Biopsy-proven Acute Rejection Research Articles

Evaluation of Tacrolimus Concentrations and Clinical Outcomes Between Extended and Immediate Release Formulations in Kidney Transplant.

Objectives: Tacrolimus remains the mainstay of immunosuppression in kidney transplantation. Understanding the relationship between therapeutic tacrolimus levels and outcomes of acute rejection, patient/graft survival, and tolerability are important. The relationship between time to therapeutic tacrolimus levels and outcomes has not been well established, specifically with the use of extended release tacrolimus formulation (LCP-Tac). This study investigated time to therapeutic tacrolimus levels of 2 tacrolimus formulations, LCP-Tac and immediate release tacrolimus (IR-Tac), as a predictor of clinical outcomes. Methods: This was a single-center, retrospective, cohort study of kidney transplant recipients at Duke Hospital between 2013-2021. The primary objective evaluated the difference in time to therapeutic tacrolimus levels with LCP-Tac vs IR-Tac regimens. Secondary endpoints included time within therapeutic range during the first 3months post-transplant, incidence of biopsy-proven rejection, development of de novo donor specific antibodies, and patient and allograft survival at 12months post-transplant. Results: 128 patients were included (63 in LCP-Tac group and 65 in IR-Tac group). The time to therapeutic tacrolimus level was similar between formulations (7.2 days with LCP-Tac compared to 6.7days with IR-Tac, P = .63). The time within therapeutic range during the first 3months post-transplant, via modified Rosendaal, was similar with LCP-Tac and IR-Tac (56.1% vs 64.8%, respectively). Rates of biopsy-proven acute rejection at 12months were similar (7/63 (11.1%) compared to 4/65 (6.2%)). There was no difference in patient/graft survival between groups. Conclusions: The time to therapeutic tacrolimus levels did not differ based on tacrolimus formulation and was not correlated with clinical outcomes.

Incidence, epidemiology and outcomes of acute allograft rejection following liver transplantation in Australia.

Acute allograft rejection is a well-known complication of liver transplantation (LT). The incidence, epidemiology and outcomes of acute rejection have not been well-described in Australia. We retrospectively studied consecutive adults who underwent deceased-donor LT at a single centre between 2010-2020. Donor and recipient data at time of LT and recipient outcomes were collected from a prospective LT database. Liver biopsy reports were reviewed and only a graft's first instance of biopsy-proven acute rejection was analysed. During the study period, 796 liver transplants were performed in 770 patients. Biopsy-proven rejection occurred in 34.9% of transplants. There were no significant changes in the incidence of rejection over time (linear trend p=0.11). The median time to first episode of rejection was 71 days post-LT: 2.2% hyperacute, 50.4% early (≤90d) and 47.5% late rejection (>90d). Independent risk factors for rejection were younger recipient age at transplant (aHR 0.98 per year increase, 95% CI 0.97-1.00, p=0.01), and ABO-incompatible grafts (aHR 2.55 vs. ABO-compatible, 95% CI 1.27-5.09, p<0.01) while simultaneous multiorgan transplants were protective (aHR 0.21 vs. LT only, 95% CI 0.08-0.58, p<0.01). Development of acute rejection (both early and late) was independently associated with significantly reduced graft (aHR 3.13, 95% CI 2.21-4.42, p<0.001) and patient survival (aHR 3.42, 95% CI 2.35-4.98, p<0.001). In this 11-year Australian study, acute LT rejection occurred in 35%, with independent risk factors of younger recipient age and ABO-incompatible transplant while having a simultaneous multiorgan transplant was protective. Acute rejection was independently associated with reduced graft and patient survival after adjustment for other factors.

