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.

Combined liver transplantation and sleeve gastrectomy: Report of a brief-interval staged approach.

Pretransplantation bariatric surgery in patients with high Model for End-Stage Liver Disease (MELD) score is fraught with risks. Bariatric surgery after liver transplantation (LT) may be complicated by surgical adhesions but could have advantages if performed at the time of transplantation. We investigated a method of brief-interval staging combining LT and sleeve gastrectomy (SG). LT recipients with a body mass index (BMI) > 40 kg/m 2 received an SG during the same hospitalization as the LT (LT/SG), at the same time as a planned brief-interval return to the operating room for biliary anastomosis. Differences in intraoperative attributes of the LT (Stage 1) versus SG (Stage 2) procedures were analyzed using Wilcoxon signed-rank test with significance p < 0.05 and compared with patients with obesity having a two-stage LT without SG. A total of 14 cases {median MELD score 33 (interquartile range [IQR], 18-40)} were compared with 28 controls; 60% were critically ill prior to surgery with mechanical ventilation, vasopressors, or continuous renal replacement therapy. Median interval between procedures was 16.1 (IQR, 12.5-22.7) hours for cases and 12.2 (IQR, 11.1-16.6) hours for controls, p  = 0.27. Median BMI at LT/SG was 47.0 (IQR, 41.7-51.3) kg/m 2 versus 38.1 (IQR, 35.7-39.8) kg/m 2 for controls, p < 0.001. At 1 year, median excess body weight loss was 74.0% (IQR, 46.2%-78.7%) in cases and 15.8% (IQR, -5.4% to 62.6%) in controls, p  = 0.13; total weight loss was 38.1% (IQR, 23.9-42.9) in cases versus 7.7% (IQR, -2.4% to 27.6%) for controls, p  = 0.03. Graft survival at 1 year was 92.9% for cases and 89.3% for controls with similar early postoperative outcomes. This proof-of-concept study revealed that a brief-interval SG during LT is feasible in patients with high MELD and resulted in sustained weight loss at 1 year with similar graft survival. Further studies are needed to determine an optimal strategy.

Deceased donor vein extension grafts for right living donor kidney transplantation.

INTRODUCTION: In an effort to maximize living donor kidney utilization, we describe the use of deceased donor vein extension grafts for right-sided living donor kidneys and report our single-center experience using this technique. METHODS: A retrospective review of kidney transplant recipients (KTR) who received a right living donor kidney with deceased donor vein extension graft. Recipient demographics, postoperative graft function, and surgical complications were reviewed. Living donor nephrectomies were performed laparoscopically. Vein grafts were obtained from recent deceased donor procurements. End-to-end anastomosis of the graft to the renal vein was performed prior to implantation. RESULTS: Thirty-eight KTR received a right kidney transplant with deceased donor extension grafts. The median recipient age and BMI were 53.0 years and 29.3 kg/m2 . Total 71% were male. Ninety-five percent of grafts displayed immediate graft function, with two recipients requiring temporary dialysis due to anaphylaxis from induction therapy. Median serum creatinine at two weeks was 1.6 mg/dL and at three months was 1.5 mg/dL. There were no graft thromboses. CONCLUSION: Utilization of deceased donor extension grafts for short right renal veins is a simple technique that expands the donor pool for living donor renal transplantation. Our experience resulted in no technical complications and excellent early graft function.

Survival following liver transplantation for locally advanced, unresectable intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) has previously been considered a contraindication to liver transplantation (LT). However, recent series showed favorable outcomes for LT after neoadjuvant therapy. Our center developed a protocol for neoadjuvant therapy and LT for patients with locally advanced, unresectable iCCA in 2010. Patients undergoing LT were required to demonstrate disease stability for 6 months on neoadjuvant therapy with no extrahepatic disease. During the study period, 32 patients were listed for LT and 18 patients underwent LT. For transplanted patients, the median number of iCCA tumors was 2, and the median cumulative tumor diameter was 10.4 cm. Patients receiving LT had an overall survival at 1-, 3-, and 5-years of 100%, 71%, and 57%. Recurrences occurred in seven patients and were treated with systemic therapy and resection. The study population had a higher than expected proportion of patients with genetic alterations in fibroblast growth factor receptor (FGFR) and DNA damage repair pathways. These data support LT as a treatment for highly selected patients with locally advanced, unresectable iCCA. Further studies to identify criteria for LT in iCCA and factors predicting survival are warranted.

