Study protocol for the development and validation of a questionnaire evaluating predisposition to immunosuppressant medication non-adherence of kidney pre-transplant patients. The KATITA project.

Non-adherence to immunosuppressive medication after kidney transplant is an important cause of graft rejection and loss. Approaches to minimization of non-adherence have focused on the identification of episodes of medication non-adherence, but by then irreparable harm to the graft may already have occurred, and a more effective approach would be to adopt preventive measures in patients who may have difficulty in adhering to medication. The aim of this study protocol is to develop and validate a clinical questionnaire for assessing, in kidney transplant candidate patients in the pre-transplant setting, the predisposition to non-adherence to immunosuppressive medication. In this multicenter, prospective study, a pilot questionnaire in Brazilian Portuguese language, composed of Likert-scaled statements expressing patients' beliefs, behaviors and barriers regarding medication taking will be assembled from a literature review, from focus groups, and an expert panel. The pilot questionnaire will be administered to a minimum of 300 patients in kidney transplant waiting lists and exploratory factor analysis will be used for development of the definitive questionnaire. A random subsample of a minimum of 60 patients will have the scale re-administered after one month for evaluation of test-retest reliability. A multicenter, external validation study will include 364 kidney transplant candidates who will be evaluated immediately before surgery and at months 3, 6 and 12 post-transplant for assessment of concurrent validity, by comparison with two scales that assess medication non-adherence, and for determination of predictive validity using a triangulation method for assessment of medication non-adherence. Structural validity will be assessed with confirmatory factor analysis using structural equation modeling. Cross-cultural generalizability and validity will be assessed by a multicenter study, in which a translation of the scale to another language will be administered to kidney transplant candidate patients from a different culture, with a subsample being selected for test-retest. This study will be conducted in Spain with a Spanish translation of the scale.

Safety and Efficacy of Mycophenolate Mofetil Associated With Tacrolimus for Kidney-pancreas and Kidney Transplantation: A Systematic Review and Meta-Analysis of Randomized Studies.

INTRODUCTION: This study evaluated the efficacy and safety of mycophenolate mofetil (MMF) associated with tacrolimus (TAC) in patients undergoing kidney-pancreas and kidney transplants, in comparison with cyclosporine (CyA), azathioprine (AZA), everolimus (EVL), sirolimus (SRL), manitimus (MAN), mizoribine (MZR), and enteric-coated mycophenolate sodium (ECMPS) in combination or monotherapy. METHODS: A systematic review and meta-analysis of randomized clinical trials was performed. The outcomes comprised acute rejection, graft loss, and adverse events. RESULTS: Thirty studies were included. The main adverse events related to the TAC+MMF scheme were infection (36%; 95%CI: 26%-46%), including cytomegalovirus (CMV) (14%; 95%CI: 8%-20%); anemia (20%; 95%CI: 2%-37%); leukopenia (18%; 95%CI: 3%-33%); nausea (20%; 95%CI: 1%-39%); and diarrhea (26%; 95%CI:13%-40%). TAC+MMF was compared to the schemes AZA+TAC, CyA+AZA, CyA+MMF, CyA+SRL, ECMPS, EVL, MAN+TAC, MMF+SRL, MZR, TAC+AZA, TAC+EVR, TAC+MZR, TAC +SRL and TAC. TAC+MMF was associated with a lower risk of rejection than MMF monotherapy (RD: -0.24; 95%CI -0.46; -0.02). Comparing TAC+MMF with the other regimens, no significant difference was found for graft loss. TAC+MMF was associated with a higher risk of infections than MZR (RD: 0.174; 95%CI: 0.25; 0.323) and TAC monotherapy (RD: 0.07; 95%CI 0.003; 0.138). CONCLUSION: Gastrointestinal and hematological adverse events and infections are the most common with TAC+MMF for kidney-pancreas and kidney. TAC+MMF effectively prevents acute cellular rejection, and alternatives with AZA, CyA, SRL, ECMPS, EVL, MAN, and MSR have similar efficacy and safety profiles. TAC monotherapy and MZR may be associated with a lower risk of infections.