Comparing the prognostic performance of iBOX and biopsy-proven acute rejection for long-term kidney graft survival

Biopsy-proven acute rejection (BPAR) occurs in approximately 10% of kidney transplant recipients in the first year, making superiority trials unfeasible. iBOX, a quantitative composite of estimated glomerular filtration rate, proteinuria, antihuman leukocyte antigen donor-specific antibody, and + full/− abbreviated kidney histopathology, is a new proposed surrogate endpoint. BPAR’s prognostic ability was compared with iBOX in a pooled cohort of 1534 kidney transplant recipients from 4 data sets, including 2 prospective randomized controlled trials. Discrimination analyses showed mean c-statistic differences between both iBOX compared with BPAR of 0.25 (95% confidence interval: 0.17-0.32) for full iBOX and 0.24 (95% confidence interval: 0.16-0.32) for abbreviated iBOX, indicating statistically significantly higher c-statistic values for the iBOX prognosis of death-censored graft survival. Mean (± standard error) c-statistics were 0.81 ± 0.03 for full iBOX, 0.80 ± 0.03 for abbreviated iBOX, and 0.57 ± 0.03 for BPAR. In calibration analyses, predicted graft loss events from both iBOX models were not significantly different from those observed. However, for BPAR, the predicted events were significantly (P < .01) different (observed: 64; predicted: 70; full iBOX: 76; abbreviated iBOX: 173 BPAR). IBOX at 1-year posttransplant is superior to BPAR in the first year posttransplant in graft loss prognostic performance, providing valuable additional information and facilitating the demonstration of superiority of novel immunosuppressive regimens.

Efficacy and safety of single-dose anti-thymocyte globulin versus basiliximab induction therapy in pediatric kidney transplant recipients: A retrospective comparative cohort study.

This study aimed to compare the efficacy and safety of basiliximab (BAS) versus a single dose of anti-thymocyte globulin (r-ATG) induction therapy in pediatric kidney transplant recipients (KTRs). This single-center retrospective comparative cohort study included all pediatric KTRs from May 2013 to April 2018 and followed up to 12 months. In the first period, all recipients received BAS, while from May 2016, a single 3 mg/kg dose of r-ATG was instituted. Maintenance therapy consisted of a calcineurin inhibitor plus prednisone plus azathioprine or mycophenolate. A total of 227 patients were included (BAS, n = 113; r-ATG, n = 114). The main combination of immunosuppressive drugs was tacrolimus, prednisone, and azathioprine in both groups (87% vs. 88%, p = .718). Patients receiving r-ATG showed superior survival-free of the composite endpoint (acute rejection, graft loss, or death; 76% vs. 61%, p = .003; HR 2.08, 1.29-3.34, p = .003) and lower incidence of biopsy-proven acute rejection (10% vs. 21%, p = .015). There was no difference in the overall incidence of CMV infection (33% vs. 37%, p = .457), PTLD (1% vs. 3%, p = .309), 30-day hospital readmissions (24% vs. 23%, p = .847), and kidney function at 12 months (86 ± 29 vs. 84 ± 30 mL/min/1.73m2, p = .614). These data suggest that induction therapy with a single 3 mg/kg dose of r-ATG is associated with higher efficacy for preventing acute rejection and similar safety profile compared to BAS.

Safety and efficacy of early corticosteroid withdrawal in liver transplant recipients: A randomized controlled trial.

Prolonged use of steroids after liver transplantation (LT) significantly increases the risk of diabetes or cardiovascular disease, which can adversely affect patient outcomes. Our study evaluated the effectiveness and safety of early steroid withdrawal within the first year following LT. This study was conducted as an open-label, multicenter, randomized controlled trial. Liver transplant recipients were randomly assigned to one of the following two groups: Group 1, in which steroids were withdrawn two weeks posttransplantation, and Group 2, in which steroids were withdrawn three months posttransplantation. This study included participants aged 20 to 70 years who were scheduled to undergo a single-organ liver transplant from a living or deceased donor at one of the four participating centers. Between November 2012 and August 2020, 115 patients were selected and randomized into two groups, with 60 in Group 1 and 55 in Group 2. The incidence of new-onset diabetes after transplantation (NODAT) was notably higher in Group 1 (32.4%) than in Group 2 (10.0%) in the per-protocol set. Although biopsy-proven acute rejection, graft failure, and mortality did not occur, the median tacrolimus trough level/dose/weight in Group 1 exceeded that in Group 2. No significant differences in safety parameters, such as infection and recurrence of hepatocellular carcinoma, were observed between the two groups. The present study did not find a significant reduction in the incidence of NODAT in the early steroid withdrawal group. Our study suggests that steroid withdrawal three months posttransplantation is a standard and safe immunosuppressive strategy for LT patients.

