Extended pancreas donor program - the EXPAND study rationale and study protocol

Elevated liver enzymes at the time of deceased donor organ donation do not affect recipient or pancreas allograft survival following pancreas transplantation

BACKGROUND

There is a lack of data on the impact of donor liver function tests (LFTs) on pancreas transplantation outcomes. Understanding their contribution could expand the donor pool.

METHODS

Using the UNOS database, data from January 2010-2022 was retrospectively analyzed. Multivariable cox regressions were performed to evaluate the association between LFTs (AST, ALT and total bilirubin levels), graft failure and mortality up to three years post-transplant.

RESULTS

9138 pancreas transplants were completed. Multivariate analysis showed no association between donor AST values > 500 U/L and increased rates of graft failure (p = 0.826) or mortality (p = 0.836). Similar findings were noted for donor ALT values > 500 U/L (p = 0.522 and p = 0.997, respectively). There was no correlation with graft failure (p = 0.322) or mortality (p = 0.423) for total bilirubin levels >3 mg/dL.

CONCLUSION

LFTs in the deceased pancreas donor did not increase risk of graft failure or mortality following pancreas transplantation. Elevated LFTs should not serve as absolute contraindications to transplant.

An Examination of Donor Factors That Impact the Results of the Glucagon Stimulation Test as an Assessment of the Pancreatic Graft Endocrine Function

OBJECTIVES

Delta C-peptide derived by the glucagon stimulation test is a reliable value for the evaluation of the pancreatic endocrine function after pancreas transplantation. We examined the associations between delta C-peptide as pancreatic graft endocrine function and donor background factors.

METHODS

Sixty-five cases of pancreatic transplantation from brain-dead donors, which were performed in our facility, were enrolled in this study. Enrolled recipients underwent a glucagon stimulation test within 1 to 3 months after transplantation to evaluate the pancreatic graft endocrine function with delta C-peptide to compare donor background factors.

RESULTS

The following factors were associated with significant deterioration of the delta C-peptide: age of 50 years or greater, death from cerebrovascular accident, hemoglobin A1c level of 5.6% or greater, creatinine level of 1.0 mg/dL or greater, C-reactive protein level of 25 mg/dL or greater, and sodium level of 150 mmol/L or greater. In addition, increased numbers of these donor factors indicated significantly greater deterioration of the posttransplant pancreatic endocrine function ( P < 0.001).

CONCLUSIONS

To secure insulin independence after pancreas transplantation, which means maintaining a delta C-peptide level of 1.0 ng/mL or greater on a glucagon stimulation test, the utilization of donors, who possesses more than equal to 3 of the donor factors identified in this study, should be carefully considered.

Clinical use of donation after circulatory death pancreas for islet transplantation

Due to a shortage of donation after brain death (DBD) organs, donation after circulatory death (DCD) is increasingly performed. In the field of islet transplantation, there is uncertainty regarding the suitability of DCD pancreas in terms of islet yield and function after islet isolation. The aim of this study was to investigate the potential use of DCD pancreas for islet transplantation. Islet isolation procedures from 126 category 3 DCD and 258 DBD pancreas were performed in a 9-year period. Islet yield after isolation was significantly lower for DCD compared to DBD pancreas (395 515 islet equivalents [IEQ] and 480 017 IEQ, respectively; p = .003). The decrease in IEQ during 2 days of culture was not different between the two groups. Warm ischemia time was not related to DCD islet yield. In vitro insulin secretion after a glucose challenge was similar between DCD and DBD islets. After islet transplantation, DCD islet graft recipients had similar graft function (AUC C-peptide) during mixed meal tolerance tests and Igls score compared to DBD graft recipients. In conclusion, DCD islets can be considered for clinical islet transplantation.

Expanding pancreas donor pool by evaluation of unallocated organs after brain death: Study protocol clinical trial (SPIRIT Compliant)

BACKGROUND

Pancreas graft quality directly affects morbidity and mortality rates after pancreas transplantation (PTx). The criteria for pancreas graft allocation are restricted, which has decreased the number of available organs. Suitable pancreatic allografts are selected based on donor demographics, medical history, and the transplant surgeon's assessment of organ quality during procurement. Quality is assessed based on macroscopic appearance, which is biased by individual experience and personal skills. Therefore, we aim to assess the histopathological quality of unallocated pancreas organs to determine how many unallocated organs are potentially of suitable quality for PTx.

METHODS AND ANALYSIS

This is a multicenter cross-sectional explorative study. The demographic data and medical history of donor and cause of rejection of the allocation of graft will be recorded. Organs of included donors will be explanted and macroscopic features such as weight, color, size, and stiffness will be recorded by 2 independent transplant surgeons. A tissue sample of the organ will be fixed for further microscopic assessments. Histopathologic assessments will be performed as soon as a biopsy can be obtained. We will evaluate up to 100 pancreata in this study.

