Pancreas Preservation: Hypothermic Oxygenated Perfusion to Improve Graft Reperfusion.

BACKGROUND: The clinical standard for pancreas preservation for transplantation is static cold storage (SCS). Oxygenation during preservation has been shown to be advantageous in clinical studies. This study evaluates the efficiency of different oxygenation modalities during hypothermic pancreas preservation. METHODS: Thirty-two porcine pancreases were procured in a controlled donation after circulatory death model and were divided to be preserved in 8 groups: (1) SCS, (2) hypothermic machine perfusion (HMP), (3) hypothermic oxygenated machine perfusion (HOPE) with 21% oxygen, (4) HOPE and 100%, (5) SCS and oxygen carrier, M101, (6) HMP and M101, (7) HOPE 21% and M101, and (8) HOPE 100% and M101. All the groups underwent 24 h of hypothermic preservation, followed by 2 h of normothermic reperfusion. Oxygen partial pressures were assessed using parenchymal probes. Perfusion parameters, perfusate samples, and tissue biopsies were analyzed. RESULTS: This study showed that HMP was linked to higher tissue oxygen partial pressures, lower succinate levels, and better reperfusion parameters. Furthermore, the addition of M101 to either SCS or HMP was associated with lower succinate and creatinine phosphokinase accumulation, suggesting a protective effect against ischemia. CONCLUSIONS: Our research has demonstrated the efficacy of machine perfusion in hypothermic conditions in providing oxygen to the pancreas during preservation and conditioning the pancreatic microvasculature for reperfusion during transplantation. Furthermore, the addition of M101 suggests a protective effect on the graft from ischemia.

The role of donor hypertension and angiotensin II in the occurrence of early pancreas allograft thrombosis.

Background: About 10-20% of pancreas allografts are still lost in the early postoperative period despite the identification of numerous detrimental risk factors that correlate with graft thrombosis. Methods: We conducted a multicenter study including 899 pancreas transplant recipients between 2000 and 2018. Early pancreas failure due to complete thrombosis, long-term pancreas, kidney and patient survivals were analyzed and adjusted to donor, recipient and perioperative variables using a multivariate cause-specific Cox model stratified to transplant centers. Results: Pancreas from donors with history of hypertension (6.7%), as well as with high body mass index (BMI), were independently associated with an increased risk of pancreas failure within the first 30 post-operative days (respectively, HR= 2.57, 95% CI from 1.35 to 4.89 and HR= 1.11, 95% CI from 1.04 to 1.19). Interaction term between hypertension and BMI was negative. Donor hypertension also impacted long-term pancreas survival (HR= 1.88, 95% CI from 1.13 to 3.12). However, when pancreas survival was calculated after the postoperative day 30, donor hypertension was no longer a significant risk factor (HR= 1.22, 95% CI from 0.47 to 3.15). A lower pancreas survival was observed in patients receiving a pancreas from a hypertensive donor without RAAS (Renin Angiotensin Aldosterone System) blockers compared to others (50% vs 14%, p < 0.001). Pancreas survival was similar among non-hypertensive donors and hypertensive ones under RAAS blockers. Conclusion: Donor hypertension was a significant and independent risk factor of pancreas failure. The well-known pathogenic role of renin-angiotensin-aldosterone system seems to be involved in the genesis of this immediate graft failure.

Banff 2022 pancreas transplantation multidisciplinary report: Refinement of guidelines for T cell-mediated rejection, antibody-mediated rejection and islet pathology. Assessment of duodenal cuff biopsies and noninvasive diagnostic methods.

