Antibody-mediated rejection (AMR) is an important but infrequent cause of pediatric liver allograft injury. There is a lack of standardized guidance, and treatment approaches vary across institutions. A writing group from the Society of Pediatric Liver Transplantation conducted a comprehensive review of the published literature and collected institutional guidance documents from pediatric transplant centers across the United States to synthesize current diagnostic and management approaches to AMR in pediatric liver transplant recipients. AMR is diagnosed by the presence of characteristic histologic injury, C4d deposition, circulating donor-specific antibody (DSA), and exclusion of alternative causes of graft dysfunction, including T cell-mediated rejection. Management strategies focus on reducing circulating DSA through therapeutic plasma exchange and suppressing ongoing immune activation with corticosteroids and intravenous immunoglobulin. In severe or refractory cases, targeted therapies such as rituximab, bortezomib, and eculizumab may be considered. A stepwise diagnostic and management algorithm is presented. This resource outlines a practical approach to the diagnosis and management of AMR in pediatric liver transplantation, serving as a reference for busy clinicians who may encounter this serious but underrecognized cause of graft dysfunction and loss.
BACKGROUND:There are limited data on how intraoperative hemodynamic factors influence pediatric kidney transplant outcomes, particularly across the different phases of graft reperfusion. With the widespread introduction of anesthesia information management systems, new opportunities have emerged to explore how intraoperative management affects transplant outcomes. METHODS:We conducted a retrospective cohort study at a single center, including transplant recipients under 19 years of age who underwent kidney transplantation between 2010 and 2022 (n = 121). Data were extracted from chart reviews, anesthesia records, and an intraoperative monitoring databank. Modeling for clinical variables alone, intraoperative variables alone, and combined clinical-intraoperative features was analyzed with respect to three outcomes: Unadjusted glomerular filtration rate at one-month post-transplant (uGFR1M), time to creatinine nadir, and length of hospital stay. RESULTS:Longer duration of pre-unclamp mean arterial pressure (MAP) below the 95th percentile (β = -0.086, p = 0.009), a greater number of inotropes used during the pre-unclamp period (β = -4.00, p = 0.017), and higher MAP variability in the first 30 min post-unclamp (β = -1.38, p = 0.006) were each independently associated with lower uGFR1M. A greater volume of fluid administered in the pre-unclamp period was independently associated with a longer time to creatinine nadir (β = 0.002, p = 0.01). CONCLUSIONS:Intraoperative features related to pre-unclamp volume resuscitation, MAP control, and post-unclamp hemodynamic instability are associated with slower graft function in pediatric kidney transplantation.
BACKGROUND:Among the most abundant viruses in the human blood virome are anelloviruses, including alpha-, beta-, and gammatorqueviruses (TTV, TTMV, and TTMDV). Whether anelloviruses are transmitted through kidney transplantation at a young age and subsequently persist in their new host is unknown. This study investigates the dynamics and composition of the anellome in the blood of six pediatric donor-recipient pairs, with monitoring beginning before transplantation and continuing until 2 years after transplantation. METHODS:Donors were sampled once, before donation, while recipients were sampled before and multiple times after transplantation (median 6.5 samples). Quantitative PCR, rolling circle amplification, Illumina sequencing, and SCANellome V2 analysis were used to detect, characterize, and compare anellovirus presence in donors and recipients. RESULTS:At baseline, four out of six donors tested positive for TTV by quantitative anellovirus PCR, three of whom had sufficient viral loads to enable genomic comparison with their recipients. All recipients tested positive at baseline, five had a moderate viral load (< 105 copies/mL), and one had > 109 copies of TTV DNA/mL. This recipient was already immunosuppressed before transplantation, and only in this recipient was a donor-derived anellovirus identified. This lineage was detected among 15 other lineages in the recipient and matched one of the four lineages identified in the donor. CONCLUSION:This finding demonstrates that anellovirus transmission from donor to recipient occurs in pediatric kidney transplantation. This may be associated with pre-existing immunosuppression.
