Risk factors for lower renal compensation after nephrectomy: an analysis of living kidney donors in an Amazonian cohort / Fatores de risco para menor compensação renal pós-nefrectomia: análise de doadores de rim vivo em uma coorte amazônica

Abstract Introduction: Living donor kidney transplantation is considered the ideal renal replacement therapy because it has a lower complication rate and allows an efficient response to the high demand for grafts in the healthcare system. Careful selection and adequate monitoring of donors is a key element in transplantation. Individuals at greater risk of developing kidney dysfunction after nephrectomy must be identified. Objective: To identify risk factors associated with a renal compensation rate (CR) below 70% 12 months after nephrectomy. Methods: This observational retrospective longitudinal study included living kidney donors followed up at the Lower Amazon Regional Hospital between 2016 and 2022. Data related to sociodemographic variables, comorbid conditions and kidney function parameters were collected. Results: The study enrolled 32 patients. Fourteen (43.75%) had a CR < 70% 12 months after kidney donation. Logistic regression found obesity (Odds Ratio [95%CI]: 10.6 [1.7-65.2]), albuminuria (Odds Ratio [95%CI]: 2.41 [1.2-4.84]) and proteinuria (Odds Ratio [95%CI]: 1.14 [1.03-1.25]) as risk factors. Glomerular filtration rate was a protective factor (Odds Ratio [95% CI]: 0.92 [0.85-0.99]). Conclusion: Obesity, albuminuria and proteinuria adversely affected short-term renal compensation rate. Further studies are needed to uncover the prognostic implications tied to these risk factors. Our findings also supported the need for careful individualized assessment of potential donors and closer monitoring of individuals at higher risk.

Resumo Introdução: O transplante de rim de doador vivo é considerado a terapia renal substitutiva ideal por oferecer menor taxa de complicações e possibilitar uma resposta eficiente à grande demanda por enxertos no sistema de saúde. A seleção criteriosa e o acompanhamento adequado dos doadores constituem um pilar fundamental dessa modalidade terapêutica, sendo essencial a identificação dos indivíduos em maior risco de disfunção renal pós-nefrectomia. Objetivo: Identificar fatores de risco para uma Taxa de Compensação (TC) da função renal inferior a 70% 12 meses após a nefrectomia. Métodos: Estudo observacional, retrospectivo e longitudinal conduzido com doadores de rim vivo acompanhados no Hospital Regional do Baixo Amazonas entre 2016 e 2022. Foram coletados dados correspondentes a variáveis sociodemográficas, comorbidades e parâmetros de função renal. Resultados: Foram incluídos 32 pacientes na amostra final. Destes, 14 (43,75%) obtiveram TC < 70% 12 meses após a doação. A regressão logística identificou a obesidade (Odds Ratio [IC95%]: 10.6 [1.7-65.2]), albuminúria (Odds Ratio [IC95%]: 2.41 [1.2-4.84]) e proteinúria (Odds Ratio [IC95%]: 1.14 [1.03-1.25]) como fatores de risco. A taxa de filtração glomerular atuou como fator de proteção (Odds Ratio [IC95%]: 0.92 [0.85-0.99]). Conclusão: Obesidade, albuminúria e proteinúria demonstraram impacto negativo na taxa de compensação renal em curto prazo, o que reitera a necessidade de estudos acerca das implicações prognósticas desses fatores. Além disso, reforça-se a necessidade de avaliação cuidadosa e individualizada dos possíveis doadores, com acompanhamento rigoroso, especialmente para indivíduos de maior risco.

Risk assessment for hypocalcemia in therapeutic apheresis for kidney transplantation.

INTRODUCTION: The increase in the number of kidney transplants performed in the United States has been paralleled with an increase in the utilization of therapeutic apheresis (TA) for kidney transplant indications. Hypocalcemia remains a significant contributor to the adverse event in TA. The magnitude of hypocalcemia and its risk factors are scarcely discussed in literature. METHODS: This is a retrospective cohort review of adults from 18 years and above who received TA for kidney transplant-related indications from January 1, 2017 to December 31, 2022. Data extracted included basic demographics, indication for apheresis, procedure characteristics, serum ionized calcium at the mid and end of procedure and serum creatinine at the beginning of apheresis, and so forth. RESULTS: Data from 131 patients and 860 sessions of TA were analyzed. Antibody-mediated rejection (69%) and recurrent FSGS (15%) were the leading indications for TA. There were 60 (7%) TA sessions complicated by hypocalcemia. Of these, 53 (88%) occurred in the first session, 5 (8%) occurred in second session while 2 (4%) occurred in the third and subsequent sessions. Female sex, elevated serum creatinine and use of fresh frozen plasma- are the risk factors for hypocalcemia with odd's ratio of 2.34, 7.42, and 5.01, respectively. Binary logistic regression showed that elevated serum creatinine at the commencement of therapy is an independent predictor of hypocalcemia (adjusted odd's ratio = 3.31, p = 0.001). CONCLUSION: Hypocalcemia is prevalent in this study. Clinical vigilance and tailored procedure will avert adverse consequences.

