Wilder-Smith E, Tan E K, Law H Y, Zhao Y, Ng I, Wong M C
Division of Neurology, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074, Republic of Singapore.
J Neurol Sci. 2003 Sep 15;213(1-2):25-8. doi: 10.1016/s0022-510x(03)00129-1.
The clinical spectrum of spinocerebellar ataxia 3 (SCA 3) disease is wide and varied. We describe a Chinese patient with a mutation at the SCA 3 locus with clinical features of levodopa-responsive dystonia. The family history was suggestive of being autosomally dominant. Levodopa responsiveness though rare has been described in families with features of parkinsonism. Noteworthy is the relatively late onset of disease (>40 years) possibly explained by the low number of affected alleles at 59, the usual range being from 62 to 86, with the lowest recorded number at 56. This expands the wide and varied phenotypic manifestations of SCA 3, and highlights the observation that features suggestive of levodopa-responsive dystonia (DRD) such as focal dystonia, gait difficulty with diurnal fluctuation of symptoms, and a marked response to low doses of levodopa can be presenting features of SCA 3. SCA 3 should be considered a differential diagnosis in adult patients who present with DRD phenotype and with a positive family history.
脊髓小脑共济失调3型（SCA 3）疾病的临床谱广泛且多样。我们描述了一名中国患者，其SCA 3基因座存在突变，具有左旋多巴反应性肌张力障碍的临床特征。家族史提示为常染色体显性遗传。左旋多巴反应性虽然罕见，但在具有帕金森病特征的家族中已有描述。值得注意的是，该疾病发病相对较晚（>40岁），这可能是由于59个受累等位基因数量较少所致，通常范围为62至86个，记录到的最低数量为56个。这扩展了SCA 3广泛多样的表型表现，并突出了这样的观察结果，即提示左旋多巴反应性肌张力障碍（DRD）的特征，如局灶性肌张力障碍、症状有日间波动的步态困难以及对低剂量左旋多巴有明显反应，可能是SCA 3的表现特征。对于表现出DRD表型且家族史阳性的成年患者，应考虑将SCA 3作为鉴别诊断。
