Salvage Endovascular Thrombectomy for Splenic Vein Thrombosis After Pancreas Transplantation: A Single-Center Experience and Systematic Literature Review.

OBJECTIVES: Technical graft loss, usually thrombotic in nature, accounts for most of the pancreas grafts that are removed early after transplant. Although arterial and venous thrombosis can occur, the vein is predominantly affected, with estimated overall rate of thrombosis of 6% to 33%. In late diagnosis, the graft will need to be removed because thrombectomy will not restore its functionality. However, in early diagnosis, a salvage procedure should be attempted. MATERIALS AND METHODS: We conducted a retrospective, descriptive analysis of a prospective database of patients who underwent pancreas transplant from April 2008 to June 2020 at a single center. We evaluated post-transplant clinical glucose levels, imaging, treatment, and outcomes. We also performed a systematic review of publications for endovascular treatment of vascular graft thrombosis in pancreas transplant. RESULTS: In 67 pancreas transplants analyzed, 13 (19%) were diagnosed with venous thrombus. In 7 of 13 patients (54%), systemic anticoagulation was prescribed because of a non-occlusive thromboses, resulting in complete resolution for all 7 patients. Six patients (46%) required endovascular thrombectomy because of the presence of complete occlusive thrombosis; 4 of these patients (67%) needed a second procedure because of recurrence of the thrombosis. One of the 6 patients (17%) required a surgical approach, resulting in successful removal of the recurrent clot. Twelve of the 13 grafts (92%) were rescued. Graft survival at 1 year was 84%; graft survival at 3, 5, and 10 years remained at 70%. CONCLUSIONS: Pancreas vein thrombosis represents a frequent surgical complication and remains as a challenging problem. In our experience, early diagnoses and an endovascular approach combined with aggressive medical treatment and follow-up can be used for successful treatment and reduce graft loss.

Subclinical Pancreas Rejection on Protocol Biopsy Within the First Year of Simultaneous Pancreas Kidney Transplant.

This single-center retrospective study investigated subclinical rejection prevalence and significance in simultaneous pancreas and kidney transplant (SPKT) recipients. We analyzed 352 SPKT recipients from July 2003 to April 2022. Our protocol included pancreas allograft surveillance biopsies at 1, 4, and 12months post-transplant. After excluding 153 patients unable to undergo pancreas biopsy, our study cohort comprised 199 recipients. Among the 199 patients with protocol pancreas biopsies, 107 had multiple protocol pancreas biopsies in the first year, totaling 323. Subclinical rejection was identified in 132 episodes (41%). Of these, 72% were Grade 1, 20% were indeterminate, and 8% were Banff Grade 2 or higher. All episodes of subclinical rejection were treated. Rates of pancreas graft loss (10% vs. 7%) and clinical rejection (21% vs. 20%) at 3 years were similar between those with and without subclinical rejection. Subclinical rejection Banff Grade 2 or more was associated with poor pancreas graft survival HR of 5.5 (95% CI: 1.24-24.37, p = 0.025). Of 236 simultaneous protocol kidney and pancreas biopsies, 102 (43%) showed pancreas subclinical rejection, while only 17% had concurrent kidney subclinical rejection. Our findings suggest limited predictive value of pancreatic enzymes and euglycemia in detecting pancreas rejection. Furthermore, poor concordance existed between pancreas and kidney subclinical rejection.

Management of Failing Kidney and Pancreas Transplantations.

Survival rates for allografts have improved over the last 2 decades, yet failing allografts remains a challenge in the field of transplant. The risks of mortality and morbidity associated with failed allografts are compounded by infectious complications and metabolic abnormalities, emphasizing the need for a standardized approach to management. Management of failing allografts lacks consensus, highlighting the need for unified protocols to guide treatment protocols and minimize risks with postdialysis initiation. The decision to wean off immunosuppression depends on various factors, including living donor availability and infectious risks, necessitating improved coordination of care and a standard guideline. Treatment of failed pancreas focuses on glycemic control, with insulin as the mainstay, while considering surgical interventions such as graft pancreatectomy in advanced symptomatic cases. Navigating the complexities of failed allograft management demands a multidisciplinary approach and standardized stepwise protocol. Addressing the gaps in management plans for failing allografts and employing a systematic approach to transplant decisions will enhance patient outcomes and facilitate informed decision-making.

