Oxygenated versus non-oxygenated flush out during deceased donor liver procurement: The first proof-of-concept study in humans.

BACKGROUND: Liver transplantation is used for treating end-stage liver disease, fulminant hepatitis, and oncological malignancies and organ shortage is a major limiting factor worldwide. The use of grafts based on extended donor criteria have become internationally accepted. Oxygenated machine perfusion technologies are the most recent advances in organ transplantation; however, it is only applied after a period of cold ischemia. Due to its high cost, we aimed to use a novel device, OxyFlush®, based on oxygenation of the preservation solution, applied during liver procurement targeting the maintenance of ATP during static cold storage (SCS). METHODS: Twenty patients were randomly assigned to the OxyFlush or control group based on a 1:1 ratio. In the OxyFlush group, the perfusion solution was oxygenated with OxyFlush® device while the control group received a non-oxygenated solution. Liver and the common bile duct (CBD) biopsies were obtained at three different time points. The first was at the beginning of the procedure, the second during organ preparation, and the third after total liver reperfusion. Biopsies were analyzed, and adenosine triphosphate (ATP) levels and histological scores of the liver parenchyma and CBD were assessed. Postoperative laboratory tests were performed. RESULTS: OxyFlush® was able to maintain ATP levels during SCS and improved the damage caused by the lack of oxygen in the CBD. However, OxyFlush® did not affect laboratory test results and histological findings of the parenchyma. CONCLUSION: We present a novel low-cost device that is feasible and could represent a valuable tool in organ preservation during SCS.

Extracellular Vesicles as a Therapeutic Tool for Kidney Disease: Current Advances and Perspectives.

Extracellular vesicles (EVs) have been described as important mediators of cell communication, regulating several physiological processes, including tissue recovery and regeneration. In the kidneys, EVs derived from stem cells have been shown to support tissue recovery in diverse disease models and have been considered an interesting alternative to cell therapy. For this purpose, however, several challenges remain to be overcome, such as the requirement of a high number of EVs for human therapy and the need for optimization of techniques for their isolation and characterization. Moreover, the kidney's complexity and the pathological process to be treated require that EVs present a heterogeneous group of molecules to be delivered. In this review, we discuss the recent advances in the use of EVs as a therapeutic tool for kidney diseases. Moreover, we give an overview of the new technologies applied to improve EVs' efficacy, such as novel methods of EV production and isolation by means of bioreactors and microfluidics, bioengineering the EV content and the use of alternative cell sources, including kidney organoids, to support their transfer to clinical applications.

URGENT LIVER RETRANSPLANTATION DUE TO TRANSMISSION OF INTRAHEPATIC CHOLANGIOCARCINOMA BY DONOR: THE FIRST REPORT IN THE LITERATURE.

BACKGROUND: Liver transplantation represents the best therapeutic modality in end-stage chronic liver disease, severe acute hepatitis, and selected cases of liver tumors. AIMS: To describe a double retransplant in a male patient diagnosed with Crohn's disease and complicated with primary sclerosing cholangitis, severe portal hypertension, and cholangiocarcinoma diagnosed in the transplanted liver. METHODS: A 48-year-old male patient diagnosed with Crohn's disease 25 years ago, complicated with primary sclerosing cholangitis and severe portal hypertension. He underwent a liver transplantation in 2018 due to secondary biliary cirrhosis. In 2021, a primary sclerosing cholangitis recurrence was diagnosed and a liver retransplantation was indicated. Recipient's hepatectomy was very difficult by reason of complex portal vein thrombosis requiring extensive thromboendovenectomy. Intraoperative ultrasound with liver doppler evaluation was performed. Two suspicious nodules were incidentally diagnosed in the donor's liver and immediately removed for anatomopathological evaluation. RESULTS: After pathological confirmation of carcinoma, probable cholangiocarcinoma, at frozen section, the patient was re-listed as national priority and a new liver transplantation was performed within 24 hours. The patient was discharged after 2 weeks. CONCLUSIONS: The screening for neoplasms in donated organs should be part of our strict daily diagnostic arsenal. Moreover, we argue that, for the benefit of an adequate diagnosis and the feasibility of a safer procedure, the adoption of imaging tests routine for the liver donor is essential, allowing a reduction of the costs and some potential risks of liver transplant procedure.

An experience on living donor liver transplantation for colorectal liver metastasis in south america: a new era in transplant oncology / Experiência de transplante de fígado para metástase colorretal na américa do sul: uma nova era em transplante oncológico

ABSTRACT BACKGROUND: Complete surgical resection is the treatment of choice for patients with liver metastases, but in some patients, it is not possible to obtain a complete R0 resection. Moreover, the recurrence rate is up to 75% after three years. After the experience of the Oslo group with cadaveric liver transplant, some centers are starting their experience with liver transplant for colorectal liver metastasis. AIMS: To present our initial experience with living donor liver transplant for colorectal liver metastasis. METHODS: From 2019 to 2022, four liver transplants were performed in patients with colorectal liver metastases according to the Oslo criteria. RESULTS: Four patients underwent living donor liver transplants, male/female ratio was 3:1, mean age 52.5 (42-68 years). All patients were included in Oslo criteria for liver transplant. Two patients had already been submitted to liver resection. The decision for liver transplant occurred after discussion with a multidisciplinary team. Three patients recurred after the procedure and the patient number 3 died after chemotherapy. CONCLUSIONS: Living donor liver transplant is a viable treatment option for colorectal liver metastasis in Brazil, due to a shortage of donors.

