Living-related liver transplantation for Type II citrullinemia using a graft from heterozygote donor

Background. Type II citrullinemia (CTLN2) characterized by a liver-specific argininosuccinate synthetase deficiency is an adult onset genetical disord er caused by the mutation of SLC25A13 gene, which results in fulminant hype rammonemia often with poor prognosis. Methods. A 16-year-old Japanese boy presented fulminant hyperammonemia and encephalopathy and recovered after aggressive medical treatment. The patien t was diagnosed as CTLN2 by plasma amino acid pattern and detection of the mutated SLC25A13 gene. We performed living-related liver transplantation (L RLT) using a graft from the genetically proven heterozygote father. Results. Serum amino acid concentration was normalized within a day after t ransplantation without protein restriction and medication. The patient's po stoperative course was natural. The patient is back in school 6 months afte r surgery. Conclusions. Living-related liver transplantation using a graft from geneti cally proven heterozygote donors might be a permissible treatment modality for CTLN2. Long-term observation may be necessary to make a definite conclu sion possible.