Estudio experimental aleatorizado sobre la eficacia de la preservación renal hipotérmica en máquina con suplementación de oxígeno

Introducción Hasta la fecha, la eficacia y la seguridad del empleo de altas concentraciones de oxígeno (O2) durante la perfusión hipotérmica en máquina (PHM) no han sido establecidos. En este estudio se investiga el impacto de la administración de altas concentraciones de O2 durante la PHM en un modelo porcino de donación en asistolia (DA), tanto en términos de función renal como sus efectos metabólicos y bioquímicos. Material y Métodos Estudio de cohorte prospectivo aleatorizado y no ciego en un modelo porcino de autotrasplante que imita las condiciones de la DA de tipo III de Maastricht, en condiciones de PHM con suplemento de oxígeno (PHMO) comparadas con la PHM sin oxígeno (PHM) en el dispositivo LifePort®. El objetivo primario fue la función renal post-trasplante, mientras que los objetivos secundarios fueron los cambios en la dinámica de la perfusión, la lesión celular medida por los niveles de lactato deshidrogenasa (LDH) y lactato en el líquido de preservación, la peroxidación lipídica en las biopsias renales, la transición epitelio-mesenquimal (TEM) y la expresión de genes oxidativos en los cultivos celulares, la generación de ATP medida por el test SeaHorse en los cultivos celulares, la expresión de miRNA en la solución de preservación y por último el examen histológico. Resultados La generación de ATP y el estrés oxidativo, medidos por la peroxidación lipídica, aumentaron simultáneamente tras la isquemia caliente en el grupo PHMO. La PHMO no mostró un efecto beneficioso significativo sobre la función renal o la supervivencia de los animales. Se observó un claro aumento de la peroxidación lipídica en el grupo PHMO, que también dio lugar a una mayor expresión de los genes responsables de las enzimas antioxidantes superóxido-dismutasa-1 (SOD-1) y catalasa. La disfunción de la cadena respiratoria se mantuvo en el grupo PHMO con una disminución de la producción de ATP, un aumento de la fuga de protones y una disminución de la reserva respiratoria. En cuanto a la TEM, también se observó un aumento de la expresión de los genes de vimentina, fibronectina y colágeno en el grupo PHMO. Por último, se modificaron significativamente los niveles de expresión de miR-101 y miR-126, relacionados con las funciones características del epitelio tubular. Conclusiones Aunque se observó una tendencia hacia una mejor función renal y supervivencia en el grupo PHMO, su estudio metabólico reveló una menor eficiencia de la cadena respiratoria y un incremento del estrés oxidativo que se tradujeron en un aumento de la expresión de genes de TEM, lo que podría conducir a un aumento de la fibrosis renal. El diferente perfil de miRNA asociado a la PHMO podría ser expresión de un diferente metabolismo celular subyacente. Todo ello hace que, en la actualidad, la PHMO no pueda ser considerada una práctica estándar y su papel en la preservación renal deba ser aclarado

Evaluation of predictive factors for i-CLARAS (intraoperative complications in laparoscopic renal and adrenal surgery): a multicentre international retrospective cohort study

The laparoscopic approach represents the standard of treatment for renal and adrenal diseases, and its use is increasing even outside referral centres. Although most procedures are routinely performed, intraoperative complications do not occur, and the rate and predictive factors of these complications have not been established. The aim of this study was to evaluate the incidence and type of intraoperative complications and to identify predictive factors in patients undergoing laparoscopic renal and adrenal surgery. This was a cohort, multicentre, international retrospective study. Patients who underwent laparoscopic renal and adrenal surgeries between April 2017 and March 2022 were included in the study. Bivariate analysis was performed using contingency tables and the χ2 test for independent samples to compare qualitative variables and the T test and Mood test for continuous variables. Multivariate analysis was performed using a logistic regression model to obtain adjusted odds ratios. A total of 2374 patients were included in the study. Intraoperative complications were reported for 8.09% of patients who underwent renal surgery, with the most common complications reported being hollow viscus and vascular complications, and for 6.75% of patients who underwent adrenal surgery, with the most common complication reported being parenchymatous viscous complications. Multivariate analysis revealed that both adrenal and renal surgery radiological preoperative factors, such as invasive features during adrenalectomy and the RENAL score during nephrectomy, are predictive factors of intraoperative complications. In contrast to existing data, surgeon experience was not associated with a reduction in the incidence of perioperative complications

