Stepwise development and expansion of an abdominal normothermic regional perfusion program for donation after circulatory determination of death organ procurement.

INTRODUCTION: Normothermic regional perfusion (NRP) represents an innovative technology that improves the outcomes for liver and kidney recipients of donation after circulatory determination of death (DCD) organs but protocols for abdominal-only NRP (A-NRP) DCD are lacking in the US. METHODS: We describe the implementation and expansion strategies of a transplant-center-based A-NRP DCD program that has grown in volume, geographical reach, and donor acceptance parameters, presented as four eras. RESULTS: In the implementation era, two donors were attempted, and one liver graft was transplanted. In the local expansion era, 33% of attempted donors resulted in transplantation and 42% of liver grafts from donors who died within the functional warm ischemic time (fWIT) limit were transplanted. In the Regional Expansion era, 25% of attempted donors resulted in transplantation and 50% of liver grafts from donors who died within the fWIT limit were transplanted. In the Donor Acceptance Expansion era, 46% of attempted donors resulted in transplantation and 72% of liver grafts from donors who died within the fWIT limit were transplanted. Eight discarded grafts demonstrated a potential opportunity for utilization. CONCLUSION: The stepwise approach to building an A-NRP program described here can serve as a model for other transplant centers.

A cost comparison of liver acquisition fees for donation after circulatory death versus donation after brain death donors.

Donation after circulatory death (DCD) donors now represent over 30% of the deceased donor pool in the United States. Compared to donation after brain death, DCD is less likely to result in transplantation. For each potential donor whose organs cannot be utilized for transplantation (ie, dry run), fees are associated with the attempted donation, which add to the overall costs of organ acquisition. To better characterize the true costs of DCD liver acquisition, we performed a cost comparison of the fees associated with organ acquisition for DCD versus donation after brain death at a single transplant institute that comprises 2 liver transplant centers. Cost, recipient, and transportation data for all cases, including fees associated with liver acquisition from July 1, 2019, to October 31, 2021, were collected. We found that the total cost of DCD liver acquisition per liver transplant was $15,029 more than that for donation after brain death donation, with 18% of the costs of the DCD transplant attributed to dry runs. Overall, the costs associated with DCD transplantation accounted for 34.5% of the total organ acquisition costs; however, DCD transplantation accounted for 30.3% of the transplantation volume. Because the expansion of DCD is essential to increasing the availability of liver grafts for transplantation, strategies need to be implemented to decrease the costs associated with dry runs, including using local recovery, transferring donors to hospitals close to transplant centers, and performing more prerecovery organ analysis. Moreover, these strategies are needed to ensure that financial disincentives to DCD procurement and utilization do not reverse the gains made by expanding the organ donor pool using machine perfusion technologies.

Elevated tacrolimus levels among COVID-19 kidney transplant recipients are associated with worse disease severity and clinical outcomes.

BACKGROUND: The therapeutic effects of immunosuppressive drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections causing coronavirus disease 2019 (COVID-19) are being actively investigated. However, COVID-19's potential effects on serum calcineurin inhibitor levels have only been described recently. This study aimed to evaluate COVID-19's effect on tacrolimus levels in renal transplant recipients with moderate to severe symptoms and to assess their potential correlation with disease severity. MATERIALS AND METHODS: We retrospectively investigated 50 kidney transplant recipients with moderate to severe COVID-19. Their tacrolimus trough level on admission was compared to baseline levels, and their laboratory measurements and clinical course were reviewed on days 1 (admission), 7, 14, and 28. RESULTS: We found that 90% of patients had admission tacrolimus trough levels above baseline, with a mean increase of 176%. In addition, 71% had tacrolimus trough levels ≥ 50% above baseline, and 40% had supra-therapeutic trough levels of > 15 ng/mL. Supra-therapeutic trough levels were associated with greater hypoxemic respiratory failure, acute kidney injury, and increased 30-day mortality. CONCLUSION: Elevated tacrolimus levels occur in many renal transplant recipients with moderate to severe COVID-19 and are associated with worse clinical outcomes. Close drug monitoring is crucial to avoid toxicities and minimize over-immunosuppression complications.