Posttransplant Lymphoproliferative Disease Following Pancreas Transplantation: A 40 Year Single-Center Experience.

BACKGROUND: Chronic immunosuppression following pancreas transplantation carries significant risk, including posttransplant lymphoproliferative disease (PTLD). We sought to define the incidence, risk factors, and long-term outcomes of PTLD following pancreas transplantation at a single center. METHODS: All adult pancreas transplants between February 1, 1983 and December 31, 2023 at the University of Minnesota were reviewed, including pancreas transplant alone (PTA), simultaneous pancreas-kidney transplants (SPK), and pancreas after kidney transplants (PAK). RESULTS: Among 2353 transplants, 110 cases of PTLD were identified, with an overall incidence of 4.8%. 17.3% were diagnosed within 1 year of transplant, 32.7% were diagnosed within 5 years, and 74 (67.3%) were diagnosed after 5 years. The overall 30-year incidence of PTLD did not differ by transplant type-7.4% for PTA, 14.2% for SPK, and 19.4% for PAK (p = 0.3). In multivariable analyses, older age and Epstein-Barr virus seronegativity were risk factors for PTLD, and PTLD was a risk factor for patient death. PTLD-specific mortality was 32.7%, although recipients with PTLD had similar median posttransplant survival compared to those without PTLD (14.9 year vs. 15.6 year, p = 0.9). CONCLUSIONS: PTLD following pancreas transplantation is associated with significant mortality. Although the incidence of PTLD has decreased over time, a high index of suspicion for PTLD following PTx should remain in EBV-negative recipients.

Accessibility of Percutaneous Biopsy in Retrocolic-Placed Pancreatic Grafts With a Duodeno-Duodenostomy.

Duodeno-duodenostomy (DD) has been proposed as a more physiological alternative to conventional duodeno-jejunostomy (DJ) for pancreas transplantation. Accessibility of percutaneous biopsies in these grafts has not yet been assessed. We conducted a retrospective study including all pancreatic percutaneous graft biopsies requested between November 2009 and July 2021. Whenever possible, biopsies were performed under ultrasound (US) guidance or computed tomography (CT) guidance when the US approach failed. Patients were classified into two groups according to surgical technique (DJ and DD). Accessibility, success for histological diagnosis and complications were compared. Biopsy was performed in 93/136 (68.4%) patients in the DJ group and 116/132 (87.9%) of the DD group (p = 0.0001). The graft was not accessible for biopsy mainly due to intestinal loop interposition (n = 29 DJ, n = 10 DD). Adequate sample for histological diagnosis was obtained in 86/93 (92.5%) of the DJ group and 102/116 (87.9%) of the DD group (p = 0.2777). One minor complication was noted in the DD group. The retrocolic position of the DD pancreatic graft does not limit access to percutaneous biopsy. This is a safe technique with a high histological diagnostic success rate.

Measuring the Impact of Postsimultaneous Pancreas-Kidney Transplantation Complications: Comparing the Comprehensive Complication Index and Clavien-Dindo Classification.

INTRODUCTION: The Clavien-Dindo classification (CDC) is commonly used for assessing postoperative complications; however, it may not be comprehensive. A comprehensive complication index (CCI) was introduced to address this limitation. This study aimed to compare the effectiveness of the CCI and CDC in evaluating the complications after simultaneous pancreas-kidney (SPK) transplantation. METHODS: Data were collected from patients who underwent SPK transplantation at our center between February 2018 and February 2021. Complications encountered during hospitalization were assessed using both the CDC and CCI. Linear regression analyses were performed to identify the factors related to postoperative length of stay (PLOS). RESULTS: Overall, 125 patients were included, with an average age of 46.87 years. Type 2 diabetes was present in 79% of the recipients. Among them, 117 patients experienced postoperative complications of CDC grades I (2.4%), II (57.6%), IIIa (8.0%), IIIb (9.6%), IVa (14.4%), IVb (0.8%), and V (0.8%) postoperative complications. The median CCI for the entire cohort was 37.2. Spearman's correlation analysis revealed significant associations between the CDC and PLOS and the CCI and PLOS. Notably, CCI exhibited a stronger correlation with PLOS (CCI: ρ = 0.698 vs. CDC: ρ = 0.524; p = 0.024). CONCLUSION: The CCI demonstrated a stronger correlation with PLOS than CDC. Our finding suggests that the CCI may be a useful tool for comprehensively assessing complications following SPK transplantation.