Adolescencia, adherencia y transición: Experiencia de un centro de trasplante renal pediátrico / Adolescence, adherence, and transition: Experience from a pediatric renal transplant center

Con el advenimiento de nuevas técnicas quirúrgicas y medicaciones inmunosupresoras la sobrevida de los niños trasplantados mejoró, llegando a la adultez. La continuidad de su tratamiento requiere un proceso planificado que permita su tránsito a un sistema de salud orientado al adulto. El objeto de este trabajo es mostrar la transición a centros de adultos en una cohorte de pacientes trasplantados renales en el Hospital Garrahan, describir sus características clínicas y demográficas, su evolución, y oportunidades de mejora implementadas. Debido a cambios médicos y su abordaje desde la interdisciplina, se dividió a la población en tres periodos: era 1 (1988-1999), era 2 (2000-2009), y era 3 (2010- 2023). En la era 1, 179 adolescentes continuaron su atención médica en un centro de adultos, 212 en la era 2 y 201 en la era 3. En la era 1 el seguimiento estaba coordinado por el nefrólogo de cabecera y eran consultados los servicios de Urología, Servicio Social y Salud Mental. En la era 2, se fortaleció el trabajo en interdisciplina y aún más a partir del 2011. Surgieron centros de trasplante de adultos que recibían adolescentes y médicos dedicados a ellos en forma preferencial. En la actualidad la transición comienza a los 12 años y progresa hasta los 18. El modelo implementado es la transición directa, entre el nefrólogo pediatra y el de adultos, con varias consultas secuenciales en ambos centros. Si bien la sobrevida del paciente e injerto mejoraron, el rechazo, asociado a no adherencia, es una asignatura por mejorar (AU)

With the advent of new surgical techniques and immunosuppressive medications, the survival of transplanted children has improved, allowing them to reach adulthood. The continuity of their treatment requires a planned process that facilitates their transition to an adult-oriented healthcare system. The aim of this study was to examine the transition to adult centers in a cohort of renal transplant patients at Garrahan Hospital, describing their clinical and demographic characteristics, their evolution, and the improvement opportunities implemented. Based on medical changes and the interdisciplinary approach, the population was divided into three periods: era 1 (1988- 1999), era 2 (2000-2009), and era 3 (2010-2023). In era 1, 179 adolescents continued their medical care in an adult center, 212 in era 2, and 201 in era 3. In era 1, follow-up was coordinated by the attending nephrologist with consultations from Urology, Social Services, and Mental Health Services. In era 2, interdisciplinary work was strengthened, and even more so since 2011. Adult transplant centers were created to receive adolescents with physicians dedicated to their care on a preferential basis. Currently, the transition begins at 12 years of age and progresses up to 18. The implemented model involves direct transition between the pediatric nephrologist and the adult nephrologist, with several sequential consultations in both centers. Although patient and graft survival have improved, rejection associated with non-adherence remains an area for improvement

Influence of Tacrolimus Intrapatient Variability on Allograft Rejection Frequency and Survival Following Liver Transplantation.

BACKGROUND: Tacrolimus is the primary calcineurin inhibitor used in immunosuppressive regimens to prevent allograft rejection (AR) after organ transplantation. Recent studies have linked intrapatient variability (IPV) of tacrolimus with AR occurrence and reduced survival, especially in kidney transplant recipients. However, limited data are available on the impact of tacrolimus IPV on adverse outcomes after liver transplantation (LT). AIMS: The aim of this study was to assess the association between tacrolimus IPV using various methodologies with acute AR and long-term patient survival after LT. METHODS: All patients who underwent LT from January 2010 to July 2021 were retrospectively evaluated. Tacrolimus IPV was calculated for each patient using the mean and SD, mean absolute deviation (MAD), coefficient of variation (CV), and time in therapeutic range (TTR). These measures were then compared with AR within the first 24 months after LT and to long-term survival. RESULTS: Out of 234 patients, 32 (13.7%) developed AR and 183 (78.2%) survived, with a mean follow-up of 101 ± 43 months. Tacrolimus IPV, assessed by mean, SD, MAD, and CV, was 8.3 ± 2.1, 2.7 ± 1.3, 32.0% ± 11.7%, and 39.4% ± 15.4%, respectively. There was no statistically significant correlation between Tacrolimus IPV and AR or survival post-LT. CONCLUSIONS: In a large cohort of patients from diverse racial backgrounds, tacrolimus IPV was not associated with clinically relevant outcomes such as AR and survival after LT.