The Banff pancreas working schema for diagnosis and grading of rejection is widely used for treatment guidance and risk stratification in centers that perform pancreas allograft biopsies. Since the last update, various studies have provided additional insight regarding the application of the schema and enhanced our understanding of additional clinicopathologic entities. This update aims to clarify terminology and lesion description for T cell-mediated and antibody-mediated allograft rejections, in both active and chronic forms. In addition, morphologic and immunohistochemical tools are described to help distinguish rejection from nonrejection pathologies. For the first time, a clinicopathologic approach to islet pathology in the early and late posttransplant periods is discussed. This update also includes a discussion and recommendations on the utilization of endoscopic duodenal donor cuff biopsies as surrogates for pancreas biopsies in various clinical settings. Finally, an analysis and recommendations on the use of donor-derived cell-free DNA for monitoring pancreas graft recipients are provided. This multidisciplinary effort assesses the current role of pancreas allograft biopsies and offers practical guidelines that can be helpful to pancreas transplant practitioners as well as experienced pathologists and pathologists in training.

Sterile Pancreas Inflammation during Preservation and after Transplantation.

The pancreas is very susceptible to ischemia-reperfusion injury. Early graft losses due to pancreatitis and thrombosis represent a major issue after pancreas transplantation. Sterile inflammation during organ procurement (during brain death and ischemia-reperfusion) and after transplantation affects organ outcomes. Sterile inflammation of the pancreas linked to ischemia-reperfusion injury involves the activation of innate immune cell subsets such as macrophages and neutrophils, following tissue damage and release of damage-associated molecular patterns and pro-inflammatory cytokines. Macrophages and neutrophils favor tissue invasion by other immune cells, have deleterious effects or functions, and promote tissue fibrosis. However, some innate cell subsets may promote tissue repair. This outburst of sterile inflammation promotes adaptive immunity activation via antigen exposure and activation of antigen-presenting cells. Better controlling sterile inflammation during pancreas preservation and after transplantation is of utmost interest in order to decrease early allograft loss (in particular thrombosis) and increase long-term allograft survival. In this regard, perfusion techniques that are currently being implemented represent a promising tool to decrease global inflammation and modulate the immune response.

Very Low Dose Anti-Thymocyte Globulins Versus Basiliximab in Non-Immunized Kidney Transplant Recipients.

The choice between Basiliximab (BSX) or Anti-Thymocyte Globulin (ATG) as induction therapy in non-immunized kidney transplant recipients remains uncertain. Whilst ATG may allow steroid withdrawal and a decrease in tacrolimus, it also increases infectious complications. We investigated outcomes in non-immunized patients receiving a very low dosage of ATG versus BSX as induction. Study outcomes were patient/graft survival, cumulative probabilities of biopsy proven acute rejection (BPAR), infectious episode including CMV and post-transplant diabetes (PTD). Cox, logistic or linear statistical models were used depending on the studied outcome and models were weighted on propensity scores. 100 patients received ATG (mean total dose of 2.0 mg/kg) and 83 received BSX. Maintenance therapy was comparable. Patient and graft survival did not differ between groups, nor did infectious complications. There was a trend for a higher occurrence of a first BPAR in the BSX group (HR at 1.92; 95%CI: [0.77; 4.78]; p = 0.15) with a significantly higher BPAR episodes (17% vs 7.3%, p = 0.01). PTD occurrence was significantly higher in the BSX group (HR at 2.44; 95%CI: [1.09; 5.46]; p = 0.03). Induction with a very low dose of ATG in non-immunized recipients was safe and associated with a lower rate of BPAR and PTD without increasing infectious complications.

Primary Graft Function and 5 Year Insulin Independence After Pancreas and Islet Transplantation for Type 1 Diabetes: A Retrospective Parallel Cohort Study.

In islet transplantation (ITx), primary graft function (PGF) or beta cell function measured early after last infusion is closely associated with long term clinical outcomes. We investigated the association between PGF and 5 year insulin independence rate in ITx and pancreas transplantation (PTx) recipients. This retrospective multicenter study included type 1 diabetes patients who underwent ITx in Lille and PTx in Nantes from 2000 to 2022. PGF was assessed using the validated Beta2-score and compared to normoglycemic control subjects. Subsequently, the 5 year insulin independence rates, as predicted by a validated PGF-based model, were compared to the actual rates observed in ITx and PTx patients. The study enrolled 39 ITx (23 ITA, 16 IAK), 209 PTx recipients (23 PTA, 14 PAK, 172 SPK), and 56 normoglycemic controls. Mean[SD] PGF was lower after ITx (ITA 22.3[5.2], IAK 24.8[6.4], than after PTx (PTA 38.9[15.3], PAK 36.8[9.0], SPK 38.7[10.5]), and lower than mean beta-cell function measured in normoglycemic control: 36.6[4.3]. The insulin independence rates observed at 5 years after PTA and PAK aligned with PGF predictions, and was higher after SPK. Our results indicate a similar relation between PGF and 5 year insulin independence in ITx and solitary PTx, shedding new light on long-term transplantation outcomes.