The Impact of Kidney/Pancreas Transplantation on Peripheral Arterial Disease.

INTRODUCTION: It is unclear whether kidney/pancreas (KP) transplantation will prevent the progression of peripheral arterial disease (PAD) in patients with insulin dependent diabetes (IDDM) and end-stage renal disease. We sought to determine the pre- and posttransplant prevalence of symptomatic PAD and changes in carotid artery intima-media thickness (IMT) in KP recipients. METHODS: In this single center study, outcomes were compared between KP recipients with and without a history of PAD. A subset of recipients underwent pre- and posttransplant IMT measurements. RESULTS: Among the study group (N = 107), 18 (17%) recipients admitted to a pretransplant history of symptomatic PAD, comprised 11 foot infections and 7 amputations (5 minor and 2 major). Baseline characteristics of age, gender, race, years of diabetes, dialysis history, smoking history, years of hypertension, and history of coronary artery disease (CAD) were equivalent between PAD and non-PAD cohorts. At a median follow-up of 60 months (IQR: 28, 110), 16 (15%) KP recipients had suffered a PAD event. In multivariate analysis, a pretransplant history of PAD (hazard ratio [HR] 9.66, p < 0.001) and CAD (HR 3.33, p = 0.04) were independent predictors of posttransplant PAD events. Among a subset of 20 recipients (3 with PAD), mean IMT measurements pretransplant and at a median of 24 (range 18-24) months posttransplant, showed no evidence of disease progression. CONCLUSION: Based on IMT measurements and clinical results, KP transplantation stabilized PAD in most patients, but did not alter outcomes of symptomatic PAD recipients. A pretransplant history of PAD and CAD was an independent predictor of posttransplant PAD events.

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.

Effect of pretransplant dialysis modalities on pancreas-kidney transplant outcomes: a systematic review and meta-analysis.

BACKGROUND: The impact of different pretransplant dialysis modalities on post-transplant outcomes for pancreas-kidney transplantation is currently unclear. This study aims to assess the association between pretransplant dialysis modalities [hemodialysis (HD) and peritoneal dialysis] and outcomes following pancreas-kidney transplantation. METHODS: The authors searched PubMed, EMBASE, and the Cochrane Library for relevant studies published from inception until 1 December 2023. The authors included studies that examined the relationship between pretransplant dialysis modalities and clinical outcomes for pancreas-kidney transplantation. The primary outcomes considered were patient, pancreas and kidney graft survival, and intra-abdominal infection. RESULTS: A total of 13 studies involving 1503 pancreas-kidney transplant recipients were included. Pretransplant HD was associated with improved pancreas graft survival (hazard ratio = 0.71, 95% confidence interval: 0.51-0.99, I ²=12%) and a decreased risk of intra-abdominal infection [odds ratio (OR)=0.69, 95% CI: 0.51-0.93, I ²=5%). However, no significant association was found between the dialysis modalities and patient or kidney graft survival. Furthermore, pretransplant HD was linked to a reduced risk of anastomotic leak (OR=0.32, 95% CI: 0.161-0.68, I ²=0%) and graft thrombosis (OR=0.56, 95% CI: 0.33-0.96, I ²=20%). CONCLUSION: Pretransplant HD is the preferred dialysis modality while awaiting pancreas-kidney transplantation, although well-designed prospective studies are needed to confirm these findings.