Cost-Effectiveness Analysis of Pharmacological Treatment for Adult Kidney Transplant Recipients in Colombia.

OBJECTIVES: To evaluate cost-effective pharmacological treatment in adult kidney transplant recipients from the perspective of the Colombian health system. METHODS: A decision tree model for the induction phase and a Markov model for the maintenance phase were built. A review of the clinical literature was conducted to extract probabilities, and the life-years were used as the outcome. Costs were calculated using the administrative databases. The evaluating treatment schemes are organized by groups of evidence with direct comparisons. RESULTS: In the induction phase, anti-thymocyte immunoglobulin+ methylprednisolone is dominant, more effective, and less expensive, compared with basiliximab+methylprednisolone. In the maintenance phase, azathioprine (AZA) is dominant in contrast to mycophenolate mofetil (MFM) both with cyclosporine (CIC)+ corticosteroids (CE); CIC is dominant relative to sirolimus (SIR) and tacrolimus (TAC) (both with MFM+CE or AZA+CE), and TAC is dominant compared with SIR (in addition with MFM+CE or mycophenolate sodium [MFS]+CE); MFM is dominant in relation to MFS and everolimus, and SIR is more effective MFM but it does not exceed the threshold (in sum with TAC+CE); MFS and MFM are dominant relative to everolimus, and SIR is more effective than MFM, but it does not exceed the threshold (in addiction with CIC+CE); MFM is dominant in relation to TAC (in sum with SIR+CE), and CIC+AZA+CE is dominant in relation to TAC+MFM+CE. CONCLUSIONS: The base-case results for all evidence groups are consistent with the different sensitivity analyses.

Nonadherence to Immunosuppressant Therapy of Kidney Transplant Candidate Patients: External Validation of the KATITA-25 Scale.

BACKGROUND: The self-administered Kidney AlloTransplant Immunosuppressive Therapy Adherence (KATITA-25) questionnaire is a multidimensional scale for use in the pretransplant setting that evaluates the predisposition to nonadherence of patients who are candidates to kidney transplant. The scale has shown adequate internal consistency and test-retest reliability. This study presents the results of an external validation study of the KATITA-25 scale. METHODS: Patients >18 y old scheduled for kidney transplant were included in this multicenter study. The KATITA-25 scale was administered before surgery and then at 3-mo posttransplantation for evaluation of scale sensitivity to change. At this time, 2 validated medication adherence scales were applied for assessment of concurrent validity. For evaluation of predictive validity, nonadherence to immunosuppressive medication was assessed at 6 and 12 mo after transplantation by 3 independent methods: patient self-report of nonadherence using the Morisky-Green-Levine Medication Assessment Questionnaire scale, serum trough levels of immunosuppressants, and pharmacy refills. RESULTS: Three twenty-two patients were available for evaluation of concurrent validity and 311 patients of predictive validity. After kidney transplant, the median KATITA-25 score decreased from 20 to 8 ( P  < 0.001), demonstrating scale sensitivity to change, and the KATITA-25 score showed correlation with the Basel Assessment of Adherence to Immunosuppressive Medication Scale score (Spearman's ρ 0.18, P  = 0.002) and the Cuestionario para la Evaluación de la Adhesión al Tratamiento Antiretroviral scores (ρ -0.17, P  = 0.002), confirming concurrent validity. The nonadherence rate was 57.6%. The scale predictive validity was demonstrated by the area under the receiver operating characteristics curve (0.68), sensitivity (59.8%), specificity (68.2%), and positive predictive value (71.8%). CONCLUSIONS: This external validation study of KATITA-25 scale provided evidence of sensitivity to change, and structural, criterion, and predictive validity.

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.

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.

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.