Normalization of impaired glucose tolerance after kidney transplantation is associated with improved beta-cell function.

Our previous study revealed over 50% of recipients with pre-transplant impaired glucose tolerance (IGT) improved to normal glucose tolerance after kidney transplantation. However, the mechanism is unclear. We aimed to investigate whether the changes in glucose tolerance are associated with beta-cell function and insulin resistance in Japanese kidney transplant recipients with pre-transplant IGT. Of the 265 recipients who received kidney transplantation, 54 with pre-transplant IGT were included. We divided the recipients into improvement and non-improvement groups according to the change in the area under the curve for glucose obtained from the oral glucose tolerance test (OGTT). Beta-cell function was estimated by the insulin secretion sensitivity index-2 (ISSI-2) and the disposition index (DI). Insulin resistance was estimated by the Matsuda index (MI) and the homeostasis model assessment of insulin resistance (HOMA-IR). ISSI-2, DI increased significantly after transplantation in the improved group (P<0.01, P<0.05, respectively), but not in the non-improved group. ΔISSI-2 and ΔDI were significantly and positively associated with pre-transplant 60-minute OGTT plasma glucose levels (both P<0.01). There were no differences in MI or HOMA-IR between these two groups after transplantation. In recipients not on pre-transplant dialysis, a significant negative association was found between Δblood urea nitrogen (BUN) and ΔDI (correlation coefficient: -0.48, P<0.05). In pre-transplant IGT recipients, improvements in glucose tolerance after kidney transplantation were linked to improvements in beta-cell function. The higher the 60-minute OGTT plasma glucose level, the greater the improvement in post-transplant beta-cell function. Improvements in BUN after transplantation were associated with improvements in beta-cell function.

First experiences with machine learning predictions of accelerated declining eGFR slope of living kidney donors 3 years after donation.

BACKGROUND: Living kidney donors are screened pre-donation to estimate the risk of end-stage kidney disease (ESKD). We evaluate Machine Learning (ML) to predict the progression of kidney function deterioration over time using the estimated GFR (eGFR) slope as the target variable. METHODS: We included 238 living kidney donors who underwent donor nephrectomy. We divided the dataset based on the eGFR slope in the third follow-up year, resulting in 185 donors with an average eGFR slope and 53 donors with an accelerated declining eGFR-slope. We trained three Machine Learning-models (Random Forest [RF], Extreme Gradient Boosting [XG], Support Vector Machine [SVM]) and Logistic Regression (LR) for predictions. Predefined data subsets served for training to explore whether parameters of an ESKD risk score alone suffice or additional clinical and time-zero biopsy parameters enhance predictions. Machine learning-driven feature selection identified the best predictive parameters. RESULTS: None of the four models classified the eGFR slope with an AUC greater than 0.6 or an F1 score surpassing 0.41 despite training on different data subsets. Following machine learning-driven feature selection and subsequent retraining on these selected features, random forest and extreme gradient boosting outperformed other models, achieving an AUC of 0.66 and an F1 score of 0.44. After feature selection, two predictive donor attributes consistently appeared in all models: smoking-related features and glomerulitis of the Banff Lesion Score. CONCLUSIONS: Training machine learning-models with distinct predefined data subsets yielded unsatisfactory results. However, the efficacy of random forest and extreme gradient boosting improved when trained exclusively with machine learning-driven selected features, suggesting that the quality, rather than the quantity, of features is crucial for machine learning-model performance. This study offers insights into the application of emerging machine learning-techniques for the screening of living kidney donors.

A new technique for the treatment of ureteric stricture after kidney transplantation.

OBJECTIVE: To evaluate the safety and effectiveness of endoscopic treatments with Allium® metal ureteric stent (AMUS) for ureteric strictures after kidney transplantation (KT). PATIENTS AND METHODS: In a prospective manner, we gathered clinical data from 68 patients who underwent endoscopic treatments with AMUS for ureteric strictures after KT between January 2019 and March 2022. The definition of surgical success was the unobstructed drainage of the AMUS, or in cases where there was AMUS migration, occlusion or encrustation and subsequently removed, there is no worsening of renal hydronephrosis in the patient during the follow-up period. RESULTS: Based on the specific circumstances of the ureteric strictures, three distinct types of surgery were selected for treatment. The overall success rate of endoscopic treatments for ureteric strictures following KT was 90% (61/68) during a follow-up period of 1 year. Surgical complications included haematuria (18%), pain (10%), urinary tract infections (7.4%), and lower urinary tract symptoms (7.4%). The incidences of stent migration, occlusion, and encrustation were 10%, 2.9%, and 1.5%, respectively. Postoperatively, significant improvements were observed in various parameters. At 1 month after surgery, there was a notable decrease in blood creatinine levels (105.5 vs 90.4 mol/L), urea nitrogen levels (6.6 vs 5.4 mmol/L), and hydronephrosis volume (64.4 vs 43.9 mL). Additionally, the serum estimated glomerular filtration rate increased from 49.5 to 64.4 mL/min/1.73 m2. The follow-up results of patients at 1 year after surgery were similar to those observed at 1 month after surgery. CONCLUSIONS: Systemic endoscopic treatments with AMUS were found to be safe and effective for ureteric strictures after KT with short-term follow-ups. This technique offers a novel option for the treatment of post-KT strictures.

