PEDIATRICS

C. Yong¹, C. Chen¹, A.M. Concejero¹, K. Jawade¹, V. Jawade¹, B. Jawan², Y. Cheng³, H. Eng¹, A. Yap¹, D. Bora^1
1Liver Transplant Program, Department Of Surgery, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Kaohsiung/TAIWAN, ²Anesthesiology, Chang Gung Memorial Hospital, Kaohsiung/TAIWAN, ³Department Of Radiology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, KAOHSIUNG HSIEN/TAIWAN

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Background and objective: Urea cycle defect (UCD) is one of the rare inborn errors of metabolism. The role of liver transplantation has been reported sporadically in literature. We are reporting a case of living donor liver transplantation for UCD. We have also done a review of literature to study the outcome of liver transplantation for UCD. Patients and method: Clinical case records of patients were collected and reviewed. Medline database was searched using the term "urea cycle defects". The outcome of liver transplantation for UCD was studied and compared with other modalities of treatment. Result: Case report: 15-month-male baby had a history of recurrent episodes of hyperammonemia and encephalopathy with projectile vomiting since birth. He was diagnosed to have UCD and received medical treatment in the form of protein-restricted diet, sodium benzoate and citrulline malate (Stimol®, Gentilly, France). The patient also underwent peritoneal dialysis. But, he did not respond well to medical treatment. There was failure to thrive associated with episodes of hyperammonemia, hypokalemia and bronchopneumonia. He underwent living donor liver transplantation using a left lateral segment graft obtained from his mother. His postoperative course was uneventful except for the development of bilioma for which revision hepatico-jejunostomy was done. His hypokalemia improved due to stoppage of vomiting and there was no episode of hyperammonemia. Two years after transplantation, his physical growth normalized but he had signs of poor mental development. This may be due to sub-clinical neurological damage caused by episodes of hyperammonemia in the pre-transplant period. At latest follow up, 4-years after transplantation he is living an acceptable quality of life. Review of Literature: Worldwide, 51 patients of liver transplantation for UCD were reported until 2005. 40 out of 51 patients were alive at the time of meta-analysis and all of them were living good quality of life. Out of the 40 living patients, neurological impairment was persistent in 5 patients after transplantation, and the cumulative 5-year survival was 90%. There are some reports about the use of hepatocyte transplantation and gene therapy for UCD. The results are encouraging but these modalities are still in the developing phase. In our case, there was no clinical evidence of neurological damage at the time of transplantation but after transplantation his mental development is affected. We think that early transplant may have prevented this. Conclusion: Early diagnosis of UCD with early or pre-emptive liver transplantation may prevent neurological damage and improve the overall out come of liver transplantation in UCD.

Disclosure: All authors have declared no conflicts of interest.