The Usefulness of Contrast-Enhanced Ultrasound in the Assessment of Early Kidney Transplant Function and Complications

Objectives: The routine diagnostic method for assessment of renal graft dysfunction is Doppler ultrasound. However, contrast-enhanced ultrasound (CEUS) may provide more information about parenchymal flow and vascular status of kidney allografts. The aim of the study was to assess the effectiveness of CEUS in the immediate post-transplant period, focusing on acute vascular complications. A brief review of available literature and a report of our initial experience is made. Material and methods: 15 kidney transplant (KT) cases with clinical suspicion of acute surgical complication were assessed with CEUS and conventional Doppler ultrasound (US). In addition, bibliographic review was conducted through PubMed, Embase, and ClinicalKey databases. Results: 10% of KT underwent CEUS, useful for detecting vascular complication or cortical necrosis in 4 (26%) and exclude them in 74%. Grafts with acute vascular complications have a delayed contrast-enhancement with peak intensity lower than normal kidneys. Perfusion defects can be clearly observed and the imaging of cortical necrosis is pathognomonic. Conclusions: CEUS is a useful tool in the characterization of renal graft dysfunction with special interest on acute vascular complications after renal transplant. It is a feasible technique for quantitative analysis of kidney perfusion, which provides information on renal tissue microcirculation and regional parenchymal flow. Exploration could be done by a urologist at the patient’s bedside while avoiding iodinated contrast

Kidney Autotransplantation in the Management of Residual Retroperitoneal Mass in a Germ Cell Tumor

The main indication for kidney autotransplantation is ureteric disease, although it is also performed to treat renovascular diseases or neoplasms, such as complex intrasinusal kidney tumors or in patients with a solitary kidney. Only a few cases of kidney autotransplantation in the context of resection of complex retroperitoneal masses have been reported in the literature.[Case Presentation] We report the case of a 26-year-old man with history of nonseminomatous germ cell tumor who had undergone a left radical orchiectomy 3 months earlier. Follow-up computed tomography revealed a residual retroperitoneal postchemotherapy mass involving the renal hilum. It was surgically removed via en bloc resection and bench ex vivo nephron-sparing surgery, and subsequently autotransplantation, thereby avoiding the necessity of nephrectomy and the resulting risk of chronic kidney disease. The pathology of the excised specimen demonstrated mixed germ cell tumor, composed of immature teratoma and yolk sac tumor, and confirmed tumor-free margins.[Conclusions] This technique should be taken into account in selected patients as an alternative to radical nephrectomy when a retroperitoneal tumor is unresectable using standard surgical techniques or when a radical nephrectomy is considered, especially in patients with chronic kidney disease or solitary kidney, or in young patients who will potentially need nephrotoxic chemotherapy.Peer reviewe

Kidney Autotransplantation and Orthotopic Kidney Transplantation: Two Different Approaches for Complex Cases

Introduction. Transplantation surgery teams often have to face complex cases. In certain circumstances, such as occlusion of the iliac vessels or prior pelvic surgery, heterotopic kidney transplantation may not be feasible and orthotopic kidney transplantation (OKT) could be a good alternative. Kidney autotransplantation (KAT) has been described as a potential treatment for complex renovascular, ureteral, or neoplastic conditions. There are scarce data regarding the complications and outcomes of these procedures; therefore, we present our experience. Materials and Methods. We retrospectively analysed the medical records of both 21 patients who had received OKT and 19 patients who underwent KAT between 1993 and 2020. We collected demographic features and data regarding surgical technique, complications, and graft outcomes. Kidney graft survival was calculated using Kaplan–Meier survival analysis. Results. Regarding OKT, in 15 (71.43%) cases, it was the first kidney transplantation. The most common indication was the unsuitable iliac region due to vascular abnormalities (57.14%). The early postoperative complication rate was high (66.67%), with 23.81% of Clavien grade 3b complications. During the follow-up period (mean 5.76 -SD 6.15- years), we detected 9 (42.85%) graft losses. At 1 year, the survival rate was 84.9%. Concerning KAT, the most frequent indication was ureteral pathology (52.63%), followed by vascular lesions (42.11%). The overall early complication rate was 42.11%. During the follow-up period (mean of 4.47 years), 4 (15.79%) graft losses were reported. Conclusions. Although OKT and KAT have high complication rates, these techniques can be considered as two valuable approaches for complex cases, in the absence of other therapeutic options