Utilization of a SARS-CoV-2-positive donor for liver transplantation.

Liver transplantation rates have been negatively affected by the pandemic caused by coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current practice in the liver transplant community is to avoid utilizing SARS-CoV-2-positive donors for liver transplantation unless there is a compelling reason such as recipient illness severity. In this case, we report the use of a donor who had a positive exposure to and symptom history for COVID-19 and tested positive for SARS-CoV-2 on admission for a liver transplant recipient with primary sclerosing cholangitis and a Model of End-Stage Liver Disease score of 23 with no known COVID-19 exposures. We focus on the decision to accept this particular organ, as well as the discussion with the recipient about the unknowns of disease transmission and risk associated with this donor. The current case argues that transplant programs should begin to consider low-risk donors with positive SARS-CoV-2 testing for recipients who have the potential to benefit from liver transplantation, which may not only be those with the most severe illness.

Longitudinal profiling of plasma and urine metabolites during liver regeneration in living liver donors.

BACKGROUND: Knowledge of metabolic processes affected by major hepatectomy (MHx), and the metabolic pathways involved in liver regeneration and recovery of function, is limited and mainly derived from animal models. Assessment of restoration of hepatic function is essential in human living liver donors (LD). METHODS: We used a targeted metabolomic approach to longitudinally quantify changes in plasma and urine biomarkers from healthy LD. The biomarkers were analyzed before MHx and at scheduled intervals up to 12 months thereafter. RESULTS: Marked changes were found in the concentration of 15 primary and secondary plasma bile acids. Most significant changes occurred 2 days after MHx and persisted for up to 3 months. In addition, there were significant changes in acylcarnitine, phospholipid, and amino acid metabolism. The sum of aromatic amino acids and the Fischer ratio, both metabolic markers of liver damage, and the symmetrically demethylated arginine to arginine ratio, a marker of kidney function, were affected. CONCLUSIONS: This is the first comprehensive longitudinal study investigating metabolic processes during recovery of liver function after MHx in LD. It provides further evidence of full restoration of metabolic processes 3 months after MHx and supports future investigation to understand how metabolic changes affect donors' hepatic function.

Cost Analysis of Liver Acquisition Fees Before and After Acuity Circle Policy Implementation.

Importance: Acuity circles (AC) liver allocation policy was implemented to eliminate donor service area geographic boundaries from liver allocation and to decrease variability in median Model of End-stage Liver Disease (MELD) score at transplant and wait list mortality. However, the broader sharing of organs was also associated with more flights for organ procurements and higher costs associated with the increase in flights. Objective: To determine whether the costs associated with liver acquisition changed after the implementation of AC allocation. Design, Setting, and Participants: This single-center cost comparison study analyzed fees associated with organ acquisition before and after AC allocation implementation. The cost data were collected from a single transplant institute with 2 liver transplant centers, located 30 miles apart, in different donation service areas. Cost, recipient, and transportation data for all cases that included fees associated with liver acquisition from July 1, 2019, to October 31, 2020, were collected. Exposures: Primary liver offer acceptance with associated organ procurement organization or charter flight fees. Main Outcomes and Measures: Specific fees (organ acquisition, surgeon, import, and charter flight fees) and total fees per donor were collected for all accepted liver donors with at least 1 associated fee during the study period. Results: Of 213 included donors, 171 were used for transplant; 90 of 171 (52.6%) were male, and the median (interquartile range) age of donors was 41.0 (30.0-52.8) years in the pre-AC period and 36.9 (24.0-48.8) years in the post-AC period. There was no significant difference in the post-AC compared with pre-AC period in median (range) MELD score (24 [8-40] vs 25 [6-40]; P = .27) or median (range) match run sequence (15 [1-3951] vs 10 [1-1138]; P = .31), nor in mean (SD) distance traveled (155.83 [157.00] vs 140.54 [144.33] nautical miles; P = .32) or percentage of donors requiring flights (58.5% [69 of 118] vs 56.8% [54 of 95]; P = .82). However, costs increased significantly in the post-AC period: total cost increased 16% per accepted donor (mean [SD] of $52 966 [13 278] vs $45 725 [9300]; P < .001) and 55% per declined donor (mean [SD] of $15 865 [3942] vs $10 217 [4853]; P < .001). Contributing factors included more than 2-fold increases in the proportions of donors incurring import fees (31.4% [37 of 118] vs 12.6% [12 of 95]; P = .002) and surgeon fees (19.5% [23 of 118] vs 9.5% [9 of 95]; P = .05), increased acquisition fees (10% increase; mean [SD] of $43 860 [3266] vs $39 980 [2236]; P < .001), and increased flight expenses (43% increase; mean [SD] of $12 904 [6066] vs $9049 [5140]; P = .002). Conclusions and Relevance: The unintended consequences of implementing broader sharing without addressing organ acquisition fees to account for increased importation between organ procurement organizations must be remedied to contain costs and ensure viability of transplant programs.