Impact of Cumulative 6 mg/kg Antithymocyte Globulin on Early Posttransplant Outcomes in Kidney Transplant Recipients with Delayed Graft Function.

Introduction: Delayed graft function in kidney transplant is associated with an increased risk of rejection and graft loss. Use of rabbit antithymocyte globulin induction in delayed graft function has been correlated with less rejection compared to basiliximab, but optimal dosing remains unknown. Program Evaluation Aims: The purpose of this evaluation was to retrospectively assess the short-term effectiveness and tolerability of a clinical protocol that increased the net state of immunosuppression in delayed graft function kidney transplant recipients using cumulative 6 mg/kg rabbit antithymocyte globulin induction. Design: This retrospective cohort included 88 kidney transplant recipients with delayed graft function, transplanted between January 2017 and March 2021, who either received cumulative 4.5 mg/kg pre-protocol or 6 mg/kg post-protocol rabbit antithymocyte globulin. Outcomes evaluated were biopsy-proven acute rejection and incidence of graft loss, infection, and cytopenia at 6 months. Results: A significant reduction of biopsy-proven acute rejection incidence occurred post-protocol implementation (10/33, 30.3% vs 6/55, 10.9%; P = .04). Of those with rejection, significantly less post-protocol patients were classified as acute cellular rejection (9/10, 90.0% vs 2/6, 33.3%; P = .04). No death-censored graft loss was observed in either group. Rates of cytopenia and infection were similar pre- versus post-protocol implementation. Conclusion: Increasing the exposure to rabbit antithymocyte globulin and maintenance immunosuppression in delayed graft function kidney transplant recipients was tolerable and significantly reduced rejection occurrence at 6 months.

Conversion from twice-daily everolimus to once-daily sirolimus in long-term stable liver transplant recipients

BackgroundAfter organ transplantation, strategies for simplifying the therapeutic regimen may improve adherence and prevent acute organ rejection and/or late graft loss. The present study aimed to evaluate the safety and efficacy of conversion from everolimus (EVR) twice daily to sirolimus (SIR) once daily in a large cohort of liver transplantation (LT) patients. MethodsWe included 108 LT patients with at least 12 months of post-transplant follow-up and no rejection episodes in the last year. Conversion was based on a 1:1 ratio (but eventually adapted to available formulations of SIR). ResultsThe median age at the time of conversion was 68.9 years (range: 26.1–83.6); 75.0% were men. The main indications for mTOR inhibitor use were renal failure (38.9%) and/or a history of malignancy (37.0%). Median conversion time after LT was 14.8 years (range: 2.3–31.5). The median dose of EVR and SIR (initially) was 1.50 mg/day (range: 0.5–4.5). The mean follow-up after conversion was 15.8±4.4 months. Median serum EVR/SIR trough levels before/after conversion were 3.85 ng/mL vs. 6.32 ng/mL (p < 0.05), i.e. a 1:1.64 ratio. At the end of follow-up after conversion, the median dose of SIR was 1.25 mg/day (range: 0.5–3.5), and the mean serum SIR trough level was 5.23 ng/mL; 9 patients (8.3%) had returned to EVR, because of side effects (mainly digestive), that resolved thereafter. No biopsy-proven acute rejection episode was observed. Finally, 87.1% of patients considered the conversion beneficial and the cost was reduced by 50.3%. ConclusionThe results of our study indicate that conversion from once-daily EVR to once-daily SIR in stable LT patients is safe, but needs dose adaptations and careful monitoring.