RESULT

This study will evaluate the histopathological quality of unallocated pancreas organs from brain-dead donors to determine how many of these unallocated organs were potentially suitable for transplantation based on a histopathologic evaluation of organ quality.

CONCLUSION

The comprehensive findings of this study could help to increase the pancreas graft pool, overcome organ shortage, reduce the waiting time, and also increase the number of PTx in the future. Registration number: ClinicalTrials.gov: NCT04127266.

The Role of Pre-Procurement Pancreas Suitability Score (P-PASS) and Pancreas Donor Risk Index (PDRI) in the Outcome of Simultaneous Pancreas and Kidney or Pancreas After Kidney Transplantation

Background

The pre-procurement pancreas suitability score (P-PASS) and the pancreas donor risk index (pDRI) are established predictive scores for graft survival and patient outcome following pancreatic transplantation. This retrospective study aimed to evaluate the predictive value of P-PASS and pDRI following simultaneous pancreas and kidney (SPK) transplantation, or pancreas after kidney (PAK) transplantation, and the clinical impact of donor-specific factors on the postoperative graft and recipient outcome at a single transplant center.

Material/Methods

The study included 105 patients who underwent SPK (n=104) or PAK (n=4) between 2000 and 2017. Donor-specific and recipient-specific parameters were recorded. Kaplan-Meier analysis and Cox regression analysis were used to assess the outcome after transplantation.

Results

Overall, the mean 1-year and 5-year pancreas graft survival and patient survival rates were 78.7% and 93.2%, and 76.9% and 90.0%, respectively. The postoperative outcome in patients with a P-PASS score of <17 was not significantly different when compared with patients with a score of ≥17. A P-PASS score of ≥17 was significantly associated with early pancreas graft loss (p=0.04). There was no significant difference in postoperative outcome between patients with high pDRI and low pDRI. Smoking of donor (p=0.046) was a risk factor and coronary heart disease of recipient (p=0.003) had a significant effect on survival of pancreas graft.

Conclusions

This study showed that P-PASS and pDRI were not reliable predictors of outcome after pancreas transplantation and that specific characteristics of the donor and recipient must be evaluated when predicting the outcome of pancreas transplantation.

Extended Pancreas Donor Program-The EXPAND Study: A Prospective Multicenter Trial Testing the Use of Pancreas Donors Older Than 50 Years

BACKGROUND

Pancreas transplantation is the only curative treatment option for patients with juvenile diabetes. Organ shortage and restrictive allocation criteria are the main reasons for increasing waitlists, leading to severe morbidity and mortality. We designed a study to increase the donor pool with extended donor criteria (EDC) organs (donor age, 50-60 years; body mass index, 30-34 kg/m).

METHODS

Utilization of EDC organs required the implementation of a new allocation system within Eurotransplant. The study was a prospective, multicenter, 2-armed trial. The primary endpoint was pancreas function after 3 months. Rejection episodes, kidney function, and waitlist time were secondary endpoints. Patients receiving an EDC organ were study group patients; recipients of standard organs were control group patients. Follow-up was 1 year.

RESULTS

Seventy-nine patients were included in 12 German centers, 18 received EDC organs and 61 received standard organs. Recipient demographics were similar. Mean EDC donor age was 51.4 ± 5 years versus 31.7 ± 12 in the control group. Insulin-free graft survival was 83.3% for EDC and 67.2% for standard organs (P = 0.245) after 3 months. One-year pancreas survival was 83.3% and 83.5% in the EDC versus standard group. One-year kidney allograft survival was approximately 94% in both groups. Rejection episodes and morbidity were similar.

CONCLUSIONS

The Extended Pancreas Donor Program (EXPAND) shows in a prospective trial that selected EDC organs of donors older than 50 years can be used with outcomes similar to standard-criteria organs, therefore showing potential to reduce organ shortage and waiting times. This study substantiates the full implementation of EDC organs in a pancreas allocation system.

A systematic review and meta-analysis of cold in situ perfusion and preservation for pancreas transplantation

BACKGROUND

This study aimed to identify the most effective solution for in situ perfusion/preservation of the pancreas in donation after brain death donors, in addition to optimal in situ flush volume(s) and route(s) during pancreas procurement.

METHODS

Embase, Medline and Cochrane databases were utilized (1980-2017). Articles comparing graft outcomes between two or more different perfusion/preservation fluids (University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK) and/or Celsior) were compared using random effects models where appropriate.