In silico deceased donor intervention research: A potential accelerant for progress.

Progress in deceased donor intervention research has been limited. Development of an in silico model of deceased donor physiology may elucidate potential therapeutic targets and provide an efficient mechanism for testing proposed deceased donor interventions. In this study, we report a preliminary in silico model of deceased kidney donor injury built, calibrated, and validated based on data from published animal and human studies. We demonstrate that the in silico model behaves like animal studies of brain death pathophysiology with respect to upstream markers of renal injury including hemodynamics, oxygenation, cytokines expression, and inflammation. Therapeutic hypothermia, a deceased donor intervention studied in human trials, is performed to demonstrate the model's ability to mimic an established clinical trial. Finally, future directions for developing this concept into a functional, clinically applicable model are discussed.

Pre-transplant T-cell Clonality: An Observational Study of a Biomarker for Prediction of Sepsis in Liver Transplant Recipients.

OBJECTIVE: This study investigated the ability of pre-transplant T-cell clonality to predict sepsis after liver transplant (LT). SUMMARY BACKGROUND DATA: Sepsis is a leading cause of death in LT recipients. Currently, no biomarkers predict sepsis before clinical symptom manifestation. METHODS: Between December 2013 and March 2018, our institution performed 478 LTs. After exclusions (eg, patients with marginal donor livers, autoimmune disorders, nonabdominal multi-organ, and liver retransplantations), 180 consecutive LT were enrolled. T-cell characterization was assessed within 48 hours before LT (immunoSEQ Assay, Adaptive Biotechnologies, Seattle, WA). Sepsis-2 and Sepsis-3 cases, defined by presence of acute infection plus ≥2 SIRS criteria, or clinical documentation of sepsis, were identified by chart review. Receiver-operating characteristic analyses determined optimal T-cell repertoire clonality for predicting post-LT sepsis. Kaplan-Meier and Cox proportional hazard modeling assessed outcome-associated prognostic variables. RESULTS: Patients with baseline T-cell repertoire clonality ≥0.072 were 3.82 (1.25, 11.40; P = 0.02), and 2.40 (1.00, 5.75; P = 0.049) times more likely to develop sepsis 3 and 12 months post-LT, respectively, when compared to recipients with lower (<0.072) clonality. T-cell repertoire clonality was the only predictor of sepsis 3 months post-LT in multivariate analysis (C-Statistic, 0.75). Adequate treatment resulted in equivalent survival rates between both groups: (93.4% vs 96.2%, respectively, P = 0.41) at 12 months post-LT. CONCLUSIONS: T-cell repertoire clonality is a novel biomarker predictor of sepsis before development of clinical symptoms. Early sepsis monitoring and management may reduce post-LT mortality. These findings have implications for developing sepsis-prevention protocols in transplantation and potentially other populations.

Donation after circulatory death liver transplantation: An in-depth analysis and propensity score-matched comparison.

BACKGROUND: Careful donor-recipient matching and reduced ischemia times have improved outcomes following donation after circulatory death (DCD) liver transplantation (LT). This study examines a single-center experience with DCD LT including high-acuity and hospitalized recipients. METHODS: DCD LT outcomes were compared to a propensity score-matched (PSM) donation after brain death (DBD) LT cohort (1:4); 32 DCD LT patients and 128 PSM DBD LT patients transplanted from 2008 to 2018 were included. Analyses included Kaplan-Meier estimates and Cox proportional hazards models examining patient and graft survival. RESULTS: Median MELD score in the DCD LT cohort was 22, with median MELD of 27 for DCD LT recipients with decompensated cirrhosis. No difference in mortality or graft loss was found (p < .05) between DCD LT and PSM DBD LT at 3 years post-transplant, nor was DCD an independent risk factor for patient or graft survival. Post-LT severe acute kidney injury was similar in both groups. Ischemic-type biliary lesions (ITBL) occurred in 6.3% (n = 2) of DCD LT recipients, resulting in 1 graft loss and 1 death. CONCLUSION: This study supports that DCD LT outcomes can be similar to DBD LT, with a low rate of ITBL, in a cohort including high-acuity recipients. Strict donor selection criteria, ischemia time minimization, and avoiding futile donor/recipient combinations are essential considerations.

