RESUMO
Preventing SARS-CoV-2 infection by modulating viral host receptors, such as angiotensin-converting enzyme 2 (ACE2)1, could represent a new chemoprophylactic approach for COVID-19 that complements vaccination2,3. However, the mechanisms that control the expression of ACE2 remain unclear. Here we show that the farnesoid X receptor (FXR) is a direct regulator of ACE2 transcription in several tissues affected by COVID-19, including the gastrointestinal and respiratory systems. We then use the over-the-counter compound z-guggulsterone and the off-patent drug ursodeoxycholic acid (UDCA) to reduce FXR signalling and downregulate ACE2 in human lung, cholangiocyte and intestinal organoids and in the corresponding tissues in mice and hamsters. We show that the UDCA-mediated downregulation of ACE2 reduces susceptibility to SARS-CoV-2 infection in vitro, in vivo and in human lungs and livers perfused ex situ. Furthermore, we reveal that UDCA reduces the expression of ACE2 in the nasal epithelium in humans. Finally, we identify a correlation between UDCA treatment and positive clinical outcomes after SARS-CoV-2 infection using retrospective registry data, and confirm these findings in an independent validation cohort of recipients of liver transplants. In conclusion, we show that FXR has a role in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the way for future clinical trials.
Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Receptores Virais , Ácido Ursodesoxicólico , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/prevenção & controle , Receptores Virais/genética , Receptores Virais/metabolismo , Estudos Retrospectivos , SARS-CoV-2/metabolismo , Tratamento Farmacológico da COVID-19 , Cricetinae , Transcrição Gênica , Ácido Ursodesoxicólico/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Organoides/efeitos dos fármacos , Organoides/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , Sistema de Registros , Reprodutibilidade dos Testes , Transplante de FígadoRESUMO
Liver transplantation is a highly successful treatment, but is severely limited by the shortage in donor organs. However, many potential donor organs cannot be used; this is because sub-optimal livers do not tolerate conventional cold storage and there is no reliable way to assess organ viability preoperatively. Normothermic machine perfusion maintains the liver in a physiological state, avoids cooling and allows recovery and functional testing. Here we show that, in a randomized trial with 220 liver transplantations, compared to conventional static cold storage, normothermic preservation is associated with a 50% lower level of graft injury, measured by hepatocellular enzyme release, despite a 50% lower rate of organ discard and a 54% longer mean preservation time. There was no significant difference in bile duct complications, graft survival or survival of the patient. If translated to clinical practice, these results would have a major impact on liver transplant outcomes and waiting list mortality.
Assuntos
Aloenxertos/fisiologia , Transplante de Fígado/métodos , Fígado/fisiologia , Preservação de Órgãos/métodos , Temperatura , Coleta de Tecidos e Órgãos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aloenxertos/patologia , Aloenxertos/fisiopatologia , Aloenxertos/normas , Ductos Biliares/patologia , Ductos Biliares/fisiologia , Ductos Biliares/fisiopatologia , Feminino , Sobrevivência de Enxerto , Humanos , Tempo de Internação , Fígado/enzimologia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos/efeitos adversos , Perfusão , Análise de Sobrevida , Doadores de Tecidos/provisão & distribuição , Coleta de Tecidos e Órgãos/efeitos adversos , Resultado do Tratamento , Listas de Espera , Adulto JovemRESUMO
OBJECTIVE: To compare the outcomes of livers donated after circulatory death (DCD) and undergoing either in situ normothermic regional perfusion (NRP) or ex situ normothermic machine perfusion (NMP) with livers undergoing static cold storage (SCS). SUMMARY OF BACKGROUND DATA: DCD livers are associated with increased risk of primary nonfunction, poor function, and nonanastomotic strictures (NAS), leading to underutilization. METHODS: A single center, retrospective analysis of prospectively collected data on 233 DCD liver transplants performed using SCS, NRP, or NMP between January 2013 and October 2020. RESULTS: Ninety-seven SCS, 69 NRP, and 67 NMP DCD liver transplants were performed, with 6-month and 3-year transplant survival (graft survival non-censored for death) rates of 87%, 94%, 90%, and 76%, 90%, and 76%, respectively. NRP livers had a lower 6-month risk-adjusted Cox proportional hazard for transplant failure compared to SCS (hazard ratio 0.30, 95% Confidence Interval 0.08-1.05, P = 0.06). NRP and NMP livers had a risk-adjusted estimated reduction in the mean model for early allograft function score of 1.52 (P < 0.0001) and 1.19 (P < 0.001) respectively compared to SCS. Acute kidney injury was more common with SCS (55% vs 39% NRP vs 40% NMP; P = 0.08), with a lower risk-adjusted peak-to-baseline creatinine ratio in the NRP (P = 0.02). No NRP liver had clinically significant NAS in contrast to SCS (14%) and NMP (11%, P = 0.009), with lower risk-adjusted odds of overall NAS development compared to SCS (odds ratio = 0.2, 95%CI 0.06-0.72, P = 0.01). CONCLUSION: NRP and NMP were associated with better early liver function compared to SCS, whereas NRP was associated with superior preservation of the biliary system.
