Outcomes In Transplant Recipients Research Articles

Changes in waiting time, need for mechanical circulatory support and outcomes in paediatric heart transplant recipients.

Heart transplantation is a well-established treatment for end-stage heart failure in paediatric patients, demonstrating excellent long-term outcomes. This retrospective study analyses 35years of data on 244 paediatric recipients (<18years) at a single institution from 1986 to 2022. The analysis explores changes in diagnoses, survival, waiting times and mechanical circulatory support (MCS) over three decades (1991-2000, 2001-2010 and 2011-2020). Survival outcomes significantly improved over the study period, with 1-year survival rates increasing from 79.3% (1991-2000) to 92.3% (2011-2020, P=0.041). The median overall survival was 18.0years, and median conditional survival to 1year post-transplant was 20.9years. Survival differences were noted among age groups, with infants under 1year of age experiencing higher early mortality, and adolescents (aged 11-17years) facing increased long-term risks, possibly linked to adult donor characteristics. Waiting times for heart transplantation increased, especially for younger age groups (0-5 and 6-10years), reflecting the growing demand for donor organs. The use of MCS, including ventricular assist devices (VAD), surged, with 67% of recipients in the most recent decade receiving pre-transplant VAD support. Importantly, despite prolonged waiting times and increased VAD use, overall survival continued to be favourable. Early and long-term results after paediatric heart transplantation have been continuously improving over the past decades. Despite an increased demand for donor organs and the growing reliance on VAD as bridge to transplantation, post-transplantation survival is not compromised.

Outcomes of kidney transplant recipients exposed to Chagas disease under Benznidazole prophylaxis. A single center 10-year experience.

Chagas disease (ChD) is endemic in many parts of the world and can be transmitted through organ transplantation or reactivated by immunosuppression. Organs from infected donors are occasionally used for transplantation, and the best way of managing the recipients remains a subject of debate. We present a single-center cohort study describing a 10-year experience of kidney transplantation in patients at risk of donor-derived ChD and or reactivation. Patients received prophylactic treatment with Benznidazole and were monitored for transmission or reactivation. Monitoring included assessing direct parasitemia, serology, and polymerase chain reaction (PCR). Fifty-seven kidney transplant recipients (KTRs) were enrolled in the study. Forty-four patients (77.2%) were at risk of primary ChD infection, nine patients (15.8%) were at risk of disease reactivation, and four patients (7.0%) were at risk of both. All patients received Benznidazole prophylaxis, starting on the first day after transplantation. Parasitemia was assessed in 51 patients (89.5%), serology also in 51 patients (89.5%), and PCR in 40 patients (70.2%). None of the patients exhibited clinically or laboratory-detectable signs of disease. A single patient experienced a significant side effect, a cutaneous rash with intense pruritus. At 1-year post-transplantation, the patient and graft survival rates were 96.5% and 93%, respectively. In this study, no donor-derived or reactivation of Trypanosoma cruzi infection occurred in KTRs receiving Benznidazole prophylaxis.

Vibration-Controlled Transient Elastography–Based Parameters Predict Clinical Outcomes in Liver Transplant Recipients

Vibration-controlled transient elastography (VCTE) is used in clinical practice to risk-stratify liver transplant (LT) recipients; however, there are currently little data demonstrating the relationship between VCTE and clinical outcomes. A total of 362 adult LT recipients with successful VCTE examination between 2015 and 2022 were included. Presence of advanced fibrosis was defined as liver stiffness measurement (LSM) ≥10.5 kPa and hepatic steatosis as controlled attenuation parameter (CAP) ≥270 dB/m. The outcomes of interest included all-cause mortality, myocardial infarction (MI), and graft cirrhosis using cumulative incidence analysis that accounted for the competing risks of these outcomes. The LSM was elevated in 64 (18%) and CAP in 163 (45%) LT recipients. The baseline LSM values were similar in patients with elevated vs normal CAP values. After a median follow-up of 65 (interquartile range, 20-140) months from LT to baseline VCTE, 66 (18%) patients died, 12 (3%) developed graft cirrhosis, and 18 (5%) experienced an MI. Baseline high LSM was independently associated with all-cause mortality (hazard ratio [HR], 1.97; 95% confidence interval [CI], 1.11-3.50; P= .02) and new onset cirrhosis (HR, 6.74; 95% CI, 2.08-21.79; P < .01). A higher CAP value was significantly and independently associated with increased risk of experiencing a MI over study follow-up (HR, 4.14; 95% CI, 1.29-13.27; P= .017). The VCTE-based parameters are associated with clinical outcomes and offer the potential to be incorporated into clinical risk-stratification strategies to improve outcomes among LT recipients.