Going the distance for procurement of donation after circulatory death livers for transplantation-Does reimbursement reflect reality?

Donation after circulatory death (DCD) liver transplantation (LT) has increased slowly over the past decade. Given that transplant surgeons generally determine liver offer acceptance, understanding surgeon incentives and disincentives is paramount. The purpose of this study was to assess aggregate travel distance per successful DCD versus deceased after brain death (DBD) liver procurement as a surrogate for surgeon time expenditure and opportunity cost. All consecutive liver offers made to Michigan Medicine from 2006 to 2017 were analyzed. Primary outcome was the summative travel distance (spent on all attempted procurements) per successful liver procurement that resulted in LT. Donation after circulatory death liver offer acceptance was lower than DBD liver offers, as was proportion of successful procurements among accepted offers. Overall, 10 275 miles were travelled for accepted DCD liver offers, resulting in 23 successful procurements (mean 447 miles per successful DCD liver procurement). For accepted DBD liver offers, 197 299 miles were travelled, resulting in 863 successful procurements (mean 229 miles per successful DBD liver procurement). On average, each successful DCD liver procurement required 218 more miles of travel than each successful DBD liver procurement. Current reimbursement policies poorly reflect increased surgeon travel (and time) expenditures between DCD and DBD liver offers.

A Step toward Standardization: Results of two National Surveys of Best Practices in Donation after Circulatory Death Liver Recovery and Recommendations from The American Society of Transplant Surgeons and Association of Organ Procurement Organizations.

Donation after circulatory death (DCD) liver allografts remain underutilized. Inconsistent processes for DCD procurement may contribute to allograft discard. Optimal surgical and organ procurement organization (OPO) practices for DCD liver recovery should be developed and adopted. DCD practice surveys were distributed to transplant surgeons and OPO leadership. DCD liver recovery best practices were assembled based on survey data, literature review, and subject-matter expert consensus opinion. Data were obtained from transplant surgeons (n = 188) and OPO leadership (n = 48 OPOs). Surgeons preferred attending physician presence at recovery (72.4%); while only 27.7% of OPOs require this. Pre-withdrawal communication huddle (Surgeons: 88.7%; OPOs: 93.8%) and administration of pre-withdrawal heparin (Surgeons: 90.6%; OPOs: 84.8%) are widely accepted. Surgical preference for withdrawal of support is in the operating room (89.3%); OPO practice varies dependent upon hospital and family requirements. Functional donor warm ischemic time (fDWIT) start time is variable, while fDWIT end time is agreed upon as initiation of aortic flush by surgeons (81%) and OPOs (81%). DCD liver recovery practices including mandatory communication huddle, pre-withdrawal heparin administration, and clearly defined start and end of fDWIT should be implemented nationally. Creating a set of best practices for DCD recovery guidelines is necessary for improving DCD liver utilization.

Unexplained fever after pancreas transplantation.

BACKGROUND: Fever occurs frequently early after pancreas transplant, however, the exact cause is often undetermined. Limited data are available on pancreas recipients experiencing unexplained, noninfectious fever. This study aims to characterize unexplained fever (UF) in pancreas recipients and its effect on patient and graft outcomes. METHODS: We performed a retrospective cohort study of UF among consecutive pancreas or simultaneous pancreas-kidney transplant recipients from 1 January 2011 to 31 August 2015. Classification of UF was based on the absence of positive cultures, radiologic findings, and other diagnostic features of infection or rejection. RESULTS: Twenty-three of 92 (25%) patients experienced UF. The UF episode first occurred at a mean of 31 ± 17 days post-transplant and accounted for 34 admissions with an average length of stay of 5.1 ± 3.4 days. Intravenous corticosteroid was administered following confirmation of negative diagnostic tests in 77% of patients, with fever resolution occurring in all. No differences were seen in rates of biopsy-proven rejection, graft loss, death, or documented infections compared to UF-free patients during the first-year post-transplant. CONCLUSION: UF is a common cause for readmission following pancreas transplantation. While the etiology of UF remains difficult to identify, UF occurrence was not associated with adverse outcomes during the first-year post-transplant.

Bloodstream infections after solid organ transplantation: clinical epidemiology and antimicrobial resistance (2016-21).