Incidence, Risk Factors and Outcomes of Kidney and Liver Cyst Infection in Kidney Transplant Recipient With ADPKD.

Introduction: Cyst infection is a known complication of autosomal dominant polycystic kidney disease (ADPKD). Here, we describe incidence, risk factors, clinical presentation, and outcomes of cyst infection in kidney transplant recipient. Methods: We conducted a single-center retrospective cohort study of patients with ADPKD with renal allografts between January 1, 2009, and October 31, 2020. Cyst infection diagnosis was based on previously described clinical and radiological criteria, using positron emission tomography when available. Results: A total of 296 patients with ADPKD with renal allografts were included, and 21 patients experienced 22 episodes of cyst infection over a median follow-up of 4 (2-7) years. The cumulative incidence rate was 3% at 1 year, 6 % at 5 years, and 12% at 10 years after transplantation. In multivariate analysis, history of cyst infection before transplantation was the only significant risk factor identified to predict the occurrence of cyst infection after kidney transplantation (hazard ratio [HR] 3.47, 95% CI 1.29-9.31). The clinical presentation at diagnosis of cyst infection included isolated fever in 5 (23%) episodes, acute kidney injury in 12 (55%), and severe sepsis/septic shock in 3 (14%) episodes. Among the 16 (73%) episodes with culture positivity, Escherichia coli was the most common pathogen. There was no difference between early (≤1 year after transplantation) and late (>1 year) cyst infection episodes in terms of clinical presentation and outcomes. Cyst infection was significantly associated with graft loss (HR 3.93, 95% CI 1.21-12.80), but no causal relationship could be established. Conclusion: Incidence of cyst infection in ADPKD after kidney transplantation is low, history of cyst infection representing the main risk factor.

[Genetic screening is essential in polycystic kidney disease: It is never too late!] / Une polykystose peut en cacher une autre. Il n'est jamais trop tard pour l'analyse génétique !

In France, numerous patients suffered from chronic kidney disease on polycystic kidney disorder. If PKD1 and PKD2 inactivating mutations are the most prevalent, several other genetic polycystic kidney diseases are responsible for similar kidney features and may be associated with severe extrarenal phenotypes. Genetic analysis in front of a polycystic disorder is not systematic, but is essential to assess the genetic diagnosis, discuss the intensity of treatment (vaptan) and precise the prognostic and the transmission of the phenotype. We detailed the case of a patient with end stage renal disease due to a polycystic kidney disease. Genetic analysis at 70 year of age revealed an oral-facial-digital syndrome type 1. The diagnosis had an important impact in the familial history and to attach the extrarenal phenotype to the syndrome. Our case illustrates that, in front of a polycystic kidney disease (even in aged patients with end stage renal disease) genetic screening is essential, for the propositus and their family and to take care of the extrarenal manifestations.

Occurrence of De novo Donor-Specific Antibodies After COVID-19 in Kidney Transplant Recipients Is Low Despite Immunosuppression Modulation.

