Clinical Transplantation最新文献

Background: Endomyocardial biopsies (EMB) remain the reference standard for detection of acute rejection in heart transplant (HTx) patients. Recent studies evaluating novel noninvasive tests have sparked a renewed discussion in the HTx community about revising acute rejection surveillance policies. However, patient and provider perspectives remain underexplored. This single-center study examined both HTx patient and provider perspectives on replacing EMBs earlier with noninvasive blood tests.

Methods: We performed semi-structured interviews with 28 HTx patients to explore their perspectives on replacement of EMBs with donor-derived cell-free DNA (dd-cfDNA) early post-HTx. We subsequently conducted a survey of 118 HTx patients using self-administered online questionnaires. We also performed semi-structured interviews with 18 HTx providers to explore their perspectives. Thematic analysis was performed on interview and open-ended survey responses using deductive and inductive approaches. Patient quantitative survey responses were analyzed with descriptive statistics.

Results: Our study identified three key themes: patient anxiety related to EMBs, importance of patient-provider communication, and strong interpersonal trust in providers by HTx patients. Although 78.4% of patients experienced EMB-related anxiety, they prioritized testing accuracy to ensure "the health of their new heart." Consequently, patients favored the most accurate testing protocol and trusted providers to make this decision (91.1%). HTx providers raised concerns about the accuracy and safety of noninvasive surveillance testing for high-risk patients.

Conclusion: HTx patients trusted their providers to determine the most accurate acute rejection surveillance policy. Additionally, our study provides important patient-centered priorities to guide the implementation of early noninvasive testing into clinical practice.

Trial registration: ClinicalTrials.gov identifier: NCT06414603.

Background: As COVID-19 becomes endemic, evaluating COVID-19+ donors for heart transplantation (HT) remains important. We assessed long-term outcomes using national data and propensity-matched analysis.

Methods: All adults (>18 years) undergoing HT between 4/2020 and 9/2024 were identified in the UNOS database. They were stratified into COVID-19+ versus -, defined by either a positive nucleic acid or antigen test within 7 days of HT. Groups were then 3:1 nearest propensity score matched. Survival was estimated by the Kaplan-Meier method. Mortality risk was assessed using Cox regression models.

Results: A total of 879 recipients of COVID-19- hearts were matched with 293 recipients of COVID-19+ hearts. We found no significant differences in 3-year landmark survival between cohorts (p = 0.23). Rates of acute rejection (p = 0.15), length of hospital stay (LOS) (p > 0.9), and postoperative stroke (p = 0.53) did not differ significantly between groups. However, dialysis (17% vs. 12%, p = 0.04) and primary graft dysfunction rates at 24-h post-HT were significantly higher in COVID-19+ heart recipients (5.5% vs. 1.8%, p = 0.01). Donor COVID-19+ status was not significantly associated with mortality risk (HR 1.01, p = 0.66). COVID-19+ donor HTs in recent years (2022-2024) were associated with decreased mortality risk (HR 0.82, p = 0.02), rates of acute rejection (p < 0.001), LOS (p = 0.01), and dialysis (18% vs. 8.9%, p = 0.03).

Conclusions: COVID-19+ hearts demonstrate adequate long-term outcomes, particularly in recent years. Future studies should assess the impact of donor vaccination to optimize survival benefits.

Background: Unplanned reintubation after combined heart-lung transplantation (HLT) significantly affects morbidity and mortality, yet national data are limited. We evaluated the incidence, predictors, timing, and outcomes associated with reintubation after HLT.

Methods: We retrospectively reviewed adults undergoing primary HLT in the UNOS registry from January 2004 to September 2024. Patients were stratified by reintubation status (defined as re-established mechanical ventilation (MV) after initial extubation). Propensity matching (1:1) balanced recipient and donor characteristics. Multivariable logistic regression models identified independent risk factors.

Results: Among 609 adult HLT recipients, 165 (27.1%) required postoperative reintubation. After 1:1 propensity score matching, 146 patients who were reintubated were compared with 146 patients who were successfully extubated. Reintubation was associated with significantly higher early mortality: 30-day (8.2% vs. 3.4%; p = 0.023), 90-day (11.6% vs. 5.5%; p = 0.030), and 6-month (15.1% vs. 8.2%; p = 0.028) mortality rates were all higher in the reintubated cohort, although long-term survival at 1, 3, and 5 years was similar between groups. Early graft failure was more frequent among reintubated patients at 30 days (5.5% vs. 0.7%; p = 0.018) and 90 days (6.2% vs. 1.4%; p = 0.031), with no significant differences thereafter. Reintubated recipients also demonstrated worse functional recovery at discharge (moderate-to-severe limitation: p = 0.012), longer duration of mechanical ventilation (extubated ≤48 h: 20.6% vs. 41.8%; p = 0.003), markedly prolonged hospital stays (73.4 ± 68.8 vs. 37.7 ± 35.3 days; p < 0.0001), and higher rates of stroke (5.5% vs. 3.4%; p = 0.035) and dialysis (37.7% vs. 20.6%; p = 0.001).

Conclusions: Reintubation after HLT significantly increases morbidity and mortality. Identified predictors provide actionable targets for enhanced perioperative airway management.

Background: Efforts to identify barriers and improve access to kidney transplantation in the United States are limited by a lack of population-level data on early steps in the transplant evaluation process.