Outcomes of Kidney Transplantation Among COVID-19 Recovered Patients in a Single Transplant Center

The COVID-19 pandemic significantly lowered kidney transplantation (KT) rates worldwide, and studies regarding outcomes of patients who developed COVID-19 infection before KT are limited, especially in low to middle-income countries. To determine the 1-year graft and patient survival of kidney transplant recipients who recovered from COVID-19 infection before KT. We retrospectively reviewed all adult end-stage renal disease patients who underwent KT at the National Kidney and Transplant Institute from June 2020 through October 2021. Transplant parameters, graft and patient survival, pretransplant COVID-19 infection, and post-KT infectious complications were recorded. Data was analyzed using two-tailed descriptive statistical tests. Of the 219 recipients, 23 (11%) had COVID-19 infection within 1 to 16 months before KT. The mean age of KT recipients was 36 years (range, 25-57), and 61.9% had chronic glomerulonephritis as primary renal disease. The mean duration from COVID-19 recovery to KT was 79 days (range, 21-207). There was no significant difference in the 1-year biopsy-proven acute rejection in the 2 groups, at 4.5% vs 12.5% for the COVID-19 and non-COVID-19 group, respectively. Both the 1-year graft and patient survival were similar in the COVID-19 and non-COVID-19 groups at 98.4% vs 100% and 100% vs 98.44%, respectively. There was no significant difference in biopsy-proven acute rejection, 1-year graft, and patient survival among patients who had a prior COVID-19 infection vs those who did not. Kidney transplantation appears safe when performed at least 1 month from COVID-19 infection.

Cannabis use is associated with reduced access to kidney transplantation and an increased risk of acute rejection post-transplant.

The association between cannabis use and access to waitlisting, transplantation, and post-transplant outcomes remains uncertain. Patients referred for kidney transplant (KT) to the University Health Network from January 1, 2003, to June 30, 2020, and followed until December 31, 2020, were included. Predictors of reported cannabis use were examined using a logistic regression model. The association between cannabis use and time to clearance for KT, undergoing KT, and post-transplant outcomes was evaluated using Cox proportional hazards models. Among 3734 patients, the prevalence of reported cannabis use was 11.8%. Cannabis use was associated with a lower likelihood of KT clearance (adjusted hazard ratio [aHR] .82 [95% confidence interval (CI): .72, .94]). Once cleared for KT, cannabis use did not predict the subsequent receipt of KT (aHR .92, [95% CI: .79, 1.08]). Among 2091 KT recipients, cannabis use was associated with a higher likelihood of biopsy-proven acute rejection (aHR 1.55, [95% CI: 1.06, 2.27]). The relative hazard of death-censored graft failure was similarly elevated (aHR 1.60 [95% CI: .95, 2.72]). Cannabis use did not predict total graft failure (aHR 1.33 [95% CI: .90, 1.96]), death with graft function (aHR 1.06 [95% CI: .59, 1.89]), or hospital readmission in the first-year post-transplant (aHR 1.26 [95% CI: .95, 1.68]). Cannabis users have less access to transplantation and an increased risk of acute rejection, possibly leading to more graft loss. Further studies are warranted to understand possible mechanisms for the increased risk of allograft immune injury among cannabis users.

Tacrolimus's Time Below Therapeutic Range Is Associated With Acute Pancreatic Graft Rejection and the Development of De Novo Donor-specific Antibodies.

Tacrolimus is pivotal in pancreas transplants but poses challenges in maintaining optimal levels due to recipient differences. This study aimed to explore the utility of time spent below the therapeutic range and intrapatient variability in predicting rejection and de novo donor-specific antibody (dnDSA) development in pancreas graft recipients. This retrospective unicentric study included adult pancreas transplant recipients between January 2006 and July 2020. Recorded variables included demographics, immunosuppression details, HLA matching, biopsy results, dnDSA development, and clinical parameters. Statistical analysis included ROC curves, sensitivity, specificity, and predictive values. A total of 131 patients were included. Those with biopsy-proven acute rejection (BPAR, 12.2%) had more time (39.9% ± 24% vs. 25.72% ± 21.57%, p = 0.016) and tests (41.95% ± 13.57% vs. 29.96% ± 17.33%, p = 0.009) below therapeutic range. Specific cutoffs of 31.5% for time and 34% for tests below the therapeutic range showed a high negative predictive value for BPAR (93.98% and 93.1%, respectively). Similarly, patients with more than 34% of tests below the therapeutic range were associated with dnDSA appearance (38.9% vs. 9.4%, p = 0.012; OR 6.135, 1.346-27.78). In pancreas transplantation, maintaining optimal tacrolimus levels is crucial. Suboptimal test percentages below the therapeutic range prove valuable in identifying acute graft rejection risk.