BACKGROUND:Early graft function after pediatric kidney transplantation (KT) may be influenced by perioperative hemodynamic and fluid management variables. However, previous studies have yielded conflicting results. This study aimed to evaluate the impact of perioperative factors on early graft function in pediatric KT recipients. METHODS:This retrospective multicenter study included pediatric KT recipients from four academic centers in Turkiye and France. Early graft function was assessed using estimated glomerular filtration rate (eGFR) at postoperative day 7 and day 30. Delayed graft function (DGF) was defined as the need for dialysis within the first 7 days post-transplant. Mean arterial pressure (MAP) was calculated where reperfusion blood pressure data were available, and a sensitivity analysis accounting for transplant center was performed. Associations between perioperative variables and outcomes were evaluated using univariate and multivariate regression analyses. RESULTS:Ninety-seven patients were included (median age 154 months; 45.4% female). DGF occurred in 11.3% of recipients. In multivariate analysis, no perioperative variable was independently associated with DGF. Longer cold ischemia time was independently associated with lower 7-day eGFR (B = -0.05; 95% CI -0.10 to -0.01; p = 0.014). At 30 days, preemptive transplantation (B = -15.99; 95% CI -27.02 to -4.96; p = 0.005) and DGF (B = -36.94; 95% CI -58.39 to -15.50; p = 0.001) were independently associated with lower eGFR; the preemptive association was attenuated after accounting for transplant center. CONCLUSION:Intraoperative hemodynamic parameters were not independently associated with DGF or early graft function. At day 7, early graft function was primarily associated with cold ischemia time, whereas at day 30 it was mainly associated with preemptive transplantation status and DGF.
BACKGROUND:Donor-derived cell-free DNA (dd-cfDNA) is increasingly used as a noninvasive marker of kidney allograft injury, but adult-derived cutoffs may not be applicable to pediatric recipients, particularly in the setting of donor-recipient size mismatch. We evaluated dd-cfDNA levels in stable pediatric kidney transplant (KT) recipients and assessed variation by recipient weight and donor body mass index (BMI). METHODS:Retrospective data were collected from seven U.S. pediatric KT centers. Clinically stable recipients < 18 years of age (no de novo donor specific antibody, biopsy-proven rejection or BK viremia/nephropathy), with ≥ 2 dd-cfDNA measurements per year were included. Recipients were stratified by weight at dd-cfDNA collection (< 20 kg, 20-50 kg, > 50 kg). Donor BMI was categorized as underweight (≤ 18.5), normal (18.6-24.9), overweight (25-29.9), or obese (≥ 30). Comparisons were performed using linear mixed-effects models. RESULTS:Among 178 recipients, mean dd-cfDNA did not differ by recipient weight (< 20 kg: 0.51 ± 0.44; 20-50 kg: 0.65 ± 1.28; > 50 kg: 0.49 ± 0.70). Median dd-cfDNA was similar across donor BMI categories. However, among obese donors, recipients < 20 kg had 1.3-fold higher dd-cfDNA (p = 0.044). Donor-recipient body surface area mismatch > 1.5 was associated with 1.083-fold higher dd-cfDNA up to 5 years post-transplant (p = 0.016). CONCLUSIONS:In stable pediatric KT recipients, dd-cfDNA levels were well below the adult-derived 1% cutoff, reinforcing the generalizability of this cutoff to the pediatric population. Recipients < 20 kg with donor BMI > 30 kg/m2 or in the setting of a donor-recipient BSA mismatch > 1.5 were associated with higher dd-cfDNA levels.
BACKGROUND:Solid organ transplant (SOT) recipients face an increased risk of central nervous system (CNS) infections due to immunosuppression. The incidence of CNS infections in adult SOT recipients ranges from 0.4% to 10%, while it remains unknown in pediatric SOT recipients. Herein, we describe the incidence, clinical presentation, and outcomes of CNS infections in pediatric SOT recipients. METHODS:We conducted a single-center retrospective cohort study that included 1628 first-time SOT recipients ≤ 21 years of age from 2003 to 2023. RESULTS:We identified 23 patients with CNS infection representing an incidence of 2.3 per 1000 patient-years. They occurred in 8/400 (2%) heart; 7/570 (1.2%) liver; 5/220 (2.3%) lung; 2/400 (0.5%) kidney, and 1/38 (2.6%) multi-organ transplant recipients. Documented symptoms included fever in 15/23 (65%), altered mental status in 7/23 (30%), nausea and emesis in 6/23 (26%), and headache in 6/23 (26%). Neuroimaging was performed in 15/23 (65%) patients with CNS infection; 10/15 (67%) had abnormal findings. Bacterial and fungal infections predominated, each accounting for 8/23 (35%) cases, followed by viral infections in 7/23 (30%) cases. Among patients with CNS infection, all-cause mortality was observed in 9/23 (39%), while it was 263/1605 (16%) in those without a CNS infection (p < 0.01). CONCLUSIONS:CNS infections in SOT recipients are rare and presentation can be non-specific, though associated with a high mortality. These findings highlight the importance of maintaining clinical awareness of CNS infection in SOT recipients.