Serum sickness induced by alemtuzumab in a kidney-pancreas transplant recipient.

Serum sickness is an immune-complex-mediated hypersensitivity reaction that was first noted in the early 1900s in patients receiving heterologous antisera, such as horse antitetanus or antidiphtheria serum. This condition is primarily self-limited; however, in its acute state, it can cause severe symptoms of fever, rash, polyarthritis, or polyarthralgias. In solid organ transplantation, this condition is frequently reported in association with the use of rabbit anti-thymocyte globulin and chimeric murine monoclonal antibodies such as rituximab. Alemtuzumab, designed as a humanized monoclonal antibody against CD52, is expected to be less immunogenic. Here, we report a case of serum sickness associated with alemtuzumab induction therapy in a kidney-pancreas dual-organ recipient.

Selective screening imaging of the aortoiliac arterial system in kidney transplant candidates with non-contrast pelvic computed tomography.

Non-contrast pelvic computed tomography (CT) can detect severe iliac artery calcifications that present technical contraindications to kidney transplantation (TCT). We screened 454 asymptomatic patients with a history of any of the following: hemodialysis >10 years, diabetes mellitus >20 years, coronary artery disease (CAD) with percutaneous or surgical interventions, carotid disease, diabetes with below-/above-knee amputations, and heart-kidney transplantation candidacy. Patients with normal dorsalis pedis and/or tibialis posterior pulses were not screened. A total of 8.4% had severe calcifications with TCT; CT determined laterality for implantation in 13.9%. No patients with the following characteristics were classified as TCT: age <40 years, hemodialysis >10 years, carotid arterial disease, prior lower extremity amputation, or heart-kidney transplantation candidacy. CAD was associated with TCT in univariate though not multivariate analysis. Limiting screening to patients >40 years, with DM >20 years, or with CAD, 9.8% had a TCT and CT determined transplant laterality in 14.2%. Screening for severe iliac artery calcifications is useful for selected kidney transplantation candidates over age 40. It can assist with laterality choice or surgeon determination of TCT. Cost and radiation exposure risks should be weighed against the morbidity risks from unnecessary surgery.

Dallas UtErus Transplant Study: Early Outcomes and Complications of Robot-assisted Hysterectomy for Living Uterus Donors.

BACKGROUND: Uterus transplantation is a treatment for absolute uterine infertility and can be performed with living and deceased donors. Given the safety and increased utilization of robotic assistance with other gynecologic and transplant donor operations, we adopted a robot-assisted approach to donor hysterectomy. This study compared early outcomes and morbidity of the robot-assisted approach to donor hysterectomy with the traditionally performed open approach and addressed whether the robot-assisted approach is safe and offers advantages for the donor. METHODS: Our institution has performed 18 living donor hysterectomies for uterus transplantation. This retrospective review compared the last 5 cases utilizing a robot-assisted technique and vaginal extraction of the uterus graft with the first 13 cases performed with an open laparotomy technique. Demographic, intraoperative, and postoperative data were examined. RESULTS: There were no differences between the robot-assisted and the open living donor group with respect to age, body mass index, or gynecological history. Although the median operative time was shorter for the open approach (6.27 versus 10.46 h), the donors' median estimated blood loss, length of hospital stay, and length of sick leave were less with the robot-assisted approach. There was no conversion to open hysterectomy in the robot-assisted cases, and the incidence of complications was similar between the 2 groups. There was no difference in early graft function. CONCLUSIONS: These preliminary results show that robot-assisted living donor hysterectomy is feasible and safe for the donors; it allows a faster postoperative recovery and the same early graft function.