Assuntos
Transplante de Fígado , Sobrevivência de Enxerto , Humanos , Fígado , Transplante de Fígado/efeitos adversos , Preservação de Órgãos , Perfusão , Estudos Retrospectivos , Doadores de TecidosRESUMO
Cholangiocytes secrete bicarbonate and absorb glucose, producing bile with alkaline pH and low glucose content. These functions of cholangiocytes have been suggested as a marker of bile duct viability during normothermic ex situ liver perfusion, and they are now monitored routinely after reperfusion in our center. In this study, we reviewed the composition of bile immediately after reperfusion in liver transplant recipients to determine normal posttransplant parameters and the predictive value of bile biochemistry for the later development of cholangiopathy. After reperfusion of the liver graft, a cannula was placed in the bile duct to collect bile over a median 44-minute time period. The bile produced was analyzed using a point-of-care blood gas analyzer (Cobas b221, Roche Diagnostics, Indianapolis, IN). A total of 100 liver transplants (35 from donation after circulatory death and 65 from donation after brain death) were studied. Median bile pH was 7.82 (interquartile range [IQR], 7.67-7.98); median bile glucose was 2.1 (1.4-3.7) mmol/L; median blood-bile-blood pH difference was 0.50 (0.37-0.62); and median blood-bile glucose difference was 7.1 (5.6-9.1) mmol/L. There were 12 recipients who developed cholangiopathy over a median follow-up of 15 months (IQR, 11-20 months). Bile sodium (142 versus 147 mmol/L; P = 0.02) and blood-bile glucose concentration differences (5.2 versus 7.6 mmol/L; P = 0.001) were significantly lower and were associated with ischemic cholangiopathy. In conclusion, bile biochemistry may provide useful insights into cholangiocyte function and, hence, bile duct viability. Our results suggest bile glucose is the most sensitive predictor of cholangiopathy.
Assuntos
Bile , Transplante de Fígado , Ductos Biliares , Humanos , Fígado , Transplante de Fígado/efeitos adversos , Perfusão , ReperfusãoRESUMO
BACKGROUND: Pancreatic adenosquamous carcinoma has a poor prognosis, with limited prospective trial data to guide optimal treatment. The potential impact of drug metabolism on the treatment response of patients with pancreatic adenosquamous carcinoma is largely unknown. CASE PRESENTATION: We describe the case of a 51 year old woman with pancreatic adenosquamous carcinoma who, following surgical resection, experienced early disease relapse during adjuvant gemcitabine therapy. Paradoxically, this was followed by an exceptional response to capecitabine therapy lasting 34.6 months. Strong expression of cytidine deaminase was detected within the tumour. CONCLUSIONS: This case study demonstrates that early relapse during adjuvant chemotherapy for pancreatic adenosquamous carcinoma may be compatible with a subsequent exceptional response to second line chemotherapy, an important observation given the poor overall prognosis of patients with adenosquamous carcinoma. Cytidine deaminase is predicted to inactivate gemcitabine and, conversely, catalyze capecitabine activation. We discuss strong intra-tumoural expression of cytidine deaminase as a potential mechanism to explain this patient's disparate responses to gemcitabine and capecitabine therapy, and highlight the benefit that may be gained from considering similar determinants of response to chemotherapy in clinical practice.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma Adenoescamoso/tratamento farmacológico , Carcinoma Adenoescamoso/genética , Citidina Desaminase/genética , Desoxicitidina/análogos & derivados , Expressão Gênica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Carcinoma Adenoescamoso/diagnóstico , Quimioterapia Adjuvante , Citidina Desaminase/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Feminino , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidade , Recidiva , Retratamento , Tomografia Computadorizada por Raios X , Resultado do Tratamento , GencitabinaRESUMO
