Long-term outcomes of two-dose alemtuzumab induction in pediatric kidney transplantation.

BACKGROUND: Alemtuzumab is a lymphocyte depleting agent used for induction in kidney transplant, but long-term information on its use in pediatric recipients remains sparse. METHODS: We performed a single-center retrospective cohort study of 57 pediatric kidney transplant recipients receiving alemtuzumab 20 mg/m2/dose ×2 doses for induction immunosuppression. All patients underwent surveillance biopsies, and 91.3% underwent steroid withdrawal by day 4 post-transplant. Outcomes of interest included graft survival, development of donor specific antibodies (DSA), incidence of viremia and PTLD, and duration of lymphopenia. RESULTS: Median follow-up time was 7.9 years (IQR 5-13.6 years). Median graft survival was 16.5 years (95% CI 11.6-unknown). DSA developed in 36.5% at a median of 944 days (IQR 252-2113 days). Incidences of BK polyomavirus DNAemia (BKPyV-DNAemia), CMV DNAemia, and EBV DNAemia were 38.6%, 22.8%, and 14%, respectively; one patient developed PTLD at 13.3 years post-transplant. Median duration of lymphopenia was 365 days (IQR 168-713 days); 19.3% of patients remained lymphopenic at 3 years post-transplant. There was no association between duration of lymphopenia and graft survival, rejection, DSA detection, or viremia. CONCLUSIONS: A two-dose alemtuzumab induction protocol can have excellent outcomes with a steroid-free maintenance immunosuppression regimen. More comprehensive, multicenter, comparative studies of pediatric kidney transplant are needed to improve long-term outcomes.

Long-term outcome of pediatric renal transplantation with donors younger than 6 years.

BACKGROUND: Renal transplantation is currently the best treatment option for patients with end-stage renal disease. However, the use of kidneys from donors under 6 years of age as a possibility to increase the organ pool in pediatric recipients remains a controversial matter. We aimed to investigate whether donor age is associated to the long-term functionality of the renal graft. Likewise, we analyzed the adaptation of the graft to the ascending functional requirements in the pediatric patient. METHODS: Retrospective study of the results obtained in pediatric recipients transplanted with grafts from donors between 3 and 6 years of age, comparing them with those of grafts from donors older than 6 years. Among the variables compared are cumulative graft survival, renal size, need for antiproteinuric therapy, GFR, incidence of rejection, pyelonephritis, renal failure and surgical or tumor complications. RESULTS: A total of 43 transplants were performed with donors aged 3-6 years, and 42 transplants with donors older than 6 years. Cumulative graft survival at 5 years was 81% for the younger donor group compared to 98% for the older donor group (p < .05). At 8 years, cumulative graft survival for donors <6 years was 74%. As for the mean estimated graft survival, it was 11.52 years for the younger donor group and 14.51 years for older donors. During follow-up, the younger donor group presented greater renal enlargement and need for antiproteinuric therapy. The older donors group had a higher GFR during the first year of follow-up, which then equalized in both groups. There were no statistically significant differences in the incidence of acute or chronic rejection, acute pyelonephritis, acute renal failure or surgical or tumor complications. CONCLUSIONS: Renal transplants of grafts equal to or less than 6 years old have good short-term and acceptable long-term results in pediatric patients.

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

BACKGROUND: 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). METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

[Mid-term efficacy evaluation of ABO incompatible living relative kidney transplantation based on protocol biopsy].