Crossmatch assays in transplantation: Physical or virtual?: A review.

The value of the crossmatch test in assessing pretransplant immunological risk is vital for clinical decisions, ranging from the indication of the transplant to the guidance of induction protocols and treatment with immunosuppressants. The crossmatch tests in transplantation can be physical or virtual, each with its advantages and limitations. Currently, the virtual crossmatch stands out for its sensitivity and specificity compared to the physical tests. Additionally, the virtual crossmatch can be performed in less time, allowing for a reduction in cold ischemia time. It shows a good correlation with the results of physical tests and does not negatively impact graft survival. Proper communication between clinicians and the transplant immunology laboratory will lead to a deeper understanding of each patient's immunological profile, better donor-recipient selection, and improved graft survival.

Survival of Heart Transplant Patients with Chagas' Disease Under Different Antiproliferative Immunosuppressive Regimens. / Sobrevida de Pacientes Transplantados Cardíacos com Doença de Chagas Sob Diferentes Regimes de Imunossupressores Antiproliferativos.

Chagas' disease (CD) is an important cause of heart transplantation (HT). The main obstacle is Chagas' disease reactivation (CDR), usually associated to high doses of immunosuppressants. Previous studies have suggested an association of mycophenolate mofetil with increased CDR. However, mortality predictors are unknown. To identify mortality risk factors in heart transplant patients with CD and the impact of antiproliferative regimen on survival. Retrospective study with CD patients who underwent HT between January 2004 and September 2020, under immunosuppression protocol that prioritized azathioprine and change to mycophenolate mofetil in case of rejection. We performed univariate regression to identify mortality predictors; and compared survival, rejection and evidence of CDR between who received azathioprine, mycophenolate mofetil and those who changed from azathioprine to mycophenolate mofetil after discharge ("Change" group). A p-value < 0.05 was considered statistically significant. Eighty-five patients were included, 54.1% men, median age 49 (39-57) years, and 91.8% were given priority in waiting list. Nineteen (22.4%) used azathioprine, 37 (43.5%) mycophenolate mofetil and 29 (34.1%) switched therapy; survival was not different between groups, 2.9 (1.6-5.0) x 2.9 (1.8-4.8) x 4.2 (2.0-5.0) years, respectively; p=0.4. There was no difference in rejection (42%, 73% and 59% respectively; p=0.08) or in CDR (T. cruzi positive by endomyocardial biopsy 5% x 11% x 7%; p=0.7; benznidazole use 58% x 65% x 69%; p=0.8; positive PCR for T. cruzi 20% x 68% x 42% respectively; p=0.1) rates. This retrospective study did not show difference in survival in heart transplant patients with CD receiving different antiproliferative regimens. Mycophenolate mofetil was not associated with statistically higher rates of CDR or graft rejection in this cohort. New randomized clinical trials are necessary to address this issue.

A Doença de Chagas (DC) é uma causa importante de transplante cardíaco (TC). O principal obstáculo é a reativação da DC (RDC), normalmente associada a altas doses de imunossupressores. Estudos anteriores sugeriram uma associação do micofenolato de mofetila com aumento na RDC. No entanto, preditores de mortalidade são desconhecidos. Identificar os fatores de risco de mortalidade em pacientes com DC após o TC e o impacto do regime antiproliferativo sobre a sobrevida. Estudo retrospectivo com pacientes chagásicos submetidos ao TC entre janeiro de 2004 e setembro de 2020, em protocolo de imunossupressão que priorizava o uso de azatioprina e sua mudança para micofenolato de mofetila em caso de rejeição. Realizamos regressão univariada para identificar preditores de mortalidade e comparamos sobrevida, rejeição, e evidência RDC entre os pacientes que usavam azatioprina, micofenolato de mofetila, e aqueles que mudaram de azatioprina para micofenolato (grupo "Mudança") após a alta. Um valor de p<0,05 foi considerado estatisticamente significativo. Foram incluídos 85 pacientes, 54,1% homens, idade mediana 49 (39-57) anos, e 91,8% com prioridade na lista de espera. Dezenove (22,4%) usavam azatioprina, 37 (43,5%) micofenolato de mofetila, e 29 (34,1%) trocaram a terapia; a sobrevida não foi diferente entre os grupos, 2,9 (1,6-5,0) x 2,9 (1,8-4,8) x 4,2 (2,0-5,0) anos, respectivamente; p=0,4. Não houve diferença na taxa de rejeição (42%, 73% e 59% respectivamente; p=0,08) ou de RDC (T. cruzi positiva na biópsia endomiocárdica 5% x 11% x 7%; p=0,7; uso benzonidazol 58% x 65% x 69%; p=0,8; PCR positiva para T. cruzi 20% x 68% x 42% respectivamente; p=0,1). Este estudo retrospectivo com pacientes com DC e TC não mostrou diferença na sobrevida entre os diferentes regimes antiproliferativos. O uso de micofenolato de mofetila não foi associado com taxas significativamente mais altas de RDC ou rejeição do enxerto nesta coorte. Novos ensaios randomizados são necessários para abordar essa questão.