Introduction: Decreased immunosuppression has been proposed for kidney transplant recipients infected with coronavirus disease 2019 (COVID-19), but the impact on the alloreactive immune response during and after infection has been poorly investigated. We evaluated the occurrence of antihuman leukocyte antigen (HLA) donor-specific antibodies (DSAs) (post-COVID-19) and rejection episodes after COVID-19 with particular focus on immunosuppression modulation. Methods: Kidney transplant recipients from 2 French institutions had anti-HLA antibody screening before and after COVID-19. Management of immunosuppression, rejection episodes, COVID-19 severity, inflammatory markers, and antiviral therapies were recorded. Results: From 251 recruited patients, 72 were excluded because of COVID-19-related death (n = 25) and incomplete immunologic follow-up (n = 47). Among the remaining 179 included patients, almost half were hospitalized (49.2%). Antimetabolites were interrupted in 47% of patients (82% in hospitalized, median time of resumption of 23 days and in 15% nonhospitalized, median time of resumption of 7 days). Calcineurin inhibitors were interrupted in 12% of patients (all hospitalized, median time of resumption of 11 days). The incidence of post-COVID-19 DSA was 4% (8% and 0% in hospitalized and nonhospitalized, respectively). Allograft rejection occurred in 3 patients (1.7%) and all were hospitalized. Younger age, transplantation <1 year, and preexisting DSA were more frequently observed in patients with post-COVID-19 DSA, whereas inflammatory markers, lymphopenia, and use of antiviral therapies were not. Conclusion: The incidence of post-COVID-19 DSA among COVID-19-positive kidney transplant recipients was low (4%) despite a significant decrease in immunosuppression and was mainly restricted to high-risk immunologic patient's status. COVID-19 severity was not associated with post-COVID-19 DSA and/or rejection.

Kidney transplantation from expanded criteria donors: an increased risk of urinary complications - the UriNary Complications Of Renal Transplant (UNyCORT) study.

OBJECTIVES: To assess the impact of expanded criteria donors (ECD) on urinary complications in kidney transplantation. PATIENTS AND METHODS: The UriNary Complications Of Renal Transplant (UNyCORT) is a cohort study based on the French prospective Données Informatisées et VAlidées en Transplantation/Computerized and VAlidated Data in Transplantation (DIVAT) cohort. Data were extracted between 1 January 2002 and 1 January 2018 with 1-year minimum follow-up, in relation to 44 pre- and postoperative variables. ECD status was included according to United Network for Organ Sharing (UNOS) definition. The primary outcome of the UNyCORT study was the association between the donor's ECD/standard criteria donors (SCD) status and urinary complications at 1 year in uni- and multivariate analysis. Sub-group analysis, stratified analysis on ECD/SCD donor's status and transplant failure analysis were then conducted. RESULTS: Between 1 January 2002 and 1 January 2018, 10 279 kidney transplants in adult recipients were recorded within the DIVAT network. A total of 8559 (83.4%) donors were deceased donors and 1699 (16.6%) were living donors (LD). Among donation after circulatory death (DCD) donors, 224 (2.85%) were uncontrolled DCD and 93 (1.09%) were controlled DCD donors. A total of 3617 (43.9%) deceased donors were ECD. The overall urological complication rate was 16.26%. The donor's ECD status was significantly associated with an increased risk of urological complications at 1 year in multivariate analysis (odds ratio: 1.50, 95% CI 1.31-1.71; P < 0.001) and especially with stenosis and ureteric fistulae at 1 year. There is no association with LD, uncontrolled and controlled DCD. The placement of an endo-ureteric stent was beneficial in preventing urinary complications in all donors and particularly in ECD donors. CONCLUSION: The donor's ECD status is associated with a higher likelihood of stenosis and ureteric fistulae at 1 year. Recipients of grafts from ECD donors should probably be considered for closer urological monitoring and systematic preventive measures.

Side-to-Side Duodenojejunal Anastomosis Volvulus After Pancreas Transplant: A Case Report.

Pancreas transplant is one of the known most effective treatments for type 1 diabetes mellitus and is associated with improved survival and quality of life for patients. Most centers use a direct side-to-side anastomosis between the donor's duodenum and jejunum, and we describe a rare complication that affected 2 patients. The 2 patients each received a simultaneous kidney-pancreas transplant and presented with side-to-side duodenojejunal anastomosis volvulus. We describe the clinical and radiological presentations and then propose an effective management method. Side-to-side duodenojejunal anastomosis volvulus after pancreas transplant is an exceptional complication, and there are special radiological and surgical manage-ment techniques to allow efficient treatment.