LIVER-TRANSPLANTATION FOR THE TREATMENT OF UREA CYCLE DISORDERS

The principal goal of therapy when liver transplantation Is used for t he treatment of metabolic disease is to correct the metabolic error. B y doing so, liver transplantation eliminates the hepatic and periphera l consequences of the error. Inborn errors involving the urea cycle ap pear on theoretical grounds to be amenable to treatment using liver tr ansplantation and, indeed, published data demonstrate that this approa ch to therapy can be successful. The purpose of this study is to exami ne the outcome of liver transplantation done for the indication of ure a cycle defects in a large group of patients. The first goal of the st udy is to determine with certainty that liver transplantation corrects hyperammonaemia and halts the progress of disease. A second goal is t o determine the extent of neurological recovery In children previously injured by hyperammonaemia. The final goal is to understand whether t he quality of life is improved and medical expense is reduced by trans plantation. The study Involved a survey of major transplantation centr es. Four centres provided data about 16 patients, 14 of whom were aliv e 11 months to 6 years after transplantation. The results demonstrate that liver transplantation resulted in correction of hyperammonaemia i n all patients. The neurological outcome after transplantation correla ted closely with the condition prior to transplantation. This populati on of patients has had relatively few problems in the long term relate d to the liver transplant itself. The quality of life seems to be much improved, but further study will be needed to confirm this. Limited d ata involving two patients show a reduction in the cost of care. We co nclude from our experience that liver transplantation can be an effect ive treatment for children with urea cycle defects.