Efficacy and safety of COVID-19 vaccination in solid organ transplant recipients: A systematic review and network meta-analysis

The impact of COVID-19 vaccination on clinical outcomes in solid organ transplant (SOT) recipients remains unclear. This systematic review and network meta-analysis sought to assess the efficacy and safety of COVID-19 vaccination in SOT recipients. We searched 6 databases from inception to March 1, 2024 for randomized controlled trials (RCTs) and observational studies evaluating different COVID-19 vaccination strategies in SOT recipients. Based on patient-important outcomes, we performed frequentist random-effects pairwise meta-analyses and network meta-analyses, separating RCTs and nonrandomized evidence, and used the Grading of Recommendation, Assessment, Development, and Evaluation approach to assess our certainty in the evidence. We included 6 RCTs (N = 814) and 43 observational studies (N = 125 199). Overall, there is a paucity of randomized evidence evaluating COVID-19 vaccines in SOT recipients. The nonrandomized evidence evaluating COVID-19 vaccination strategies patient-important outcomes, including COVID-19 infection, mortality, hospitalization, ICU admission, and rejection, demonstrated low to very low certainty due to the included studies’ risk of bias. Throughout the COVID-19 pandemic, clinicians and SOT recipients worked with minimal, very low-quality evidence in relation to COVID-19 vaccines in this population. In the instance of future public health emergencies, clinicians and researchers should collaborate closely with patient partners to ensure there is sufficient evidence in the transplant population on patient-important outcomes.

Recent Insights in Noninvasive Diagnostic for the Assessment of Kidney and Cardiovascular Outcome in Kidney Transplant Recipients.

Kidney transplantation improves quality of life and prolongs survival of patients with end-stage kidney disease. However, kidney transplant recipients present a higher risk for cardiovascular events compared to the general population. Risk assessment for graft failure as well as cardiovascular events is still based on invasive procedures. Biomarkers in blood and urine, but also new diagnostic approaches like genetic or molecular testing, can be useful tools to monitor graft function and to identify patients of high cardiovascular risk. Many biomarkers have been introduced, whereas most of these biomarkers have not been implemented in clinical routine. Here, we discuss recent developments in biomarkers and diagnostic models in kidney transplant recipients. Because many factors impact graft function and cardiovascular risk, it is most likely that no biomarker will meet the highest demands and standards. We advocate to shift focus to the identification of patients benefitting from molecular and genetic testing as well as from analysis of more specific biomarkers instead of finding one biomarker fitting to all patients.

Lung Donation and Transplant Recipient Outcomes at Independent vs Hospital-Based Donor Care Units

Centralizing deceased organ donor management and organ recovery into donor care units (DCUs) may mitigate the critical organ shortage by positively impacting donation and recipient outcomes. To compare donation and lung transplant outcomes between 2 common DCU models: independent (outside of acute-care hospitals) and hospital-based. This is a retrospective cohort study of Organ Procurement and Transplantation Network deceased donor registry and lung transplant recipient files from 21 US donor service areas with an operating DCU. Characteristics and lung donation rates among deceased donors cared for in independent vs hospital-based DCUs were compared. Eligible participants included deceased organ donors (aged 16 years and older) after brain death, who underwent organ recovery procedures between April 26, 2017, and June 30, 2022, and patients who received lung transplants from those donors. Data analysis was conducted from May 2023 to March 2024. Organ recovery in an independent DCU (vs hospital-based DCU). The primary outcome was duration of transplanted lung survival (through December 31, 2023) among recipients of lung(s) transplanted from cohort donors. A Cox proportional hazards model stratified by transplant year and program, adjusting for donor and recipient characteristics was used to compare graft survival. Of 10 856 donors in the starting sample (mean [SD] age, 42.8 [15.2] years; 6625 male [61.0%] and 4231 female [39.0%]), 5149 (primary comparison group) underwent recovery procedures in DCUs including 1466 (28.4%) in 11 hospital-based DCUs and 3683 (71.5%) in 10 independent DCUs. Unadjusted lung donation rates were higher in DCUs than local hospitals, but lower in hospital-based vs independent DCUs (418 donors [28.5%] vs 1233 donors [33.5%]; P < .001). Among 1657 transplant recipients, 1250 (74.5%) received lung(s) from independent DCUs. Median (range) duration of follow-up after transplant was 734 (0-2292) days. Grafts recovered from independent DCUs had shorter restricted mean (SE) survival times than grafts from hospital-based DCUs (1548 [27] days vs 1665 [50] days; P = .04). After adjustment, graft failure remained higher among lungs recovered from independent DCUs than hospital-based DCUs (hazard ratio, 1.85; 95% CI, 1.28-2.65). In this retrospective analysis of national donor and transplant recipient data, although lung donation rates were higher from deceased organ donors after brain death cared for in independent DCUs, lungs recovered from donors in hospital-based DCUs survived longer. These findings suggest that further work is necessary to understand which factors (eg, donor transfer, management, or lung evaluation and acceptance practices) differ between DCU models and may contribute to these differences.

