[A case of adult-onset type II citrullinemia (CTLN2) triggered by an overseas travel].

A 43-year-old male presented with abnormal behavior and consciousness disturbance on the day after traveling abroad and was admitted to our hospital. Laboratory tests showed hyperammonemia and hypercitrullinemia. The electro-encephalogram showed frontal dominant bilateral slow δ burst. He had a peculiar taste for nuts. But he didn't take nuts during the overseas travel for 3 days. The family history revealed that his younger brother died of a status epilepticus of unknown cause at the age of 29. These findings were compatible with hepatic encephalopathy due to adult-onset type II citrullinemia (CTLN2). Gene analysis provided a definite diagnosis of CTLN2. Diet and drug therapy have improved his condition. He is due to have liver transplantation which is the only established radical treatment for CTLN2 if his condition becomes worse. The present case shows that cessation of the habitual intake of nuts only for 3 days could lead to onset of CTLN2.