[A case of portal-systemic encephalopathy with slowly progressive, non-flapping tremor]

A 52-year-old man has slowly developed a non-flapping tremor during 30 years. He also had suffered from poor concentration for two years. He had, however, no history of episodic disturbance of consciousness. He had no other neurological symptoms except for tremor and hyperreflexia. The tremor was postural and intentional, and extremely increased at the end point. The factor of intentional tremor and hyperkinesia volitionnelle seems to be present in the tremor. Laboratory examination disclosed a hyperammonemia, reduction in Fisher ratio, and poor excretion of ICG. Selective abdominal angiography visualized a large shunt vessel between the left gastric vein and the left renal vein. The normal liver scintigram with 99mTc excluded the dysfunction of liver, and we conclude that the shunt vessel might be congenital. Tremor markedly improved after normalizing blood ammonia level by resection of the shunt vessel. The present case suggests that tremor, even without episodic disturbance of consciousness, could be based on the portal-systemic encephalopathy.