HIV and kidney transplantation in Romania: The index case.

INTRODUCTION: Human immunodeficiency virus (HIV) is no longer considered a contraindication for kidney transplantation (KT). KT management in HIV patients is a complex process with challenges, such as drug interactions between immunosuppression and antiretroviral (ARV) therapy. In our country, no KT has been performed thus far in this category of patients. CASE PRESENTATION: We present the case of a 29-year-old female patient with HIV and end-stage renal disease (ESRD) who performed a KT from a related living donor in March 2022. KT immediate evolution was favorable. No transplant-related complications were reported. HIV viral load remained undetectable and CD4+ T cells were constantly > 500 cell/ µL, during the 18 months of follow-up. The main challenge in our case was the drug interaction between the protease inhibitor-based regimen and tacrolimus. This led to tacrolimus overdose, and, subsequently, change in ARV therapy. ARV switching was performed on a regimen based on integrase inhibitor and nucleoside reverse transcriptase inhibitors. After the ARV change, the therapeutic level of tacrolimus was easily reached and maintained. Kidney graft function remained normal during follow-up, despite tacrolimus overexposure, and no rejection or anti-HLA antibodies were observed. Another challenge was related to the donor's hepatitis C virus status (positive antibodies, negative nucleic acid test). The recipient did not develop seroconversion or detectable viremia at 3-, 6-, 12- and 18-months post-KT. CONCLUSION: We reported the first case of a successful KT in an ESRD patient with HIV in Romania, in whom the post-transplant evolution was favorable.

Kidney transplantation after pelvic radiotherapy: increased morbidity?

INTRODUCTION: The impact of pelvic irradiation on kidney transplant surgery is still unclear. The main objective of our study is to evaluate the feasibility and the saftety of renal transplantation following pelvic radiotherapy. METHODS: We collected characteristics and kidney transplant data from patients with a history of pelvic cancer treated with pelvic irradiation between 2005 and 2021. These data were collected via the prospective information system "Computerized Data Validated in Transplantation" (DIVAT) and medical records. We carried out a comparative study with a non-irradiated matched control group to compare the data of intraoperative surgeries, complications reported postoperatively as well as survival of the graft and the patient. Patients were matched on age, sex, side of graft implantation, and graft rank. RESULTS: 24 patients were collected with an average age of 65, 18 patients were treated for prostatic adenocarcinoma, 4 for gynecological cancer and 2 testicular cancers. 21 patients were treated by radiotherapy, 3 by brachytherapy. 8 patients had a target dose on the iliac lymph nodes. The comparative study showed a significant difference in operative difficulty (n=15 versus n=1 p<0.01), operative duration (190min versus 149min p=0.005), occurrence of lymphocele (p=0.041). Urinary anastomosis surgical techniques were different, 83.3% of control patients had a ureterovesical anastomosis against 58.3% of patients with a history of irradiation (p=0.057) and about 29% of irradiated patients had an uretero-ureteral anastomosis. There was no other significant difference in per and postoperative criteria or survival. DISCUSSION: A history of pelvic irradiation significantly increases the technical complexity of kidney transplantation without impacting saftey and kidney graft survival.An history of Pelvic irradiation should not be a contraindication to kidney transplant.

Iguratimod ameliorates antibody-mediated rejection after renal transplant by modulating the Th17/Treg paradigm.

BACKGROUND: Iguratimod (IGU) is widely used in clinical practice due to its stable anti-inflammatory effects. Our previous studies have confirmed that the proportion of Th17/Treg balance in patients taking IGU altered significantly. This study aims to explore the role of IGU in antibody-mediated rejection (ABMR) and its potential mechanisms. METHODS: We conducted bioinformatics analysis of sequencing data from the GEO database to analyze the abundance of immune cell infiltration in transplanted kidney tissues. In vivo, IGU was intervened in a mice secondary skin transplantation model and a mice kidney transplantation ABMR model, and histological morphology of the grafts were examined by pathological staining, while relevant indicators were determined through qRT-PCR, immunohistochemistry, and enzyme-linked immunosorbent assay, observed T cell differentiation by flow cytometry, and preliminarily assessed the immunosuppressive effect of IGU. In vitro, we established Th17 and Treg cell induction and stimulation differentiation culture systems and added IGU for intervention to explore its effects on their differentiation. RESULTS: Through bioinformatics analysis, we found that Th17 and Treg may play important roles in the occurrence and development of ABMR. In vivo, we found that IGU could effectively reduce the damage caused by ABMR to the grafts, alleviate the infiltration of inflammatory cells in the graft tissues, and reduce the deposition of C4d in the grafts. Moreover, it is also found that IGU regulated the differentiation of Th17 and Treg cells in the spleen and peripheral blood and reduced the expression of IL-17A in the grafts and serum. In addition, same changes were observed in the induction and differentiation culture system of Th17 and Treg cells in vitro after the addition of IGU. CONCLUSION: IGU can inhibit the progression of ABMR by regulating the differentiation of Th17 and Treg cells, providing novel insights for optimizing clinical immunosuppressive treatment regimens.

