鸟氨酸氨甲酰转移酶缺乏症患者临床资料及质谱检测结果分析

Clinical characteristics and analysis of mass spectrometric data in patients with ornithine transcarbamylase deficiency

目的 分析鸟氨酸氨甲酰转移酶缺乏症（OTCD）患者临床表现及生化特点,以便提高临床医师对此病的认识.方法 分析2005至2013年上海交通大学医学院附属新华医院确诊的40例OTCD患者的临床表现、血氨水平、串联质谱检测的血瓜氨酸水平及气相色谱质谱检测的尿乳清酸、尿嘧啶水平,并与25名健康儿童进行比较分析.结果 OTCD患者40例,发病年龄中位数为1.4岁（3 d～29岁）,临床表现主要为喂养困难、持续性呕吐、抽搐、意识障碍、高氨血症等.患者血瓜氨酸水平显著低于对照组[6.35 （1.84 ～21.11）比13.65（10.23 ～ 24.52） μmol/L,P＜0.05].尿乳清酸及尿嘧啶水平显著高于对照组[167.77 （1.21 ～1 650.45）比0.25（0～2.32） mmol/molCr、52.67（3.50 ～338.64）比0.69（0～2.87） mmol/molCr,均P＜0.05].结论 对于血氨增高的患者,串联质谱检测血瓜氨酸降低,尿气相色谱质谱检测乳清酸及尿嘧啶升高有助于OTCD诊断.

Objective To explore the clinical manifestations and biochemical characteristics of patients with ornithine transcarbamylase deficiency （OTCD） so as to increase the clinician awareness for this disease.Methods The clinical manifestations,blood ammonia levels,citrulline levels,urinary orotic acid and uracil levels were analyzed for 40 patients with OTCD from 2005 to 2013.And comparisons were made with 25 healthy children.Results Among them,the median age of onset was 1.4 years （3 days-29 years）.The major clinical manifestations were feeding difficulties,persistent vomiting,convulsions,unconsciousness and hyperammonemia,etc.The blood levels of citrulline in these patients were significantly lower than those of the control group （6.35 （1.84-21.11） vs 13.65 （10.23-24.52） μmol/L,P ＜ 0.05）.The urinary levels of orotic acid and uracil in these patients were significantly higher than those in the control group （167.77（1.21-1 650.45） vs 0.25（0-2.32） mmol/molCr,52.67（3.50-338.64） vs 0.69（0-2.87） mmol/molCr,P ＜0.05）.Conclusion For patients with hyperammonemia,the decreased levels of citrulline in blood tested by tandem mass spectrometry and increased orotic acid and uracil in urine on gas chromatography-mass spectrometry may aid the diagnosis OTCD.