Constructing an Intent-to-Treat Score Index to Predict Survival Outcomes in Pediatric Liver Transplant Recipients.

Waitlist and posttransplant outcomes have been widely reported for pediatric liver transplantation. Yet, analyzing these metrics individually fails to provide a holistic perspective for patients and their families. Intent-to-treat (ITT) analysis fills this gap by studying the associations between waitlist outcomes, organ availability, and posttransplant outcomes. Our study aimed to construct a predictive index utilizing ITT analysis for pediatric liver transplant recipients (Pedi-ITT). We performed a retrospective analysis utilizing de-identified data provided by the United Network for Organ Sharing (UNOS) from March 1, 2002, to December 31, 2021. We analyzed data for 12 926 pediatric recipients (age <18). We conducted a univariate and multivariable logistic regression to find the significant predictive factors affecting ITT survival. A scoring index was constructed to stratify outcome risk on the basis of the significant factors identified by regression analysis. Multivariable analysis found the following factors to be significantly associated with death on the waitlist or after transplant: gender, diagnosis, UNOS region, ascites, diabetes mellitus, age at the time of listing, serum sodium at the time of listing, total bilirubin at the time of listing, serum creatinine at the time of listing, INR at the time of listing, history of ventilator use, and history of re-transplantation. Using receiver operator characteristic analysis, the Pedi-ITT index had a c-statistic of 0.79 (95% confidence interval [CI]: 0.76-0.82). The c-statistics of the Model for End-Stage Liver Disease/Pediatric for End-Stage Liver Disease and pediatric version of the Survival Outcomes Following Liver Transplantation score indices were 0.74 (CI: 0.71-0.76) and 0.69 (CI: 0.66-0.72), respectively. The Pedi-ITT index provides an additional prognostic model with moderate predictive power to assess outcomes associated with pediatric liver transplantation. Further analysis should focus on increasing the predictive power of the index.

Effect of Donor Cigarette Smoking in Kidney Transplantation: Re-Evaluation of Long-Term Outcomes.

Cigarette smoking is a common risk factor associated with negative long-term outcomes in kidney transplant recipients. However, whether donor smoking decreases graft longevity or negatively impacts recipient survival after kidney transplantation remains unknown. Therefore, this study aims to investigate the long-term outcome in patients who received a kidney graft from a deceased smoking or non-smoking donor. A total of 580 patients were divided into two groups: patients who received a graft from a smoking donor (n = 276) and those who received a graft from a non-smoking donor (n = 304). Analysis of demographic factors showed that the non-smoking cohort was older, had more extended criteria donors and longer warm ischemia times. The primary composite endpoint of patient and graft survival was better in the smoking donor cohort when analyzed using Kaplan-Meier method but not when controlled for covariates in multivariate analyses. These findings do not support a previously reported negative impact of deceased donor smoking on kidney transplant recipients. Thus, the underlying results should not be interpreted in favor of a positive donor smoking history, but rather remind the transplant community that donor smoking should not be considered as a deciding factor in refusing an otherwise acceptable kidney graft.

