成人型亚历山大病(附1例报告及文献复习)

Adult Alexander's Disease: One Case Report and Literature Review

目的提高对成人型亚历山大病的认识。方法报告1例成人型亚历山大病病例,回顾性分析患者的临床资料、实验室检查、影像学检查及基因检查结果,并结合复习相关文献进行讨论。结果患者为24岁青年男性,临床表现为反复头痛、夜间睡眠差、行走不稳、动作协调性差、尿失禁。无癫发作,记忆力无明显下降。头颅MRI示双侧侧脑室、第三脑室、中脑导水管、第四脑室周围、双侧岛叶皮质下及延髓的多发T2高信号征象,提示白质脱髓鞘病变并有胼胝体发育不全、小脑萎缩。基因检查示患者携带GFAP基因一个致病性的杂合变异,该突变导致编码蛋白GFAP(17q21/NM-002055. 4)第8外显子呈现c. 1246C> T错义突变。其父母基因检测未见基因突变,表明该突变为新生突变及致病性突变。结论亚历山大病是一种少见的白质脑病;其基因突变为新发变异,该突变导致编码蛋白GFAP杂合变异,基因缺陷是造成成人型亚历山大病的病因,基因检测及MRI影像学检查可明确诊断。

Aim To improve the understanding of adult Alexander’s disease. Methods The clinical data,laboratory examination,imaging examination and gene examination results of an adult Alexander patient were retrospectively analyzed,and the related literature for discussion was reviewed. Results The patient was a 24-year-old male. The clinical manifestations were repeated headaches,poor night sleep,unsteady walking,poor coordination,inability to run fast,urinary incontinence,no epileptic seizure,and no obvious decline in memory. Head MRI showed abnormal signals in bilateral ventricles,third ventricles,midbrain aqueduct,peripheral ventricles of the fourth ventricle,subcortex of bilateral insular cortex and medulla oblongata, the possibility of white matter demyelination, agenesis of corpus callosum, the cerebellum atrophy is considered. Genetic tests showed that the patient carried a pathogenic heterozygote variant of GFAP gene. This mutation led to the c. 1246 C > T missense mutation in the 8 th exon of the coding protein GFAP( 17 q21/nm-002055. 4). No mutation was found in the parent’s gene,indicating that the mutation was a new mutation and a pathogenic mutation. Conclusion Alexander ’s disease is a rare nonfamiliar white matter encephalopathy,the gene mutation is a new mutation,and the mutation leads to heterozygous mutation of the coding protein GFAP. The diagnosis can be confirmed by clinical genetic testing.