Livers from controlled donation after circulatory death (DCD) donors suffer a higher incidence of nonfunction, poor function, and ischemic cholangiopathy. In situ normothermic regional perfusion (NRP) restores a blood supply to the abdominal organs after death using an extracorporeal circulation for a limited period before organ recovery. We undertook a retrospective analysis to evaluate whether NRP was associated with improved outcomes of livers from DCD donors. NRP was performed on 70 DCD donors from whom 43 livers were transplanted. These were compared with 187 non-NRP DCD donor livers transplanted at the same two UK centers in the same period. The use of NRP was associated with a reduction in early allograft dysfunction (12% for NRP vs. 32% for non-NRP livers, P = .0076), 30-day graft loss (2% NRP livers vs. 12% non-NRP livers, P = .0559), freedom from ischemic cholangiopathy (0% vs. 27% for non-NRP livers, P < .0001), and fewer anastomotic strictures (7% vs. 27% non-NRP, P = .0041). After adjusting for other factors in a multivariable analysis, NRP remained significantly associated with freedom from ischemic cholangiopathy (P < .0001). These data suggest that NRP during organ recovery from DCD donors leads to superior liver outcomes compared to conventional organ recovery.
Assuntos
Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Adolescente , Adulto , Idoso , Doenças dos Ductos Biliares/prevenção & controle , Ductos Biliares/irrigação sanguínea , Criança , Morte , Função Retardada do Enxerto/prevenção & controle , Circulação Extracorpórea , Feminino , Sobrevivência de Enxerto , Humanos , Isquemia/prevenção & controle , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos/efeitos adversos , Perfusão/métodos , Estudos Retrospectivos , Temperatura , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/métodos , Adulto JovemRESUMO
Normothermic ex situ liver perfusion might allow viability assessment of livers before transplantation. Perfusion characteristics were studied in 47 liver perfusions, of which 22 resulted in transplants. Hepatocellular damage was reflected in the perfusate transaminase concentrations, which correlated with posttransplant peak transaminase levels. Lactate clearance occurred within 3 hours in 46 of 47 perfusions, and glucose rose initially during perfusion in 44. Three livers required higher levels of bicarbonate support to maintain physiological pH, including one developing primary nonfunction. Bile production did not correlate with viability or cholangiopathy, but bile pH, measured in 16 of the 22 transplanted livers, identified three livers that developed cholangiopathy (peak pH < 7.4) from those that did not (pH > 7.5). In the 11 research livers where it could be studied, bile pH > 7.5 discriminated between the 6 livers exhibiting >50% circumferential stromal necrosis of septal bile ducts and 4 without necrosis; one liver with 25-50% necrosis had a maximum pH 7.46. Liver viability during normothermic perfusion can be assessed using a combination of transaminase release, glucose metabolism, lactate clearance, and maintenance of acid-base balance. Evaluation of bile pH may offer a valuable insight into bile duct integrity and risk of posttransplant ischemic cholangiopathy.
Assuntos
Ductos Biliares/metabolismo , Hepatócitos/metabolismo , Transplante de Fígado , Preservação de Órgãos/métodos , Perfusão/métodos , Disfunção Primária do Enxerto/prevenção & controle , Doadores de Tecidos/provisão & distribuição , Adulto , Biomarcadores/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Traumatismo por Reperfusão/prevenção & controle , Obtenção de Tecidos e Órgãos/normas , Adulto JovemRESUMO
CONTEXT: Development of mediastinal pancreatic pseudocysts is a rare complication of pancreatitis. There is currently no consensus on the optimal management of this condition, options for which include conservative management with somatostatin analogues, endoscopic drainage procedures and surgery. CASE REPORT: Here we present two patients with mediastinal pancreatic pseudocysts which were initially managed endoscopically. However, in both cases, this led to complications secondary to the endoscopic procedures, recurrence or non-resolution of symptoms, requiring surgical cystogastrostomy and/or cystojejunostomy. CONCLUSION: These cases suggest that surgery may be ultimately necessary for mediastinal pancreatic pseudocysts where endoscopic procedures might have a high likelihood of failure.