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.

Use of sirolimus as an adjuvant therapy for kidney transplant recipients with high-risk cutaneous squamous cell carcinomas: a prospective non-randomized controlled study.

INTRODUCTION: Previous research demonstrated benefits of late conversion to mTOR inhibitors against cutaneous squamous cell carcinomas (cSCC) in kidney transplant recipients (KTR), despite of poor tolerability. This study investigated whether stepwise conversion to sirolimus monotherapy without an attack dose modified the course of disease with improved tolerability. METHODS: This prospective exploratory study included non-sensitized KTR with more than 12-months post-transplant, on continuous use of calcineurin inhibitors (CNI)-based therapy, and with poor-prognosis cSCC lesions. Incidence densities of high-risk cSCC over 3-years after conversion to sirolimus-monotherapy were compared to a non-randomized group with high-risk cSCC but unsuitable/not willing for conversion. RESULTS: Forty-four patients were included (83% male, mean age 60 ± 9.7years, 62% with skin type II, mean time after transplantation 9 ± 5.7years). There were 25 patients converted to SRL and 19 individuals kept on CNI. There was a tendency of decreasing density of incidence of all cSCC in the SRL group and increasing in the CNI group (1.49 to 1.00 lesions/patient-year and 1.74 to 2.08 lesions/patient-year, p = 0.141). The density incidence of moderately differentiated decreased significantly in the SRL group while increasing significantly in the CNI group (0.31 to 0.11 lesions/patient-year and 0.25 to 0.62 lesions/patient-year, p = 0.001). In the SRL group, there were no sirolimus discontinuations, no acute rejection episodes, and no de novo DSA formation. Renal function remained stable. CONCLUSIONS: This study suggests that sirolimus monotherapy may be useful as adjuvant therapy of high-risk cSCC in kidney transplant recipients. The conversion strategy used was well tolerated and safe regarding key mid-term transplant outcomes.

A comprehensive update of the metabolic and toxicological considerations for immunosuppressive drugs used during pancreas transplantation.

INTRODUCTION: Despite significant advancements in immunosuppressive regimens and surgical techniques, the prevalence of adverse events related to immunosuppression remains a major challenge affecting the long-term survival rates of pancreas and kidney allografts. AREAS COVERED: This article presents a comprehensive review of the literature and knowledge (Jan/2012-Feb/2023) concerning glucose metabolism disorders and nephrotoxicity associated with tacrolimus and mammalian target of rapamycin inhibitors (mTORi). Novel signaling pathways potentially implicated in these adverse events are discussed. Furthermore, we extensively examine the findings from clinical trials evaluating the efficacy and safety of tacrolimus, mTORi, and steroid minimization. EXPERT OPINION: Tacrolimus-based regimens continue to be the standard treatment following pancreas transplants. However, prolonged use of tacrolimus and mTORi may lead to hyperglycemia and nephrotoxicity. Understanding and interpreting experimental data, particularly concerning novel signaling pathways beyond calcineurin-NFAT and mTOR pathways, can offer valuable insights for therapeutic interventions to mitigate hyperglycemia and nephrotoxicity. Additionally, critically analyzing clinical trial results can identify opportunities for personalized safety-based approaches to minimize side effects. It is imperative to conduct randomized-controlled studies to assess the impact of mTORi use and steroid-free protocols on pancreatic allograft survival. Such studies will aid in tailoring treatment strategies for improved transplant outcomes.