Kidney transplant outcomes in children with simultaneous versus sequential heart-kidney transplants.

BACKGROUND: Heart transplant recipients frequently require kidney transplantation for concomitant advanced chronic kidney disease. Data on simultaneous (heart and kidney transplants performed simultaneously) versus sequential (heart transplant performed before kidney) heart-kidney transplants in children are limited. Herein, we compare kidney transplant outcomes between the two groups. METHOD: We used the Scientific Registry of Transplant Recipients to identify all pediatric (age <21 years) heart transplant recipients who also received a kidney transplant within 10 years of the heart transplant. We divided the study cohort into simultaneous heart-kidney and sequential heart-kidney recipients. We compared patient and death-censored graft survival using the Cox regression, adjusting for age at kidney transplant, sex, race, pre-transplant dialysis, donor type, and prior kidney transplant. We evaluated delayed graft function (defined as dialysis within the first week posttransplant) using logistic regression. RESULTS: Our analysis cohort included 165 recipients (86 simultaneous and 79 sequential). The incidence of delayed graft function was higher in simultaneous recipients (22.4 vs. 7.7%, p=0.017), but the difference lost statistical significance on multivariable analysis. We found no difference in patient survival (aHR 0.97; 95% CI 0.39, 2.41; p=0.95) after kidney transplant but higher death-censored kidney graft survival in sequential heart-kidney recipients compared with simultaneous heart-kidney recipients (aHR 4.26; 95% CI 1.21, 14.9; p=0.02). CONCLUSION: Sequential heart-kidney transplants are associated with higher death-censored kidney allograft survival in children compared with simultaneous heart-kidney transplants.

Parathyroidectomy: still the best choice for the management of severe secondary hyperparathyroidism / Paratireoidectomia: ainda a melhor escolha para o tratamento do hiperparatireoidismo secundário grave

Abstract Introduction: Management of secondary hyperparathyroidism (SHPT) is a challenging endeavor with several factors contruibuting to treatment failure. Calcimimetic therapy has revolutionized the management of SHPT, leading to changes in indications and appropriate timing of parathyroidectomy (PTX) around the world. Methods: We compared response rates to clinical vs. surgical approaches to SHPT in patients on maintenance dialysis (CKD 5D) and in kidney transplant patients (Ktx). A retrospective analysis of the one-year follow-up findings was carried out. CKD 5D patients were divided into 3 groups according to treatment strategy: parathyroidectomy, clinical management without cinacalcet (named standard - STD) and with cinacalcet (STD + CIN). Ktx patients were divided into 3 groups: PTX, CIN (cinacalcet use), and observation (OBS). Results: In CKD 5D we found a significant parathormone (PTH) decrease in all groups. Despite all groups had a higher PTH at baseline, we identified a more pronounced reduction in the PTX group. Regarding severe SHPT, the difference among groups was evidently wider: 31%, 14% and 80% of STD, STD + CIN, and PTX groups reached adequate PTH levels, respectively (p<0.0001). Concerning the Ktx population, although the difference was not so impressive, a higher rate of success in the PTX group was also observed. Conclusion: PTX still seems to be the best treatment choice for SHPT, especially in patients with prolonged diseases in unresourceful scenarios.

Resumo Introdução: O manejo do hiperparat-ireoidismo secundário (HPTS) é uma tarefa desafiadora com diversos fatores que contribuem para o fracasso do tratamento. A terapia calcimimética revolucionou o manejo do HPTS, levando a alterações nas indicações e no momento apropriado da paratireoidectomia (PTX) em todo o mundo. Métodos: Comparamos taxas de resposta às abordagens clínica vs. cirúrgica do HPTS em pacientes em diálise de manutenção (DRC 5D) e pacientes transplantados renais (TxR). Foi realizada uma análise retrospectiva dos achados de um ano de acompanhamento. Pacientes com DRC 5D foram divididos em 3 grupos de acordo com a estratégia de tratamento: paratireoidectomia, manejo clínico sem cinacalcete (denominado padrão - P) e com cinacalcete (P + CIN). Os pacientes com TxR foram divididos em 3 grupos: PTX, CIN (uso de cinacalcete) e observação (OBS). Resultados: Na DRC 5D, encontramos uma redução significativa do paratormônio (PTH) em todos os grupos. Apesar de todos os grupos apresentarem um PTH mais elevado no início do estudo, identificamos uma redução mais acentuada no grupo PTX. Com relação ao HPTS grave, a diferença entre os grupos foi evidentemente maior: 31%, 14% e 80% dos grupos P, P + CIN e PTX atingiram níveis adequados de PTH, respectivamente (p< 0,0001). Com relação à população TxR, embora a diferença não tenha sido tão impressionante, também foi observada uma taxa maior de sucesso no grupo PTX. Conclusão: A PTX ainda parece ser a melhor escolha de tratamento para o HPTS, especialmente em pacientes com doenças prolongadas em cenários sem recursos.

