迟发型鸟氨酸氨甲酰转移酶缺乏症的医学营养治疗及随访

Medical nutrition management and follow-up of patients with late-onset ornithine transcarbamylase deficiency

目的探讨6例迟发型鸟氨酸氨甲酰转移酶(OTC)缺乏症患儿的临床特点及医学营养治疗效果。方法回顾性分析2020年1月至2022年4月在南京医科大学附属儿童医院临床营养科进行长期医学营养管理的6例迟发型OTC缺乏症患儿的临床表现、实验室检查、基因检测结果以及医学营养治疗情况。结果 6例患儿均有不同程度的肝功能损害, 血氨水平均明显增高(172.1~348.0 μmol/L)。3例患儿血瓜氨酸水平降低(3.95~5.43 μmol/L)。3例患儿尿乳清酸水平明显增高(123.48~342.60 mmol/mol肌酐);4例患儿尿嘧啶水平明显增高(106.77~1 207.26 mmol/mol肌酐)。6例患儿均检测到OTC基因变异, 分别为c.364G>C p.(E122Q)、c.1028C>G p.(T343R)、c.664-2(IVS6)A>C、c.635G>T p.(G212V)、c.929c.931delAAG p.(E310del)、c.829C>T p.(R277W)。6例患儿均予个体化医学营养方案管理及长期随访, 随访期间3例发生低蛋白血症、急性代谢危象和生长迟缓, 3例生长发育及实验室指标均正常, 1例饮食干预3个月后行肝移植治疗。结论 OTC缺乏症患儿临床表现缺乏特异性, 血氨基酸谱、尿有机酸分析及基因检测对诊断有重要意义。长期合理医学营养管理有助于改善患儿预后和生存质量。

Objective To explore the clinical characteristics and medical nutritional therapy of 6 patients with late-onset ornithine transcarbamylase(OTC)deficiency.Methods The clinical features,biochemical data,gene variations and treatment outcomes of 6 children with late-onset OTC deficiency admitted to the Department of Clinical Nutrition,Children′s Hospital of Nanjing Medical University from January 2020 to April 2022 were retrospectively analyzed.The 6 patients were all intervened by a long-term medical nutrition management.Results Liver dysfunction and hyperammonemia(172.1-348.0μmol/L)were found in all the 6 children with late-onset OTC deficiency.Serum citrulline decreased in 3 patients(3.95-5.43μmol/L).Three patients showed increased urine orotic acid(123.48-342.60 mmol/mol Cr).Urine uracil increased in 4 patients(106.77-1207.26 mmol/mol Cr).Variations of the OTC gene[c.364G>C p.(E122Q),c.1028C>G p.(T343R),c.664-2(IVS6)A>C,c.635G>T p.(G212V),c.929_c.931delAAG p.(E310del),c.829C>T p.(R277W)]were identified in all patients.The 6 children were all managed by individualized medical nutrition program and followed up for a long time.During the follow-up period,3 cases developed hypoproteinemia,acute metabolic crisis and growth retardation,3 cases had normal growth and laboratory indicators,and 1 case received liver transplantation after 3 months of nutritional management.Conclusions The clinical manifestations of OTC deficiency are non-specific.Blood amino acids,urine organic acids and genetic tests are important for the diagnosis.Long-term regular medical nutrition management is helpful to improve the prognosis and quality of life of children.