Background: Solid organ transplant (SOT) recipients are at risk of bloodstream infections (BSIs) with MDR organisms (MDROs). Objectives: To describe the epidemiology of BSI in the year after several types of SOT, as well as the prevalence of MDRO infections in this population. Methods: We conducted a single-centre, retrospective study of kidney, liver, heart, and multi-organ transplantation patients. We examined BSIs ≤1 year from SOT and classified MDRO phenotypes for Staphylococcus aureus, enterococci, Enterobacterales, Pseudomonas aeruginosa and Candida spp. We compared BSI characteristics between SOT types and determined risk factors for 90 day mortality. Results: We included 2293 patients [1251 (54.6%) kidney, 663 (28.9%) liver, 219 (9.6%) heart and 160 (7.0%) multi-organ transplant]. Overall, 8.5% of patients developed a BSI. BSIs were most common after multi-organ (23.1%) and liver (11.3%) transplantation (P < 0.001). Among 196 patients with BSI, 323 unique isolates were recovered, 147 (45.5%) of which were MDROs. MDROs were most common after liver transplant (53.4%). The most frequent MDROs were VRE (69.8% of enterococci) and ESBL-producing and carbapenem-resistant Enterobacterales (29.2% and 27.2% of Enterobacterales, respectively). Mortality after BSI was 9.7%; VRE was independently associated with mortality (adjusted OR 6.0, 95% CI 1.7-21.3). Conclusions: BSI incidence after SOT was 8.5%, with a high proportion of MDROs (45.5%), especially after liver transplantation. These data, in conjunction with local antimicrobial resistance patterns and prescribing practices, may help guide empirical antimicrobial selection and stewardship practices after SOT.

Effect of a Hispanic outreach program on referral and liver transplantation volume at a single center.

BACKGROUND: Although Hispanic patients have high rates of end-stage liver disease and liver cancer, for which liver transplantation (LT) offers the best long-term outcomes, they are less likely to receive LT. Studies of end-stage renal disease patients and kidney transplant candidates have shown that targeted, culturally relevant interventions can increase the likelihood of Hispanic patients receiving kidney transplant. However, similar interventions remain largely unstudied in potential LT candidates. METHODS: Referrals to a single center in Texas with a large Hispanic patient population were compared before (01/2018-12/2019) and after (7/2021-6/2023) the implementation of a targeted outreach program. Patient progress toward LT, reasons for ineligibility, and differences in insurance were examined between the two eras. RESULTS: A greater proportion of Hispanic patients were referred for LT after the implementation of the outreach program (23.2% vs 26.2%, p = 0.004). Comparing the pre-outreach era to the post-outreach era, more Hispanic patients achieved waitlisting status (61 vs 78, respectively) and received a LT (971 vs 82, respectively). However, the proportion of Hispanic patients undergoing LT dropped from 30.2% to 20.3%. In the post-outreach era, half of the Hispanic patients were unable to get LT for financial reasons (112, 50.5%). CONCLUSIONS: A targeted outreach program for Hispanic patients with end-stage liver disease effectively increased the total number of Hispanic LT referrals and recipients. However, many of the patients who were referred were ineligible for LT, most frequently for financial reasons. These results highlight the need for additional research into the most effective ways to ameliorate financial barriers to LT in this high-need community.

US Liver Transplant Outcomes After Normothermic Regional Perfusion vs Standard Super Rapid Recovery.

