BACKGROUND Pathogenic variants in the dynamin 1 like gene are related to abnormal mitochondrial dynamics and distributions and are associated to variable clinical phenotypes. A few patients harboring the p.Arg403Cys missense variant appears to be different from the classical, more severe phenotypes, showing sudden onset of drug resistant seizures after a previously normal or slightly delayed development. CASE REPORT We report on a boy with abrupt onset of focal status and coma at the age of 13, initially treated as autoimmune encephalitis, with final diagnosis of de novo missense p.Arg403Cys variant in the DNM1L gene. DISCUSSION We compare his clinical, electrophysiological, biochemical, neuroradiological and histopathological picture to the rare cases reported to date and provide diagnostic clues that can help clinicians in differentiate p.Arg403Cys-related phenotype from that of immune-mediated encephalopathies. CONCLUSION The clinical picture related to p.Arg403Cys mutations should be considered alongside acquired pathologies in the differential diagnosis of young patients with focal refractory epilepsy and encephalopathy, also occurring during late childhood or adolescence. Prompt genetic testing allows to avoid unnecessary treatments and procedures and to better define the prognosis and management strategies.

中文翻译：

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一名 13 岁男孩 DNM1L 新发突变的局灶状态和急性脑病：视频测谎模式和鉴别诊断线索

背景 dynamin 1 样基因中的致病变异与异常的线粒体动力学和分布有关，并且与可变的临床表型有关。一些携带 p.Arg403Cys 错义变异的患者似乎不同于经典的更严重的表型，在先前正常或稍微延迟的发育后突然出现耐药性癫痫发作。病例报告 我们报告了一名男孩在 13 岁时突然出现局灶性状态和昏迷，最初被治疗为自身免疫性脑炎，最终诊断为 DNM1L 基因中的新错义 p.Arg403Cys 变异。讨论 我们将他的临床、电生理、生化、神经放射学和组织病理学图片与迄今为止报告的罕见病例进行比较，并提供诊断线索，帮助临床医生区分 p。来自免疫介导脑病的 Arg403Cys 相关表型。结论 与 p.Arg403Cys 突变相关的临床表现应与获得性病理学一起考虑，以鉴别诊断患有局灶性难治性癫痫和脑病的年轻患者，也发生在儿童晚期或青春期。及时的基因检测可以避免不必要的治疗和程序，并更好地确定预后和管理策略。