Abstract: Objective To study the clinical features and diagnostic methods of patients with pure hereditary spastic paraplegia (HSP). Methods Patients diagnosed with pure HSP from October 2006 to February 2013 admitted to Department of Neurology, West China Hospital, Sichuan University were included. The patients were assessed by the Spastic Paraplegia Rating Scale and the clinical features were reviewed. Results Thirty-three HSP patients (21 men and 12 women) were included in the study. Thirteen patients (39.39%) had family history of HSP and the most common genetic mode of the familial cases were autosomal dominant inheritance (11/13). The mean age of onset were (20.35 ± 15.55) years and the mean disease duration were (12.77 ± 9.83) years. All of the included patients presented with signs of impairment of the pyramidal tract such as increased muscular tone, tendon hyperreflexia and positive Babinski's sign of the lower limbs. Impairment of the pyramidal tract also presented in the upper limbs in some patients. Scissors gait appeared in 29 patients and feet deformity in 5 patients. Atrophy of thoracic cord on MRI were presented in 5 patients while 2 patients complicated with peripheral nerve damage. Four patients had a novel exon 10-17 deletion in SPG4 gene. There were no differences in onset age, disease duration and mean score of the Spastic Paraplegia Rating Scale between male and female patients as well as between patients with and without family history (P > 0.05, for all). Conclusion The onset age of pure HSP is variational and males are more common than females. The most common inheritance mode is autosomal dominant and most of the cases are characterized by impairment of the pyramidal tract of the lower limbs and occasionally bladder dysfunction and peripheral nerve damage. Gender and family history do not affect the clinical features. Clinical features, family history and spinal cord MRI will assist the correct diagnosis, and making a definite diagnosis needs genetic tests.

Key words: Spastic paraplegia, hereditary, Genes, Magnetic resonance imaging

摘要： 目的 研究单纯型遗传性痉挛性截瘫的临床特点和诊断策略，提高认识。方法 选择2006 年10 月-2013 年2 月门诊或住院诊断与治疗的单纯型遗传性痉挛性截瘫患者，分析其临床特点，并对患者进行痉挛性截瘫量表评价。结果 共纳入33 例患者，男性21 例、女性12 例，其中13 例（39.39%）有阳性家族史，11 例（11/13）为常染色体显性遗传。平均发病年龄（20.35 ± 15.55）岁，平均病程（12.77 ± 9.83）年。病程中均出现锥体束损害体征，表现为双侧下肢肌张力增高、腱反射亢进、病理征阳性，部分累及上肢。29 例呈典型剪刀步态，5 例合并弓形足，5 例出现胸髓萎缩，2 例肌电图检查提示合并周围神经损害。基因突变筛查发现，SPG4 基因第10 ~ 17 外显子区域大片段缺失突变（4/11）。男性及女性患者年龄、平均发病年龄、平均病程、痉挛性截瘫量表评分差异无统计学意义（均P > 0.05），有家族史和无家族史患者平均发病年龄、平均病程、痉挛性截瘫量表评分差异亦无统计学意义（均P > 0.05）。结论 单纯型遗传性痉挛性截瘫发病年龄差异较大，男性多于女性，多为常染色体显性遗传。临床表现以下肢锥体束损害为主，可合并膀胱功能损害、周围神经损害症状，性别和家族史不影响该病临床特征。结合临床表现、阳性家族史、脊柱MRI检查等可协助诊断，明确诊断需进行相关基因学检测。

关键词: 痉挛性截瘫, 遗传性, 基因, 磁共振成像