Objective: To evaluate the mid-term efficacy of ABO incompatible living donor kidney transplantation (ABOi-KT) based on the results of routine renal biopsy for transplantation. Methods: Retrospective collection of clinical data from 23 pairs of ABOi-KT donors and recipients at the First Affiliated Hospital of Sun Yat-sen University from July 2015 to November 2021. ABOi-KT was performed on recipients after desensitization treatment, and the results of routine kidney transplant biopsy at 1 week, 1 month, 3 months, 6 months, and 12 months after surgery were analyzed. Combined with blood type antibody levels and renal function recovery, the mid-term efficacy of ABOi-KT was evaluated. Results: Among the 23 recipients, there were 19 males and 4 females; age range from 19 to 47 years old [(29.6±6.7) years old], all underwent ABOi-KT successfully after receiving desensitization treatment. The follow-up time was (44.6±22.4) months, of which 22 cases were followed up for more than 1 year. The incidence rates of rejection reactions at 1 week, 1 month, 3 months, 6 months, and 12 months after surgery were 15.0% (3/20), 11.1% (1/9), 7.7% (1/13), 25.0% (3/12), and 12.5% (1/8), respectively. For receptors with rejection reactions, targeted anti-rejection therapy was performed based on clinical symptoms and various indicators. Borderline T cell mediated rejection (TCMR) can be converted to mild tubular inflammation after anti-rejection treatment. The positive rate of complement C4d in peritubular capillaries was 95.0% (19/20) one week after surgery, and the positive rate of complement C4d was 100% at 3 and 12 months after surgery. The cumulative survival rates at 1, 3, 5, and 7 years after surgery were all 100%. The cumulative survival rates at 1, 3, 5, and 7 years after kidney transplantation were 100%, 93.3%, 84.0%, and 84.0%, respectively. Except for 2 recipients who underwent transplantation in 2017 and experienced kidney failure at 30 and 49 months after surgery, all other transplanted kidneys survived. Conclusions: The results of routine renal transplant biopsy show that ABOi-KT has a good mid-term therapeutic effect. The pathological changes of ABOi-KT can be dynamically observed through routine renal transplant biopsy and targeted treatment for rejection reactions can be provided accordingly.

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

BACKGROUND: The association between cannabis use and access to waitlisting, transplantation, and post-transplant outcomes remains uncertain. METHODS: 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. RESULTS: 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]). CONCLUSIONS: 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.

Immunosuppression and cancer risk in kidney transplant recipients: A retrospective cohort study.

We assessed whether contemporary immunosuppression agents were associated with cancer among kidney transplant recipients (KTR), and if this association varied by age and sex. We studied a retrospective province-wide cohort of primary KTR (1997-2016). Employing multivariable Cox models, we estimated associations of cumulative doses of prednisone, mycophenolate and tacrolimus administered over the past 10 years, lagged by 2 years, with the incidence of primary malignant neoplasms (PMN). We assessed interactions with age and sex. To assess the impact of exposure recency, we used weighted cumulative exposure (WCE) modeling. Among 1064 KTR, 108 (10.2%) developed PMN over median follow-up of 73 months (interquartile range: 32-120). Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of 0.96 (0.64-1.43), 1.34 (0.96-1.86), and 1.06 (0.88-1.29) were estimated for cumulative daily doses of prednisone (5 mg), mycophenolate (1000 mg), and tacrolimus (2 mg) administered continuously over the past 10 years, respectively. PMN risk associated with cumulative tacrolimus exposure was modified by age (interaction p = .035) and was more pronounced in 15-year and 30-year-old KTR (aHRs of 1.57 [1.08-2.28] and 1.31 [1.03-1.66], respectively) in comparison to older KTR. PMN risk increase associated with higher cumulative mycophenolate dose was more pronounced in females (aHR = 1.86 [1.15-3.00]) than in males (aHR = 1.16 [0.74-1.81]; interaction p = .131). WCE analyses suggested increased PMN risk the higher the mycophenolate doses taken 5-10 years ago. A trend toward increased PMN risk with long-term mycophenolate exposure, particularly in females, and more pronounced risk with long-term tacrolimus exposure in younger KTR, identify opportunities for tailored immunosuppression to mitigate cancer risk.

Efficacy and Safety of Mycophenolate Mofetil In De Novo Renal Transplantation in a Retrospective Cohort of Transplant Recipients in Colombia-Esmitren Study.