Impact of COVID-19 on liver transplant recipients: A nationwide cohort study evaluating hospitalization, transplant rejection, and inpatient mortality.

The coronavirus disease 2019 (COVID-19) pandemic has posed a major public health concern worldwide. Patients with comorbid conditions are at risk of adverse outcomes following COVID-19. Solid organ transplant recipients with concurrent immunosuppression and comorbidities are more susceptible to a severe COVID-19 infection. It could lead to higher rates of inpatient complications and mortality in this patient population. However, studies on COVID-19 outcomes in liver transplant (LT) recipients have yielded inconsistent findings. To evaluate the impact of the COVID-19 pandemic on hospital-related outcomes among LT recipients in the United States. We conducted a retrospective cohort study using the 2019-2020 National Inpatient Sample database. Patients with primary LT hospitalizations and a secondary COVID-19 diagnosis were identified using the International Classification of Diseases, Tenth Revision coding system. The primary outcomes included trends in LT hospitalizations before and during the COVID-19 pandemic. Secondary outcomes included comparative trends in inpatient mortality and transplant rejection in LT recipients. A total of 15720 hospitalized LT recipients were included. Approximately 0.8% of patients had a secondary diagnosis of COVID-19 infection. In both cohorts, the median admission age was 57 years. The linear trends for LT hospitalizations did not differ significantly before and during the pandemic (P = 0.84). The frequency of in-hospital mortality for LT recipients increased from 1.7% to 4.4% between January 2019 and December 2020. Compared to the pre-pandemic period, a higher association was noted between LT recipients and in-hospital mortality during the pandemic, with an odds ratio (OR) of 1.69 [95% confidence interval (CI): 1.55-1.84), P < 0.001]. The frequency of transplant rejections among hospitalized LT recipients increased from 0.2% to 3.6% between January 2019 and December 2020. LT hospitalizations during the COVID-19 pandemic had a higher association with transplant rejection than before the pandemic [OR: 1.53 (95%CI: 1.26-1.85), P < 0.001]. The hospitalization rates for LT recipients were comparable before and during the pandemic. Inpatient mortality and transplant rejection rates for hospitalized LT recipients were increased during the COVID-19 pandemic.

Donor plasma VEGF-A as a biomarker for myocardial injury and primary graft dysfunction after heart transplantation

BackgroundVascular endothelial growth factor (VEGF)-A is an angiogenic and proinflammatory cytokine with profound effects on microvascular permeability and vasodilation. Several processes may induce VEGF-A expression in brain-dead organ donors. However, it remains unclear whether donor VEGF-A is linked to adverse outcomes after heart transplantation. MethodsWe examined plasma VEGF-A levels from 83 heart transplant donors as well as the clinical data of these donors and their respective recipients operated between 2010 and 2016. The donor plasma was analyzed using Luminex-based Multiplex and confirmed with a single-target ELISA. Based on donor VEGF-A plasma levels, the recipients were divided into three equal-sized groups (low VEGF <500 ng/L, n=28; moderate VEGF 500-3000 ng/L, n=28; and high VEGF >3000 ng/L, n=27). Biochemical and clinical parameters of myocardial injury as well as heart transplant and kidney function were followed-up for one year, while rejection episodes, development of cardiac allograft vasculopathy, and mortality were monitored for five years. ResultsBaseline parameters were comparable between the donor groups, except for age, where median ages of 40, 45, and 50 were observed for low, moderate, and high donor plasma VEGF levels groups, respectively, and therefore donor age was included as a confounding factor. High donor plasma VEGF-A levels were associated with pronounced myocardial injury (TnT and TnI), a higher inotrope score, and a higher incidence of primary graft dysfunction in the recipient after heart transplantation. Furthermore, recipients with allografts from donors with high plasma VEGF-A levels had a longer length of stay in the intensive care unit and the hospital, and an increased likelihood for prolonged renal replacement therapy. ConclusionsOur findings suggest that elevated donor plasma VEGF-A levels were associated with adverse outcomes in heart transplant recipients, particularly in terms of myocardial injury, primary graft dysfunction, and long-term renal complications. Donor VEGF-A may serve as a potential biomarker for predicting these adverse outcomes and identifying extended donor criteria.