Functional MRI evaluation of blood oxygen dependent (BOLD) in renal allograft dysfunction: a prospective study.

Blood oxygen level dependent-magnetic resonance imaging (BOLD-MRI) is a non-invasive functional imaging technique that can be used to assess renal allograft dysfunction. To evaluate the diagnostic performance of BOLD-MRI using a 3-T scanner in discriminating causes of renal allograft dysfunction in the post-transplant period. This prospective study was conducted on 112 live donor-renal allograft recipients: 53 with normal graft function, as controls; 18 with biopsy-proven acute rejection (AR); and 41 with biopsy-proven acute tubular necrosis (ATN). Multiple fast-field echo sequences were performed to obtain T2*-weighted images. Cortical R2* (CR2*) level, medullary R2* (MR2*) level, and medullary over cortical R2* ratio (MCR) were measured in all participants. The mean MR2* level was significantly lower in the AR group (20.8 ± 2.8/s) compared to the normal group (24 ± 2.4/s, P <0.001) and ATN group (27.4 ± 1.7/s, P <0.001). The MCR was higher in ATN group (1.47 ± 0.18) compared to the AR group (1.18 ± 0.17) and normal functioning group (1.34 ± 0.2). Both MR2* (area under the curve [AUC] = 0.837, P <0.001) and MCR (AUC = 0.727, P = 0.003) can accurately discriminate ATN from AR, however CR2* (AUC = 0.590, P = 0.237) showed no significant difference between both groups. In early post-transplant renal dysfunction, BOLD-MRI is a valuable non-invasive diagnostic technique that can differentiate between AR and ATN by measuring changes in intra-renal tissue oxygenation.

Fixed low dose versus concentration-controlled initial tacrolimus dosing with reduced target levels in the course after kidney transplantation: results from a prospective randomized controlled non-inferiority trial (Slow & Low study)

Optimal initial tacrolimus dosing and early exposure of tacrolimus after renal transplantation is not well studied. In this open-label, 6 months, multicenter, randomized controlled, non-inferiority study, we randomly assigned 432 renal allograft recipients to receive basiliximab induction, mycophenolate and steroids and either standard prolonged-release tacrolimus (trough levels: 7-9ng/ml; Standard Care arm), or an initial 7-day fixed 5mg/day dose of prolonged-release tacrolimus followed by lower tacrolimus predose levels (trough levels: 5-7ng/ml; Slow & Low arm). The primary end point was the combined incidence rate of biopsy-proven acute rejections (BPAR; including borderline), graft failure, or death at 6 months with a non-inferiority margin of 12.5%. (EudraCT-Nr: 2013-001770-19. The combined primary endpoint in the Slow & Low arm was non-inferior compared to the Standard Care arm (22.1% versus 20.7%; difference: 1.4%, 90% CI-5.5% to 8.3%). The overall rate of BPAR including borderlines was similar (Slow & Low 17.4% versus Standard Care 16.6%). Safety parameters such as delayed graft function, kidney function, donor specific HLA-antibodies, infections, or post-transplantation diabetes mellitus did not differ. This is the first study to show that an initial fixed dose of 5mg per day followed by lower tacrolimus exposure is non-inferior compared to standard tacrolimus therapy and equally efficient and safe within 6 months after renal transplantation. These data suggest that therapeutic drug monitoring for prolonged release tacrolimus can be abandoned until start of the second week after transplantation. Investigator-initiated trial, financial support by Astellas Pharma GmbH.

