Riboflavin transporter deficiency (RTD), previously referred to as Brown-Vialetto-Van Laere syndrome, is caused by pathogenic variants in the SLC52A1, SLC52A2, or SLC52A3 genes, resulting in RTD types 1, 2, and 3, respectively. Researchers estimate an occurrence of approximately 1 in 1,000,000. There is only one case of type 1 described in medical literature. Type 2 is characterized by muscle weakness in the arms and neck, vision loss, hearing impairment, and sensory ataxia. In type 3, vocal cord paralysis is more common and muscle weakness is more generalized. In 2018, we described a case of a 6-year-old girl with RTD type 2 who made remarkable visual recovery after initiation of treatment with oral riboflavin and coenzyme Q10 supplementation. The patient's younger brother began the same treatment regimen after genetic testing confirmed that he carried the same genetic variant. In this report, we update the visual and neurologic status in these siblings 5 years after our initial report and 7.5 years after initiation of riboflavin treatment.

中文翻译：

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儿童神经病学：核黄素转运蛋白缺乏症兄弟姐妹的五年更新：持续核黄素治疗后稳定的视力和神经系统状态。


核黄素转运蛋白缺乏症 （RTD），以前称为 Brown-Vialetto-Van Laere 综合征，由 SLC52A1、SLC52A2 或 SLC52A3 基因的致病性变异引起，分别导致 RTD 1、2 和 3 型。研究人员估计大约每 1,000,000 人中就有 1 人发生。医学文献中仅描述了一例 1 型 1 型病例。2 型的特征是手臂和颈部肌肉无力、视力丧失、听力障碍和感觉性共济失调。在 3 型中，声带麻痹更常见，肌无力更普遍。2018 年，我们描述了一例患有 2 型 RTD 的 6 岁女孩，她在开始口服核黄素和辅酶 Q10 补充剂治疗后视力恢复显着。患者的弟弟在基因检测证实他携带相同的基因变异后开始了相同的治疗方案。在本报告中，我们更新了这些兄弟姐妹在初始报告后 5 年和核黄素治疗开始后 7.5 年的视觉和神经系统状态。