[Adult-onset type II citrullinemia in a patient undergoing continuous ambulatory peritoneal dialysis]

A 57-year-old Japanese man was admitted to Toyama Medical & Pharmaceutical University Hospital with delirium and flapping tremor on April 2, 1997. He had been undergoing continuous ambulatory peritoneal dialysis (CAPD) because of diabetic nephropathy since 1993. Blood chemistry showed slightly elevated plasma ammonia level with no evidence of liver injury, and his portal venography revealed no port-systemic shunt. He was diagnosed as having type II citrullinemia because of an elevated citrulline level on amino acid analysis and very low hepatic argininosuccinate synthetase activity obtained from biopsy specimen of liver. In this case, plasma concentrations of ammonia and citrulline were not so high as those in previously reported cases, although the hepatic argininosuccinate synthetase activity was actually less than 10% of the control value. Owing to CAPD, he was conservatively controlled in a relatively good condition. This indicates that CAPD seems to be a useful therapeutic approach for citrullinemia since liver transplantation is still difficult in Japan.