RESUMO
Background: Desmoid tumors are fibroblastic lesions which often have an unpredictable and variable clinical course. In the context of familial adenomatous polyposis (FAP), these frequently occur intra-abdominally, especially in the small-bowel mesentery resulting in sepsis, fistulation, and invasion of the abdominal wall and retroperitoneum. In selected cases where other modalities have failed, the most radical option is to perform a total enterectomy and intestinal transplantation (ITx). In this study, we present our center's experience of ITx for desmoid in patients with FAP. Methods: We performed a retrospective review of our prospectively collected database between 2007 and 2022. All patients undergoing ITx for FAP-related desmoid were included. Results: Between October 2007 and September 2023, 144 ITx were performed on 130 patients at our center. Of these, 15 patients (9%) were for desmoid associated with FAP (7 modified multivisceral transplants, 6 isolated ITx, and 2 liver-containing grafts). The median follow-up was 57 mo (8-119); 5-y patient survival was 82%, all with functioning grafts without local desmoid recurrence. These patients presented us with several complex surgical issues, such as loss of abdominal domain, retroperitoneal/abdominal wall involvement, ileoanal pouch-related issues, and the need for foregut resection because of adenomatous disease. Conclusions: ITx is a viable treatment in selected patients with FAP and extensive desmoid disease. The decision to refer for ITx can be challenging, particularly the timing and sequence of treatment (simultaneous versus sequential exenteration). Delays can result in additional disease burden, such as secondary liver disease or invasion of adjacent structures.
RESUMO
BACKGROUND: Bile chemistry during normothermic ex situ liver perfusion (NESLiP) has been suggested to be an indicator of cholangiopathy. The normal range of biochemical variables in bile of livers undergoing NESLiP has not been defined, nor have published biliary viability criteria been assessed against instances of posttransplant nonanastomotic bile strictures (NASs). METHODS: The bile and perfusate chemistry of 200 livers undergoing NESLiP between February 1, 2018, and October 30, 2023, was compared. In addition, 11 livers that underwent NESLiP and later developed NAS were selected and their bile chemistry was also examined. RESULTS: In livers that did not develop cholangiopathy, concentrations of sodium, potassium, and chloride were slightly higher in bile than in perfusate, whereas the concentration of calcium was slightly lower. Bile was alkali and had a lower glucose concentration than perfusate. Cholangiocyte glucose reabsorption was shown to saturate at high perfusate concentrations and was more impaired in livers donated after circulatory death than in livers donated after brain death. Published criteria failed to identify all livers that went on to develop NASs. CONCLUSIONS: A significant false-negative rate exists with current biliary viability criteria, probably reflecting the patchy and incomplete nature of the development of NASs in the biliary tree. The data presented here provide a benchmark for future assessment of bile duct chemistry during NESLiP.