BACKGROUND: To describe and establish the efficacy and safety of Mycophenolate Mofetil (Micoflavin) in patients with de novo renal transplantation during one-year post-transplant follow-up. As secondary objectives, the behavior of mycophenolic acid (MPA) C0 levels in this population, the relationship between MPA levels and renal function of the grafts, the incidence of acute rejection, and the incidence of adverse effects were evaluated. METHODS: A prospective cohort study was conducted on patients who received a first kidney transplant from a deceased donor between March 1, 2021, and February 28, 2022, at the Alma Mater of Antioquia Hospital of the Antioquia's University, in Medellín, Colombia. MPA C0 levels were taken from the patients on days 15, 30, 90, 180, and 360 after the kidney transplantation. RESULTS: Patients presented MPA therapeutic levels in the study. The average of the MPA levels in the population was 2.5 µg/mL, with an IQR of 2.13 to 3.32. There were 5 acute rejections (27%), but none of the patients with acute rejection presented subtherapeutic levels of mycophenolate. No significant relationship was observed between mycophenolic acid levels and rejection (P = .255). The patients who completed the study had no gastrointestinal intolerance to mycophenolate, cytomegalovirus infections, or significant hematological complications. CONCLUSIONS: MMF (Micoflavin) maintained mycophenolic acid levels C0 within the therapeutic range, was well tolerated and without the presence of significant adverse events, and maintained stable renal function throughout the follow-up period in the population studied.

Lung transplantation in HIV seropositive recipients: An analysis of the UNOS registry.

BACKGROUND: Experience with lung transplantation (LT) in patients with human immunodeficiency virus (HIV) is limited. Many studies have demonstrated the success of kidney and liver transplantation in HIV-seropositive (HIV+) patients. Our objective was to conduct a national registry analysis comparing LT outcomes in HIV+ to HIV-seronegative (HIV-) recipients. METHODS: The United Network for Organ Sharing database was queried to identify LTs performed in adult HIV+ patients between 2016 and 2023. Patients with unknown HIV status, multiorgan transplants, and redo transplants were excluded. The primary endpoints were mortality and graft rejection. Survival time was analyzed using Kaplan-Meier analysis. RESULTS: The study included 17 487 patients, 67 of whom were HIV+. HIV+ recipients were younger (59 vs. 62 years, p = .02), had higher pulmonary arterial pressure (28 vs. 25 mm Hg, p = .04), and higher lung allocation scores (47 vs. 41, p = .01) relative to HIV- recipients. There were no differences in graft/recipient survival time between groups. HIV+ recipients had higher rates of post-transplant dialysis (18% vs. 8.4%, p = .01), but otherwise had similar post-transplant outcomes to HIV-recipients. CONCLUSIONS: This national registry analysis suggests LT outcomes in HIV+ patients are not inferior to outcomes in HIV- patients and that well-selected HIV+ recipients can achieve comparable patient and graft survival rates relative to HIV- recipients.

HLA matching between donors and recipients improves clinical liver transplant graft survival.

BACKGROUND AND AIMS: The importance of human leukocyte antigen (HLA) matching between liver transplant donors and recipients on graft survival remains unclear and is not a clinical consideration in liver transplantation. This study aimed to determine the relationship between HLA matching and liver graft survival using a large-scale multi-centre database (UNOS/OPTN) and multivariate logistic analysis. The secondary aim was to determine whether this relationship was influenced by transplant indication and donor status. METHODS: This retrospective observational analysis was performed using 22 702 liver transplant recipients from the UNOS/OPTN database. Patients were divided into two groups based on number of HLA mismatches (0-3 mismatches vs. 4-6 mismatches) and then subcategorized by indication and donor status. Risk-adjusted outcomes were assessed by multivariate Cox analysis adjusting for donor and recipient characteristics and visualized using Kaplan-Meier survival curves. RESULTS: Allograft survival and risk of acute rejection were associated with degree of HLA mismatch. This association between HLA mismatch and graft survival persisted in individuals who underwent transplant for hepatitis, metabolic, drug toxicity, and congenital indications. Donor status also influenced the relationship between HLA mismatch and graft survival. Graft survival in DBD recipients was longer than in DCD in the 4-6 HLA mismatch group, whereas no significant difference was found in the 0-3 HLA mismatch group. CONCLUSION: HLA mismatch significantly reduced graft survival and increased risk of acute rejection. This association was noted only in specific indications. These findings are of potential clinical relevance to organ allocation, allograft matching algorithms, immunosuppression protocols, and transplant surveillance.