The Evolution of Transplantation From Saving Lives to Fertility Treatment: DUETS (Dallas UtErus Transplant Study).

OBJECTIVE: We report the results of the first 20 uterus transplants performed in our institution. SUMMARY BACKGROUND DATA: Uterus transplantation (UTx) aims at giving women affected by absolute uterine-factor infertility the possibility of carrying their own pregnancy. UTx has evolved from experimental to an established surgical procedure. METHODS: The Dallas Uterus Transplant Study (DUETS) program started in 2016. The uterus was transplanted in orthotopic position with vascular anastomoses to the external iliac vessels and removed when 1 or 2 live births were achieved. Immunosuppression lasted only for the duration of the uterus graft. RESULTS: Twenty women, median age 29.7 years, enrolled in the study, with 10 in phase 1 and 10 in phase 2. All but 2 recipients had a congenital absence of the uterus. Eighteen recipients received uteri from living donors and 2 from deceased donors. In phase 1, 50% of recipients had a technically successful uterus transplant, compared to 90% in phase 2. Four recipients with a technical success in phase 1 have delivered 1 or 2 babies, and the fifth recipient with a technical success is >30 weeks pregnant. In phase 2, 2 recipients have delivered healthy babies and 5 are pregnant. CONCLUSIONS: UTx is a unique type of transplant; whose only true success is a healthy child birth. Based on results presented here, involving refinement of the surgical technique and donor selection process, UTx is now an established solution for absolute uterine-factor infertility.

Effect of subcutaneous tissue depth on outcomes of kidney transplantation.

Although post-kidney transplant (KT) wound complications are associated with elevated body mass index (BMI), BMI is not an accurate surrogate of obesity. On the other hand, subcutaneous depth (SQD) measurement is a direct marker of truncal obesity. We examined outcomes of differing intraoperative SQD measurements in 113 KT-only recipients over 20 months. Recipients' median age was 51 years; median BMI, 28 kg/m2; and mean SQD, 2.9 cm. Patients were stratified into groups of SQD ≤2.5 cm, >2.5-5 cm, and >5 cm. An SQD of >2.5 to 5 cm correlated with a BMI of 30 kg/m2 (obesity) and an SQD >5 cm correlated with a BMI >35 kg/m2 (severe obesity). Degree of SQD was not associated with more frequent technical complications such as fascial dehiscence, lymphocele formation, renal artery thrombosis/stenosis, urine leak, or ureteral stenosis. However, an SQD >2.5 cm was a risk factor for requiring a wound vacuum-assisted closure device. There was no difference in graft or patient survival among the three SQD groups. Obesity, as measured directly by SQD, was not associated with increased technical complications or poor outcomes after KT. As expected, there was a higher incidence of wound complications in the higher SQD groups requiring intervention.

Significance of measured intraoperative portal vein flows after thrombendvenectomy in deceased donor liver transplantations with portal vein thrombosis.

