To define the phenotypic spectrum of isolated sulfite oxidase (ISOD) and molybdenum cofactor deficiency (MoCD), aiming to promote timely diagnosis and assist in future clinical trial design.

We analyzed clinical, radiographic, biochemical, and genetic data from 146 patients reported in the literature.

We stratified patients into 2 phenotypic subgroups based on clinical and radiographic characteristics. In the first (Class I), patients presented early in life (age 1–50 days) with acute onset of neurologic symptoms and development of diffuse brain injury with cystic leukomalacia. Patients in the second subgroup (Class II) presented later in life (age 30 days–23 years) with prominent movement abnormalities and selective injury of the basal ganglia and cerebellum. A significant difference in survival estimates correlated with milder disease severity among Class II patients. Substantial overlap in sulfur-containing metabolite levels prevented discrimination of subgroups based on diagnostic biomarkers, but genotype-phenotype correlations suggested that residual SUOX activity may contribute to milder phenotypes.

Patients with SUOX and MoCD gravitate toward 1 of 2 distinct clinicoradiographic profiles. Patient stratification may help promote accurate diagnosis, prognostication, and aid in the design of future clinical trials.

明确分离亚硫酸盐氧化酶（ISOD）和钼辅因子缺乏症（MoCD）的表型谱，旨在促进及时诊断并协助未来的临床试验设计。

我们分析了文献中报道的 146 名患者的临床、放射学、生化和遗传数据。

我们根据临床和放射学特征将患者分为 2 个表型亚组。第一种（I 类）患者在生命早期（1-50 天）就出现神经系统症状急性发作，并出现弥漫性脑损伤并伴有囊性白质软化症。第二亚组（II 类）患者在晚年（年龄 30 天至 23 岁）出现明显的运动异常以及基底神经节和小脑的选择性损伤。 II 类患者中生存估计的显着差异与较轻的疾病严重程度相关。含硫代谢物水平的大量重叠阻止了基于诊断生物标志物的亚组区分，但基因型-表型相关性表明残留的 SUOX 活性可能导致较温和的表型。

SUOX 和 MoCD 患者倾向于两种不同的临床放射学特征中的一种。患者分层可能有助于促进准确的诊断、预测，并有助于设计未来的临床试验。