Zhao Zhanqi, Chu Chan-Ching, Chang Mei-Yun, Chang Hao-Tai, Hsu Yeong-Long
Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany Division of Respiratory Therapy Division of Chest Medicine, Department of Internal Medicine, Far Eastern Memorial Hospital, Ban-Chiao District, New Taipei City, Taiwan.
Medicine (Baltimore). 2018 Jun;97(25):e11162. doi: 10.1097/MD.0000000000011162.
Methylmalonic acidemia (MMA) is an autosomal recessive disease of organic acidemia.
We report a 26-year-old male who presented with metabolic acidosis, acute renal failure required hemodialysis and acute respiratory failure required mechanical ventilation support. Progressive hypotonia of muscles made weaning from mechanical ventilator difficult.
High level of serum methylmalonic acid and the mut genotype sequences confirmed the diagnosis of this adult-onset MMA. Two mut genotype sequences were found by analyzing all coding exons and exon-intron junctions. One genotype was well documented (Exon 6 Mutation, c. 1280G>A. p. G427D, heterozygous). The other mut genotype sequence had never been reported elsewhere (Intron 6 Novel, c. 1333-13_c. 1333-8delTTTTTC, heterozygous).
Diet modification, medication, regular hemodialysis and physical rehabilitation. Weaning strategy adjusted with help of electrical impedance tomography.
The muscle power of the patient gradually recovered. Extubation of the patient was successful and he was discharged without oxygen required.
This case gives us the lesson that MMA can be newly diagnosed in adult patient. A new mut genotype sequence was discovered. The use of electrical impedance tomography to select a suitable method for inspiratory muscle training was possible and useful.
甲基丙二酸血症（MMA）是一种常染色体隐性遗传的有机酸血症疾病。
我们报告一名26岁男性，他出现代谢性酸中毒、需要血液透析的急性肾衰竭以及需要机械通气支持的急性呼吸衰竭。肌肉进行性肌张力减退使得脱机困难。
血清甲基丙二酸水平升高以及mut基因型序列确诊了该成年发病型MMA。通过分析所有编码外显子和外显子 - 内含子连接点发现了两个mut基因型序列。一个基因型有详细记录（外显子6突变，c.1280G>A，p.G427D，杂合子）。另一个mut基因型序列在其他地方从未有过报道（内含子6新发突变，c.1333 - 13_c.1333 - 8delTTTTTC，杂合子）。
饮食调整、药物治疗、定期血液透析和身体康复。借助电阻抗断层扫描调整脱机策略。
患者肌肉力量逐渐恢复。患者成功拔管，出院时无需吸氧。
该病例让我们认识到MMA可在成年患者中初次诊断。发现了一种新的mut基因型序列。使用电阻抗断层扫描来选择合适的吸气肌训练方法是可行且有用的。