Pregnancy after kidney transplantation: 40 years single-center experience / Gestação após transplante renal: 40 anos de experiência em centro único

Abstract Background: Kidney transplantation (KT) improves quality of life, including fertility recovery. Objective: to describe outcomes of post-KT pregnancy and long-term patient and graft survival compared to a matched control group of female KT recipients who did not conceive. Methods: retrospective single-center case-control study with female KT recipients from 1977 to 2016, followed-up until 2019. Results: there were 1,253 female KT patients of childbearing age in the study period: 78 (6.2%) pregnant women (cases), with a total of 97 gestations. The median time from KT to conception was 53.0 (21.5 - 91.0) months. Abortion rate was 41% (spontaneous 21.6%, therapeutic 19.6%), preterm delivery, 32%, and at term delivery, 24%. Pre-eclampsia (PE) occurred in 42% of pregnancies that reached at least 20 weeks. The presence of 2 or more risk factors for poor pregnancy outcomes was significantly associated with abortions [OR 3.33 (95%CI 1.43 - 7.75), p = 0.007] and with kidney graft loss in 2 years. The matched control group of 78 female KT patients was comparable on baseline creatinine [1.2 (1.0 - 1.5) mg/dL in both groups, p = 0.95] and urine protein-to-creatinine ratio (UPCR) [0.27 (0.15 - 0.44) vs. 0.24 (0.02 - 0.30), p = 0.06]. Graft survival was higher in cases than in controls in 5 years (85.6% vs 71.5%, p = 0.012) and 10 years (71.9% vs 55.0%, p = 0.012) of follow-up. Conclusion: pregnancy can be successful after KT, but there are high rates of abortions and preterm deliveries. Pre-conception counseling is necessary, and should include ethical aspects.

Resumo Histórico: Transplante renal (TR) melhora qualidade de vida, incluindo recuperação da fertilidade. Objetivo: descrever desfechos gestacionais pós-TR e sobrevida de longo prazo da paciente e do enxerto renal comparada a um grupo controle pareado de receptoras de TR que não conceberam. Métodos: estudo retrospectivo caso-controle com receptoras de TR de 1977 a 2016, acompanhadas até 2019. Resultados: foram identificadas 1.253 receptoras de TR em idade fértil no período do estudo: 78 (6,2%) gestantes (casos), total de 97 gestações. Tempo mediano entre TR até concepção foi 53,0 (21,5 - 91,0) meses. Taxa de aborto foi 41% (espontâneo 21,6%, terapêutico 19,6%), parto prematuro, 32%, e a termo, 24%. Pré-eclâmpsia (PE) ocorreu em 42% das gestações que alcançaram pelo menos 20 semanas. Presença de 2 ou mais fatores de risco para desfechos gestacionais desfavoráveis foi significativamente associada a abortos [OR 3,33 (IC95% 1,43 - 7,75), p = 0,007] e perda de enxerto renal em 2 anos. O grupo controle de 78 mulheres com TR foi comparável na creatinina basal [1,2 (1,0 - 1,5) mg/dL nos dois grupos, p = 0,95] e na relação proteína/creatinina urinária (RPCU) [0,27 (0,15 - 0,44) vs. 0,24 (0,02 - 0,30), p = 0,06]. Sobrevida do enxerto foi maior nos casos que nos controles em 5 anos (85,6% vs. 71,5%, p = 0,012) e 10 anos (71,9% vs. 55,0%, p = 0,012) de acompanhamento. Conclusão: a gestação pode ser bem-sucedida após TR, mas existem altas taxas de abortos e partos prematuros. Aconselhamento pré-concepção é necessário e deve incluir aspectos éticos.

Relationship of hemoglobin levels with outcomes in deceased donor kidney transplant: a retrospective cohort study / Relação dos níveis de hemoglobina com desfechos em transplante renal de doador falecido: um estudo de coorte retrospectivo

ABSTRACT Introduction: Anemia is frequent in patients undergoing replacement therapy for kidney failure. Anemia in the pre- and post-transplantation period might be related to kidney transplant outcomes. The current study therefore sought to assess the relationship between anemia, delayed allograft function (DGF), chronic kidney allograft dysfunction (CAD), and death from any cause following kidney transplantation from a deceased donor. Methods: This was a retrospective study with 206 kidney transplant patients of deceased donors. We analyzed deceased donors' and kidney transplant patients' demographic data. Moreover, we compared biochemical parameters, anemia status, and medicines between DGF and non-DGF groups. Afterward, we performed a multivariate analysis. We also evaluated outcomes, such as CAD within one year and death in ten years. Results: We observed a lower frequency of pre-transplant hemoglobin concentration (Hb) but higher frequency of donor-serum creatinine and red blood transfusion within one week after transplantation in the group with DGF. In addition, there was an independent association between Hb concentration before transplantation and DGF [OR 0.252, 95%CI: 0.159-0.401; p < 0.001]. There was also an association between Hb concentration after six months of kidney transplantation and both CAD [OR 0.798, 95% CI: 0.687-0.926; p = 0.003] and death from any cause. Conclusion: An association was found between pre-transplantation anemia and DGF and between anemia six months after transplantation and both CAD and death by any cause. Thus, anemia before or after transplantation affects the outcomes for patients who have undergone kidney transplantation from a deceased donor.