BACKGROUND:The study aimed to analyze the outcomes of TCRαβ/CD19-depleted and T-replete graft with post-transplant cyclophosphamide (PTCY) in haploidentical hematopoietic stem cell transplantation (HSCT) in inborn errors of immunity (IEI). PATIENTS AND METHODS:We performed a retrospective analysis of children from birth to 18 years of age with IEI who underwent haploidentical HSCT between April 2009 and September 2024, with a minimum follow-up period of 12 months. RESULTS:A total of 230 children with IEI underwent HSCT in the 15-year period, where 105 (45%) underwent haploidentical HSCT and were included in the analysis with a follow up period of 0.5 to 170 months. TCR-αβ/CD19-depleted HSCT was done in 65 (62%) children, while T-replete graft with PTCY was used in 40 (38%) children. There was no significant difference in engraftment rates, acute and chronic graft versus host disease rates between both the cohorts: T-depleted group-89%, 8.6%, 12% respectively versus T-replete group-85%, 15%, 17.5% respectively. The 5-year overall survival was 62% (95% CI: 48%-73%) in the TCR-αβ/CD 19-depleted cohort in comparison to 54% (95% CI: 48% to 73%) in the PTCY cohort. When the survival was compared in children less than 2 years of age, it was 60% in the TCR-αβ/CD 19 depleted cohort versus 37% in PTCY cohort (p value of 0.001). CONCLUSION:Survival was superior in the T depleted cohort as compared to the T replete group, with viral reactivation remaining a persisting challenge. Letermovir prophylaxis and memory cell add-back would be potential strategies to improve survival.
BACKGROUND:Pediatric kidney transplant recipients are susceptible to a range of complications that may compromise allograft function and are associated with significant morbidity. Urologic complications represent an important subset that may necessitate multiple radiological and/or surgical interventions. METHODS:Our previously reported modified extravesical ureteroneocystostomy technique was designed to avoid routine stent placement at the time of transplant as well as to reduce postoperative urologic complications. Here, we reviewed 107 consecutive pediatric kidney transplant recipients transplanted at our center since 2014 who received no stent placement at the time of transplant. RESULTS:The observed percentage who developed a urologic complication during the first 12 months post-transplant was 3.7% (4/107), and only 2.8% (3/107) required surgical intervention. Ureteral obstruction/stricture was observed in 2.8% (3/107), with two being due to UPJ obstruction, and one being due to the occurrence of multiple kidney stones that occluded the distal ureter/ureterovesical junction (UVJ). No urinary leaks, 0.0% (0/107), were observed during the first 12 months post-transplant. Additionally, poor bladder compliance along with Grade 4 vesicoureteral reflux occurred in one patient. One patient (who developed a UPJ obstruction) was successfully managed with interventional radiology alone. The other three patients required surgical intervention: ureteral reimplantation for the patient having UVJ obstruction due to multiple kidney stones, pyeloureterostomy in one patient with a UPJ obstruction, and bladder augmentation along with (ureter, ileum, and ileal) Monti Mitrofanoff in the patient having poor bladder compliance. CONCLUSIONS:In pediatric kidney transplantation, our extravesical ureteroneocystostomy technique without routine ureteral stent placement was associated with a low incidence of post-transplant urological complications.