Methods: We used a rule-based natural language processing (NLP) approach with clinical notes in the US Veterans Affairs Healthcare System (VA) electronic health record (EHR) and linkage with the United States Renal Data System registry to characterize sequential steps in the kidney transplant evaluation process. Adults with advanced kidney disease (estimated glomerular filtration rate ≤20 mL/min/1.73m²) from 1/1/2012-12/31/2019 who were receiving care within the VA were followed through 12/31/2021.

Results: Among 45,174 cohort members, the median age was 71 (IQR 64, 80) years, and 97.2% were men. There was documentation of kidney transplant being mentioned as a treatment option for 46.3% of cohort members, 28.2% engaged in some type of evaluation for transplant, and 8.4% were referred to and 5.4% evaluated at a VA kidney transplant center. 6.9% of cohort members were added to the national deceased donor waitlist and 3.1% received a kidney transplant. Compared with events identified through EHR chart search and manual review by two clinicians, NLP identified events within 90 days with a precision of 0.82-0.94 and recall of 0.56-0.89.

Conclusion: These results illuminate the substantial proportion of patients who engage in early steps in the kidney transplant evaluation process. The work also demonstrates that NLP can accurately identify these key steps in the process as documented in patients' EHRs.

Background: Uncontrolled donors after circulatory death (uDCDs) are recognized as a potential donor pool. No data are so far available on liver biopsy findings in uDCDs. We aimed at assessing liver biopsy findings in uDCDs consecutively admitted to our Center from 2019 to 2023.

Methods: Twenty nine utilized uDCD consecutively admitted at our Center from 2019 to 2023 were included. Liver biopsies were performed during organ procurement in all uDCDs.

Results: The median time from cardiac arrest to normothermic regional perfusion (NRP) run was 144 min, while the median NRP duration was 6 h. The liver was retrieved but not transplanted in 12 donors (12/29, 41%) and transplanted in 10 donors (10/29, 35%). In 7 uDCDs, livers were not retrieved (24%). Ishak grading score 1-2 was observed in most biopsies (21/29, 72%). The incidence of microsteatosis <50% and macrosteatosis <30% was prevalent in our series (24/29, 82% and 22/29, 76%). Lobular infiltration was found in most biopsies (15/24, 63%), while hepatocellular focal necrosis was documented in the 45% (11/24). Severe IRI was found in a small percentage of uDCDs (4/24, 16%).

Conclusion: In our series, liver biopsy in uDCDs may provide clinicians with two different kinds of information. The first one may be mainly related to comorbidities and chronic damages, as indicated by the presence (and percentages) of micro/macrosteatosis and Ishak grading/score. The second one might provide insights into the ischemic-reperfusion injury of the liver, that is it might be related to the uDCD process itself.

Background: Posttransplant opioid dependence has been linked to adverse outcomes in solid organ transplantation, but its impact on pancreas transplantation is underexplored.

Methods: This retrospective study analyzed 193 PTA/PAK recipients from Asan Medical Center (AMC) (2010-2022) and externally validated results in 77 recipients from Pusan National University Yangsan Hospital (PNUYH) (2015-2022). Posttransplant opioid dependence was defined as ≥ 10 opioid prescriptions between 3 and 12 months posttransplant. Logistic regression and three ML algorithms (CatBoost, XGBoost, and LightGBM) were used to identify risk factors and predict 5-year graft survival.

Results: Posttransplant opioid dependence (OR 2.87, p = 0.005) independently predicted 5-year graft failure, along with pre-transplant retinopathy, bladder drainage, and lower BMI. ML models showed favorable internal AUROC (0.695-0.719) and moderate external AUROC (0.649-0.671). Opioid dependence consistently ranked among top predictive features across models.

Conclusions: Posttransplant opioid dependence is a significant predictor of graft failure after pancreas transplantation. Incorporating this variable into ML models may enhance risk stratification and candidate selection.

Background: The UK Kidney Allocation Scheme (KAS) prioritizes organ allocation based on HLA mismatches, assigning the greatest weight to HLA-DR compatibility. However, the clinical relevance of this approach across different ethnicities in the era of modern immunosuppression remains uncertain.

Methods: We conducted a retrospective cohort study of 25 094 adult deceased donor kidney transplants in the United Kingdom between 2008 and 2020. Using competing risk Cox regression, we evaluated the impact of individual HLA locus mismatches and grouped mismatch levels (as defined by UK-KAS) on graft survival. Subgroup analyses by ethnicity were performed, and the relationship between HLA mismatches and acute rejection was assessed using logistic regression.

Results: A single HLA-DR mismatch was significantly associated with graft failure (SHR 1.119, 95% CI 1.035-1.211, p = 0.005), while mismatches at the A, B, and DQ loci were not. In subgroup analyses, HLA-DR mismatching was predictive of graft failure in Asian recipients but not in Black recipients. Black patients also exhibited higher rates of mismatching at all loci. DQ mismatches were associated with early acute rejection but did not predict long-term graft failure. Ten-year graft survival was 13% less with one HLA DR mismatch, and 17% less with 2 HLA DR mismatch, in comparison to zero DR mismatch. The four-level HLA mismatch grouping used by UK-KAS stratified risk incrementally, with levels 3 and 4 associated with 13% and 19% higher failure risk, respectively.

Conclusions: HLA-DR matching improves graft survival overall but offers limited benefit in Black recipients, likely due to low-resolution typing inadequately capturing immunological compatibility across ethnic lines. The current UK-KAS scoring system may inadvertently disadvantage ethnic minorities by delaying transplantation for matches that confer minimal benefit. Our findings support incorporating ethnicity-specific considerations into kidney allocation policy to promote equity and optimize outcomes.