RESUMO Introdução: A anemia é frequente em pacientes submetidos à terapia substitutiva para insuficiência renal. A anemia nos períodos pré e pós-transplante pode estar relacionada aos desfechos do transplante renal. Portanto, o presente estudo buscou avaliar a relação entre anemia, função retardada do enxerto (FRE), disfunção crônica do enxerto renal (DCE) e óbito por qualquer causa após transplante renal de doador falecido. Métodos: Este foi um estudo retrospectivo com 206 pacientes transplantados renais de doadores falecidos. Analisamos dados demográficos de doadores falecidos e pacientes transplantados renais. Além disso, comparamos parâmetros bioquímicos, status de anemia e medicamentos entre os grupos FRE e não-FRE. Posteriormente, realizamos uma análise multivariada. Também avaliamos desfechos, como DCE em um ano e óbito em dez anos. Resultados: Observamos menor frequência de concentração de hemoglobina (Hb) pré-transplante, mas maior frequência de creatinina sérica do doador e transfusão de hemácias no período de uma semana após o transplante no grupo FRE. Além disso, houve associação independente entre a concentração de Hb antes do transplante e a FRE [OR 0,252; IC 95%: 0,159-0,401; p < 0,001]. Houve também associação entre a concentração de Hb após seis meses de transplante renal e ambos, DCE [OR 0,798; IC95%: 0,687-0,926; p = 0,003] e óbito por qualquer causa. Conclusão: Encontrou-se uma associação entre anemia pré-transplante e FRE e entre anemia seis meses após o transplante e ambos, DCE e óbito por qualquer causa. Assim, a anemia antes ou após o transplante afeta os desfechos de pacientes que foram submetidos a transplante renal de doador falecido.

Removing the physician from the equation: Patient-controlled, home-based therapeutic drug self-monitoring of tacrolimus.

The dosing of tacrolimus, which forms the backbone of immunosuppressive therapy after kidney transplantation, is complex. This is due to its variable pharmacokinetics (both between and within individual patients), narrow therapeutic index, and the severe consequences of over- and underexposure, which may cause toxicity and rejection, respectively. Tacrolimus is, therefore, routinely dosed by means of therapeutic drug monitoring (TDM). TDM is performed for as long as the transplant functions and frequent and often lifelong sampling is therefore the rule. This puts a significant burden on patients and transplant professionals and is associated with high healthcare-associated costs. Furthermore, by its very nature, TDM is reactive and has no predictive power. Finally, the current practice of TDM does not foresee in an active role for patients themselves. Rather, the physician or pharmacist prescribes the next tacrolimus dose after obtaining the concentration measurement test results. In this article, we propose a strategy of patient-controlled, home-based, self-TDM of the immunosuppressant tacrolimus after transplantation. We argue that with the combined use of population tacrolimus pharmacokinetic models, home-based sampling by means of dried blood spotting and implementation of telemedicine, this may become a feasible approach in the near future.

The Gut Microbiome and Symptom Burden After Kidney Transplantation: An Overview and Research Opportunities.

Many kidney transplant recipients continue to experience high symptom burden despite restoration of kidney function. High symptom burden is a significant driver of quality of life. In the post-transplant setting, high symptom burden has been linked to negative outcomes including medication non-adherence, allograft rejection, graft loss, and even mortality. Symbiotic bacteria (microbiota) in the human gastrointestinal tract critically interact with the immune, endocrine, and neurological systems to maintain homeostasis of the host. The gut microbiome has been proposed as an underlying mechanism mediating symptoms in several chronic medical conditions including irritable bowel syndrome, chronic fatigue syndrome, fibromyalgia, and psychoneurological disorders via the gut-brain-microbiota axis, a bidirectional signaling pathway between the enteric and central nervous system. Post-transplant exposure to antibiotics, antivirals, and immunosuppressant medications results in significant alterations in gut microbiota community composition and function, which in turn alter these commensal microorganisms' protective effects. This overview will discuss the current state of the science on the effects of the gut microbiome on symptom burden in kidney transplantation and future directions to guide this field of study.

Endovascular intervention with intravascular ultrasound guidance of very early dissection complication in transplant renal artery: a case report and literature review.