Prevalence of mycophenolate mofetil discontinuation and subsequent outcomes in pediatric kidney transplant recipients: A PNRC study.

BACKGROUND: Mycophenolate Mofetil (MMF) is an effective immunosuppressant used in kidney transplant recipients to prevent acute rejection. Complications such as diarrhea, leukopenia, and infections may necessitate the reduction or discontinuation of MMF. The objective of the study was to investigate the prevalence, timing, and reasons for MMF discontinuation and its association with outcomes in pediatric kidney transplant recipients. METHODS: Seven Pediatric Nephrology Research Consortium (PNRC) centers participated in a retrospective analysis of kidney transplant recipients <21 years of age. Characteristics and outcomes of patients in whom MMF was discontinued were compared to those who continued taking MMF throughout the first 2 years post-transplant. RESULTS: The study population included 288 participants (mean age 11.2 years) from 7 North American transplant centers. MMF was discontinued in 93/288 (32%) of participants. Common reasons for discontinuation included infections (35%), diarrhea (32%), leukopenia (15%), and others (18%). Increased cumulative alloimmunity (55% vs. 42%, p = .02), increased number of hospitalizations (82% vs. 67%, p = .01), and viral replications (79% vs. 47%, p < .0001) were observed in the MMF discontinuation group compared to the continuation group. Greater eGFR decline also occurred in the MMF discontinuation group over 2 years of follow-up (-7 vs. -1 mL/min/1.73 m2 , p = .05). CONCLUSIONS: Almost a third of pediatric kidney transplant recipients who begin MMF for maintenance immunosuppression have it discontinued within the first 2 years post-transplant, and this subset of patients is more likely to experience adverse outcomes. New strategies are needed to manage MMF therapy and improve post-transplant outcomes.

A Head-to-head Comparison of De Novo Sirolimus or Everolimus Plus Reduced-dose Tacrolimus in Kidney Transplant Recipients: A Prospective and Randomized Trial.

BACKGROUND: Mammalian target of rapamycin inhibitors (mTORi), sirolimus (SRL) and everolimus (EVR), have distinct pharmacokinetic/pharmacodynamics properties. There are no studies comparing the efficacy and safety of de novo use of SRL versus EVR in combination with reduced-dose calcineurin inhibitor. METHODS: This single-center prospective, randomized study included first kidney transplant recipients receiving a single 3 mg/kg antithymocyte globulin dose, tacrolimus, and prednisone, without cytomegalovirus (CMV) pharmacological prophylaxis. Patients were randomized into 3 groups: SRL, EVR, or mycophenolate sodium (MPS). Doses of SRL and EVR were adjusted to maintain whole blood concentrations between 4 and 8 ng/mL. The primary endpoint was the 12-mo incidence of the first CMV infection/disease. RESULTS: There were 266 patients (SRL, n = 86; EVR, n = 90; MPS, n = 90). The incidence of the first CMV event was lower in the mTORi versus MPS groups (10.5% versus 7.8% versus 43.3%, P < 0.0001). There were no differences in the incidence of BK polyomavirus viremia (8.2% versus 10.1% versus 15.1%, P = 0.360). There were no differences in survival-free from treatment failure (87.8% versus 88.8% versus 93.3%, P = 0.421) and incidence of donor-specific antibodies. At 12 mo, there were no differences in kidney function (75 ± 23 versus 78 ± 24 versus 77 ± 24 mL/min/1.73 m 2 , P = 0.736), proteinuria, and histology in protocol biopsies. Treatment discontinuation was higher among patients receiving SRL or EVR (18.6% versus 15.6% versus 6.7%, P = 0.054). CONCLUSIONS: De novo use of SRL or EVR, targeting similar therapeutic blood concentrations, shows comparable efficacy and safety. The reduced incidence of CMV infection/disease and distinct safety profile of mTORi versus mycophenolate were confirmed in this study.