Detrimental impact of early biopsy-proven rejection in liver transplantation.

Existing literature offers conflicting conclusions about whether early acute cellular rejection influences long-term outcomes in liver transplantation. We retrospectively collected donor and recipient data on all adult, first-time liver transplants performed at a single center between 2008 and 2020. We divided this population into two cohorts based on the presence of early biopsy-proven acute cellular rejection (EBPR) within the first 90 days post-transplant and compared outcomes between the groups. There were 896 liver transplants that met inclusion criteria with 112 cases (12.5%) of EBPR. Recipients who developed EBPR had higher biochemical Model for End-Stage Liver Disease scores (28vs. 24, p<.01), but other donor and recipient characteristics were similar. Recipients with EBPR had similar overall survival compared to patients without EBPR (p=.09) but had decreased graft survival (p<.05). EBPR was also associated with decreased time to first episode of late (>90 days post-transplant) rejection (p<.0001) and increased vulnerability to bacterial and viral infection (p<.05). In subgroup analysis of recipients with autoimmune indications for liver transplantation, EBPR had a more pronounced association with patient death (hazard ratio [HR] 3.9, p<.05) and graft loss (HR 4.0, p<.01). EBPR after liver transplant is associated with inferior graft survival, increased susceptibility to late rejections, and increased vulnerability to infection.

Sirolimus in combination with low-dose extended-release tacrolimus in kidney transplant recipients.

Many challenges remain for long-term survival of renal allografts. Once-daily sirolimus (SRL) combined with low-dose extended-release tacrolimus (LER-TAC) may improve medication adherence and reduce the potential nephrotoxicity of calcineurin inhibitors (CNI) compared with standard immunosuppression regimens, thus potentially improving long-term graft survival. This retrospective, observational, single-center, propensity score matching (PSM) study compared conversion to SRL combined with low-dose ER-TAC and mycophenolic acid (MPA) combined with standard-dose TAC in kidney transplant recipients. After PSM, there were 56 patients in each group. Efficacy, safety, and medication adherence were evaluated over 12 months. There was no significant difference between the two groups in terms of graft and recipient survival and incidence of biopsy-proven acute rejection (p = 1.000), and none of the recipients developed dnDSA after conversion. The mean eGFR improved in SRL + LER-TAC group after conversion compared to before conversion (51.12 ± 20.1 ml/min/1.73 m2 vs. 56.97 ± 19.23 ml/min/1.73 m2, p < 0.05). The medication adherence at 12 months after conversion was superior to before conversion (p = 0.002). Our findings suggest that an immunosuppressive regimen of SRL combined with low-dose ER-TAC is no less effective and safe than standard immunosuppressive regimens for renal transplant recipients and may improve graft renal function and medication adherence.

Impact of Renal Replacement Therapy on Rejection among Liver Transplant Recipients.

Introduction: Renal dysfunction in liver transplant recipients is associated with an increased risk of morbidity and mortality, with an even higher risk among patients requiring renal replacement therapy. There is limited data evaluating rejection outcomes in patients requiring renal replacement therapy after liver transplant. Program evaluation aims: To evaluate the incidence of biopsy-proven acute rejection, recipient and graft survival, infection, renal dysfunction, and immunosuppression practices. Design: This was a single-center, retrospective, cohort study. To be eligible, patients were deceased donor liver transplant recipients ≥18 year of age transplanted between January 2017 and August 2019 who received steroid-only induction and tacrolimus as part of their initial immunosuppression regimen. Results: Recipients that required renal replacement therapy (N  =  86) were compared to those who received no renal replacement therapy (N  =  158). Biopsy-proven acute rejection at 1-year posttransplant was significantly higher among those requiring renal replacement therapy (36% vs 13%, P < .001). Patient survival at 12 months was 77% for those requiring renal replacement therapy and 94% for those not requiring renal replacement therapy (P < .001). Infection (HR 3.8, 95% CI 1.6-8.8; P < .001), but not rejection (HR 0.7, 95% CI 0.3-1.7; P  =  .5) was an independent predictor of mortality. The use of renal replacement therapy after liver transplant necessitated careful titration of immunosuppression to balance the detrimental risks of infection versus rejection in this high-risk population.

