Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Pisa, Italy.
Unit of Neurology, San Luca Hospital, Lucca, Italy.
J Neurol. 2022 Mar;269(3):1413-1421. doi: 10.1007/s00415-021-10697-1. Epub 2021 Jul 14.
Both prevalence and clinical features of the various movement disorders in adults with primary mitochondrial diseases are unknown.
Based on the database of the "Nation-wide Italian Collaborative Network of Mitochondrial Diseases", we reviewed the clinical, genetic, neuroimaging and neurophysiological data of adult patients with primary mitochondrial diseases (n = 764) where ataxia, myoclonus or other movement disorders were part of the clinical phenotype.
Ataxia, myoclonus and movement disorders were present in 105/764 adults (13.7%), with the onset coinciding or preceding the diagnosis of the mitochondrial disease in 49/105 (46.7%). Ataxia and parkinsonism were the most represented, with an overall prevalence at last follow-up of 59.1% and 30.5%, respectively. Hyperkinetic movement disorders were reported in 15.3% at last follow-up, being the less common reported movement disorders. The pathogenic m.8344A > G and POLG variants were always associated with a movement disorder, while LHON variants and mtDNA single deletions were more commonly found in the subjects who did not present a movement disorder. The most common neuroimaging features were cortical and/or cerebellar atrophy, white matter hyperintensities, basal ganglia abnormalities and nigro-striatal degeneration. Almost 70% of patients with parkinsonism responded to dopaminergic therapy, mainly levodopa, and 50% with myoclonus were successfully treated with levetiracetam.
Movement disorders, mainly ataxia and parkinsonism, are important findings in adult primary mitochondrial diseases. This study underlies the importance of looking for a mitochondrial etiology in the diagnostic flowchart of a movement disorder and may help direct genetic screening in daily practice.
原发性线粒体疾病成人患者的各种运动障碍的患病率和临床特征尚不清楚。
基于“全国意大利线粒体疾病协作网络”数据库，我们回顾了原发性线粒体疾病成人患者（n=764 例）的临床、遗传、神经影像学和神经生理学数据，其中共济失调、肌阵挛或其他运动障碍是其临床表现的一部分。
105/764 名成人（13.7%）存在运动障碍，其中 49/105 名（46.7%）的运动障碍与线粒体疾病的诊断同时或之前发生。共济失调和帕金森病最为常见，末次随访时的总体患病率分别为 59.1%和 30.5%。末次随访时报告的高运动障碍发生率为 15.3%，是较少见的报告运动障碍。致病性 m.8344A>G 和 POLG 变异总是与运动障碍相关，而 LHON 变异和 mtDNA 单一缺失在没有运动障碍的患者中更为常见。最常见的神经影像学特征是皮质和/或小脑萎缩、白质高信号、基底节异常和黑质纹状体变性。近 70%的帕金森病患者对多巴胺能治疗有反应，主要是左旋多巴，50%的肌阵挛患者用左乙拉西坦成功治疗。
运动障碍，主要是共济失调和帕金森病，是成人原发性线粒体疾病的重要表现。本研究强调了在运动障碍的诊断流程图中寻找线粒体病因的重要性，并可能有助于在日常实践中指导基因筛查。
