Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, 500-1194, Japan.
Division of Clinical Genetics, Gifu University Hospital, Gifu, Japan.
J Hum Genet. 2019 Feb;64(2):99-111. doi: 10.1038/s10038-018-0524-x. Epub 2018 Nov 5.
Beta-ketothiolase (mitochondrial acetoacetyl-CoA thiolase, T2) deficiency (OMIM #203750, *607809) is an inborn error of metabolism that affects isoleucine catabolism and ketone body metabolism. This disorder is clinically characterized by intermittent ketoacidotic crises under ketogenic stresses. In addition to a previous 26-case series, four series of T2-deficient patients were recently reported from different regions. In these series, most T2-deficient patients developed their first ketoacidotic crises between the ages of 6 months and 3 years. Most patients experienced less than three metabolic crises. Newborn screening (NBS) for T2 deficiency is performed in some countries but some T2-deficient patients have been missed by NBS. Therefore, T2 deficiency should be considered in patients with severe metabolic acidosis, even in regions where NBS for T2 deficiency is performed. Neurological manifestations, especially extrapyramidal manifestations, can occur as sequelae to severe metabolic acidosis; however, this can also occur in patients without any apparent metabolic crisis or before the onset of metabolic crisis.
β-酮硫解酶（线粒体乙酰乙酰辅酶 A 硫解酶，T2）缺乏症（OMIM#203750，*607809）是一种先天性代谢错误，影响异亮氨酸分解代谢和酮体代谢。这种疾病的临床特征是在生酮应激下间歇性酮症酸中毒危象。除了之前的 26 例系列报道，最近来自不同地区的又有四个 T2 缺乏症患者系列报道。在这些系列中，大多数 T2 缺乏症患者在 6 个月至 3 岁之间出现第一次酮症酸中毒危象。大多数患者经历的代谢危象少于三次。一些国家对 T2 缺乏症进行了新生儿筛查（NBS），但有些 T2 缺乏症患者被 NBS 漏诊。因此，即使在进行 T2 缺乏症 NBS 的地区，对于严重代谢性酸中毒的患者，也应考虑 T2 缺乏症。神经表现，特别是锥体外系表现，可作为严重代谢性酸中毒的后遗症发生；然而，这也可能发生在没有明显代谢危机或代谢危机发作之前的患者中。