BACKGROUND:The morbidity and mortality after living donor liver transplantation (LDLT) in children with Alagille syndrome (AGS) are complex because of the multisystem involvement of the disease. Evidence on long-term outcomes and donor selection remains limited. METHODS:This multicenter retrospective study included 49 pediatric patients with AGS who underwent LDLT between 2001 and 2020 at eight institutions in Japan, Korea, and Turkey. Clinical characteristics, transplant indications, donor selection, posttransplant growth, renal function, and complications were analyzed. RESULTS:The median age at LDLT was 1.1 years. Major indications for transplantation were severe growth failure (91.8%) and advanced liver disease with hepatic dysfunction. Based on donor evaluations, 11% of candidates were excluded due to genetic or anatomical concerns. The 5-year patient and graft survival rates were 93.7% and 91.5%, respectively. LDLT before 2 years of age was associated with significantly greater catch-up in height and weight. Long-term renal deterioration was observed, particularly beyond 15 years after transplantation, and older age at LDLT was an independent predictor of lower long-term estimated glomerular filtration rate. Cardiac anomalies were manageable with appropriate preoperative evaluation, whereas vasculopathies were observed after adolescence. A history of Kasai portoenterostomy did not significantly affect posttransplant outcomes. CONCLUSIONS:LDLT provides excellent short- and long-term outcomes in pediatric AGS. Timely LT may improve growth and preserve renal function before progressive multisystem complications become established. Long-term surveillance and comprehensive donor evaluation remain essential.
BACKGROUND:Pediatric kidney transplant recipients and their caregivers require comprehensive education to support self-management. Increasingly, families supplement clinic teaching with online platforms such as Google and YouTube, yet the quality, readability, and usefulness of these resources are uncertain. METHODS:Structured searches on Google and YouTube were conducted using patient-style questions and medically oriented key terms across four prioritized topics: healthy eating, exercise, travel, and mental health. Resources were screened for relevance and assessed for accuracy, completeness (defined as including all key facts needed to support recommendations), readability, and actionability (defined as providing clear, practical steps users can follow). Two pediatric transplant healthcare providers independently reviewed each resource. Two researchers assessed understandability and actionability using the Patient Education Materials Assessment Tool (PEMAT), and readability using multiple readability tools. RESULTS:Searches yielded 87 Google and 41 YouTube resources; most targeted adult transplant recipients. Healthcare providers assessed 65% of Google and 68% of YouTube resources to be accurate, but only 18% and 5% were factually complete. Actionable recommendations were identified in 42% (Google) and 29% (YouTube). Readability ranged from grade 5 to 17, with only 6 of 82 Google resources meeting the recommended grade 6 or lower. Mean understandability scores were 67% for both platforms. Actionability scores averaged 39% (Google) and 77% (YouTube). Resources suitable for pediatric audiences (n = 28) had similar readability and understandability scores but slightly higher actionability (Google: 43%, YouTube: 81%). Most resources lacked pediatric focus, co-creation, and practical guidance. CONCLUSIONS:Online searches generated limited high-quality resources tailored to pediatric needs. Healthcare providers should guide families to vetted resources and consider co-creating materials to improve relevance and impact.
BACKGROUND:Kidney transplantation confers prolonged and improved quality of life versus dialysis for patients with end-stage kidney disease (ESKD). Delayed graft function (DGF) increases the risk of allograft rejection and decreases allograft survival. In adults, prolonged warm (WIT) and cold ischemia time (CIT) increase risk of DGF, and machine perfusion (MP) during organ transportation reduces this risk. However, there is a paucity of data regarding risk factors for DGF in children. METHODS:We retrospectively evaluated risk and protective factors for DGF in patients aged 18 months to 21 years who underwent kidney transplantation at Cincinnati Children's Hospital Medical Center between 11/1/2017 and 11/30/2021. DGF was defined as receiving dialysis within 7 days post-transplant. RESULTS:Nine of 89 (10%) patients developed DGF. Patients with DGF had longer median WIT (49 IQR: 44-57 vs. 37 min IQR: 30-43; p = 0.002) and were more likely to have received a deceased donor (DD) allograft (p = 0.04, RR1.7 (95% CI: 1.2-2.4)). There was no difference in CIT between those who did and did not experience DGF (464 IQR:329-788 vs. 271 min. IQR:271-788; p = 0.16). No patients who received DD-MP kidneys developed DGF. DGF in recipients of DD-non-MP kidneys had longer WIT (53 IQR: 43-57 vs. 36 min. IQR: 30-44; p < 0.009). CONCLUSION:Increased WIT increases the risk of DGF in pediatric kidney transplant recipients, whereas MP appears to be protective against DGF and may ameliorate the adverse effect of CIT. DGF was rare in the cohort and further studies are necessary due to the low incidence of DGF.