Assuntos
Bile , Transplante de Fígado , Fígado , Preservação de Órgãos , Perfusão , Humanos , Transplante de Fígado/efeitos adversos , Bile/metabolismo , Bile/química , Preservação de Órgãos/métodos , Fígado/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Colestase , Adulto , Estudos Retrospectivos , Constrição PatológicaRESUMO
BACKGROUND: Normothermic ex situ liver perfusion (NESLiP) has the potential to increase organ utilization. Radiological evidence of localized liver injury due to compression at the time of NESLiP, termed cradle compression, is a recognized phenomenon but is poorly characterized. METHODS: A retrospective analysis of a prospectively collected database was performed of transplanted livers that underwent NESLiP and subsequently had a computed tomography performed within the first 14 d posttransplant. The primary study outcome was 1-y graft survival. RESULTS: Seventy livers (63%) were included in the analysis. Radiological evidence of cradle compression was observed in 21 of 70 (30%). There was no difference in rate of cradle compression between donor after circulatory death and donated after brain death donors ( P â =â 0.37) or with duration of NESLiP. Univariate analysis demonstrated younger (area under the receiver operating characteristic, 0.68; P = 0.008; 95% confidence interval [CI], 0.55-0.82) and heavier (area under the receiver operating characteristic, 0.80; P â <â 0.001; 95% CI, 0.69-0.91) livers to be at risk of cradle compression. Only liver weight was associated with cradle compression on multivariate analysis (odds ratio, 1.003; P â =â 0.005; 95% CI, 1.001-1.005). There was no difference in 1-y graft survival (16/17 [94.1%] versus 44/48 [91.6%]; odds ratio, 0.69; P â =â 0.75; 95% CI, 0.07-6.62). CONCLUSIONS: This is the first study assessing the impact of cradle compression on outcome. We have identified increased donor liver weight and younger age as risk factors for the development of this phenomenon. Increasing utilization of NESLiP will result in the increased incidence of cradle compression but the apparent absence of long-term sequelae is reassuring. Routine postoperative axial imaging may be warranted.
Assuntos
Sobrevivência de Enxerto , Transplante de Fígado , Fígado , Perfusão , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Masculino , Perfusão/métodos , Perfusão/efeitos adversos , Feminino , Pessoa de Meia-Idade , Fígado/diagnóstico por imagem , Fígado/irrigação sanguínea , Fígado/patologia , Adulto , Resultado do Tratamento , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Preservação de Órgãos/métodos , Preservação de Órgãos/efeitos adversos , Análise Multivariada , Idoso , Doadores de Tecidos , Tamanho do ÓrgãoRESUMO
BACKGROUND: Management strategies and clinical outcomes vary substantially in patients newly diagnosed with Crohn's disease. We evaluated the use of a putative prognostic biomarker to guide therapy by assessing outcomes in patients randomised to either top-down (ie, early combined immunosuppression with infliximab and immunomodulator) or accelerated step-up (conventional) treatment strategies. METHODS: PROFILE (PRedicting Outcomes For Crohn's disease using a moLecular biomarker) was a multicentre, open-label, biomarker-stratified, randomised controlled trial that enrolled adults with newly diagnosed active Crohn's disease (Harvey-Bradshaw Index ≥7, either elevated C-reactive protein or faecal calprotectin or both, and endoscopic evidence of active inflammation). Potential participants had blood drawn to be tested for a prognostic biomarker derived from T-cell transcriptional signatures (PredictSURE-IBD assay). Following testing, patients were randomly assigned, via a secure online platform, to top-down or accelerated step-up treatment stratified by biomarker subgroup (IBDhi or IBDlo), endoscopic inflammation (mild, moderate, or severe), and extent (colonic or other). Blinding to biomarker status was maintained throughout the trial. The primary endpoint was sustained steroid-free and surgery-free remission to week 48. Remission was defined by a composite of symptoms and inflammatory markers at all visits. Flare required active symptoms (HBI ≥5) plus raised inflammatory markers (CRP >upper limit of normal or faecal calprotectin ≥200 µg/g, or both), while remission was the converse-ie, quiescent symptoms (HBI <5) or resolved inflammatory markers (both CRP ≤ the upper limit of normal and calprotectin <200 µg/g) or both. Analyses were done in the full analysis (intention-to-treat) population. The trial has completed and is registered (ISRCTN11808228). FINDINGS: Between Dec 29, 2017, and Jan 5, 2022, 386 patients (mean age 33·6 years [SD 13·2]; 179 [46%] female, 207 [54%] male) were randomised: 193 to the top-down group and 193 to the accelerated step-up group. Median time from diagnosis to trial enrolment was 12 days (range 0-191). Primary outcome data were available for 379 participants (189 in the top-down group; 190 in the accelerated step-up group). There was no biomarker-treatment interaction effect (absolute difference 1 percentage points, 95% CI -15 to 15; p=0·944). Sustained steroid-free and surgery-free remission was significantly more frequent in the top-down group than in the accelerated step-up group (149 [79%] of 189 patients vs 29 [15%] of 190 patients, absolute difference 64 percentage points, 95% CI 57 to 72; p<0·0001). There were fewer adverse events (including disease flares) and serious adverse events in the top-down group than in the accelerated step-up group (adverse events: 168 vs 315; serious adverse events: 15 vs 42), with fewer complications requiring abdominal surgery (one vs ten) and no difference in serious infections (three vs eight). INTERPRETATION: Top-down treatment with combination infliximab plus immunomodulator achieved substantially better outcomes at 1 year than accelerated step-up treatment. The biomarker did not show clinical utility. Top-down treatment should be considered standard of care for patients with newly diagnosed active Crohn's disease. FUNDING: Wellcome and PredictImmune Ltd.