Adequate portal vein (PV) flow in liver transplantation is essential for a good outcome, and it may be compromised in patients with portal vein thrombosis (PVT). This study evaluated the impact of intraoperatively measured PV flow after PV thrombendvenectomy on outcomes after deceased donor liver transplantation (DDLT). The study included 77 patients over a 16-year period who underwent PV thrombendvenectomy with complete flow data. Patients were classified into 2 groups: high PV flow (>1300 mL/minute; n = 55) and low PV flow (≤1300 mL/minute; n = 22). Postoperative complications and graft survival were analyzed according to the PV flow. The 2 groups were similar in demographic characteristics. Low PV flow was associated with higher cumulative rates of biliary strictures (P = 0.02) and lower 1-, 2-, and 5-year graft survival (89%, 85%, and 68% versus 64%, 55%, and 38%, respectively; P = 0.002). There was no difference in the incidence of postoperative PVT between the groups (1.8% versus 9.1%; P = 0.19). No biliary leaks or hepatic artery thromboses were reported in either group. By multivariate analyses, age >60 years (hazard ratio [HR], 3.04, 95% confidence interval [CI], 1.36-6.82; P = 0.007) and low portal flow (HR, 2.31; 95% CI, 1.15-4.65; P = 0.02) were associated with worse survival. In conclusion, PV flow <1300 mL/minute after PV thrombendvenectomy for PVT during DDLT was associated with higher rates of biliary strictures and worse graft survival. Consideration should be given to identifying reasons for low flow and performing maneuvers to increase PV flow when intraoperative PV flows are <1300 mL/minute. Liver Transplantation 23 1032-1039 2017 AASLD.

Low Measured Hepatic Artery Flow Increases Rate of Biliary Strictures in Deceased Donor Liver Transplantation: An Age-Dependent Phenomenon.

BACKGROUND: This study was conducted to determine effect of lower measured hepatic arterial (HA) flow (<400 mL/min) on biliary complications and graft survival after deceased donor liver transplantation. Hepatic artery is the main blood supply to bile duct and lack of adequate HA flow is thought to be a risk factor for biliary complications. METHODS: A retrospective review of 1300 patients who underwent deceased donor liver transplantation was performed. Patients with arterial complications were excluded to eliminate potential contribution to biliary complications from HA thrombosis. Patients were divided into low (<400 mL/min; N = 201) and high (≥400 mL/min; N = 1099) HA flow groups. Incidence of biliary complications and graft survival were analyzed. RESULTS: HA flows less than 400 mL/min were associated with increased rate of biliary strictures in younger donors (<50 years old), and in patients with duct-to-duct anastomoses (P = 0.028). Lower HA flows were associated with decreased graft survival (P = 0.013). Donor older than 50 years was associated with increased rate of biliary strictures (hazard ratio [HR], 1.67; 95% confidence interval [CI], 1.14-2.45; P = 0.0085) and graft failure (HR, 1.68; 95% CI, 1.35-2.1; P <0.0001) on multivariate analyses. HA flow less than 400 mL/min was associated with biliary strictures (HR, 1.53; 95% CI, 1.04-2.24; P = 0.0297) on univariate analysis only. CONCLUSIONS: HA flow less than 400 mL/min was associated with higher rate of biliary strictures in younger donors with duct-to-duct reconstruction and lower graft survival. A consideration should be given to increase the intraoperative HA flow to prevent biliary strictures in such patients.

Inferior vena cava reconstruction for leiomyosarcoma of Zone I-III requiring complete hepatectomy and bilateral nephrectomy with autotransplantation.

The inferior vena cava (IVC) is the most common site of leiomyosarcomas arising from a vascular origin. Leiomyosarcomas of the IVC are categorized by anatomical location. Zone I refers to the infrarenal portion of the IVC, Zone II from the hepatic veins to the renal veins, and Zone III from the right atrium to the hepatic veins. This is a rare presentation of a Zone I-III leiomyosarcoma. Fifty-two-years-old female with a medical history significant only for HTN was admitted to the hospital with bilateral lower extremity edema and dyspnea. Two-dimensional echo demonstrated a right atrial thrombus, extending into the IVC. On subsequent CT and MRI, a 15 cm mass was noted that began in the right atrium and extended into the IVC, with continuation below the renal veins to above the level of the confluence of the common iliac veins. The patient underwent a complete resection of the mass, replacement of the IVC with Dacron graft, total hepatectomy and bilateral nephrectomy, with liver and kidney autotransplantation. Pathology was consistent with a high grade spindle cell sarcoma of vena cava origin. Patient was readmitted approximately 4 weeks postoperatively to begin adjuvant chemotherapy. This case represents a zone I-III IVC leiomyosarcoma treated with surgical R0 resection. This included a hepatectomy, bilateral nephrectomy, and hepatic and left renal autotransplantation. These complex tumors should be treated with surgical resection, and require a multidisciplinary approach.

