Abstract: Multiple acyl-CoA Dehydrogenase Deficiency （MADD）， also known as glutaric aciduria type II， is an autosomal recessive genetic disease caused by a gene defect encoding electron-transporting flavoprotein or electron-transporting flavoprotein dehydrogenase. The disease mainly affects the β-oxidation of fatty acids and specific amino acids and the metabolism of choline. MADD is subdivided into three categories based on the differences in onset time and clinical manifestations. Type Ⅰ has a neonatal onset and is accompanied by congenital malformations. Type Ⅱ has a neonatal onset and is not accompanied by congenital malformations. Type Ⅲ has a late onset， diverse symptoms， and the majority of cases carry ETFDH mutations and respond well to riboflavin treatment. The diagnosis of MADD is mainly based on the blood acylcarnitine spectrum， urine organic acid spectrum and genetic analysis. However， due to the lack of specific symptoms and signs in MADD patients， the clinical diagnosis remains challenging. Starting from the pathogenesis and clinical phenotype of MADD， this review presents a detailed description of diagnostic difficulties and key points， with the objective of enhancing our knowledge of this disease and increasing diagnostic efficiency.

Key words: multiple acyl -CoA dehydrogenase deficiency, pathogenesis, diagnosis

摘要： 多种酰基辅酶A脱氢酶缺乏症（multiple acyl-CoA dehydrogenase deficiency，MADD），又称戊二酸尿症Ⅱ型，是一种由编码电子转移黄素蛋白或电子转移黄素蛋白脱氢酶的基因缺陷引起的常染色体隐性遗传病，主要影响脂肪酸和特定氨基酸的β-氧化以及胆碱的代谢。根据发病时间与临床表现的差异，MADD被划分为3型：Ⅰ型新生儿起病，伴有先天畸形；Ⅱ型新生儿起病，不伴先天畸形；Ⅲ型起病晚，症状多样，大多携带ETFDH突变，对核黄素治疗反应良好。血酰基肉碱谱、尿有机酸谱及基因分析是MADD诊断的重要手段，但由于MADD患者缺乏特异性的症状与体征，临床诊断仍充满挑战性。文章从MADD的发病机制和临床表型出发，对该病诊断的难点和要点做了较为详细的评述，旨在加强对该病的认识，提高诊断效率。

关键词: 多种酰基辅酶A脱氢酶缺乏症, 发病机制, 诊断