Transplantation Direct最新文献

Post-transplant lymphoproliferative disorders (PTLDs) remain a feared complication of transplantation, with significant morbidity and mortality. The oncogenic Epstein-Barr virus (EBV) is a key pathogenic driver in 50%-80% of cases. Numerous prognostic indices, comprising multiple clinical, epidemiological and tumor characteristics, including EBV tumor positivity, do not consistently associate with worse patient survival, suggesting a potential role for EBV genome variants in determining outcome. However, the precision medicine tools for determining if a viral genome variant is pathogenic are very limited compared with human genome variants. Further, targeted studies have not implicated a specific viral etiological agent in EBV-negative PTLD. Using novel cutting-edge technologies, we are extracting viral nucleic acids from formalin-fixed, paraffin-embedded archived, or frozen PTLD tissues or plasma, to test for all vertebrate viruses simultaneously in an unbiased fashion, using metagenomic shotgun sequencing (MSS). We are collecting such samples from multiple transplant centers to address the following specific aims and close the following knowledge gaps: (1) Validate our novel observation that PTLD tissue positivity by MSS for anellovirus (and confirmed by PCR) serves as a biomarker for higher transplant recipient mortality after the diagnosis of PTLD; (2) determine the role of other oncogenic viruses in EBV-negative PTLD by unbiased MSS of multiple viral groupings, confirmed by other techniques; and (3) develop the necessary computational, algorithmic and software analytic tools required to determine association of EBV genome variants with worse presentations or outcomes in PTLD. Study completion will contribute to better patient care and may provide avenues for novel therapies.

Background: There are limited data about the risk factors for weight changes and the association of significant weight changes with graft and metabolic outcomes after simultaneous pancreas and kidney (SPK) transplantation.

Methods: We included all SPK recipients with both allografts functioning for at least 6 mo post-transplant and categorized them based on the weight changes from baseline to 6 mo post-transplant. We analyzed risk factors for significant weight gain (SWG) and significant weight loss (SWL) over 6 mo post-transplant, as well as outcomes including pancreas uncensored graft failure, pancreas death-censored graft failure (DCGF), composite pancreas graft outcomes of DCGF, use of an antidiabetic agent, or hemoglobin A1C >6.5%, and kidney DCGF.

Results: Of 280 SPK recipients, 153 (55%) experienced no significant weight change, 57 (20%) SWG, and 70 (25%) SWL. At 6 mo post-transplant, mean weight changes were 1.2% gain in the no significant weight change group, 13.4% gain in SWG, and 9.6% loss in the SWL groups. In multivariate analysis, the only factor associated with decreased risk for weight gain was older recipient age (aOR, 0.97; 95% confidence intervals, 0.95-0.99). Importantly, SWG or SWL were not associated with pancreas graft failure, P-DCGF, or K-DCGF. Interestingly in the adjusted model, SWG at 6 mo was associated with a lower risk for composite outcomes (HR, 0.35; 95% confidence intervals, 0.14-0.85).

Conclusions: Forty-five percent of SPK recipients had significant weight changes by 6 mo post-transplant, but only 20% exhibited SWG. Likely because of proper management, weight changes were not associated with poor outcomes post-SPK transplant.

Background: Liver transplantation (LT) outcomes are influenced by donor-recipient size mismatch. This study re-evaluated the impact on graft size discrepancies on survival outcomes.

Methods: Data from 53 389 adult LT recipients from the United Network for Organ Sharing database (2013-2022) were reviewed. The study population was divided by the body surface area index (BSAi), defined as the ratio of donor body surface area (BSA) to recipient BSA, into small-for-size (BSAi < 0.78), normal-for-size (BSAi 0.78-1.24), and large-for-size (BSAi > 1.24) grafts in deceased donor LT (SFSD, NFSD, and LFSD). Multivariate Cox regression and Kaplan-Meier survival analyses were conducted.

Results: The frequency of size mismatch in deceased donor LT increased over the past 10 y. SFSD had significantly worse 90-d graft survival (P < 0.01), and LFSD had inferior 1-y graft survival among 90-d survivors (P = 0.01). SFSD was hazardous within 90 d post-LT because of vascular complications. Beyond 1 y, graft size did not affect graft survival. LFSD risk within the first year was mitigated with lower model for end-stage liver disease (MELD) 3.0 scores (<35) or shorter cold ischemia time (<8 h).

Conclusions: The negative impacts on donor-recipient size mismatch on survival outcomes are confined to the first year post-LT. SFSD is associated with a slight decrease in 90-d survival rates. LFSD should be utilized more frequently by minimizing cold ischemia time to <8 h, particularly in patients with MELD 3.0 scores below 35. These findings could improve donor-recipient matching and enhance LT outcomes.

Background: Recurrent glomerulonephritis (GN) is an important cause of allograft loss after transplantation when GN is the primary cause of kidney failure. Retransplantation after allograft loss from recurrent disease requires careful consideration. We aimed to determine the probability of relisting and the risk of allograft loss after retransplantation in recipients with prior allograft loss from recurrent GN.