Surgical complications and technical failure of simultaneous pancreas-kidney transplantation: A 22-year experience from a single center.

Simultaneous pancreas-kidney transplantation (SPKT) is the best treatment for selected individuals with type 1 diabetes mellitus and end-stage renal disease. Despite advances in surgical techniques, donor and recipient selection, and immunosuppressive therapies, SPKT remains a complex procedure with associated surgical complications and adverse consequences. We conducted a retrospective study that included 263 SPKT procedures performed between May 2000, and December 2022. A total of 65 patients (25%) required at least one relaparotomy, resulting in an all-cause relaparotomy rate of 2.04 events per 100 in-hospital days. Lower donor body mass index was identified as an independent factor associated with reoperation (OR .815; 95% CI:  .725-.917, p = .001). Technical failure (TF) occurred in 9.9% of cases, primarily attributed to pancreas graft thrombosis, intra-abdominal infections, bleeding, and anastomotic leaks. Independent predictors of TF at 90 days included donor age above 36 years (HR 2.513; 95% CI 1.162-5.434), previous peritoneal dialysis (HR 2.503; 95% CI 1.149-5.451), and specific pancreas graft reinterventions. The findings highlight the importance of carefully considering donor and recipient factors in SPKT. The incidence of TF in our study population aligns with the recent series. Continuous efforts should focus on identifying and mitigating potential risk factors to enhance SPKT outcomes, thereby reducing post-transplant complications.

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.

Metastatic Merkel Cell Carcinoma After Simultaneous Pancreas-Kidney Transplantation: Fatal Outcomes.

Merkel cell carcinoma (MCC) is a rare, highly aggressive cutaneous malignancy. Immunosuppression increases the risk of MCC and is associated with poor prognosis. Organ transplant recipients (OTR) have worse overall survival (OS) than patients with immunosuppression due to other causes. Treating MCC after organ transplantation is challenging, as checkpoint inhibitor immunotherapy, the standard of care for treating MCC, increases the risk of transplant rejection. This paper reviews the cases of two simultaneous pancreas-kidney transplant (SPKT) recipients with MCC and explores the role of immunosuppression in the development of MCC. Immunosuppression was discontinued and checkpoint inhibitor therapy was initiated in the first patient and considered by the second patient. In both cases, treatment failed, and the patients died shortly after developing metastatic MCC. These cases illustrate the need for improved multidisciplinary treatment regimens for MCC in OTRs. J Drugs Dermatol. 2024;23(5):376-377.     doi:10.36849/JDD.8234  .

Efficacy and Safety Evaluation of Energy Devices in Bench Surgery for Pancreas Transplantation.

INTRODUCTION: Bench surgery for the preparation of deceased donor pancreatic grafts is labor-intensive and time-consuming. We hypothesized that energy devices could be used during bench surgery to decrease the bench surgery time. However, because bench surgery has two unique characteristics, wet conditions and no blood flow in the vessels, it is necessary to verify the safety and efficacy under such conditions. METHODS: In an animal tissue model, we validated both ultrasonic and bipolar energy devices: Harmonic Shears and the LigaSure (LS) vessel-sealing device by evaluating heat spread and pressure resistance under bench surgery conditions. In a clinical evaluation of the LS, we compared the outcomes of 22 patients in two different bench surgery groups: with and without the use of the LS. RESULTS: Clinically, the bench surgery time was significantly shorter in the LS group than that in the conventional group (P < 0.001). In the animal tissue experiments, the highest temperature in bench surgery conditions was 60.4°C after 1 s at a 5-mm distance in the LS group. Pressure resistance of ≥ 750 mmHg was achieved in almost all trials in both veins and arteries, with no difference between Harmonic Shears and LS. There was more surgical smoke visually in bench conditions versus in dry conditions and under half bite versus full bite conditions. CONCLUSIONS: The encouraging results of our exploratory clinical and animal studies of the energy devices suggest that they may be useful in the setting of bench surgery.

A Case Report of Modified Pancreatic Transplantation With a Limited Splenic Arteriovenous Fistula to Elude Thrombosis.

