Liver transplantation in rare late‐onset ornithine transcarbamylase deficiency with central nervous system injury: A case report and review of the literature

Abstract

Background Ornithine transcarbamylase deficiency (OTCD) is a genetic metabolic disease. Its clinical manifestations are mainly central nervous system dysfunction caused by high blood ammonia. Late‐onset OTCD combined with central nervous system injury has a poor therapeutic response, which is one of the main factors affecting the prognosis and quality of life of patients. liver transplantation (LT) has gradually become a radical treatment for OTCD, which has achieved good results. However, there is no consensus on the timing of LT and problems of nervous system damage and repair. Methods We report the development of late‐onset OTCD with central nervous system injury in an 11‐year‐old child who received liver transplantation at our transplant center. His first symptoms were nonprojectile vomiting, followed by irritability and disturbance of consciousness, after which the disease progressed rapidly and finally resulted in a coma. After liver transplantation, the child's consciousness returned to normal, muscle strength of the limbs gradually recovered from grade 0 to grade 4, and muscle tone gradually recovered from grade 4 to grade 1, suggesting that the motor nerves had gradually recovered. However, the child is currently mentally retarded, and the language center has not yet fully recovered.At the same time, we made a literature review of OTCD. Conclusion For OTCD patients with central nervous system injury, liver transplantation can fundamentally solve the problem of ammonia metabolism in the liver and avoids further damage to the central nervous system caused by hyperammonemia. At the same time, children's nervous systems are in the developmental stage when neuroplasticity is greatest. If liver transplantation is performed as soon as possible, nerve repair is still possible.

Diagnostic and Management Issues in Patients with Late-Onset Ornithine Transcarbamylase Deficiency

“…Laboratory investigations may only be diagnostic during an acute, symptomatic phase, therefore increasing the importance of a genetic diagnosis [ 12 , 27 ]. Approximately 80–90% of cases are detected through a mutation analysis [ 25 , 27 , 41 , 42 ].…”

“…For acute management, three points are to be considered—the removal of ammonia, reversing the catabolic state and avoiding exogenous protein and the initiation of nitrogen scavengers [ 4 , 12 , 27 , 30 , 35 , 43 , 67 , 68 ].…”

“…The most prevalent UCD is an ornithine transcarbamylase deficiency (OTCD) [ 8 , 9 , 10 , 11 ]. The anabolic OTC enzyme is responsible for the transfer of a carbamoyl group from carbamoyl phosphate to the amino group of L-ornithine, producing citrulline in an early step of the urea cycle [ 12 , 13 ].…”