Methods: Using data from the Australia and New Zealand Dialysis and Transplant Registry and multivariable Cox modeling, we compared the probability of waitlisting and allograft loss after second transplantation between those with and without prior allograft loss from recurrent disease.

Results: Of 3276 patients who received a second kidney transplant, 179 (5%) lost their first allograft from recurrent GN. Between 2006 and 2021, 1524 patients with failed first allografts (6% with recurrent GN, 45% with primary GN but no disease recurrence) were relisted for transplantation. Compared with patients without primary GN, the adjusted hazard ratios (95% confidence intervals) for relisting in patients with primary GN, with and without disease recurrence, were 1.09 (0.88-1.34) and 1.16 (1.05-1.29), respectively. The respective adjusted hazard ratios for allograft loss after repeat transplantation were 0.77 (0.59-1) and 1.02 (0.9-1.16). Of the 81 patients who received a second allograft after losing their first allograft to GN recurrence, 18 patients (22%) also lost their second allograft because of recurrent GN.

Conclusions: Patients with prior allograft loss from GN recurrence were not disadvantaged, with comparable waitlist potential and allograft outcome after repeat transplantation. However, >20% of those with prior allograft loss from disease recurrence also lost their second allografts from recurrent disease.

Background: Preimplantation biopsy combines measurements of injury into a composite index to inform organ acceptance. The uncertainty in these measurements remains poorly characterized, raising concerns variability may contribute to inappropriate clinical decisions.

Methods: We adopted a metrological approach to evaluate biopsy score reliability. Variability was assessed by performing repeat biopsies (n = 293) on discarded allografts (n = 16) using 3 methods (core, punch, and wedge). Uncertainty was quantified using a bootstrapping analysis. Observer effects were controlled by semi-blinded scoring, and the findings were validated by comparison with standard glass evaluation.

Results: The surgical method strongly determined the size (core biopsy area 9.04 mm², wedge 37.9 mm²) and, therefore, yield (glomerular yield r = 0.94, arterial r = 0.62) of each biopsy. Core biopsies yielded inadequate slides most frequently. Repeat biopsy of the same kidney led to marked variation in biopsy scores. In 10 of 16 cases, scores were contradictory, crossing at least 1 decision boundary (ie, to transplant or to discard). Bootstrapping demonstrated significant uncertainty associated with single-slide assessment; however, scores were similar for paired kidneys from the same donor.

Conclusions: Our investigation highlights the risks of relying on single-slide assessment to quantify organ injury. Biopsy evaluation is subject to uncertainty, meaning each slide is better conceptualized as providing an estimate of the kidney's condition rather than a definitive result. Pooling multiple assessments could improve the reliability of biopsy analysis, enhancing confidence. Where histological quantification is necessary, clinicians should seek to develop new protocols using more tissue and consider automated methods to assist pathologists in delivering analysis within clinical time frames.

Background: The purpose of this study was to explore the experience of family members of potential organ donors in the intensive care unit following the change to deemed consent legislation in Nova Scotia.

Methods: This was a qualitative study with semistructured, in-depth interviews with 17 family members who were asked to make an organ donation decision on behalf of patients admitted to the intensive care unit in Nova Scotia. We analyzed themes using a descriptive approach. Participants were recruited from the organ donation organization in Nova Scotia, Canada.

Results: Participant awareness and knowledge of the Human Organ and Tissue Donation Act legislation varied from individuals having no awareness and knowledge of the bill to those who had awareness and optimism that the legislation would be beneficial for increasing organ donation rates in the province. Other themes emerging from the interviews included (1) COVID context, (2) quality of healthcare professional care, (3) family support, and (4) barriers to donation (waiting, consent questionnaire, and patient transfers).

Conclusions: The Human Organ and Tissue Donation Act legislation included enhanced support, which was viewed positively by family members. There is a need for continued evaluation as most participants felt it was too early to see the tangible impacts of the newly implemented legislation.

Background: Since 1998, the Swiss Organ Living-Donor Health Registry (SOL-DHR) has recorded peri- and postoperative complications of living kidney (LK) donors, as reported by all Swiss transplant centers and has collected follow-up data prospectively.

Methods: We analyzed the early complications of 2379 consecutive individuals who donated a kidney between January 1998 and June 2022 and assessed their health-related quality of life (HRQoL) 1 y after donation.

Results: In total, 447 early complications in 404/2379 LK donors (17.0%) were reported to the SOL-DHR. The frequency of donors with major complications (ie, Dindo-Clavien classification 3/4) was 2.4%. In total, 31 donors needed reoperation, and in 13/31 (42%), donors reoperation was necessary because of bleeding complications. Independent risk factors for major early complications were older donor age (P = 0.005) and type of surgical approach (ie, the laparoscopic retroperitoneal compared with laparoscopic transabdominal surgery; P = 0.01), but not sex. We observed a U-shaped association of body mass index, where very low/high body mass indexes had higher odds of major early complications, without reaching statistical significance. Although HRQoL was affected by kidney donation, 96.5% of donors indicated that they would donate their kidney again. The only independent risk factor for low HRQoL based on mental health scores was worsening EB after living kidney donation (P < 0.0001).