Feasibility of steroid-free tacrolimus-basiliximab immunosuppression in pediatric liver transplantation and predictors for steroid requirement.

Avoidance of steroids in pediatric liver transplantation may reduce toxicity and morbidity. The aim of this study was to analyze the feasibility of a steroid-free tacrolimus-basiliximab immunosuppression scheme, the risk factors associated with steroid requirement, and safety parameters. Patients who underwent liver transplantation for biliary atresia between 2011 and 2019 were included and followed for 6 months after transplantation. Immunosuppression consisted of tacrolimus-based treatment with basiliximab induction. Steroid-free survival was estimated, and risk factors for steroid requirement were evaluated using multivariate Cox regression analysis. A total of 76 patients were included, of whom 42 (55.3%) required steroids (>14 d) due to biopsy-proven acute rejection (47.6%, n = 20), instability in liver function tests (35.7%, n = 15), tacrolimus-related adverse drug reactions (14.3%, n = 6), or other reasons (bronchospasm episode, n = 1). Steroid-free survival was 45.9% (95% CI, 35.9-58.8). Independent factors associated with steroid requirement included tortuosity in tacrolimus trough levels (≥1.76 vs. <1.76: HR 5.8, 95% CI, 2.6-12.7; p < 0.001) and mean tacrolimus trough levels (≥ 6.4 ng/mL vs. < 6.4 ng/mL: HR 0.4, 95% CI, 0.2-0.7; p = 0.002). The rate of bacterial and viral infections was comparable between patients with and without steroids, although in the former group, cytomegalovirus infection developed earlier ( p = 0.03). Patients receiving steroids had higher total cholesterol, LDL, and HDL levels ( p < 0.05) during follow-up, but no changes in the height Z-score were observed 1 year after transplantation. Basiliximab induction in combination with tacrolimus-based treatment avoided steroid requirements in 45% of the patients. Tacrolimus variability and trough levels below 6.4 ng/mL independently increased the risk of steroid requirement. Further efforts should be focused on personalizing immunosuppressive treatment.

Heart Transplant Human Leukocyte Antigen Matching in the Modern Era.

BACKGROUND: Although numerous reports have studied the consequences of human leukocyte antigen (HLA) mismatching in renal transplantation, there are limited and outdated data analyzing this association in thoracic organ transplantation. Therefore, our study reviewed the impact of HLA mismatching at both the total and the loci levels in the modern-era heart-transplant procedure on survival and chronic rejection outcomes. METHODS: We performed a retrospective analysis of adult patients after heart transplant by using the United Network for Organ Sharing database from January 2005-July 2021. Total HLA and HLA-A, HLA-B and HLA-DR mismatches were analyzed. Survival and cardiac allograft vasculopathy were the outcomes of interest during a 10-year follow-up period using Kaplan-Meier curves, log-rank tests and multivariable regression models. RESULTS: A total of 33,060 patients were included in this study. Recipients with a high degree of HLA mismatching had increased incidences of acute organ rejection. There were no significant differences in mortality rates among any of the total or loci level groups. Similarly, there were no significant differences between total HLA mismatch groups in time to first cardiac allograft vasculopathy, though mismatching at the HLA-DR locus was associated with an increased risk of cardiac allograft vasculopathy. CONCLUSION: Our analysis suggests that HLA mismatch is not a significant predictor of survival in the modern era. Overall, the clinical implications of this study provide reassuring data for the continued use of non-HLA-matched donors in an effort to increase the donor pool. If HLA matching is to be considered for heart transplant donor-recipient selection, matching at the HLA-DR locus should take priority due to its association with cardiac allograft vasculopathy.

A Multicenter Retrospective Cohort Study on Management Protocols and Clinical Outcomes After ABO-incompatible Kidney Transplantation in India.