Liver transplantation (LT) in patients with situs inversus (S-I) is rare and technically challenging. The literature on such cases, particularly in pediatric populations, remains limited. Here, we report the surgical considerations and outcomes of two pediatric recipients with situs inversus abdominalis who underwent liver transplantation for biliary atresia (BA). We conducted a retrospective descriptive analysis of two pediatric patients with S-I who underwent LT for BA. Pretransplant imaging, intraoperative details, and posttransplant outcomes were evaluated. Additionally, we performed a systematic review of the literature on LT in patients with S-I. We describe the successful living donor liver transplantation (LDLT) of two pediatric patients with S-I abdominalis and BA, each presenting with complex anatomical variations, including polysplenia, intestinal malrotation, and vascular anomalies such as absence of the inferior vena cava (IVC). Both patients underwent technically demanding procedures requiring customized vascular and biliary reconstructions, along with definitive correction of intestinal malrotation to restore anatomical intestinal orientation. Both patients had an uncomplicated immediate postoperative course. During follow-up, one patient developed a diaphragmatic hernia that required surgical repair. Our systematic review confirms that, although rare, pediatric LT in patients with S-I is increasingly reported with favorable outcomes. These findings support the feasibility and safety of LT in children with S-I when guided by meticulous preoperative planning and intraoperative adaptability. Liver transplantation in pediatric patients with S-I is feasible and can be performed safely with careful preoperative planning and tailored surgical techniques. Our experience, together with the available literature, supports the inclusion of these patients as suitable candidates for transplantation despite their complex anatomy.
BACKGROUND:Survival in pediatric liver transplantation (PLT) has significantly improved in infants under 1 year, but < 10 kg and < 6 months continue to have poor outcomes with a paucity of information on ultra-low weight (ULW) infants (< 5 kg). We compared intraoperative vasopressor use in < 5 kg versus 5-< 9.9 kg PLT recipients. METHODS:We conducted a single-center retrospective review of all PLT recipients < 10 kg at time of transplant from 2009 to 2022, excluding multi-organ transplantation. We collected data on demographics, diagnosis, intraoperative vasoactive infusions, blood loss and requirements, and abdominal closure timing. Outcomes data include total mechanical ventilation, intensive care and hospital length of stay days, 1-year patient and graft survival and thrombotic complications. RESULTS:ULW < 5 kg and 5-9.9 kg patients showed average weight of 4.53 versus 7.30 kg (p-value < 0.0001) and average age of transplant 3.36 versus 7.90 months (p-value 0.0002). The most common etiology of liver disease for ULW versus 5-9.9 kg was neonatal acute liver failure (3 of 5) versus biliary atresia (41 of 63). No significant difference in anhepatic time, abdominal closure, blood products transfused/kg, estimated blood loss/kg was noted. Total days of mechanical ventilation, ICU and hospital LOS were similar between groups. ULW trends toward higher doses of vasopressors during PLT, most notably at end of case compared to 5-9.9 kg (p = 0.06). Overall, 1-year graft and patient survival were 91% and 94%, respectively. HAT and PVT did not appear to be associated with VIS by phase of surgery, but PVT occurred relatively more in the < 5 kg group (2 vs. 4) and HAT in the 5-9.9 kg group (0 vs. 3). CONCLUSIONS:Results show etiology of liver failure differs and < 5 kg trends to an increased amount of vasopressor use, especially at end of case, suggesting more hemodynamic instability requiring support; however, this did not correlate with measured hospital metrics. Split graft PLT recipients have more blood loss and require more transfusions. PVT was observed more in the < 5 kg cohort. Etiology, not just size or early age, may contribute to the higher and sustained pressor requirements and possible PVT risk in ULW infants.