Assuntos
Doença de Crohn , Adulto , Humanos , Masculino , Feminino , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/complicações , Infliximab/uso terapêutico , Azatioprina/uso terapêutico , Biomarcadores , Fatores Imunológicos/uso terapêutico , Inflamação , Complexo Antígeno L1 LeucocitárioRESUMO
Clinicians working in any acute medical/surgical unit need an understanding of mesenteric ischaemia. Acute mesenteric ischaemia is a life-threatening vascular emergency associated with high morbidity and mortality. However, prompt diagnosis with the use of contrast-enhanced CT, more specifically CT angiography, has replaced catheter angiography as the new standard and is readily available in many emergency departments. Similarly, new hybrid open surgery endovascular treatment can minimise the surgical insult to these often critically ill elderly patients. Together, these changes can change the previously grim prognosis associated with this condition. By contrast, chronic mesenteric ischaemia (CMI) is an insidious disease and often a diagnosis of exclusion. However, it can cause a significant reduction in a patient's quality of life, due to 'mesenteric angina' and food avoidance, yet can potentially be treated simply and effectively. Recognition of the typical clinical history and imaging findings is key to making the diagnosis in a timely fashion. Radiology plays a significant role in the diagnosis and increasingly in the treatment of mesenteric ischaemia. Other clinicians should have a basic understanding of what radiology can and cannot offer. The advantages and limitations of commonly used imaging modalities-plain films, CT, MRI and ultrasound, are examined. The significance of findings, such as pneumatosis coli and portal gas are explained. Finally, the different endovascular management of both acute and CMI is discussed, which have emerged as minimally invasive options to complement open revascularisation surgery.
Assuntos
Isquemia/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Doenças Vasculares/diagnóstico , Angiografia/métodos , Diagnóstico por Imagem/métodos , Humanos , Isquemia/diagnóstico por imagem , Isquemia/terapia , Isquemia Mesentérica , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/terapiaRESUMO
BACKGROUND: Deceased donor livers are prone to biliary complications, which may necessitate retransplantation, and we, and others, have suggested that these complications are because of peribiliary vascular fibrin microthrombi. We sought to determine the prevalence and consequence of occult fibrin within deceased donor livers undergoing normothermic ex situ perfusion (NESLiP) and evaluate a role for fibrinolysis. METHODS: D-dimer concentrations, products of fibrin degradation, were assayed in the perfusate of 163 livers taken after 2 h of NESLiP, including 91 that were transplanted. These were related to posttransplant outcomes. Five different fibrinolytic protocols during NESLiP using alteplase were evaluated, and the transplant outcomes of these alteplase-treated livers were reviewed. RESULTS: Perfusate D-dimer concentrations were lowest in livers recovered using in situ normothermic regional perfusion and highest in alteplase-treated livers. D-dimer release from donation after brain death livers was significantly correlated with the duration of cold ischemia. In non-alteplase-treated livers, Cox proportional hazards regression analysis showed that D-dimer levels were associated with transplant survival ( P = 0.005). Treatment with alteplase and fresh frozen plasma during NESLiP was associated with significantly more D-dimer release into the perfusate and was not associated with excess bleeding postimplantation; 8 of the 9 treated livers were free of cholangiopathy, whereas the ninth had a proximal duct stricture. CONCLUSIONS: Fibrin is present in many livers during cold storage and is associated with poor posttransplant outcomes. The amount of D-dimer released after fibrinolytic treatment indicates a significant occult fibrin burden and suggests that fibrinolytic therapy during NESLiP may be a promising therapeutic intervention.
Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Fibrina/metabolismo , Preservação de Órgãos/métodos , Fígado/irrigação sanguínea , Perfusão/métodosRESUMO
BACKGROUND: Normothermic ex situ liver perfusion is increasingly used to assess donor livers, but there remains a paucity of evidence regarding criteria upon which to base a viability assessment or criteria predicting early allograft function. METHODS: Perfusate variables from livers undergoing normothermic ex situ liver perfusion were analyzed to see which best predicted the Model for Early Allograft Function score. RESULTS: One hundred fifty-four of 203 perfused livers were transplanted following our previously defined criteria. These comprised 84/123 donation after circulatory death livers and 70/80 donation after brain death livers. Multivariable analysis suggested that 2-h alanine transaminase, 2-h lactate, 11 to 29 mmol supplementary bicarbonate in the first 4 h, and peak bile pH were associated with early allograft function as defined by the Model for Early Allograft Function score. Nonanastomotic biliary strictures occurred in 11% of transplants, predominantly affected first- and second-order ducts, despite selection based on bile glucose and pH. CONCLUSIONS: This work confirms the importance of perfusate alanine transaminase and lactate at 2-h, as well as the amount of supplementary bicarbonate required to keep the perfusate pH > 7.2, in the assessment of livers undergoing perfusion. It cautions against the use of lactate as a sole indicator of viability and also suggests a role for cholangiocyte function markers in predicting early allograft function.
Assuntos
Bicarbonatos , Transplante de Fígado , Alanina Transaminase , Transplante de Fígado/efeitos adversos , Perfusão/efeitos adversos , Fígado , Lactatos , Aloenxertos , Preservação de ÓrgãosRESUMO
Organoid technology holds great promise for regenerative medicine but has not yet been applied to humans. We address this challenge using cholangiocyte organoids in the context of cholangiopathies, which represent a key reason for liver transplantation. Using single-cell RNA sequencing, we show that primary human cholangiocytes display transcriptional diversity that is lost in organoid culture. However, cholangiocyte organoids remain plastic and resume their in vivo signatures when transplanted back in the biliary tree. We then utilize a model of cell engraftment in human livers undergoing ex vivo normothermic perfusion to demonstrate that this property allows extrahepatic organoids to repair human intrahepatic ducts after transplantation. Our results provide proof of principle that cholangiocyte organoids can be used to repair human biliary epithelium.
Assuntos
Doenças dos Ductos Biliares/terapia , Ductos Biliares Intra-Hepáticos/fisiologia , Ductos Biliares/citologia , Terapia Baseada em Transplante de Células e Tecidos , Células Epiteliais/citologia , Organoides/transplante , Animais , Bile , Ductos Biliares/fisiologia , Ductos Biliares Intra-Hepáticos/citologia , Ducto Colédoco/citologia , Células Epiteliais/fisiologia , Vesícula Biliar/citologia , Regulação da Expressão Gênica , Humanos , Fígado/fisiologia , Transplante de Fígado , Transplante de Células-Tronco Mesenquimais , Camundongos , Organoides/fisiologia , RNA-Seq , Obtenção de Tecidos e Órgãos , TranscriptomaRESUMO
Introduction: Antifungal agents are routinely used in the post-transplant setting for both prophylaxis and treatment of presumed and proven fungal infections. Micafungin is an echinocandin-class antifungal with broad antifungal cover and favorable side effect profile but, notably, it has no activity against molds of the order Mucorales. Presentation of case: A 47-year-old woman underwent multivisceral transplantation for intestinal failure-associated liver disease. She had a prolonged post-operative recovery complicated by invasive candidiasis and developed an intolerance to liposomal amphotericin B. In view of her immunosuppression, she was commenced on micafungin as prophylaxis to prevent invasive fungal infection. However, she developed acute graft versus host disease with bone marrow failure complicated by disseminated mucormycosis which was only diagnosed post mortem. Discussion: Non-Aspergillus breakthrough mold infections with micafungin therapy are rare with only eight other cases having been described in the literature. Breakthrough infections have occurred within one week of starting micafungin. Diagnosis is problematic and requires a high degree of clinical suspicion and microscopic/histological examination of an involved site. The management of these aggressive infections involves extensive debridement and appropriate antifungal cover. Conclusion: A high level of suspicion of invasive fungal infection is required at all times in immunosuppressed patients, even those receiving antifungal prophylaxis. Early biopsy is required. Even with early recognition and aggressive treatment of these infections, prognosis is poor.