RESUMO RACIONAL: A ressecção cirúrgica completa é o tratamento de escolha para pacientes com metástases hepáticas, mas em alguns pacientes não é possível obter uma completa ressecção R0. Além disso, a taxa de recorrência é de até 75% após 3 anos. Após a experiência do grupo de Oslo com transplante hepático cadavérico, alguns centros estão iniciando sua experiência com transplante hepático para metástase hepática colorretal. OBJETIVOS: Apresentar a experiência inicial com transplante de fígado de doador vivo para metástase hepática colorretal. MÉTODOS: De 2019 a 2022, foram quatro transplantes hepáticos em pacientes com metástases hepáticas colorretais, de acordo com os critérios de Oslo. RESULTADOS: Quatro pacientes foram submetidos a transplante hepático de doador vivo, a relação homem/mulher de 3:1, a idade média foi de 52,5 (42-68 anos). Todos os pacientes foram incluídos nos critérios de Oslo para transplante de fígado. Dois pacientes já haviam sido submetidos à ressecção hepática. A decisão pelo transplante hepático ocorreu após discussão com equipe multidisciplinar. Três pacientes recidivaram após o procedimento e o paciente número 3 morreu após a quimioterapia. CONCLUSÕES: O transplante de fígado com doador vivo é uma opção viável de tratamento para metástase hepática colorretal no Brasil, devido à escassez de doadores.

Urgent liver retransplantation due to transmission of intrahepatic cholangiocarcinoma by donor: the first report in the literature / Retransplante de fígado urgente devido à transmissão de colangiocarcinoma intra-hepático pelo doador: o primeiro relato da literatura

ABSTRACT BACKGROUND: Liver transplantation represents the best therapeutic modality in end-stage chronic liver disease, severe acute hepatitis, and selected cases of liver tumors. AIMS: To describe a double retransplant in a male patient diagnosed with Crohn's disease and complicated with primary sclerosing cholangitis, severe portal hypertension, and cholangiocarcinoma diagnosed in the transplanted liver. METHODS: A 48-year-old male patient diagnosed with Crohn's disease 25 years ago, complicated with primary sclerosing cholangitis and severe portal hypertension. He underwent a liver transplantation in 2018 due to secondary biliary cirrhosis. In 2021, a primary sclerosing cholangitis recurrence was diagnosed and a liver retransplantation was indicated. Recipient's hepatectomy was very difficult by reason of complex portal vein thrombosis requiring extensive thromboendovenectomy. Intraoperative ultrasound with liver doppler evaluation was performed. Two suspicious nodules were incidentally diagnosed in the donor's liver and immediately removed for anatomopathological evaluation. RESULTS: After pathological confirmation of carcinoma, probable cholangiocarcinoma, at frozen section, the patient was re-listed as national priority and a new liver transplantation was performed within 24 hours. The patient was discharged after 2 weeks. CONCLUSIONS: The screening for neoplasms in donated organs should be part of our strict daily diagnostic arsenal. Moreover, we argue that, for the benefit of an adequate diagnosis and the feasibility of a safer procedure, the adoption of imaging tests routine for the liver donor is essential, allowing a reduction of the costs and some potential risks of liver transplant procedure.

RESUMO RACIONAL: O transplante de fígado representa a melhor modalidade terapêutica na doença hepática crônica terminal, hepatite aguda grave e casos selecionados de tumores hepáticos. OBJETIVOS: Descrever um retransplante duplo em paciente do sexo masculino, diagnosticado com doença de Crohn e complicado com colangite esclerosante primária, hipertensão portal grave e colangiocarcinoma diagnosticado no fígado transplantado. MÉTODOS: Paciente do sexo masculino, 48 anos, diagnosticado com doença de Crohn há 25 anos e complicado com colangite esclerosante primária e hipertensão portal grave. Foi submetido a um transplante de fígado em 2018 devido a cirrose biliar secundária. Em 2021, foi diagnosticada recidiva de colangite esclerosante primária e indicado retransplante hepático. A hepatectomia do receptor foi de alta complexidade devido à trombose complexa da veia porta, exigindo extensa tromboendovenectomia. Foi realizada ultrassonografia intraoperatória com doppler hepático. Dois nódulos suspeitos foram diagnosticados incidentalmente no fígado do doador e imediatamente removidos para avaliação anatomopatológica. RESULTADOS: Após confirmação patológica de carcinoma, provável colangiocarcinoma, pela congelação, o paciente foi relistado como prioridade nacional, e novo transplante hepático foi realizado em 24 horas. O paciente teve alta após 2 semanas. CONCLUSÕES: O rastreamento de neoplasias em órgãos doados deve fazer parte de nosso estrito arsenal diagnóstico diário. Além disso, defendemos que, em benefício de um diagnóstico correto e da viabilidade de um procedimento mais seguro, a adoção de uma rotina de exames de imagem é essencial em doadores hepáticos, permitindo a redução dos custos e alguns riscos potenciais do procedimento de transplante hepático.