Higashimoto Tomoyasu, Whitehead Matthew T, MacLeod Erin, Starin Danielle, Regier Debra S
National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States of America.
Division of Radiology, Children's National Hospital, Washington, DC, United States of America.
Mol Genet Metab Rep. 2022 Jun 18;32:100886. doi: 10.1016/j.ymgmr.2022.100886. eCollection 2022 Sep.
Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disease resulting in impaired or absent breakdown of branched-chain amino acids (BCAA) valine, isoleucine, and leucine. Classic MSUD often presents in post-natal periods, at times before newborn screening results, and is treated with a protein restricted diet supplemented with medical food and close follow up to prevent toxic buildup of blood leucine. Acute episodes of decompensation are prevented by early recognition and treatment. Acute episodes of metabolic decompensation in patients with MSUD are medical emergencies that require immediate treatments as cerebral edema may lead to brain-stem compression resulting in death. As the early outcomes improve for MSUD patients, the long-term sequelae of chronic hyperleucemia are being elucidated and include cognitive impairment, mental health disorders, and movement disorders. In this report we present an adult patient with MSUD with attention deficit, hyperactivity type (ADHD) and depression due to prolonged exposure to elevated leucine managed with community support services who presented to the emergency department with new onset of acute hallucinations. He was held in the emergency department awaiting involuntary commitment to a psychiatric facility and underwent psychiatric treatments for suspected new onset hallucinations without improvement. Upon notification of metabolic specialists and initiation of appropriate therapy of MSUD, his leucine level normalized rapidly with resolution of his acute psychosis. This case describes the acute presentation of psychosis in the setting of long-term toxicity of leucine. This case also highlights the importance of transition of care, education and planning in patients with inborn errors of metabolism.
枫糖尿症（MSUD）是一种常染色体隐性代谢疾病，会导致支链氨基酸（BCAA）缬氨酸、异亮氨酸和亮氨酸的分解受损或缺失。典型的MSUD常在出生后发病，有时在新生儿筛查结果出来之前就已出现，治疗方法是采用蛋白质限制饮食，并辅以特殊医用食品，同时密切随访以防止血液中亮氨酸的毒性积聚。通过早期识别和治疗可预防失代偿急性发作。MSUD患者的代谢失代偿急性发作属于医疗紧急情况，需要立即治疗，因为脑水肿可能导致脑干受压，进而导致死亡。随着MSUD患者早期治疗效果的改善，慢性高亮氨酸血症的长期后遗症正在被阐明，包括认知障碍、精神健康障碍和运动障碍。在本报告中，我们介绍了一名患有MSUD的成年患者，由于长期暴露于高亮氨酸水平，出现了注意力缺陷多动障碍（ADHD）和抑郁症，在社区支持服务的管理下，该患者因新发急性幻觉而到急诊科就诊。他被留在急诊科等待非自愿送入精神病院，并接受了针对疑似新发幻觉的精神科治疗，但病情没有改善。在通知代谢专家并开始对MSUD进行适当治疗后，他的亮氨酸水平迅速恢复正常，急性精神病症状也随之消失。本病例描述了在亮氨酸长期毒性情况下精神病的急性表现。该病例还强调了先天性代谢缺陷患者护理过渡、教育和规划的重要性。
