treatment for this condition is unclear. SPKs are being performed with greater frequency in type 2 diabetes mellitus patients and in patients of advanced age, with exemplary results.

Summary

The current state of the art in SPK transplantation is yielding superb and improving results.

Pancreas transplantation in C-peptide positive patients: does "type" of diabetes really matter?

BACKGROUND

In the past, type 2 (C-peptide positive) diabetes mellitus (DM) was a contraindication for simultaneous pancreas-kidney transplantation (SPKT).

STUDY DESIGN

We retrospectively analyzed outcomes in SPKT recipients according to pretransplantation C-peptide levels ≥ 2.0 ng/mL or < 2.0 ng/mL.

RESULTS

From November 2001 to March 2013, we performed 162 SPKTs including 30 (18.5%) in patients with C-peptide levels ≥ 2.0 ng/mL pretransplantation (C-peptide positive group, range 2.1 to 12.4 ng/mL) and 132 in patients with absent or low C-peptide levels (<2.0 ng/mL, C-peptide "negative"). C-peptide positive patients were older at SPKT, had a later age of onset and shorter duration of pretransplantation DM, and more were African-American (all p < 0.05) compared with C-peptide negative patients. With a mean follow-up of 5.6 years, patient (80% vs 82.6%), kidney graft (63.3% vs 68.9%), and pancreas graft survivals (50% vs 62.1%, all p = NS) rates were comparable in C-peptide positive and negative patients, respectively. At latest follow-up, there were no differences in acute rejection episodes, surgical complications, major infections, readmissions, hemoglobin A1c levels, serum creatinine, and estimated glomerular filtration rate levels between the 2 groups. C-peptide levels were higher (mean 5.0 vs 2.6 ng/mL, p < 0.05) and post-transplant weight gain (≥ 5 kg) was more common (57% vs 33%, p = 0.004) in the C-peptide positive group. Survival outcomes in C-peptide positive (n = 14) vs C-peptide negative (n = 22) African-American patients were similar, as were outcomes in C-peptide positive patients with a body mass index < or ≥ 28 kg/m(2).

CONCLUSIONS

Patients with higher pretransplantion C-peptide levels appear to have a type 2 DM phenotype compared to insulinopenic patients undergoing SPKT. However, survival and functional outcomes were similar, suggesting that pretransplantation C-peptide levels should not be used exclusively to determine candidacy for SPKT.

Pancreas transplantation: The Wake Forest experience in the new millennium

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

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

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

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

Transplant options for patients with type 2 diabetes and chronic kidney disease

Chronic kidney disease (CKD) has become a real epidemic around the world, mainly due to ageing and diabetic nephropathy. Although diabetic nephropathy due to type 1 diabetes mellitus (T1DM) has been studied more extensively, the vast majority of the diabetic CKD patients suffer from type 2 diabetes mellitus (T2DM). Renal transplantation has been established as a first line treatment for diabetic nephropathy unless there are major contraindications and provides not only a better quality of life, but also a significant survival advantage over dialysis. However, T2DM patients are less likely to be referred for renal transplantation as they are usually older, obese and present significant comorbidities. As pre-emptive renal transplantation presents a clear survival advantage over dialysis, all T2DM patients with CKD should be referred for early evaluation by a transplant center. The transplant center should have enough time in order to examine their eligibility focusing on special issues related with diabetic nephropathy and explore the best options for each patient. Living donor kidney transplantation should always be considered as the first line treatment. Otherwise, the patient should be listed for deceased donor kidney transplantation. Recent progress in transplantation medicine has improved the "transplant menu" for T2DM patients with diabetic nephropathy and there is an ongoing discussion about the place of simultaneous pancreas kidney (SPK) transplantation in well selected patients. The initial hesitations about the different pathophysiology of T2DM have been forgotten due to the almost similar short- and long-term results with T1DM patients. However, there is still a long way and a lot of ethical and logistical issues before establishing SPK transplantation as an ordinary treatment for T2DM patients. In addition recent advances in bariatric surgery may offer new options for severely obese T2DM patients with CKD. Nevertheless, the existing data for T2DM patients with advanced CKD are rather scarce and bariatric surgery should not be considered as a cure for diabetic nephropathy, but only as a bridge for renal transplantation.

Kidney transplant options for the diabetic patient

For patients with diabetes and progressive chronic kidney disease, kidney transplantation is the optimal mode of renal replacement therapy, with or without a pancreas transplant. Additional benefits of pancreas transplant have become increasingly apparent due to advances in surgical outcomes and immunosuppression, and may be reasonably considered even in selected patients with type 2 diabetes. In general, pancreas transplantation is associated with long-term survival advantages despite an increased short-term morbidity and mortality risk. This is true with simultaneous pancreas kidney transplantation or pancreas after kidney transplantation compared to kidney transplantation alone, regardless of kidney donor status (living or deceased). Individual patient preferences, comorbidities, and expected waiting time influence selection of transplant modality, rather than a clear survival benefit of one strategy versus the other. In selected patients with type 2 diabetes, recent outcomes data support cautious utilization of simultaneous pancreas kidney transplantation when a living kidney donor transplant is not an option. The purpose of this review is to summarize current data regarding kidney and pancreas transplant treatment options in patients with both type 1 and 2 diabetes and the influence of current organ allocation policies to better understand the advantages and disadvantages of each of these strategies.