Graft Survival in Liver Transplantation: An Artificial Neuronal Network Assisted Analysis of the Importance of Comorbidities.

OBJECTIVES: Liver transplant represents a widespread therapeutic option for patients with end-stage liver failure. Up to now, most of the scores describing the probability of liver graft survival have shown poor predictive performance. With this in mind, the present study seeks to analyze the predictive value of recipient comorbidities on liver graft survival within the first year. MATERIALS AND METHODS: The study included prospectively collected data from patients who received a liver transplant at our center from 2010 to 2021. A predictive model was then developed through an Artificial Neural Network that included the parameters associated with graft loss as identified by the Spanish Liver Transplant Registry report and comorbidities with prevalence >2% present in our study cohort. RESULTS: Most patients in our study were men (75.5%); mean age was 54.8 ± 9.6 years. The main cause of transplant was cirrhosis (86.7%), and 67.4% of patients had some associated comorbidities. Graft loss due to retransplant or death with dysfunction occurred in 14% of cases. Of all the variables analyzed, we found 3 comorbidities associated with graft loss (as shown by informative value and normalized informative value, respectively): antiplatelet and/or anticoagulants treatments (0.124 and 78.4%), previous immunosuppression (0.110 and 69.6%), and portal thrombosis (0.105 and 66.3%). Remarkably, our model showed a C statistic of 0.745 (95% CI, 0.692-0.798; asymptotic P < .001), which was higher than others found in previous studies. CONCLUSIONS: Our model identified key parameters that may influence graft loss, including specific recipient comorbidities. The use of artificial intelligence methods could reveal connections that may be overlooked by conventional statistics.

Ischemic cholangiopathy following hepatic artery pseudoaneurysm with thrombosis.

We report the case of a 73-year-old male, with a history of liver cirrhosis secondary to hepatitis C virus (HCV). Due to this condition he underwent a liver transplant (LT) in 1993. From then on he was given immunosuppressive treatment with cyclosporin in monotherapy.

Hepatitis C: A Pharmacological Therapeutic Update.

(1) Background: Hepatitis C is a high-prevalence disease, representing a global impact health problem. Lately, many changes have been made in treatment guidelines because of the commercialization of second-generation direct-acting antivirals due to their high effectiveness, few side effects and pangenotypic action. We address the pharmacological possibilities available and compare them with the current recommendations of the World Health Organization (WHO). (2) Methods: The search for articles was made through the PubMed database using different search strategies and we consulted technical data sheets of the treatments that have been included in the study. (3) Results: Combinations of "glecaprevir/pibrentasvir", "sofosbuvir/velpatasvir" and "sofosbuvir/velpatasvir/voxilaprevir" have been recently incorporated. Phase II studies have shown that they are safe and effective therapies with very comfortable posologies and easy therapeutic adherence; furthermore, they suppose shorter treatment duration. Subsequently, phase III studies have shown they were effective for previously treated or compensated cirrhotic patients that previously had more complex treatment regimens. (4) Conclusions: These results suppose a simplification in Hepatitis C therapeutic approach, and open new study possibilities.

Supervivencia del injerto tras trasplante hepático: aproximación a un nuevo índice de riesgo español / Graft survival after liver transplantation: an approach to a new Spanish risk index

Introducción: existen diversos indicadores para la valoración de la supervivencia del injerto hepático (DRI americano y ET-DRI europeo, entre otros), pero existen diferencias importantes entre los programas de trasplante de los diferentes países y podría ser que dichos indicadores no sean válidos en nuestro medio. Objetivos: el objetivo de este estudio es describir un nuevo indicador nacional de riesgo del injerto hepático a partir de los resultados del Registro Español de Trasplante Hepático (RETH) y validar el DRI y el ET-DRI. Metodología: el RETH incluye un análisis de Cox de los factores relacionados con la supervivencia del injerto. En base a sus resultados se define el indicador graft risk index (GRI). Las variables que contempla dependen del proceso de donación: edad, causa de muerte, compatibilidad sanguínea y tiempo de isquemia fría; y del receptor: edad, enfermedad de base, virus C, número de trasplante, estado UNOS y técnica quirúrgica. Se obtuvo la curva de la regresión logística y se calcularon las curvas de supervivencia del injerto por estratificación. La precisión se evaluó mediante el área ROC. Resultados: un GRI de 1 se corresponde con una probabilidad de pérdida del injerto del 23,25%; cada punto de aumento del GRI supone que la probabilidad se multiplica por 1,33. El GRI mostró la mejor discriminación por estratificación. El área ROC del DRI fue 0,54 (95% IC, 0,50-0,59) y del ET-DRI, 0,56 (95% IC, 0,51-0,61), frente al GRI 0,70 (95% IC, 0,65-0,73) (p < 0,0001). Conclusiones: el DRI y el ET-DRI no parecen útiles en nuestro medio y sería necesario disponer de un indicador propio. El GRI requiere un estudio nacional que perfile más el indicador y realice una validación más amplia