Immunosuppression Protocols in Intestinal and Multivisceral Transplantation-A Literature Review.

BACKGROUND: Intestinal transplantation (IT) and multivisceral transplantation (MVT) are curative therapies for patients with intestinal failure and severe complications associated with total parenteral nutrition. High levels of immunosuppression are required to prevent acute cellular rejection (ACR) from the bowel. Studies regarding pre-treatment, induction, and post-transplant therapy have improved graft acceptance, reducing immunosuppression doses and infectious complications. However, the low rate of IT and MVT and the small number of specialized centers have resulted in a limited number of evidence-based immunosuppression protocols. We reviewed immunosuppression in IT and MVT to draw useful conclusions regarding the best protocol strategies for the induction, maintenance, and management of ACR. METHODS: A review was performed using the PubMed database. Articles on immunosuppression protocols in IT and MVT that addressed graft rejection, infection, or survival, published between 2006 and 2022, were selected. RESULTS: A total of 690 articles were selected. Two researchers applied the inclusion and exclusion criteria and selected 14 articles independently. For induction, thymoglobulin, alemtuzumab, and basiliximab are the most frequently used immunosuppressants for induction. Classic maintenance therapy consists of a combination of corticosteroids and tacrolimus. Methylprednisolone with an increased tacrolimus dose is used most frequently to manage ACR. Depending on the receptor response, such as thymoglobulin, infliximab, adalimumab, or bortezomib, other immunosuppressants should be considered. CONCLUSIONS: There have been great advances in IT and TMV immunosuppression. We conclude that the gold standard immunosuppressive protocol is triple therapy, comprising induction with thymoglobulin, maintenance with steroids for a few months, and tacrolimus and mycophenolate therapy. Innovative approaches for treating intestinal rejection episodes with more appropriate drugs, such as infliximab, adalimumab, or bortezomib, are necessary.

Recipient and Center Factors Associated With Immunosuppression Practice Beyond the First Year After Liver Transplantation and Impact on Outcomes.

BACKGROUND: Immunosuppression is a critical aspect of post-transplant management, yet practices at intermediate and late time points after liver transplantation (LT) are poorly characterized. METHODS: A retrospective cohort of 11 326 adult first LT alone recipients between 2007 and 2016 was identified by linking United Network for Organ Sharing transplant data to Medicare administrative claims. The immunosuppression regimen was obtained from Medicare billing claims. Factors associated with calcineurin inhibitor (CNI) monotherapy at 1-, 3-, and 5-y post-LT were investigated using mixed-effects logistic regression. Center practice heterogeneity was evaluated. The association of immunosuppression regimen (time-updating) with patient and graft survival was studied. RESULTS: CNI monotherapy was used in 51.9% at 1-y post-LT and 68.6% at 5-y post-LT. Center-specific rates ranged from 20.0%-79.9% to 15.4%-95.2%, respectively. CNI monotherapy at 1- and 3-y post-LT was less likely among Black recipients ( P = 0.027 and P = 0.015 versus White, respectively). CNI plus antimetabolite was associated with improved adjusted patient (hazard ratio, 0.59; P < 0.001) and graft (hazard ratio, 0.62; P < 0.001) survival versus CNI monotherapy. The benefit of CNI plus antimetabolite on patient and graft survival increased with older age. CONCLUSIONS: In this first longitudinal analysis of LT immunosuppression practices among Medicare beneficiaries, a CNI plus antimetabolite approach led to improved outcomes. Significant center heterogeneity in practice was observed.