Background: Transplant renal artery dissection (TRAD) is a rare and serious event that can cause allograft dysfunction and eventually graft loss. Most cases are managed by operative repair. We report a case of TRAD in the early postoperative period, which was successfully managed with intravascular ultrasound-assisted endovascular intervention. Case presentation: A 38-year-old man underwent HLA-compatible living kidney transplantation. The allograft had one renal artery and vein, which were anastomosed to the internal iliac artery and external iliac vein, respectively. Doppler ultrasonography performed a day after the operation showed an increase in systolic blood velocity, with no observed urine output and raising a suspicion of arterial anastomotic stenosis. Angiography showed a donor renal artery dissection distal to the moderately stenosed anastomosis site with calcified atherosclerotic plaque confirmed by IVUS. The transplant renal artery lesion was intervened with a stent. After the intervention, Doppler US revealed that the blood flow of the renal artery was adequate without an increase in the systolic blood velocity. Urine output gradually returned after 3 weeks, and serum creatinine level was normalized after 2 months. Conclusions: Transplant recipients commonly have atherosclerosis and hypertension, which are risk factors for arterial dissection. Our case showed that endovascular intervention can replace surgery to repair very early vascular complications such as dissection and help patients avoid high-risk operations. Early diagnosis and IVUS-assisted intervention with experienced interventionists can save allograft dysfunction.

A multimodal aftercare intervention improves the outcome after kidney transplantation - results of the KTx360° aftercare program using claims data.

Background: The after-care treatment project KTx360° aimed to reduce graft failure and mortality after kidney transplantation (KTx). Methods: The study was conducted in the study centers Hannover, Erlangen and Hannoversch Muenden from May 2017 to October 2020 under the trial registration ISRCTN29416382. The program provided a multimodal aftercare program including specialized case management, telemedicine support, psychological and exercise assessments, and interventions. For the analysis of graft failure, which was defined as death, re-transplantation or start of long-term dialysis, we used longitudinal claims data from participating statutory health insurances (SHI) which enabled us to compare participants with controls. To balance covariate distributions between these nonrandomized groups we used propensity score methodology, in particular the inverse probability of treatment weighting (IPTW) approach. Findings: In total, 930 adult participants were recruited at three different transplant centres in Germany, of whom 320 were incident (enrolled within the first year after KTx) and 610 prevalent (enrolled >1 year after KTx) patients. Due to differences in the availability of the claims data, the claims data of 411 participants and 418 controls could be used for the analyses. In the prevalent group we detected a significantly lower risk for graft failure in the study participants compared to the matched controls (HR = 0.13, 95% CI = 0.04-0.39, p = 0.005, n = 389 observations), whereas this difference could not be detected in the incident group (HR = 0.92, 95% CI = 0.54-1.56, p = 0.837, n = 440 observations). Interpretation: Our findings suggest that a multimodal and multidisciplinary aftercare intervention can significantly improve outcome after KTx, specifically in patients later after KTx. For evaluation of effects on these outcome parameters in patients enrolled within the first year after transplantation longer observation times are necessary. Funding: The study was funded by the Global Innovation fund of the Joint Federal Committee of the Federal Republic of Germany, grant number 01NVF16009.

Kidney Transplantation in ≤15 kg Children: Outcomes and Prognostic Indicators-A Review of the Organ Procurement and Transplantation Database.

BACKGROUND: Approximately 2500 pediatric patients are awaiting kidney transplantation in the United States, with <5% comprising those ≤15 kg. Transplant in this cohort is often delayed by center-based growth parameters, often necessitating transplantation after the initiation of dialysis. Furthermore, prognostication remains somewhat ambiguous. In this report, we scrutinize the Organ Procurement and Transplantation Network (OPTN) data from 2001 to 2021 to help better understand specific variables impacting graft and patient outcomes in these children. METHODS: The OPTN kidney transplant dataset from 2001 to 2021 was analyzed. Inclusion criteria included age <18 years, weight ≤15 kg, and recipient of primary living donor kidney transplantation (LDKT) or deceased donor kidney transplantation (DDKT). Patient and graft survival probabilities were calculated using the Kaplan-Meier method. The Cox proportional hazards model was used to calculate hazard ratio (HR) and identify variables significantly associated with patient and graft survival. RESULTS: Two thousand one hundred sixty-eight pediatric transplant recipients met inclusion criteria. Patient survival at 1 and 3 years was 98% and 97%, respectively. Graft survival at 1 and 3 years was 95% and 92%, respectively. Dialysis was the sole significant variable impacting both patient and graft survival. Graft survival was further impacted by transplant era, recipient gender and ethnicity, and donor type. Infants transplanted at Age 1 had better graft survival compared with older children, and nephrotic syndrome was likewise associated with a better prognosis. CONCLUSION: Pediatric kidney transplantation is highly successful. The balance between preemptive transplantation, medical optimization, and satisfactory technical parameters seems to suggest a "Goldilocks zone" for many children, favoring transplantation between 1 and 2 years of age.

Positive Long-Term Outcome of Kidney Allocation via Acceptable Mismatch Program in Highly Sensitized Patients.