Importance: Normothermic regional perfusion (NRP) is an emerging recovery modality for transplantable allografts from controlled donation after circulatory death (cDCD) donors. In the US, only 11.4% of liver recipients who are transplanted from a deceased donor receive a cDCD liver. NRP has the potential to safely expand the US donor pool with improved transplant outcomes as compared with standard super rapid recovery (SRR). Objective: To assess outcomes of US liver transplants using controlled donation after circulatory death livers recovered with normothermic regional perfusion vs standard super rapid recovery. Design, Setting, and Participants: This was a retrospective, observational cohort study comparing liver transplant outcomes from cDCD donors recovered by NRP vs SRR. Outcomes of cDCD liver transplant from January 2017 to May 2023 were collated from 17 US transplant centers and included livers recovered by SRR and NRP (thoracoabdominal NRP [TA-NRP] and abdominal NRP [A-NRP]). Seven transplant centers used NRP, allowing for liver allografts to be transplanted at 17 centers; 10 centers imported livers recovered via NRP from other centers. Exposures: cDCD livers were recovered by either NRP or SRR. Main Outcomes and Measures: The primary outcome was ischemic cholangiopathy (IC). Secondary end points included primary nonfunction (PNF), early allograft dysfunction (EAD), biliary anastomotic strictures, posttransplant length of stay (LOS), and patient and graft survival. Results: A total of 242 cDCD livers were included in this study: 136 recovered by SRR and 106 recovered by NRP (TA-NRP, 79 and A-NRP, 27). Median (IQR) NRP and SRR donor age was 30.5 (22-44) years and 36 (27-49) years, respectively. Median (IQR) posttransplant LOS was significantly shorter in the NRP cohort (7 [5-11] days vs 10 [7-16] days; P < .001). PNF occurred only in the SRR allografts group (n = 2). EAD was more common in the SRR cohort (123 of 136 [56.1%] vs 77 of 106 [36.4%]; P = .007). Biliary anastomotic strictures were increased 2.8-fold in SRR recipients (7 of 105 [6.7%] vs 30 of 134 [22.4%]; P = .001). Only SRR recipients had IC (0 vs 12 of 133 [9.0%]; P = .002); IC-free survival by Kaplan-Meier was significantly improved in NRP recipients. Patient and graft survival were comparable between cohorts. Conclusion and Relevance: There was comparable patient and graft survival in liver transplant recipients of cDCD donors recovered by NRP vs SRR, with reduced rates of IC, biliary complications, and EAD in NRP recipients. The feasibility of A-NRP and TA-NRP implementation across multiple US transplant centers supports increasing adoption of NRP to improve organ use, access to transplant, and risk of wait-list mortality.

Single-center Outcomes After Liver Transplantation With SARS-CoV-2-Positive Donors: An Argument for Increased Utilization.

Background: The COVID-19 pandemic has led to an increase in SARS-CoV-2-test positive potential organ donors. The benefits of life-saving liver transplantation (LT) must be balanced against the potential risk of donor-derived viral transmission. Although emerging evidence suggests that the use of COVID-19-positive donor organs may be safe, granular series thoroughly evaluating safety are still needed. Results of 29 consecutive LTs from COVID-19-positive donors at a single center are presented here. Methods: A retrospective cohort study of LT recipients between April 2020 and December 2022 was conducted. Differences between recipients of COVID-19-positive (n = 29 total; 25 index, 4 redo) and COVID-19-negative (n = 472 total; 454 index, 18 redo) deceased donor liver grafts were compared. Results: COVID-19-positive donors were significantly younger (P = 0.04) and had lower kidney donor profile indices (P = 0.04) than COVID-19-negative donors. Recipients of COVID-19-positive donor grafts were older (P = 0.04) but otherwise similar to recipients of negative donors. Donor SARS-CoV-2 infection status was not associated with a overall survival of recipients (hazard ratio, 1.11; 95% confidence interval, 0.24-5.04; P = 0.89). There were 3 deaths among recipients of liver grafts from COVID-19-positive donors. No death seemed virally mediated because there was no qualitative association with peri-LT antispike antibody titers, post-LT prophylaxis, or SARS-CoV-2 variants. Conclusions: The utilization of liver grafts from COVID-19-positive donors was not associated with a decreased overall survival of recipients. There was no suggestion of viral transmission from donor to recipient. The results from this large single-center study suggest that COVID-19-positive donors may be used safely to expand the deceased donor pool.

Revitalizing pancreas transplantation: creation of a hands-on training course for pancreas allograft procurement, backbench preparation, and transplantation.

Despite a steady increase in the number of organs available for transplant in the United States, over the last two decades there has been a precipitous decrease in the annual number of pancreas transplants performed. One overlooked consequence of this decline in pancreas transplant volume has been a decrease in experience in proper pancreas procurement and transplantation techniques for transplant surgeons as well as fewer trained abdominal transplant fellows entering the workforce certified for pancreas procurement and transplantation, with those achieving certification having less-developed judgment, skills, and experience. To augment current fellowship training and provide a concentrated experience in pancreas procurement and transplantation, the ASTS developed a hands-on surgical skills workshop focused on proper techniques for pancreas allograft procurement and backbench preparation.