Pathogenesis and diagnostic difficulties of multiple acyl-CoA dehydrogenase deficiency
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.