Introduction: Eurotransplant established the acceptable mismatch (AM) program to facilitate timely kidney transplantations of highly sensitized patients, but long-term granular clinical and immunological outcomes regarding overall graft survival and de novo DSA (dnDSA) formation are still intensively researched. The right choice of induction therapy in patients with differing immunological risk is not conclusively determined, as well as the impact of human leukocyte antigen (HLA) epitope matching on dnDSA formation. Methods: This monocentric, retrospective study analyzed 94 patients transplanted within the AM program between 2000 and 2019 compared to case-control matched cohorts of non- (PRA 0-5%; PRA-0) and intermediately sensitized (PRA 6-84%; PRA-6/84) patients transplanted through Eurotransplant Kidney Allocation System. Results: Estimated 10-year overall graft survival between the PRA-0 and AM cohorts was similar, whereas PRA-6/84 was significantly disadvantageous compared to PRA-0. Estimated 10-year incidence of antibody-mediated rejection rates was significantly lower in the PRA-0 group compared to AM and PRA-6/84 groups. Compared to the AM group, estimated incidence of de novo donor-specific antibody (dnDSA) was significantly lower in PRA-0 patients, with no differences between the AM and PRA-6/84 cohorts. The PRA-6/84 cohort was the only subgroup in which interleukin-2 receptor antagonist (IL2RA) induction was associated with longer overall graft survival, patient survival, and graft survival compared to depleting induction (ATG or OKT3). Broad HLA-A, -B, -DR mismatches (mmABDR) and HLA epitope mismatches determined by Eplets and PIRCHE-II were predictive for dnDSA formation in the total cohort, and the AM subgroup. Discussion: The high efforts expended on AM patients are justified to allow timely organ transplantation with acceptable risk profile and non-inferior outcomes. IL2RA induction in intermediately sensitized patients is associated with superior overall graft survival, patient survival, and graft survival compared to ATG/OKT3 induction, without negative effects on rejection episodes or dnDSA formation. In silico epitope matching might further help reduce dnDSA formation, particularly in high-risk AM patients.

Transplantation for type 1 diabetes: radiologist's primer on islet, pancreas and pancreas-kidney transplantation imaging.

Whole-organ pancreas, pancreatic-kidney and islet transplantation are surgical therapeutic options for the treatment of type 1 diabetes. They can enable effective glycemic control, improve quality of life and delay/reduce the secondary complications of type 1 diabetes mellitus. Radiologists are integral members of the multidisciplinary transplantation team involved in these procedures, with multimodality imaging serving as the mainstay for early recognition and management of transplant related complications. This review highlights the transplantation procedures available for patients with type 1 Diabetes Mellitus with a focus on the imaging appearance of transplantation-related complications.

BK polyomavirus DNAemia, allograft rejection, and de novo donor-specific antibodies after lowering target tacrolimus levels in pediatric kidney transplant recipients.

BACKGROUND: BK polyomavirus (BKV) DNAemia is a challenging infectious complication after kidney transplant (KT). Reduction of immunosuppression is the mainstay of management, and tacrolimus is often the first immunosuppressive medication adjusted upon the diagnosis of BKV DNAemia. This study aimed to evaluate the impact of a new institutional protocol with lower target tacrolimus levels on BKV DNAemia, allograft rejection, and de novo donor-specific antibodies (dnDSA) among pediatric KT recipients. METHODS: We conducted a retrospective chart review of all KT episodes between January 2013 and December 2018. The new protocol with lower target tacrolimus levels was implemented in March 2015. One hundred twenty-seven patients were included in primary analysis. All patients received induction with basiliximab and methylprednisolone and were maintained on a steroid-based immunosuppressive regimen. RESULTS: In the post-intervention cohort, cumulative incidence of BKV DNAemia at 100 days (13.4% vs. 17.8%, p = .605) and 18 months post-KT (34.1% vs. 26.7%, p = .504) was not significantly different from the pre-intervention cohort. Biopsy-proven rejection rate did not change. However, we observed a trend toward earlier development of dnDSA in the post-intervention cohort using the Kaplan-Meier survival analysis (log-rank p = .06). Younger recipient age at the time of transplant was found to slightly increase the risk of BKV DNAemia (OR: 1.09, 95% CI [1.01, 1.16], p = .024). There was an association between BKV DNAemia and biopsy-proven rejection of any type (adjustedOR: 2.77, 95% CI [1.26, 6.23], p = .012), especially acute T-cell-mediated rejection grade 1A and above (adjustedOR: 2.95, 95% CI [1.06, 8.30], p = .037), after adjusted for recipient age at the time of transplant. CONCLUSIONS: Targeting lower tacrolimus levels did not decrease the incidence of BKV DNAemia within 100 days or 18 months post-KT, nor did it increase the risk of biopsy-proven rejection among pediatric KT recipients in our center. However, there was a trend toward earlier development of dnDSA, which may portend worse long-term graft outcome post-KT. Our findings highlight the need for individualized immunosuppressive regimens based on immunologic and infectious risk factors and the importance of implementing innovative biomarkers to guide therapy and improve outcomes.