Transcriptomic Landscape of Circulating Extracellular Vesicles in Heart Transplant Ischemia-Reperfusion.

Ischemia-reperfusion injury (IRI) is an inevitable event during heart transplantation, which is known to exacerbate damage to the allograft. However, the precise mechanisms underlying IRI remain incompletely understood. Here, we profiled the whole transcriptome of plasma extracellular vesicles (EVs) by RNA sequencing from 41 heart transplant recipients immediately before and at 12 h after transplant reperfusion. We found that the expression of 1317 protein-coding genes in plasma EVs was changed at 12 h after reperfusion. Upregulated genes of plasma EVs were related to metabolism and immune activation, while downregulated genes were related to cell survival and extracellular matrix organization. In addition, we performed correlation analyses between EV transcriptome and intensity of graft IRI (i.e., cardiomyocyte injury), as well as EV transcriptome and primary graft dysfunction, as well as any biopsy-proven acute rejection after heart transplantation. We ultimately revealed that at 12 h after reperfusion, 4 plasma EV genes (ITPKA, DDIT4L, CD19, and CYP4A11) correlated with both cardiomyocyte injury and primary graft dysfunction, suggesting that EVs are sensitive indicators of reperfusion injury reflecting lipid metabolism-induced stress and imbalance in calcium homeostasis. In conclusion, we show that profiling plasma EV gene expression may enlighten the mechanisms of heart transplant IRI.

Evaluation of serial monitoring of donor-specific antibodies in pediatric and adult intestinal/multivisceral transplant recipients.

The study purpose was to add to limited literature assessing anti-HLA donor-specific antibody (DSA) appearance, clearance, specificity, and impact in intestinal/multivisceral (MV) transplant as well as the value of serial monitoring following an institutional protocol shift implementing serial monitoring. This single-center retrospective review included intestinal/MV recipients transplanted 1/1/15-9/31/17 with completed DSA testing. Patients were divided into groups based on DSA presence post-transplant. The primary outcome was biopsy-proven acute rejection (BPAR). Secondary outcomes included graft loss and death. Descriptive analysis of DSA was completed. Of the 35 intestinal/MV recipients (60% pediatric) with DSA testing, 24 patients had post-transplant DSA. Fifteen patients in the DSA(+) group had T-cell-mediated BPAR versus five in the DSA(-) group (63% vs 45%, p = .47). Days to BPAR were 25 [IQR 19-165] (DSA(+) group) versus 232 [IQR 25.5-632.5] (DSA(-) group) (p = .066). There were no differences between groups for graft loss or death. One hundred and five DSA were identified in the DSA(+) group with 63% being class II, and 54% cleared during follow-up. DSA were directed against 50 different HLA alleles, with the most common being directed against HLA- DQ (35%). Time to first DSA and to clearance did not differ between class I and II. Findings confirm previous data that suggest post-transplant DSA in this population may lead to increased BPAR or shorter time to BPAR, although not statistically significant. Most DSA were identified within the first month after transplant, and ahead of rejection identification on biopsy. DSA therefore may have utility as an early rejection biomarker and use may be considered in place of early protocol biopsies, particularly in pediatric patients. We identified novel findings of DSA directed against a large breadth of HLA in intestinal/MV patients.

Clinical relevance of the living kidney donor profile index in Korean kidney transplant recipients.