BACKGROUND: There is no robust evidence-based data for ABO-incompatible kidney transplantation (ABOiKT) from emerging countries. METHODS: Data from 1759 living donor ABOiKT and 33 157 ABO-compatible kidney transplantations (ABOcKT) performed in India between March 5, 2011, and July 2, 2022, were included in this retrospective, multicenter (n = 25) study. The primary outcomes included management protocols, mortality, graft loss, and biopsy-proven acute rejection (BPAR). RESULTS: Protocol included rituximab 100 (232 [13.18%]), 200 (877 [49.85%]), and 500 mg (569 [32.34%]); immunoadsorption (IA) (145 [8.24%]), IVIG (663 [37.69%]), and no induction 200 (11.37%). Mortality, graft loss, and BPAR were reported in 167 (9.49%), 136 (7.73%), and 228 (12.96%) patients, respectively, over a median follow-up of 36.3 mo. In cox proportional hazard model, mortality was higher with IA (hazard ratio [HR]: 2.53 [1.62-3.97]; P < 0.001), BPAR (HR: 1.83 [1.25-2.69]; P = 0.0020), and graft loss (HR: 1.66 [1.05-2.64]; P = 0.0310); improved graft survival was associated with IVIG (HR: 0.44 [0.26-0.72]; P = 0.0010); higher BPAR was reported with conventional tube method (HR: 3.22 [1.9-5.46]; P < 0.0001) and IA use (HR: 2 [1.37-2.92]; P < 0.0001), whereas lower BPAR was reported in the prepandemic era (HR: 0.61 [0.43-0.88]; P = 0.008). Primary outcomes were not associated with rituximab dosing or high preconditioning/presurgery anti-A/anti-B titers. Incidence of overall infection 306 (17.39%), cytomegalovirus 66 (3.75%), and BK virus polyoma virus 20 (1.13%) was low. In unmatched univariate analysis, the outcomes between ABOiKT and ABOcKT were comparable. CONCLUSIONS: Our largest multicenter study on ABOiKT provides insights into various protocols and management strategies with results comparable to those of ABOcKT.

Cyclosporine vs. tacrolimus after liver transplantation for primary sclerosing cholangitis - a propensity score-matched intention-to-treat analysis.

BACKGROUND & AIMS: There is controversy regarding the optimal calcineurin inhibitor type after liver transplant(ation) (LT) for primary sclerosing cholangitis (PSC). We compared tacrolimus with cyclosporine in a propensity score-matched intention-to-treat analysis based on registries representing nearly all LTs in Europe and the US. METHODS: From the European Liver Transplant Registry (ELTR) and Scientific Registry of Transplant Recipients (SRTR), we included adult patients with PSC undergoing a primary LT between 2000-2020. Patients initially treated with cyclosporine were propensity score-matched 1:3 with those initially treated with tacrolimus. The primary outcomes were patient and graft survival rates. RESULTS: The propensity score-matched sample comprised 399 cyclosporine-treated and 1,197 tacrolimus-treated patients with PSC. During a median follow-up of 7.4 years (IQR 2.3-12.8, 12,579.2 person-years), there were 480 deaths and 231 re-LTs. The initial tacrolimus treatment was superior to cyclosporine in terms of patient and graft survival, with 10-year patient survival estimates of 72.8% for tacrolimus and 65.2% for cyclosporine (p <0.001) and 10-year graft survival estimates of 62.4% and 53.8% (p <0.001), respectively. These findings were consistent in the subgroups according to age, sex, registry (ELTR vs. SRTR), time period of LT, MELD score, and diabetes status. The acute rejection rates were similar between groups. In the multivariable Cox regression analysis, tacrolimus (hazard ratio 0.72, p <0.001) and mycophenolate use (hazard ratio 0.82, p = 0.03) were associated with a reduced risk of graft loss or death, whereas steroid use was not significant. CONCLUSIONS: Tacrolimus is associated with better patient and graft survival rates than cyclosporine and should be the standard calcineurin inhibitor used after LT for patients with PSC. IMPACT AND IMPLICATIONS: The optimal calcineurin inhibitor to use after liver transplantation in patients with primary sclerosing cholangitis has yet to be firmly established. Since randomized trials with long follow-up are unlikely to be performed, multicontinental long-term registry data are essential in informing clinical practices. Our study supports the practice of using tacrolimus instead of cyclosporine in the initial immunosuppressive regimen after liver transplantation for patients with primary sclerosing cholangitis. The retrospective registry-based design is a limitation.