Introduction: several indicators are available to assess liver graft survival, including the American DRI and the European ET-DRI. However, there are significant differences between transplant programs of different countries, and the previously mentioned indicators might be not valid in our setting. Objectives: the aim of the study was to describe a new national liver graft risk indicator based on the results obtained from the Registro Español de Trasplante Hepático (RETH) and to validate the DRI and ET-DRI indicators. Methods: the RETH includes a Cox analysis of factors associated with graft survival; the graft risk index (GRI) indicator was defined based on these results. The variables considered are dependent upon the donation conditions (age, cause of death, blood compatibility and cold ischemia time) and the transplant recipient (age, underlying disease, hepatitis C virus, transplant number, UNOS status and surgical technique). A logistic regression curve was obtained and graft survival curves were calculated by stratification. Precision was assessed using the ROC analysis. Results: a GRI of 1 represents a probability of graft loss of 23.25%; each point increase in the GRI score multiplies this probability by 1.33. The best discrimination of GRI was obtained by stratification. The DRI ROC area was 0.54 (95% CI, 0.50-0.59) and the ET-DRI ROC area was 0.56 (95% CI, 0.51-0.61), compared to 0.70 (95% CI, 0.65-0.73) (p < 0.0001) for the GRI. Conclusions: both the DRI and ET-DRI do not seem to be useful in our setting. Hence a national indicator is more desirable. The GRI requires a national study in order to further streamline and assess this indicator

Graft survival after liver transplantation: an approach to a new Spanish risk index.

INTRODUCTION: several indicators are available to assess liver graft survival, including the American DRI and the European ET-DRI. However, there are significant differences between transplant programs of different countries, and the previously mentioned indicators might be not valid in our setting. OBJECTIVES: the aim of the study was to describe a new national liver graft risk indicator based on the results obtained from the Registro Español de Trasplante Hepático (RETH) and to validate the DRI and ET-DRI indicators. METHODS: the RETH includes a Cox analysis of factors associated with graft survival; the graft risk index (GRI) indicator was defined based on these results. The variables considered are dependent upon the donation conditions (age, cause of death, blood compatibility and cold ischemia time) and the transplant recipient (age, underlying disease, hepatitis C virus, transplant number, UNOS status and surgical technique). A logistic regression curve was obtained and graft survival curves were calculated by stratification. Precision was assessed using the ROC analysis. RESULTS: a GRI of 1 represents a probability of graft loss of 23.25%; each point increase in the GRI score multiplies this probability by 1.33. The best discrimination of GRI was obtained by stratification. The DRI ROC area was 0.54 (95% CI, 0.50-0.59) and the ET-DRI ROC area was 0.56 (95% CI, 0.51-0.61), compared to 0.70 (95% CI, 0.65-0.73) (p < 0.0001) for the GRI. CONCLUSIONS: both the DRI and ET-DRI do not seem to be useful in our setting. Hence a national indicator is more desirable. The GRI requires a national study in order to further streamline and assess this indicator.

Inmunosupresión en el trasplante hepático: pautas renoprotectoras / Immunosuppression in Liver Transplantation: Renoprotective Regimens

Tanto la insuficiencia renal aguda como la crónica son altamente prevalentes en los pacientes con trasplante hepático. La etiología es multifactorial, desempeñando un papel muy importante la administración de fármacos nefrotóxicos. Los inhibidores de la calcineurina (ICN) (ciclosporina y tacrolimus) son el pilar básico del tratamiento inmunosupresor en el trasplante hepático y producen nefrotoxicidad aguda y crónica. Las pautas de prevención de daño renal incluyen tres estrategias fundamentales: a) reducción del ICN a niveles mínimos acompañada de la utilización de un fármaco adyuvante como la azatioprina, el micofenolato mofetilo o los inhibidores mTOR; b) retirada total de los ICN, utilizando en su lugar fármacos no nefrotóxicos; y por último c) utilización desde un principio de protocolos sin ICN. En este artículo se revisarán estas estrategias así como su influencia en la función renal y en los resultados del trasplante hepático (AU)

Both acute and chronic renal insufficiency are highly prevalent in liver transplant recipients. The etiology is multifactorial, with administration of nephrotoxic drugs playing a major role. Calcineurin inhibitors (CNI) (cyclosporin and tacrolimus) are the mainstay of immunosuppressive therapy in liver transplantation and produce acute and chronic nephrotoxicity. There are three main strategies to prevent renal injury: a) reduction of CNI to minimal levels accompanied by the use of an adjuvant drug such as azathioprine, mycophenolate mofetil or mammalian target of rapamycin (mTOR) inhibitors; b) complete withdrawal of CNI, using non-nephrotoxic drugs in their place; and c) use of protocols without CNI from the outset. The present article reviews these three strategies as well as their influence on renal function and on the results of liver transplantation (AU)

[Immunosuppression in liver transplantation: renoprotective regimens]. / Inmunosupresión en el trasplante hepático: pautas renoprotectoras.

Both acute and chronic renal insufficiency are highly prevalent in liver transplant recipients. The etiology is multifactorial, with administration of nephrotoxic drugs playing a major role. Calcineurin inhibitors (CNI) (cyclosporin and tacrolimus) are the mainstay of immunosuppressive therapy in liver transplantation and produce acute and chronic nephrotoxicity. There are three main strategies to prevent renal injury: a) reduction of CNI to minimal levels accompanied by the use of an adjuvant drug such as azathioprine, mycophenolate mofetil or mammalian target of rapamycin (mTOR) inhibitors; b) complete withdrawal of CNI, using non-nephrotoxic drugs in their place; and c) use of protocols without CNI from the outset. The present article reviews these three strategies as well as their influence on renal function and on the results of liver transplantation.