Exploring Acute Pancreatitis in Kidney Transplant Recipients: A Multicentre Retrospective Cohort Analysis of Incidence, Causes, and Clinical Outcomes.

Background: The aim of this multicentre retrospective study is to determine the incidence, etiology, clinical characteristics, and outcomes of kidney transplant recipients diagnosed and treated for acute pancreatitis. Methods: We analyzed data from kidney transplant recipients who received kidney allografts between October 1973 and December 2023 and were diagnosed and treated for acute pancreatitis. Results: Of 2482 patients who received kidney allografts, 10 (0.4%) (5 male) were diagnosed with acute pancreatitis, with a mean age of 48.6 years. Patients were diagnosed with acute pancreatitis between 3 weeks and 24 years after the transplantation. Possible etiologies included cholecystolithiasis, COVID-19, hypercalcemia, postprocedural, use of cannabis, trimetoprim-sulphometoxasole, statins, sirolimus, tacrolimus and obesity. There was no suspected etiology in two patients. Patients were treated with aggressive hydration, pain alleviation and antibiotics if indicated. Four patients developed complications. Local complications included peripancreatic collections, pseudocyst, and abscesses formation, while systemic complications occurred in the form of Cytomegalovirus (CMV) reactivation and urinary tract infection. All patients survived with preserved kidney allograft function. Conclusions: Acute pancreatitis in kidney transplant recipients is rare. However, it may be linked to significant morbidity and mortality. While symptoms may be nonspecific and brought on by a variety of viral and non-infectious illnesses, as well as adverse effects from immunosuppressive medications, a high degree of awareness is required.

"Long-term effects of center volume on transplant outcomes in adult kidney transplant recipients"

"Long-term effects of center volume on transplant outcomes in adult kidney transplant recipients"

Outcomes of liver transplant recipients with pretransplant malignancies: Insights from a single institution’s experience.

11173 Background: Increasing liver transplantation (LT) utilization has resulted in more and more patients with a history of a non-hepatobiliary malignancy. Rather than deny such patients a lifesaving therapy the benefits must be weighed against risk of tumor recurrence and de novo malignancies (DNM) post-LT, especially with the immunosuppression required. While data has been presented on outcomes of pre transplant malignancies (PTM) in kidney and heart transplants, LT data is lacking. Our aim is to characterize rates of recurrence, DNM, and overall survival (OS) post-LT at a single, high volume American center. Methods: This retrospective study at Houston Methodist Hospital included patients who underwent LT with known history of PTM. Data was extracted from electronic health records, and descriptive statistics performed. Institutional IRB approval is obtained. Results: Between 01/1999- 12/2022, 1617 LTs were performed at our institute. We identified 261 LT recipients with 297 PTM, including 91 non- and 206 hepatobiliary cancers (See Table). Follow-up period ranged from 1 to 23 years. Post-LT malignancies were observed in 66 patients, 25% of the study population. Tumor recurrences accounted for 44 (17%) cases, and DNM were seen in 22 (8%). The DNMs included skin non-melanoma (n=8 cases), head &amp; neck (3), PTLD (2), prostate (2), renal (1), lung (1), CRC (1), pancreatic (1), gynecologic (2), and poorly differentiated (1). The OS rate at 1-, 5-years (excluding those less than 5 years follow-up and unknown), and at time of last follow-up were 86.6%, 60-65% and 70%, respectively. Patients with post-LT malignancies had lower OS compared to those without (46% vs. 77.7%). Conclusions: To our knowledge, this study is the first to assess post-LT outcomes in patients with PTM. This study of LT recipients with PTM demonstrates post-LT malignancy rates of 25%, including 17% with recurrences and 8% with DNM. The latter is within the previously reported range of 3-14% DNM in the general post-LT population and dominated by skin cancers. Post-LT OS is excellent in these recipients and comparable to all LT patients. However, OS is lower in those with post-LT malignancies, implying a possible role for increased cancer surveillance. Limitations include retrospective design and potential chart bias. Future work in this cohort will focus on immunosuppression effects for this high-risk population. [Table: see text]

Venovenous bypass in liver transplantation: Exploring the benefits, efficacy, and safety.