RESULTS

Thirteen articles were included (939 transplants). Confidence in available evidence was low. A higher serum peak lipase (standardized mean difference 0.47, 95% CI 0.23-0.71, I² = 0) was observed in pancreatic grafts perfused/preserved with HTK compared to UW, but there were no differences in one-month pancreas allograft survivals or early thrombotic graft loss rates. Similarly, there were no significant differences in the rates of graft pancreatitis, thrombosis and graft survival between UW and Celsior solutions, and between aortic-only and dual aorto-portal perfusion.

CONCLUSION

UW cold perfusion may reduce peak serum lipase, but no quality evidence suggested UW cold perfusion improves graft survival and reduces thrombosis rates. Further research is needed to establish longer-term graft outcomes, the comparative efficacy of Celsior, and ideal perfusion volumes.

Guidelines for the assessment and acceptance of potential brain-dead organ donors

Organ transplantation is the only alternative for many patients with terminal diseases. The increasing disproportion between the high demand for organ transplants and the low rate of transplants actually performed is worrisome. Some of the causes of this disproportion are errors in the identification of potential organ donors and in the determination of contraindications by the attending staff. Therefore, the aim of the present document is to provide guidelines for intensive care multi-professional staffs for the recognition, assessment and acceptance of potential organ donors.

Single-center experience using organs after rescue allocation for pancreas transplant in the eurotransplant region

OBJECTIVES

Because of the shortage of available organs for transplants, graft allocation polices have been modified recently. This report deals with the effect of using organs after rescue allocation for pancreas transplant in a single center in the Eurotransplant Region to possibly expand the donor pool.

MATERIALS AND METHODS

A retrospective analysis was performed. Between 2007 and 2010, thirty-one pancreas transplants were performed at the University Hospital of Leipzig, in Leipzig, Germany. Among these, 7 cases used rescue organs. These organs had been officially offered to, but rejected by, at least 3 consecutive transplant centers. Donor/recipient and clinical/laboratory transplant/posttransplant outcomes from patients receiving rescue organs were collected and were compared with organs from conventional donors.

RESULTS

Mean donor age was greater in the rescue organ group than in the conventional donor group (28.3 ± 10.7 y vs 23.0 ± 12.5 y). During follow-up (2.3 ± 0.6 y rescue organ group vs 3.9 ± 1.2 y conventional donor group), patient, kidney, and pancreas graft survival rates were 85% in all 3 categories in the rescue organ group, whereas outcomes for conventional donors were 88%, 85%, and 83%. Incidences of pancreatic graft thrombosis, delayed graft function, acute and late rejection episodes (eg, perioperative complications) were comparable between groups. No differences existed between mean serum urea levels and mean HbA1c levels between groups 2 years after transplant. Whereas 2 years after surgery, mean serum creatinine levels (rescue organ group, 78.8 ± 21.0 μmol/L vs 114.3 ± 28.4 μmol/L in the conventional donor group) showed significant differences between groups.

CONCLUSIONS

Results are promising. Further pro-spective studies are warranted to evaluate routine transplant of organs after rescue allocation.

Pancreas transplantation: a treatment option for people with diabetes

Since the first pancreas transplants in the early 1960s, whole-organ pancreas transplantation, either alone or combined with kidney transplantation, has become commonplace in many countries around the world. Whole-organ pancreas transplantation is available in the UK, with ~200 transplants currently carried out per year. Patient survival and pancreas graft outcome rates are now similar to other solid organ transplant programmes, with high rates of long-term insulin independence. In the present review, we will discuss whole-pancreas transplantation as a treatment for diabetes, focusing on indications for transplantation, the nature of the procedure performed, graft survival rates and the consequences of pancreas transplantation on metabolic variables and the progression of diabetes-related complications.

Pancreas transplantation: solid organ and islet

Transplantation of the pancreas, either as a solid organ or as isolated islets of Langerhans, is indicated in a small proportion of patients with insulin-dependent diabetes in whom severe complications develop, particularly severe glycemic instability and progressive secondary complications (usually renal failure). The potential to reverse diabetes has to be balanced against the morbidity of long-term immunosuppression. For a patient with renal failure, the treatment of choice is often a simultaneous transplant of the pancreas and kidney (SPK), whereas for a patient with glycemic instability, specifically hypoglycemic unawareness, the choice between a solid organ and an islet transplant has to be individual to the patient. Results of SPK transplantation are comparable to other solid-organ transplants (kidney, liver, heart) and there is evidence of improved quality of life and life expectancy, but the results of solitary pancreas transplantation and islets are inferior with respect to graft survival. There is some evidence of benefit with respect to the progression of secondary diabetic complications in patients with functioning transplants for several years.