甲基丙二酸血症临床诊治研究进展

Progresses of clinical diagnosis and therapy in methylmalonic academia

甲基丙二酸血症是先天性有机酸代谢异常中最常见的疾病,为常染色体隐性遗传,临床表现无特异性,以喂养困难、反复呕吐及嗜睡、惊厥、运动障碍等神经系统症状为主。诊断依靠串联质谱检测血酰基肉碱和气相色谱-质谱检测尿甲基丙二酸。维生素B12治疗有效并伴有同型半胱氨酸血症的患儿,治疗以维生素B12、左旋肉碱和甜菜碱为主,预后较好;维生素B12治疗无效型患儿,给予去除异亮氨酸、缬氨酸、苏氨酸和蛋氨酸的特殊配方奶粉及左旋肉碱治疗为主,预后较差。

Methylmalonic acidosis is the most common disease of congenital organic acid metabolic disorders,and it is an autosomal recessive disease.The cinical manifestations of Methylmalonic acidosis is no specific.It is characterized by feeding difficulties,recurrent vomiting and the neurological symptoms such as lethargy,convulsion,movement disorders,and so on.Diagnosis of the disease depends on the measurement of acylcarnitines in the blood by tandem mass spectrometry and the detection of methylmalonic acid in the urine by gas-chromatography mass spectrometry.The vitamin B12-responsive patients with methylmalonic acidemia and homocystinuria should be mainly treated with vitamin B12,L-carnitine and betaine,while the vitamin B12-nonresponsive patients should be treated with protein restriction,the special milk formula without isoleucine,valine,threonine and methionine,as well as the L-carnitine.Compared with the vitamin B12-nonresponsive patients,the vitamin B12-responsive ones have better outcome.