Venovenous bypass (VVB) is a technique used in liver transplantation (LT) to maintain hemodynamic stability and abdominal organ perfusion and thereby improve patient outcomes. Despite its perceived benefits, VVB utilization has declined globally due to concerns related to heparinization, major bleeding and the need for expertise. Recent advancements, such as percutaneous cannulation techniques and improved extracorporeal technology have improved the safety of VVB in LT. This paper presents a modified VVB circuit with enhanced safety features. Cannulation plays a pivotal role in VVB establishment, with percutaneous methods increasingly favored. Studies demonstrate VVB's efficacy in improving patient outcomes with lower incidence of acute kidney injury and reduced operative time and blood loss, with no added morbidity or mortality. However, its routine use faces challenges, with alternative techniques gaining traction. Our experience highlights VVB's role in various clinical scenarios, including patients with high Model for End-Stage Liver Disease (MELD) scores, challenging surgical anatomy, portal vein thrombosis and pre-existing cardiovascular disease, emphasizing its safety and efficacy. Continued research is needed to optimize VVB techniques and ensure better outcomes for liver transplant recipients.

Rethinking the impact of pretransplant malignancy on eligibility for double lung transplantation (DLT): An analysis of 23,291 recipients.

11180 Background: The outcomes for double lung transplant recipients with a history of pretransplant malignancy (PreTM) have not been extensively studied in a large, multicenter database. Given the rising need for transplants among older patients with a history of cancer and the improving outcomes of DLT, this study aimed to analyze recipient outcomes in the modern era. Methods: This study evaluated the United Network for Organ Sharing (UNOS) registry for adult DLT performed between 2005 and 2023. Patients with a history of previous or multi-organ transplants, and those with donors who had a history of malignancy, were excluded. Propensity-score matching was used to compare patients with or without PreTM. Posttransplant malignancies (PostTM) were classified into cutaneous and non-cutaneous types. The primary outcomes were overall and PostTM-free survival. Results: Of the 23,291 DLT recipients, 1,870 recipients (8.0%) had a history of PreTM, which was classified into twelve types. Patients with PreTM experienced worse overall (HR 1.20 [95% CI 1.12-1.29], p&lt;0.001) and PostTM-free survival (HR 1.32 [95% CI 1.24-1.41], p&lt;0.001). After propensity-score matching for age, sex, and race, the differences in overall survival between the two groups were diminished (HR 1.05 [95% CI 0.97-1.13], p=0.229). Although PostTM-free survival was still worse in the PreTM group, this difference was not observed after excluding cutaneous PostTM (HR 1.06 [95% CI 0.99-1.15], p=0.116). The incidence of PostTM of the same PreTM type among patients with PreTM was 13.5% (253/1870), which was not higher than the incidence of de novo PostTM incidence among patients without PreTM (p=0.633). Conclusions: Patients with PreTM show similar overall survival rates after DLT as those without PreTM, despite a higher incidence of PostTM, mainly cutaneous. Importantly, there is no increased risk of the original cancer type recurring in PreTM patients compared to the risk of de novo malignancy. These findings highlight the necessity for a more nuanced evaluation of transplant candidacy to prevent premature exclusion of PreTM patients from potentially life-saving surgeries. [Table: see text]

Oxalate Nephropathy After Kidney Transplantation: Risk Factors and Outcomes of Two Phenotypes.

Describing risk factors and outcomes in kidney transplant recipients with oxalate nephropathy (ON) may help elucidate the pathogenesis and guide treatment strategies. We used a large single-center database to identify patients with ON and categorized them into delayed graft function with ON (DGF-ON) and late ON. Incidence density sampling was used to select controls. A total of 37 ON cases were diagnosed between 1/2011 and 1/2021. DGF-ON (n=13) was diagnosed in 1.05% of the DGF population. Pancreatic atrophy on imaging (36.4% vs. 2.9%, p=0.002) and gastric bypass history (7.7% vs. 0%; p=0.06) were more common in DGF-ON than with controls with DGF requiring biopsy but without evidence of ON. DGF-ON was not associated with worse graft survival (p=0.98) or death-censored graft survival (p=0.48). Late ON (n=24) was diagnosed after a mean of 78.2 months. Late ON patients were older (mean age 55.1 vs. 48.4 years; p=0.02), more likely to be women (61.7% vs. 37.5%; p=0.03), have gastric bypass history (8.3% vs. 0.8%; p=0.02) and pancreatic atrophy on imaging (38.9% vs. 13.3%; p=0.02). Late ON was associated with an increased risk of graft failure (HR 2.0; p=0.07) and death-censored graft loss (HR 2.5; p=0.10). We describe two phenotypes of ON after kidney transplantation: DGF-ON and late ON. Our study is the first to our knowledge to evaluate DGF-ON with DGF controls without ON. Although limited by small sample size, DGF-ON was not associated with adverse outcomes when compared with controls. Late ON predicted worse allograft outcomes.

