Adult-onset type II
citrullinemia (CTLN2), an autosomal recessive disorder caused by a mutation in the SLC25A13 gene, is characterized by increased serum
citrulline and
ammonia levels. Patients with CTLN2 also display various neuropsychiatric symptoms. Many individuals with CTLN2 are fond of
protein-rich and/or
lipid-rich foods with an aversion to
carbohydrate-rich foods. We herein report two cases of CTLN2 treated with living donor
liver transplantation (LDLT) and provide a review of the pertinent literature. Case 1 was a 43-year-old man admitted to our hospital for repetitive episodes of consciousness disturbance. Case 2 was a 37-year-old man admitted to our hospital because of abnormal behavior associated with
hyperammonemia. A definitive diagnosis of CTLN2 was accomplished by
DNA analysis in both patients, who successfully underwent LDLT using liver segments from donor siblings with confirmed heterozygous gene expression. Case 2 also underwent
conservative therapy with
arginine and a high-fat,
carbohydrate-restricted diet prior to LDLT. Postoperative recovery was uneventful and food was unrestricted in both patients. We also identified 77 cases of CTLN2 in the literature and reviewed them in terms of outcome of both
liver transplantation and
conservative therapy. The survival rate in patients treated by
liver transplantation was 100%, whereas that in patients treated by
conservative treatment showed improvement from 39.5% to 76.5% over the years.
Liver transplantation is a practical treatment that fundamentally improves patient quality of life after
transplantation. However, recent studies have suggested that
arginine and
sodium pyruvate administration combined with intensive
nutritional support is also an effective
therapy for CTLN2. Further development of
conservative therapy may provide a safer, more affordable alternative to
liver transplantation in the near future.