The Living Kidney Donor Profile Index (LKDPI) was developed in the United States to predict graft outcomes based on donor characteristics. However, there are significant differences in donor demographics, access to transplantation, proportion of ABO incompatibility, and posttransplant mortality in Asian countries compared with the United States. We evaluated the clinical relevance of the LKDPI score in a Korean kidney transplant cohort by analyzing 1860 patients who underwent kidney transplantation between 2000 and 2019. Patients were divided into three groups according to LKDPI score: <0, 1-19.9, and ≥20. During a median follow-up of 119months, 232 recipients (12.5%) experienced death-censored graft loss, and 98 recipients (5.3%) died. High LKDPI scores were significantly associated with increased risk of death-censored graft loss independent of recipient characteristics (LKDPI 1-19.9: HR 1.389, 95% CI 1.036-1.863; LKDPI ≥20: HR 2.121, 95% CI 1.50-2.998). High LKDPI score was also significantly associated with increased risk of biopsy-proven acute rejection and impaired graft renal function. By contrast, overall patient survival rates were comparable among the LKDPI groups. High LKDPI scores were associated with an increased risk of death-censored graft loss, biopsy-proven acute rejection, and impaired graft renal function among a Korean kidney transplant cohort.

Noninvasive graft monitoring using donor-derived cell-free DNA in Japanese liver transplantation.

To evaluate the use of donor-derived cell-free DNA (dd-cfDNA) in diagnosing graft injuries in Japanese liver transplantation (LTx), including family-related living donors. A total of 321 samples from 10 newly operated LTx recipients were collected to monitor the early dynamics of dd-cfDNA levels after LTx. Fifty-five samples from 55 recipients were collected during protocol biopsies (PB), whereas 36 samples from 27 recipients were collected during event biopsies, consisting of 11 biopsy-proven acute rejection (AR), 20 acute dysfunctions without rejection (ADWR), and 5 chronic rejections. The levels of dd-cfDNA were quantified using a next-generation sequencer based on single nucleotide polymorphisms. The dd-cfDNA levels were elevated significantly after LTx, followed by a rapid decline to the baseline in patients without graft injury within 30days post-LTx. The dd-cfDNA levels were significantly higher in the 11 samples obtained during AR than those obtained during PB (p<0.0001), which decreased promptly after treatment. The receiver operator characteristic curve analysis of diagnostic ability yielded areas under the curve of 0.975 and 0.897 for AR (rejection activity index [RAI]≥3) versus PB and versus non-AR (ADWR+PB). The dd-cfDNA levels during AR were elevated earlier and correlated more strongly with the RAI (r=0.740) than aspartate aminotransferase/alanine aminotransferase. The dd-cfDNA levels were neither associated with graft fibrosis based on histology nor the status of donor-specific antibodies in PB samples. Donor-derived cell-free DNA serves as a sensitive biomarker for detecting graft injuries in LTx. Further large-scale cohort studies are warranted to optimize its use in differentiating various post-LTx etiologies.

Renal Transplantation in Patients With Tuberculosis: A Single-center Experience From an Endemic Region.

Despite being a common infection in end-stage kidney disease patients, there are no evidence-based guidelines to suggest the ideal time of transplantation in patients on antitubercular therapy (ATT). This study aimed to examine the outcome of transplantation in patients while on ATT compared with those without tuberculosis (TB). This was a retrospective study. Renal transplant recipients transplanted while on ATT were compared with a 1:1 matched group (for age, sex, diabetic status, and type of induction agent) of patients without TB at the time of transplant. Patient outcomes included relapse of TB and graft and patient survival. There were 71 patients in each group. The mean duration for which ATT was given pretransplant was 3.8 ± 2.47 mo. The average total duration of ATT received was 12.27 ± 1.25 mo. Mortality in both the groups was similar (8.4% in the TB group versus 4.5% in the non-TB group; P = 0.49). None of the surviving patients had recurrence of TB during the follow-up. Death-censored graft survival (98.5% in the TB group versus 97% in the non-TB group; P = 1) and biopsy-proven acute rejection rates (9.86% in the TB group versus 8.45% in the non-TB group; P = 1) were also similar in both the groups. Successful transplantation in patients with end-stage kidney disease on ATT is possible without any deleterious effect on patient and graft survival and no risk of disease recurrence. Multicentric prospective studies are needed.