Rábano J A, Playan A, Guirado F, Montoya J, Baldellou A, López-Pisón J
Sección de Neuropediatría, Hospital Miguel Servet, Zaragoza, España.
Rev Neurol. 1998 Dec;27(160):1005-7.
Deletions of mitochondrial DNA (mtDNA) are a known cause of various mitochondrial cytopathies, which are sporadic and usually not due to maternal transmission. The multiple deletions are usually transmitted on a Mendelian pattern, and are frequently of autosomal dominant character. Leukodystrophy may be part of the picture, or even the form of presentation, of some mitochondrial cytopathies. Thus, in a case of leukoencephaly of unknown origin, mitochondrial cytopathy should be considered in the differential diagnosis.
We present the case of a boy with no previous clinical abnormalities who, at the age of 13, suddenly fell to the floor with an encephalopathy which required aggressive treatment, needing mechanical ventilation and prolonged sedation. Following partial recovery spastic-dystonic quadriplegia remained. Neuroimaging showed advanced leukodystrophy with small hemorrhages in the white matter, which later disappeared. After rejecting other aetiologies, mitochondrial cytopathies in muscle were studied. A partial defect of the I and IV complexes of the respiratory chain and two deletions of mtDNA were shown.
This case is another example of the variable clinical presentation of mitochondrial cytopathies and yet another argument for their inclusion in the diagnosis of leukodystrophy of unknown origin.
线粒体DNA（mtDNA）缺失是各种线粒体细胞病的已知病因，这些疾病为散发性，通常并非母系遗传。多重缺失通常按孟德尔模式遗传，且常具有常染色体显性特征。脑白质营养不良可能是某些线粒体细胞病的一部分，甚至是其表现形式。因此，在病因不明的脑白质病病例中，鉴别诊断时应考虑线粒体细胞病。
我们报告一例此前无临床异常的男孩病例，该男孩13岁时突然因脑病摔倒在地，需要积极治疗，包括机械通气和长时间镇静。部分恢复后，痉挛性肌张力障碍性四肢瘫持续存在。神经影像学显示进展性脑白质营养不良，白质内有小出血灶，随后出血灶消失。排除其他病因后，对肌肉进行了线粒体细胞病研究。结果显示呼吸链复合体I和IV存在部分缺陷以及两个mtDNA缺失。
该病例是线粒体细胞病临床表现多样的又一实例，也是将其纳入病因不明的脑白质营养不良诊断的又一依据。