In classic pancreatic transplantation, the splenic artery and vein are ligated at the tail of the pancreas graft. This leads to slowed blood flow in the splenic vein and may cause thrombosis and graft loss. In this study, a patient received a pancreas after kidney transplantation. A modified surgical technique was used in the pancreatic graft preparation. The donor splenic artery and vein were anastomosed end to end at the tail of the pancreas. The splenic artery near the anastomosis was partially ligated, and an effective diameter of 2 mm was reserved to limit arterial blood pressure and flow. The patient recovered very well. Contrasted computed tomography scans on days 11 and 88 after pancreas transplantation indicated sufficient backflow of the splenic vein. We believe that this procedure may avoid the risk of splenic vein thrombosis after pancreas transplantation. This modified technique has not been reported in clinical cases previously and may help reduce the risk of thrombosis after pancreas transplantation.

A New Mouse Model of Whole Pancreas Transplant With Graft Blood Through the Portal Vein.

OBJECTIVES: Pancreas transplant is currently the most effective method for maintaining physiological blood sugar levels and reversing small blood vessel injuries. Our team developed a model of whole pancreas transplant based on microsurgical techniques following the investigation of more than 300 mice. MATERIALS AND METHODS: A mouse pancreatic transplant model is required to investigate the pathophysiological process of pancreas transplant and pancreatic preservation technologies. Recently, the segment-neck pancreas transplant has been the most utilized mouse pancreatic transplant model. The innovative mouse pancreatic transplant modelthat we developed in this study uses the whole pancreas and returns heart blood flow into the liver via the portal vein. RESULTS: With our mouse pancreatic transplant model, the survivalrate of mice aftertransplant was >80%, and the success rate of pancreatic transplant was >90%. CONCLUSIONS: The segment-neck and the whole pancreas model can guarantee that the transplanted pancreas functions effectively, and both have excellent postoperative outcomes, survivalrates and pancreatic active rates.

Risk factors and outcomes of persistent post-transplant hypotension among simultaneous pancreas and kidney transplant recipients.

BACKGROUND: The risk factors and outcomes associated with post- transplant hypotension after simultaneous pancreas and kidney (SPK) Transplantation are poorly defined. METHODS: SPK recipients at our center between 2010 and 2021 with functioning pancreas and kidney grafts for >6 months were included. Recipients were then divided into three groups based on active medications for the treatment of hypo-or hypertension at 6-months post-transplant: those with normal blood pressure (NBP) not requiring medication (NBP group), those on antihypertensive medications (HTN group), and those on medications for hypotension (fludrocortisone and/or midodrine) (Hypotensive group). RESULTS: A total of 306 recipients were included in the study: 54 (18%) in the NBP group, 215 (70%) in the HTN group, and 37 (12%) in the Hypotensive group. On multivariate analysis, the use of T-depleting induction (aHR = 9.64, p = .0001, 95% Cl = 3.12-29.75), pre-transplant use of hypotensive medications (aHR = 4.53, p = .0003, 95% Cl = 1.98-10.38), and longer duration of dialysis (aHR = 1.02, p = .01, 95% Cl = 1.00-1.04) were associated with an increased risk of post-transplant hypotension. Post-transplant hypotension was not associated with an increased risk of death-censored kidney or pancreatic allograft failure, or patient death. CONCLUSION: Hypotension was common even 6 months post-SPK transplantation. With appropriate management, hypotension was not associated with detrimental graft or patient outcomes.

Management of ectopic intestinal variceal bleeding following pancreatic transplant: Two cases.

Ectopic variceal bleeding is a potentially under recognized source of gastrointestinal (GI) hemorrhage. While vascular complications following pancreatic transplant are relatively common, the development of symptomatic ectopic venous varices has rarely been reported. We report two patients with a remote history of simultaneous kidney pancreas transplant (SPK) presenting two decades after transplant with an occult GI bleed. In both cases, a lengthy diagnostic course was required. The varices were treated with coil embolization via transhepatic approach. Our findings add to the limited literature on this topic and aid in the recognition, diagnosis, and management of this unusual presentation.