Mínguez Beatriz, García-Pagán Juan Carlos, Bosch Jaume, Turnes Juan, Alonso Juli, Rovira Alex, Córdoba Juan
Servei de Medicina Interna-Hepatologia, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.
Hepatology. 2006 Apr;43(4):707-14. doi: 10.1002/hep.21126.
Hepatic encephalopathy can arise from portal-systemic shunting in the absence of intrinsic liver disease. However, there are few descriptions of this form of encephalopathy. Portal vein thrombosis is an infrequent disease that causes portal-systemic shunting. Episodic hepatic encephalopathy has been described in patients with portal vein thrombosis, but it is not known if these patients develop minimal hepatic encephalopathy. We designed a study to investigate the neurological consequences of portal vein thrombosis in patients without cirrhosis and no clinical signs of encephalopathy. For this purpose, 10 patients underwent neuropsychological tests, an oral glutamine challenge test, and brain magnetic resonance (MR) imaging. The results were compared with those obtained in 10 healthy controls. Patients with portal vein thrombosis exhibited abnormalities in the results of neuropsychological tests, oral glutamine challenge test, and MR similar to those described in hepatic encephalopathy associated with cirrhosis. MR spectroscopy revealed a decrease in myo-inositol and an increase in glutamine. The increase in glutamine correlated with an increase in ammonia following the oral glutamine challenge test, signs of increased brain water (decrease in magnetization transfer ratio), and impairment of attention tests. In conclusion, patients with noncirrhotic portal vein thrombosis develop subclinical neurological abnormalities compatible with minimal hepatic encephalopathy. These disturbances, which include signs of increase in brain water and a compensatory osmotic response (decrease in brain myo-inositol), appear to be secondary to brain exposure to ammonia induced by portal-systemic shunting.
肝性脑病可在无内在肝脏疾病的情况下因门体分流而发生。然而，对这种形式的脑病描述较少。门静脉血栓形成是一种导致门体分流的罕见疾病。已有门静脉血栓形成患者出现发作性肝性脑病的报道，但尚不清楚这些患者是否会发展为轻微肝性脑病。我们设计了一项研究，以调查无肝硬化且无脑病临床体征的患者门静脉血栓形成的神经学后果。为此，10名患者接受了神经心理学测试、口服谷氨酰胺激发试验和脑磁共振成像。将结果与10名健康对照者的结果进行比较。门静脉血栓形成患者在神经心理学测试、口服谷氨酰胺激发试验和磁共振成像结果中表现出与肝硬化相关肝性脑病中描述的异常相似。磁共振波谱显示肌醇减少，谷氨酰胺增加。口服谷氨酰胺激发试验后谷氨酰胺的增加与氨的增加、脑含水量增加的迹象（磁化传递率降低）以及注意力测试受损相关。总之，非肝硬化门静脉血栓形成患者会出现与轻微肝性脑病相符的亚临床神经学异常。这些紊乱，包括脑含水量增加的迹象和代偿性渗透反应（脑肌醇减少），似乎继发于脑暴露于门体分流诱导的氨。