Prevention of siderophore- mediated gut-derived sepsis due to P. aeruginosa can be achieved without iron provision by maintaining local phosphate abundance: role of pH.

BACKGROUND: During extreme physiological stress, the intestinal tract can be transformed into a harsh environment characterized by regio- spatial alterations in oxygen, pH, and phosphate concentration. When the human intestine is exposed to extreme medical interventions, the normal flora becomes replaced by pathogenic species whose virulence can be triggered by various physico-chemical cues leading to lethal sepsis. We previously demonstrated that phosphate depletion develops in the mouse intestine following surgical injury and triggers intestinal P. aeruginosa to express a lethal phenotype that can be prevented by oral phosphate ([Pi]) supplementation. RESULTS: In this study we examined the role of pH in the protective effect of [Pi] supplementation as it has been shown to be increased in the distal gut following surgical injury. Surgically injured mice drinking 25 mM [Pi] at pH 7.5 and intestinally inoculated with P. aeruginosa had increased mortality compared to mice drinking 25 mM [Pi] at pH 6.0 (p < 0.05). This finding was confirmed in C. elegans. Transcriptional analysis of P. aeruginosa demonstrated enhanced expression of various genes involved in media alkalization at pH 6.0 and a global increase in the expression of all iron-related genes at pH 7.5. Maintaining the pH at 6.0 via phosphate supplementation led to significant attenuation of iron-related genes as demonstrated by microarray and confirmed by QRT-PCR analyses. CONCLUSION: Taken together, these data demonstrate that increase in pH in distal intestine of physiologically stressed host colonized by P. aeruginosa can lead to the expression of siderophore-related virulence in bacteria that can be prevented without providing iron by maintaining local phosphate abundance at pH 6.0. This finding is particularly important as provision of exogenous iron has been shown to have untoward effects when administered to critically ill and septic patients. Given that phosphate, pH, and iron are near universal cues that dictate the virulence status of a broad range of microorganisms relevant to serious gut origin infection and sepsis in critically ill patients, the maintenance of phosphate and pH at appropriate physiologic levels to prevent virulence activation in a site specific manner can be considered as a novel anti-infective therapy in at risk patients.

Structure-function aspects of PstS in multi-drug-resistant Pseudomonas aeruginosa.

The increasing prevalence of multi-drug-resistant (MDR) strains of Pseudomonas aeruginosa among critically ill humans is of significant concern. In the current study, we show that MDR clinical isolates of P. aeruginosa representing three distinct genotypes that display high virulence against intestinal epithelial cells, form novel appendage-like structures on their cell surfaces. These appendages contain PstS, an extracellular phosphate binding protein. Using anti-PstS antibodies, we determined that the PstS-rich appendages in MDR strains are involved in adherence to and disruption of the integrity of cultured intestinal epithelial cell monolayers. The outer surface-expressed PstS protein was also identified to be present in P. aeruginosa MPAO1, although to a lesser degree, and its role in conferring an adhesive and barrier disruptive phenotype against intestinal epithelial cells was confirmed using an isogenic DeltaPstS mutant. Formation of the PstS rich appendages was induced during phosphate limitation and completely suppressed in phosphate-rich media. Injection of MDR strains directly into the intestinal tract of surgically injured mice, a known model of phosphate limitation, caused high mortality rates (60%-100%). Repletion of intestinal phosphate in this model completely prevented mortality. Finally, significantly less outer surface PstS was observed in the MPAO1 mutant DeltaHxcR thus establishing a role for the alternative type II secretion system Hxc in outer surface PstS expression. Gene expression analysis performed by RT-PCR confirmed this finding and further demonstrated abundant expression of pstS analogous to pa5369, pstS analogous to pa0688/pa14-55410, and hxcX in MDR strains. Taken together, these studies provide evidence that outer surface PstS expression confers a highly virulent phenotype of MDR isolates against the intestinal epithelium that alters their adhesive and barrier disrupting properties against the intestinal epithelium.