More than four decades of graft survival in pediatric kidney transplant recipients.

BACKGROUND: Early in the history of kidney transplantation, short-term graft survival was low. Yet some have had excellent long-term survival. Herein, we describe characteristics of pediatric recipients with > 40 years of graft survival currently alive with a functioning first graft. METHODS: We reviewed all pediatric (age < 18 years) kidney transplants performed at the University of Minnesota between January 1, 1970, and December 31, 1979 (n = 148), to identify all recipients currently alive with a functioning first graft. Data are presented as medians with interquartile ranges (IQR) and proportions. RESULTS: We identified 10 recipients with > 40-year graft survival (median follow-up: 45.0 years (IQR: 43.1, 48.1)). The median age at transplant was 13.8 years (IQR: 5.1, 16.3). All recipients were white; half were male. Of the 10, 4 had glomerulonephritis, 2 had congenital anomalies of the kidney and the urinary tract, 2 had congenital nephrotic syndrome, 1 had Alport syndrome, and 1 had cystic kidney disease as kidney failure cause. Nine patients received a living-related donor transplant, and 1 patient received a deceased-donor transplant. The median estimated glomerular filtration rate at 20 years post-transplant was 79.9 (IQR: 72.3, 98.4); at 30 years, 67.7 (IQR: 63.2, 91.8); and at 40 years, 80.3 ml/min/1.73 m2 (IQR: 73.7, 86.0). None developed rejection, 5 developed hypertension, 2 developed dyslipidemia, 1 developed diabetes, and 7 patients developed malignancy (4 skin cancer, 2 breast cancer, and 1 post-transplant lymphoproliferative disease). CONCLUSION: Pediatric kidney transplant recipients may achieve > 4 decades of graft survival. Cancer is a common complication warranting vigilant screening.

Incidence of Acute Rejection Compared With Endomyocardial Biopsy Complications for Heart Transplant Patients in the Contemporary Era.

BACKGROUND: The reference standard of detecting acute rejection (AR) in adult heart transplant (HTx) patients is an endomyocardial biopsy (EMB). The majority of EMBs are performed in asymptomatic patients. However, the incidence of treated AR compared with EMB complications has not been compared in the contemporary era (2010-current). METHODS: The authors retrospectively analyzed 2769 EMBs obtained in 326 consecutive HTx patients between August 2019 and August 2022. Variables included surveillance versus for-cause indication, recipient and donor characteristics, EMB procedural data and pathological grades, treatment for AR, and clinical outcomes. RESULTS: The overall EMB complications rate was 1.6%. EMBs performed within 1 mo after HTx compared with after 1 mo from HTx showed significantly increased complications (OR, 12.74, P < 0.001). The treated AR rate was 14.2% in the for-cause EMBs and 1.2% in the surveillance EMBs. We found the incidence of AR versus EMB complications was significantly lower in the surveillance compared with the for-cause EMB group (OR, 0.05, P < 0.001). We also found the incidence of EMB complications was higher than treated AR in surveillance EMBs. CONCLUSIONS: The yield of surveillance EMBs has declined in the contemporary era, with a higher incidence of EMB complications compared with detected AR. The risk of EMB complications was highest within 1 mo after HTx. Surveillance EMB protocols in the contemporary era may need to be reevaluated.

Immunosuppression-Free Life after Pediatric Liver Transplant: A Case-Control Study from the Society of Pediatric Liver Transplant (SPLIT) Registry.