Mycophenolate Metabolite Trough Concentrations Are Not Well Correlated With Dosing or Adverse Outcomes in Pediatric Heart Transplant Recipients.

Although mycophenolate metabolite trough concentrations in serum are routinely obtained for pediatric orthotopic heart transplant (OHT) recipients, limited data support this practice. We sought to investigate the relationship of mycophenolic acid (MPA) and MPA glucuronide (MPAG) serum concentrations to dosing and adverse outcomes among pediatric OHT patients. This retrospective study included OHT recipients ages 0 to 21 years who received mycophenolate mofetil (MMF) with MPA and MPAG serum trough concentration monitoring. The primary outcome was the relationship between MPA and MPAG serum concentrations and dosing. Secondary outcomes included the relationship of adverse outcomes to either MPA and MPAG concentrations or dosing. A total of 98 patients with 1287 MPA and MPAG trough serum concentrations (each) were included. The median initial MMF dose was 40.3 mg/kg/day (IQR, 35.12-51.83) and 1164.4 mg/m2/day (IQR, 1080.77-1206.86). There was no correlation between either MPA or MPAG serum concentrations and mg/kg dosing, or mg/m2 dosing. When comparing the adverse effect of bone marrow suppression with no adverse effect, the median MPA serum trough concentration was 2 (IQR, 1.1-3.2) versus 1.6 (IQR, 0.8-2.5), p = 0.003. When comparing the adverse effect of infection with no adverse effect, median MPA serum trough concentration was 0.9 (IQR, 0.49-1.7) versus 1.6 (IQR, 0.8-2.5), p < 0.001. The clinical utility of this finding is of uncertain benefit. There was no association between MPAG serum concentrations and any adverse outcome (p = 0.053). We did not identify a correlation between mycophenolate serum trough concentrations and either adverse outcomes or dosing. Based on these results, we discourage routine monitoring of mycophenolate trough concentrations.

#815 Maternal and fetal outcomes in kidney transplant recipients: a single-center observational study

Abstract Background and Aims Pregnancy poses a high risk for adverse maternal and fetal outcomes in kidney transplant recipients (KTRs), and data on long-term allograft functions compared to healthy population are still limited. Therefore, we aimed to conduct a comparative analysis of maternal and fetal outcomes in KTRs with age-matched non-transplanted controls. Method In this retrospective single-center study, KTRs who experienced at least one pregnancy after transplantation between 1984 and 2016 were evaluated (study group). In order to create an age-matched control group, healthy women who had one pregnancy each and received prenatal care were included. Maternal and fetal outcomes were gestational age, preterm birth, newborn mortality, admittance to neonatal intensive care unit (NICU), Apgar scores, birth weight, and obstetric complications (preeclampsia, peripartum hemorrhage, duration of maternal hospitalization) in all pregnancies, and composite kidney outcome of KTRs which was defined as progression to graft failure necessitating dialysis or re-transplantation or doubling of serum creatinine at the end of follow-up. Results In 53 KTRs, 68 pregnancies occurred. Mean age at birth was 31.6 ± 5.2 for KTRs and 30.5 ± 5.8 for controls (p = 0.288). Preeclampsia (29.4% vs. 2.9%, p &amp;lt; 0.001) and preterm birth (57.4% vs. 32.4%, p = 0.003) were significantly higher in KTRs. KTR pregnancies had lower mean birth weight (2354 ± 814 vs. 2856 ± 729 mg, p = 0.001) and longer durations of maternal hospitalization (3 vs. 2 days, p = 0.001), as well. However, neonatal mortality, admittance to NICU, and peripartum hemorrhage rates and Apgar scores were similar (Table 1). Baseline serum creatinine and eGFR levels of KTRs were 1 (0.8-1.2) mg/dl and 76.6 (59.9-91.5) ml/min/1.73 m2, respectively. Follow-up for a median of 105 months after the index birth showed higher serum creatinine levels at postpartum visits (p &amp;lt; 0.001) and last follow-up (p = 0.001) compared to baseline, with a tendency for increased proteinuria during pregnancies (Table 2). Six KTRs (11.3%) experienced composite kidney outcomes, including 5 patients with graft failure and 1 with doubling of serum creatinine. Conclusion KTRs exhibit comparable neonatal mortality and NICU rates but higher rates of preeclampsia and preterm birth. Notably, graft functions worsen significantly during postpartum follow-up.

