Hoshino Yumi, Yamazaki Masashi, Mochizuki Yusuke, Makishita Hideo, Yoshida Kunihiro
Department of Neurology and Rheumatology, Shinshu University Hospital.
Department of Neurology, Hokushin General Hospital.
Rinsho Shinkeigaku. 2020 Aug 7;60(8):520-526. doi: 10.5692/clinicalneurol.60.cn-001395. Epub 2020 Jul 7.
A 46 year-old man with schizophrenia had taken several anti-psychotic drugs since 25 years of age. From ~35 years of age, he noticed occasional neck torsion to the left, and later an ataxic gait; both symptoms gradually worsened. On admission, the patient was taking olanzapine (5 mg/day) and biperiden hydrochloride (1 mg/day) because his schizophrenia was well controlled. His parents were not consanguineous, and there was no family history of neuropsychiatric diseases. On neurological examination, he showed mild cognitive impairment, saccadic eye pursuit with horizontal gaze nystagmus, mild dysarthria, dystonic posture and movement of the neck, incoordination of both hands, and an ataxic gait. Deep tendon reflexes were normal except for the patellar tendon reflex, which was exaggerated bilaterally. Pathological reflexes were negative and there was no sign of rigidity, sensory disturbance or autonomic dysfunction. Ophthalmological examinations detected thinning of the outer macula lutea in both eyes, indicative of macular dystrophy. After admission, all anti-psychotic drugs were ceased, but his dystonia was unchanged. Levodopa and trihexyphenidyl hydrochloride were not effective. General blood, urine and cerebrospinal fluid examinations showed no abnormalities. Brain MRI showed cerebellar atrophy and bilateral symmetrical thalamic lesions without brainstem atrophy or abnormal signals in the basal ganglia. I-IMP SPECT also revealed a decreased blood flow in the cerebellum. Genetic screening, including whole exome sequencing conducted by the Initiative on Rare and Undiagnosed Disease identified no possible disease-causing variants. The patient's dystonia worsened and choreic movements manifested on his right hand and foot. We suspected dystonia with marked cerebellar atrophy (DYTCA), but could not exclude drug-induced dystonia. Macular dystrophy and bilateral thalamic lesions on brain MRI have not been previously described in DYTCA. Whether these features might be primarily associated with dystonia or cerebellar ataxia now remains to be determined.
一名46岁的精神分裂症男性自25岁起服用多种抗精神病药物。从35岁左右开始，他偶尔注意到颈部向左扭转，后来出现共济失调步态；两种症状逐渐加重。入院时，由于他的精神分裂症得到良好控制，患者正在服用奥氮平（5毫克/天）和盐酸苯海索（1毫克/天）。他的父母非近亲结婚，且无神经精神疾病家族史。神经系统检查显示，他有轻度认知障碍、水平凝视眼震时的眼球跳动性追踪、轻度构音障碍、颈部肌张力障碍姿势和运动、双手不协调以及共济失调步态。除双侧髌腱反射亢进外，深腱反射正常。病理反射阴性，无强直、感觉障碍或自主神经功能障碍的体征。眼科检查发现双眼黄斑外层变薄，提示黄斑营养不良。入院后，所有抗精神病药物均停用，但他的肌张力障碍未改变。左旋多巴和盐酸苯海索无效。血常规、尿常规和脑脊液检查均无异常。脑部MRI显示小脑萎缩和双侧对称性丘脑病变，无脑干萎缩或基底节异常信号。I-IMP SPECT也显示小脑血流减少。包括罕见和未确诊疾病倡议组织进行的全外显子组测序在内的基因筛查未发现可能的致病变异。患者的肌张力障碍加重，右手和右脚出现舞蹈样动作。我们怀疑是伴有明显小脑萎缩的肌张力障碍（DYTCA），但不能排除药物性肌张力障碍。脑部MRI上的黄斑营养不良和双侧丘脑病变以前在DYTCA中未被描述过。这些特征是否可能主要与肌张力障碍或小脑共济失调相关，目前仍有待确定。
