Ogier de Baulny H, Saudubray J M
Service de Neuropédiatrie, Maladies Métaboliques, Hôpital Robert Debré, Paris, France.
Semin Neonatol. 2002 Feb;7(1):65-74. doi: 10.1053/siny.2001.0087.
Branched chain organic acidurias are a group of disorders that result from an abnormality of specific enzymes involving the catabolism of branched chain amino acids (leucine, isoleucine, valine). Maple syrup urine disease (MSUD), isovaleric acidaemia (IVA), propionic aciduria (PA) and methylmalonic aciduria (MMA) represent the most commonly encountered abnormal organic acidurias. All these four disorders present in neonates as a neurologic distress of the intoxication type with either ketosis or ketoacidosis and hyperammonaemia. There is a free interval between birth and clinical symptoms. MMA, PA and IVA present with a severe dehydration, leuconeutropenia and thrombopenia which can mimic sepsis. All these disorders can be diagnosed by identifying acylcarnitine and other organic acid compounds in plasma and urine by gas chromatography mass spectrometry or tandem MS-MS. These disorders are amenable to treatment by removing toxic compounds and by using special diets and carnitine.
支链有机酸尿症是一组由于涉及支链氨基酸（亮氨酸、异亮氨酸、缬氨酸）分解代谢的特定酶异常而导致的疾病。枫糖尿症（MSUD）、异戊酸血症（IVA）、丙酸尿症（PA）和甲基丙二酸尿症（MMA）是最常见的异常有机酸尿症。这四种疾病在新生儿期均表现为中毒型神经功能障碍，伴有酮血症或酮症酸中毒以及高氨血症。出生与临床症状之间存在一段无症状期。甲基丙二酸尿症、丙酸尿症和异戊酸血症表现为严重脱水、白细胞减少和血小板减少，可类似败血症。所有这些疾病都可以通过气相色谱 - 质谱法或串联质谱 - 质谱法鉴定血浆和尿液中的酰基肉碱及其他有机化合物来诊断。这些疾病可通过去除有毒化合物、采用特殊饮食和使用肉碱进行治疗。
