Córdoba Juan, Mínguez Beatriz
Servei de Medicina Interna-Hepatologia, Hospital Vall d'Hebron, Departament de Medicina, Universitat Autònoma de Barcelona, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Spain.
Semin Liver Dis. 2008 Feb;28(1):70-80. doi: 10.1055/s-2008-1040322.
Hepatic encephalopathy is a severe complication of cirrhosis that is related to the effects of ammonia. Analysis of interorgan ammonia trafficking has identified an important role of skeletal muscle in ammonia removal and has highlighted the importance of the nutritional status. Ammonia causes neurotransmitter abnormalities and induces injury to astrocytes that is partially mediated by oxidative stress. These disturbances lead to astrocyte swelling and brain edema, which appear to be involved in the pathogenesis of neurological manifestations. Inflammatory mediators worsen brain disturbances. New methods for assessing hepatic encephalopathy include clinical scales, neuropsychological tests, imaging of portal-systemic circulation, and magnetic resonance of the brain. Reappraisal of current therapy indicates the need for performing placebo-controlled trials and the lack of evidence for administering diets with restricted protein content. Liver transplant should be considered in selected patients with hepatic encephalopathy. Future prospects include new drugs that decrease plasma ammonia, measures to reduce brain edema, and liver-support devices.
肝性脑病是肝硬化的一种严重并发症，与氨的作用有关。对器官间氨转运的分析已确定骨骼肌在氨清除中起重要作用，并突出了营养状况的重要性。氨会导致神经递质异常，并诱导星形胶质细胞损伤，这部分是由氧化应激介导的。这些紊乱会导致星形胶质细胞肿胀和脑水肿，这似乎与神经症状的发病机制有关。炎症介质会加重脑部紊乱。评估肝性脑病的新方法包括临床量表、神经心理学测试、门体循环成像和脑部磁共振成像。对当前治疗方法的重新评估表明，需要进行安慰剂对照试验，而且缺乏给予低蛋白饮食的证据。对于选定的肝性脑病患者应考虑进行肝移植。未来的前景包括降低血浆氨的新药、减轻脑水肿的措施以及肝脏支持装置。