#2504 Histopathological findings and cardiovascular events in kidney transplantation

Abstract Background and Aims Despite offering superior outcomes for patients with end-stage kidney disease, kidney transplantation poses significant cardiovascular risks. Recently, histopathological findings in chronic kidney disease patients have been associated with all-cause mortality and cardiovascular events, but there is scant data on this subject in kidney transplant recipients. This study assesses the relationship between histopathological findings in protocol biopsies of kidney grafts and cardiovascular events, graft loss, and mortality in renal transplant recipients. Method A prospective observational study included 530 renal transplant recipients at the Hospital Clínic de Barcelona from March 2015 to 2019, with follow-up until March 2023. Data included demographics, comorbidities, laboratory tests, and protocol allograft biopsies at 3 and 12 months post-transplant. Associations between histopathological findings and outcomes (cardiovascular events, graft loss, mortality) were analyzed. Results Chronic vascular lesions (CV) were significantly correlated with cardiovascular death and major adverse cardiovascular events (MACE) (OR 10.4 (1.6–66.4); p 0.002). Arteriolar hyalinosis and interstitial fibrosis were independently associated with all-cause mortality (OR 4.9 (1.1-21.4); p 0.02, and 1.2 (1.03-1.3), p 0.005; respectively) regardless of the estimated glomerular filtration rate (eGFR). Associations were also found between pre-transplant factors (diabetes, hypertension, hyperphosphatemia), active smoking, and deceased donors. Notably, post-transplant hypophosphatemia was related to MACE, suggesting a potential association with malnutrition though, this subject requires further investigation. Conclusion Histopathological findings in early protocol biopsies of kidney grafts, especially chronic vascular lesions, arteriolar hyalinosis, and interstitial fibrosis, have a potential predictive value for cardiovascular events, mortality, and graft outcomes in transplant recipients, irrespective of eGFR. These insights emphasize the importance of timely post-transplant histological assessments for risk stratification and personalized interventions. Prospective studies are imperative to validate these findings and improve customized care strategies in this population.

#1023 Patient outcomes and graft survival among kidney transplant recipients with chronic hepatitis C infection: a single center study

Abstract Background and Aims Previous studies have shown that kidney transplant_(KT) recipients with chronic hepatitis C (HCV) infection have lower survival rates after transplantation. With the emergence of direct-acting antiviral therapy for HCV infection, the long-term outcomes for these patients are still unknown. This aims to evaluate the 5-year graft and patient outcomes of kidney transplant recipients with HCV infection at the National Kidney and Transplant Institute. Method A retrospective cohort study of HCV-positive KT recipients which were compared to HCV-negative patients in the same post-transplantation period. Data gathered from the patient's in-hospital and outpatient records and MEDSYS database. Results Twelve(12) out of 117 KT recipients with HCV infection were included. Half of these patients had detectable HCV RNA before KT. There was no difference in recipients' age, gender, and donor type between the groups. HCV infection is significantly associated with and an independent predictor of graft loss, rejection, and mortality. Patient survival between groups did not show any significant difference. Rates of graft rejection, graft loss, and patient mortality among HCV-positive recipients did not show statistically significant difference between groups. Graft survival rates at 6 months, 1-, 3-, and 5 years post KT were significantly lower among HCV-positive KT recipients compared to HCV-negative recipients. There were no significant differences in renal function, presence of proteinuria, liver enzyme levels, and incidence of cirrhosis between the groups. Conclusion Graft survival was shorter in HCV-positive KT recipients. Patient survival, measures of kidney function, and liver-related complications were similar between HCV-positive and HCV-negative KT recipients after transplantation.