OBJECTIVE: To compare long-term outcomes of pediatric liver transplant (LT) recipients off immunosuppression (IS) with matched controls on IS using data from the Society of Pediatric Liver Transplant (SPLIT) registry. STUDY DESIGN: This was a retrospective case-control study. SPLIT participants <18 years of age, ≥4 years after isolated LT, and off IS for ≥1 year (cases) were age- and sex-matched 1:2 to patients with the same primary diagnosis and post-LT follow-up duration (controls). Primary outcomes included retransplantation, allograft rejection, IS comorbidities, and prevalence of SPLIT-derived composite ideal outcome (c-IO) achieved at the end of the follow-up period. Differences were compared using multiple linear regression for continuous outcomes and logistic regression for dichotomous data. RESULTS: The study cohort was composed of 33 cases (42.4% male, 60.6% biliary atresia, median age at LT of 0.7 [P25, P75, 0.5, 1.6] years, median IS withdrawal time of 9 [P25, P75, 6, 12] years after LT) and 66 age- and sex-matched controls. No cases required retransplantation. Cases and controls had similar growth parameters, laboratory values, calculated glomerular filtration rates, rates of post-transplant lymphoproliferative disease, graft rejection, and attainment of c-IO. CONCLUSIONS: No differences in allograft rejection rates, IS complications, or c-IO prevalence were seen between SPLIT patients off IS and age- and sex-matched controls remaining on IS. Discontinuation of IS most commonly occurred in the context of rigorously designed IS withdrawal trials. The available sample size was small, affecting generalizability to the broader pediatric LT population.

Subtle Changes in Tacrolimus Levels Have an Impact on Early Donor-Specific Antibodies in Kidney Transplantation.

Introduction: The impact of each immunosuppressive agent on de novo donor-specific antibodies in kidney transplant recipients varies among extant literature. Project aims: Patterns in immunosuppression and the effects on incidence of de novo donor-specific antibodies were evaluated. Design: Adult kidney transplant recipients from 2017 to 2019 without preformed antibodies were sampled. Allograft function, de novo donor-specific antibodies, tacrolimus concentrations, duration of goal-dose antiproliferatives, and steroid doses were recorded. Outcomes included incidence of de novo donor-specific antibodies, and their relation to tacrolimus concentrations, time at goal-dose antiproliferatives, and steroid doses. Results: Recipients (N = 153) were followed for 1 year; all were crossmatch negative and received rabbit antithymocyte globulin induction. Sixteen (10%) recipients developed de novo donor-specific antibodies in a median of 31 days [interquartile range, IQR: 12-67 days], most were Class II antibodies (87.5%). Incidence of de novo donor-specific antibodies did not differ based on induction dosing. Tacrolimus levels in the first month were lower for patients with de novo donor-specific antibodies (8.8 ng/mL vs 10.4 ng/mL, P < .01). There was no difference in time on goal antiproliferative doses, but higher steroid doses (0.4 vs 0.3 mg/kg/d; P = .02) were noted in patients with antibodies. Steroid dosing was likely impacted by baseline risk factors. Conclusion: A significant association was found between lower tacrolimus concentrations early post-transplant and incidence of de novo donor-specific antibodies. This highlighted the importance of clinician attention to subtle changes in tacrolimus and the impact it can have on antibody risk in the early post-transplant period.

Clinical impact using low-dose mycophenolate mofetil with tacrolimus on infectious, noninfectious complications and acute rejection, in renal transplant: A single hospital experience in Mexico.

Evidence supporting a starting dose of 2 g/day of mycophenolate mofetil (MMF) in combination with tacrolimus (TAC) for renal transplantation (RT) is still limited, but maintaining a dose of <2 g could result in worse clinical outcomes in terms of acute rejection (AR). This study aimed to determine the association between AR and infectious and noninfectious complications after RT with a dose of 1.5 g vs 2 g of MMF. A prospective cohort study was performed with a 12-month follow-up of recipients of RT from living donors with low (1.5 g/day) or standard (2 g/day) doses of MMF. The association between adverse effects and complications and doses of MMF was examined using Cox proportional hazard models, and survival free of AR, infectious diseases, and noninfectious complications was evaluated using the Kaplan-Meier test. At the end of the follow-up, the incidence of infectious diseases was 52% versus 50% (P = .71) and AR was 5% versus 5% (P = .86), respectively. The survival rate free of gastrointestinal (GI) complications requiring medical attention was higher in the low-dose group than in the standard-dose dose (88% vs 45%, respectively; P < .001). The use of 1.5 g/day of MMF confers a reduction in GI complications without an increase in infectious diseases or the risk of AR.