OBJECTIVE:Long-term multidimensional evaluations of pediatric lung transplantation are limited. This study assessed the functional recovery, volumetric adaptation, and growth in pediatric recipients by comparing age and graft type. METHODS:This single-center, retrospective, descriptive study longitudinally reviewed 16 children (age < 18 years) who underwent bilateral deceased-donor lung transplantation. Perioperative characteristics, pulmonary function, computed tomography (CT)-derived lung volume, somatic growth, and survival were analyzed. Overall survival (OS) and chronic lung allograft dysfunction (CLAD)-free survival were estimated using the Kaplan-Meier method, and longitudinal physiological and developmental patterns were assessed descriptively. RESULTS:In the younger group (≤ 10 years, n = 7) and the older group (> 10 years, n = 9), lobar transplantation was performed in 5 (71.4%) and 3 (33.3%) patients, respectively. CLAD was diagnosed in 1 younger recipient (14.3%) and 2 older recipients (22.2%). OS did not differ significantly between age groups (log-rank p = 0.96), and CLAD-free survival was comparable (log-rank p = 0.73). CT volumetry demonstrated progressive postoperative lung expansion with similar temporal trajectories across age groups and between lobar and whole-lung grafts. Growth patterns demonstrated meaningful postoperative improvement, with many children who exhibited faltering pretransplant growth demonstrating catch-up toward individualized percentile curves. CONCLUSIONS:Pediatric lung transplantation results in favorable long-term recovery, including functional improvement, durable volumetric adaptation, and partial restoration of growth dynamics. Comparable outcomes between lobar and whole-lung grafts support the use of size-reduced grafts in cases of donor-recipient mismatch.
BACKGROUND:Kidney transplant education promotes early partnership between children, caregivers, and clinicians by sharing information and fostering engagement to maximize outcomes. We evaluated educational materials' accessibility, alignment with shared priorities, and portrayal of life participation. METHODS:We performed a content analysis of pediatric kidney transplant centers' educational materials to assess how they addressed 4 key priorities: kidney function, infection, survival, and life participation. We assessed printed materials' readability using Simple Measures of Gobbledygook and Flesch-Kincaid tools and audiovisual materials' understandability and actionability using the Patient Education Materials Assessment Tool. RESULTS:Of 73 centers approached, 23 (32% response) provided educational packets. Only 6 packets (26%) included materials targeted to children. Average reading grade level was high (SMOG 8.9 ± 1.7; Flesch-Kincaid 9.5 ± 1.8), with only 1 packet written at sixth-grade level. Audiovisual materials were not highly understandable or actionable. Among key priorities shared by children, caregivers, and clinicians, packets most frequently addressed infection, followed by kidney function, life participation, and survival. We identified 3 themes reflecting portrayal of the key priority of life participation: hope and caution-a proactive, optimistic tone about certain aspects of life participation and cautious tempering of expectations for others; maximizing physical transplant benefits-detailed guidance on physical activity, but limited attention to psychosocial well-being; and being "normal"-a focus on restoring physical health while framing mental and emotional distress as potential threats to normalcy. CONCLUSIONS:There are important opportunities to enhance transplant educational materials by tailoring content to children, increasing accessibility, and more consistently and comprehensively addressing concerns about life participation after transplant.
BACKGROUND:Early and precise assessment of graft health is vital for pediatric liver transplant patients; however, current monitoring methods depend largely on invasive biopsies and non-specific biochemical tests. Donor-derived cell-free DNA (ddcfDNA) has emerged as a promising non-invasive biomarker for detecting graft injury, but data on its early post-transplant kinetics, baseline levels, and the influence of donor and recipient factors in stable pediatric populations remain limited. OBJECTIVE:To prospectively characterize the early postoperative patterns of ddcfDNA and explore baseline ranges in clinically stable pediatric recipients of living donor liver transplants (LDLT), while evaluating the influence of recipient and donor demographic and clinical variables on ddcfDNA dynamics for improved non-invasive graft monitoring. METHODS:In a cohort of 22 stable pediatric LDLT recipients, ddcfDNA levels were measured longitudinally using the Trunome GrafAssure assay at postoperative days 1-2, 7, 10-14, and 30-31. Concurrent liver function tests and clinical data were also collected. Statistical analyses were performed to evaluate correlations and determine the significance of the observed relationships. RESULTS:ddcfDNA peaked on days 1-2 (~9.0%, 2.3 ng/mL), declined sharply by day 7 (~2.4%, 1.0 ng/mL), and stabilized by days 30-31 (~2.0%, 0.2 ng/mL). Liver enzymes decreased gradually. The absolute quantification values and the ddcfDNA percentage correlated with AST and ALT early post-transplant, with associations diminishing over time. Recipient and donor characteristics did not significantly affect ddcfDNA levels. CONCLUSION:dd-cfDNA demonstrates rapid postoperative clearance and stable longitudinal trends in clinically stable pediatric liver transplant recipients. The baseline values and kinetic patterns characterized provide a preliminary reference framework for future comparative studies evaluating dd-cfDNA behavior during graft dysfunction, rejection, or other adverse events in the early postoperative and surveillance periods.