Conclusions: Overall, living kidney donation is a safe procedure, however, donor age and type of surgical approach affect the risk of complications. A decline in emotional bonding with the recipient after donation may worsen the quality of life of the donor.

Background: The global surge in aging has intensified debates on liver transplantation (LT) for candidates aged 75 y and older, given the prevalent donor scarcity. This study examined both the survival benefits and organ utility of LT for this age group.

Methods: A total of 178 469 adult LT candidates from the United Network for Organ Sharing database (2003-2022) were analyzed, with 112 266 undergoing LT. Post-LT survival outcomes and waitlist dropout rates were monitored across varying age brackets. Multivariable Cox regression analysis determined prognostic indicators. The 5-y survival benefit was assessed by comparing LT recipients to waitlist candidates using hazard ratios. Organ utility was evaluated through a simulation model across various donor classifications.

Results: Among candidates aged 75 y and older, 343 received LT. The 90-d graft and patient survival rates for these patients were comparable with those in other age categories; however, differences emerged at 1 and 3 y. Age of 75 y or older was identified as a significant negative prognostic indicator for 3-y graft survival (hazard ratio: 1.72 [1.20-2.42], P < 0.01). Dropout rates for the 75 y and older age category were 12.0%, 24.1%, and 35.1% at 90 d, 1 y, and 3 y, respectively. The survival benefit of LT for the 75 y and older cohort was clear when comparing outcomes between LT recipients and those on waitlists. However, organ utility considerations did not favor allocating livers to this age group, regardless of donor type. Comparing 3-y patient survival between LT using donors aged 60 y and younger and older than 60 y showed no significant difference (P = 0.50) in the 75 y or older cohort.

Conclusions: Although LT offers survival benefits to individuals aged 75 y and older, the system may need rethinking to optimize the use of scarce donor livers, perhaps by matching older donors with older recipients.

Background: The impact of induction type or high-risk viral discordance on older kidney transplant recipients is unclear. Herein, we analyzed the association between induction type, viral discordance, and outcomes for older recipients.

Methods: We analyzed the Scientific Registry of Transplant Recipients standard analysis file for all primary kidney transplant recipients older than 55 y who were transplanted between 2005 and 2022. All transplants were crossmatch negative and ABO-compatible. Recipients were discharged on tacrolimus and mycophenolate ± steroids. Recipients were categorized into 3 groups by induction received: rabbit antithymocyte globulin (r-ATG; N = 51 079), interleukin-2 receptor antagonist (IL-2RA; N = 22 752), and alemtuzumab (N = 13 465). Kaplan-Meier curves were generated for recipient and graft survival, and follow-up was censored at 10 y. Mixed-effect Cox proportional hazard models examined the association between induction type, high-risk viral discordance, and outcomes of interest. Models were adjusted for pertinent recipient and donor characteristics.

Results: Induction type did not predict recipient survival in the multivariable model, whereas Epstein-Barr virus high-risk discordance predicted 14% higher mortality (1.14 [1.07-1.21], P < 0.01). In the multivariable model for death-censored graft survival, alemtuzumab, but not IL-2RA, was associated with an increased risk of graft loss (1.18 [1.06-1.29], P < 0.01) compared with r-ATG. High-risk cytomegalovirus discordance predicted 10% lower death-censored graft survival (1.10 [1.01-1.19], P < 0.02). Live donor and preemptive transplantation were favorable predictors of survival.

Conclusions: In this large cohort of older transplant recipients, alemtuzumab, but not IL-2RA, induction was associated with an increased risk of graft loss compared with r-ATG. Cytomegalovirus and Epstein-Barr virus high-risk viral discordance portended poor graft and recipient survival, respectively.

Liver transplantation (LT) in patients with significant portopulmonary hypertension (PoPH) is associated with an increased risk of several complications, including graft failure. Graft loss is one of the major reasons. Living donor LT (LDLT) is not routinely performed in the United States in this patient population. In addition, ethical considerations often preclude donation from healthy donors in the setting of a procedure associated with an elevated risk of recipient morbidity and mortality. However, LDLT allows LT to be performed electively, using a superior graft with an improved probability of a good outcome. The key to success in managing these patients is establishing a multidisciplinary team that follows an institutional protocol with clear evaluation and management criteria. These criteria include screening and early diagnosis as well as treatment of PoPH with the goal of optimizing pulmonary arterial hemodynamics and maintaining right ventricular function. Any protocol should include admitting the patient to the hospital a day before surgery for placement of a pulmonary artery catheter to measure and derive relevant hemodynamic variables. A multidisciplinary team should determine the fitness for a transplant a after a careful review of the most up-to-date clinical information. Finally, the team prescribes and executes a plan for optimization and safe perioperative management of the patient. In this report, we discuss our approach to the perioperative management of a patient with significant PoPH who safely underwent LDLT with an excellent postoperative outcome.