Trasplante pulmonar: una perspectiva desde la inmunología / Lung transplantation: a perspective from immunology

Resumen El trasplante pulmonar implica una serie de desafíos, que como lo ha demostrado la historia, no sólo depende de un adecuado desarrollo de técnicas quirúrgicas, sino también de la comprensión de una serie de complejas interacciones inmunológicas celulares y humorales que serán las responsables del tipo de respuesta (innata y/o adquirida) fisiológica y que pudiesen desencadenar las complicaciones asociadas al trasplante (rechazo hiperagudo, agudo o crónico). Cada una de las cuales tiene su potencial prevención y/o tratamiento. El poder conocer esta serie de respuestas, permite al clínico anticiparse a algunos de estos eventos y evitar de mejor forma el daño y las consecuencias que pueden producir en los casos de trasplante pulmonar.

Lung transplantation involves a series of challenges, which as history has shown, depends not only on an adequate development of surgical techniques, but also on the understanding of a series of complex cellular and humoral immunological interactions that will be responsible for the type of physiological response (innate - acquired) and that could trigger the complications associated with transplantation (hyperacute, acute or chronic rejection). Each of which has its potential prevention and treatment. Being able to know this series of responses, allows the clinician to anticipate some of these events and to avoid in a better way the damage and the consequences that can occur in cases of lung transplantation.

Delayed Graft Function Under the Microscope: Surveillance Biopsies in Kidney Transplantation.

Delayed graft function (DGF) is a common complication of kidney transplantation and frequently leads to the necessity of surveillance biopsies. The purpose of this study is to describe the histological findings in surveillance biopsies of deceased donor kidney transplant recipients and evaluate the risk factors for graft outcomes. This is a monocentric, retrospective study including kidney transplant recipients that underwent a graft biopsy during the DGF period between January 2006 and July 2019. 356 biopsies were performed in 335 deceased donor transplant recipients. Biopsies were analyzed according to the Banff classification. The main histological findings were: acute tubular necrosis in 150 biopsies (42.1%), acute rejection in 96 biopsies (26.9%), and borderline findings in 91 biopsies (25.5%). In the multivariate analysis, recipient age (p = 0.028) and DGF duration (p = 0.005) were associated with rejection, antibody-induction with anti-thymocyte globulin (ATG) was protective (p = 0.001). The occurrence of rejection was associated with lower death-censored graft survival (log-rank; p = 0.009). Surveillance biopsies of kidney grafts experiencing DGF remain an essential tool for the care of kidney transplant recipients. The recipient's age and duration of DGF are independent risk factors for acute rejection, while antibody-induction therapy with ATG is associated with protection from its occurrence.

Desensitization using IVIG alone for living-donor kidney transplant: impact on donor-specific antibodies.

INTRODUCTION: Sensitization to human leukocyte antigen is a barrier to. Few data have been published on desensitization using polyvalent human intravenous immunoglobulin (IVIG) alone. METHODS: We retrospectively reviewed the of 45 patients with a positive complement-dependent cytotoxicity crossmatch (CDCXM) or flow cytometry crossmatch (FCXM) against living donors from January 2003 to December 2014. Of these, 12 were excluded. Patients received monthly IVIG infusions (2 g/kg) only until they had a negative T-cell and B-cell FCXM. RESULTS: During the 33 patients, 22 (66.7%) underwent living donor kidney transplantation, 7 (21.2%) received a deceased donor graft, and 4 (12.1%) did not undergo transplantation. The median class I and II panel reactive antibodies for these patients were 80.5% (range 61%-95%) and 83.0% (range 42%-94%), respectively. Patients (81.8%) had a positive T-cell and/or B-cell CDCXM and 4 (18.2%) had a positive T-cell and/or B-cell FCXM. Patients underwent transplantation after a median of 6 (range 3-16). The median donor-specific antibody mean fluorescence intensity sum was 5057 (range 2246-11,691) before and 1389 (range 934-2492) after desensitization (p = 0.0001). Mean patient follow-up time after transplantation was 60.5 (SD, 36.8) months. Nine patients (45.0%). Death-censored graft survival at 1, 3, and 5 years after transplant was 86.4, 86.4, and 79.2%, respectively and patient survival was 95.5, 95.5, and 83.7%, respectively. CONCLUSIONS: Desensitization using IVIG alone is an effective strategy, allowing successful transplantation in 87.9% of these highly sensitized patients.