RESUMO
BACKGROUND: The course of Crohn's disease (CD) varies substantially between individuals, but reliable prognostic markers do not exist. This hinders disease management because patients with aggressive disease are undertreated by conventional 'step-up' therapy (in which treatment is gradually escalated in response to refractory or relapsing disease) while those with more indolent disease would be exposed to unnecessary treatment-related toxicity if a more aggressive 'top-down' approach was indiscriminately used. The Predicting outcomes for Crohn's disease using a molecular biomarker trial will assess whether a prognostic transcriptional biomarker, that we have developed and validated, can improve clinical outcomes by facilitating personalised therapy in CD. This represents the first the biomarker-stratified trial in inflammatory bowel disease. METHODS AND ANALYSIS: This biomarker-stratified trial will compare the relative efficacy of 'top-down' and 'accelerated step-up' therapy between biomarker-defined subgroups of patients with newly diagnosed CD. 400 participants from ~50 UK centres will be recruited. Subjects within each biomarker subgroup (IBDhi or IBDlo) will be randomised (1:1) to receive one of the treatment strategies until trial completion (48 weeks). The primary outcome is the incidence of sustained surgery and steroid-free remission from the completion of induction treatment through to week 48. Secondary outcomes include mucosal healing, quality-of-life assessments and surrogate measures of disease burden including number of flares, cumulative steroid exposure, number of hospital admissions and number of Crohn's-related surgeries (assessed hierarchically). Analyses will compare the relative benefit of the treatment strategies in each biomarker-defined subgroup, powered as an interaction analysis, to determine whether the biomarker can accurately match patients to the most appropriate therapy. ETHICS AND DISSEMINATION: Ethical approval has been obtained and recruitment is under way at sites around the UK. Following trial completion and data analysis, the results of the trial will be submitted for publication in peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBER: ISRCTN11808228; Pre-results.
Assuntos
Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Marcadores Genéticos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Anti-Inflamatórios/uso terapêutico , Humanos , Estudos Multicêntricos como Assunto , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Indução de RemissãoRESUMO
INTRODUCTION: Hepatic morphology changes are well described in Primary Sclerosing Cholangitis and characterised by a combination of atrophy and hypertrophy changes. This study investigates the relationship between progression of these changes over time and clinical outcome in patients with PSC. METHODS: Fifty-three patients with PSC (mean age 44, 28 males and 25 females) who underwent serial MRI liver studies at least one year apart were identified. The first and the last MRI studies were selected for the retrospective analysis. Three radiologists reviewed and compared both studies for changes in hepatic morphology, specifically atrophy and/or hypertrophy. The imaging findings were correlated with adverse clinical outcomes defined as death or liver transplantation and with serum bilirubin. RESULTS: There was a mean interval of 60 months between MRI examinations and a mean clinical follow-up period thereafter of 22 months. Thirty-three (62.3%) patients had stable hepatic morphology, whilst 20 (37.7%) patients showed hepatic morphology changes (atrophy: 13 patients, 24%; hypertrophy: 16 patients, 30%). Eleven patients (21%) died or underwent liver transplantation. There was a significant correlation between interval hepatic atrophy and adverse clinical outcomes (P = 0.001). Significant correlations were found between increasing serum bilirubin level and interval hepatic atrophy, hepatic hypertrophy and combined changes (P = 0.025, P = 0.022, P = 0.027, respectively). CONCLUSION: Hepatic morphology changes over time in patients with PSC are heterogeneous with some patients developing atrophy and/or hypertrophy whilst other patients remain stable. In this retrospective study, progressive hepatic atrophy showed significant association with adverse clinical outcome defined by either death or liver transplantation.