白质消融性白质脑病

白质消融性白质脑病(leukoencephalopathy with vanish-ing white matter,VWM)又称儿童共济失调伴中枢神经系统髓鞘化不良(childhood ataxia with central nervous system hypomyelination, CACH, OMIM 306896),是一种常染色体隐性遗传的白质脑病,是儿童遗传性白质脑病中常见的类型之一,其患病率尚缺乏统计.     

白质消融性白质脑病临床分析

目的分析白质消融性白质脑病的临床特点及诊断方法。方法对9例临床诊断为该病的患儿的临床及头颅影像学特点、实验室检查等进行分析,结合病例对该病进行综述介绍。结果（1）临床表现：9例中8例出现神经系统症状和体征,1例仅有MRI异常。发病时间为生后6个月-3岁;5例家族史阳性,病前智力运动发育多正常;多以运动症状起病,下肢为著。6例发病前或每遇病情加重前有呼吸道感染史,3例病前有轻微头部外伤史;到目前为止,有症状的7例呈进行性加重病程,其中4例同时有发作性加重现象。所有病例智力受损相对轻。7例头围正常,8例有上运动单元病变体征,4例有共济失调体征。3例双侧视神经萎缩。（2）头颅MRI：表现为双侧对称弥漫性深部白质长T1长T2信号,可累及皮层下白质,额、顶叶为主,Flair像为对称性白质高信号伴部分白质低信号甚至囊性变或大部分白质低信号仅存少量线状稍高信号,为此症特征性改变。（3）其他遗传性白质脑病相关酶学或生化检查均正常。结论以运动障碍起病、运动障碍重于智力障碍、神经影像学改变显著重于临床表现、MRI表现为双侧对称弥漫性深部白质长T1长T2病变伴早期出现白质消融征象是本症的临床特点,临床诊断还需除外其他遗传性及获得性脑白质病。找到相应基因的致病突变可最终确诊。     

白质消融性白质脑病1例临床特征与基因类型分析

目的探讨白质消融性白质脑病的临床特点及早期诊断。方法回顾分析1例白质消融性白质脑病患儿的临床资料,并复习相关文献。结果患儿,女,1岁4个月,发热后出现运动、智力急剧倒退。在发病1周内逐渐出现吞咽困难、构音障碍、不能行走及进入昏迷。头颅磁共振成像示白质异常,且弥漫对称,最后出现和脑脊液相似的信号。基因检测发现患儿EIF2B5基因存在2个错义突变,分别位于外显子3和7的C.407 GA(p.R136H)和C.944GA(p.R315H)杂合变异,国内外均未报道,为新发现的基因变异。结合国外临床诊断标准及基因分析结果确诊为白质消融性白质脑病。因无有效的治疗手段,仅抗感染及对症治疗后患儿进入昏迷。结论发现2个新的EIF2B5基因错义突变,基因分析有助明确诊断白质消融性白质脑病。     

白质消融性白质脑病2 例报告并文献复习

目的探讨白质消融性白质脑病(VWM)的临床表现及基因表型。方法回顾性分析经基因检测确诊的2例VWM患儿的临床资料,并复习相关文献。结果 2例患儿发病年龄分别为8个月、2岁,既往精神运动发育均正常;在急性发热后出现精神反应差,认知、运动功能进行性倒退;脑脊液检查未见异常;头颅磁共振提示两侧大脑半球脑白质对称性异常信号;基因检测1例为EIF2B5复合杂合变异;另1例EIF2B2复合杂合变异,其中c.911_913del缺失变异导致第305号氨基酸缺失(p.305del),属于新突变,短期内死亡。结论 VWM早期精神、运动发育基本正常,发热后出现进行性神经系统功能倒退,预后差。EIF2B突变可确诊。     

白质消融性白质脑病的研究现状及进展

白质消融性白质脑病(leukoencephalopathy with vanishing white matter, VWM)也称儿童共济失调伴中枢神经系统髓鞘化不良(childhood ataxia with central hypomylination, CACH),是近年来新认识的常染色体隐性遗传的白质脑病[1].1998年正式命名为"白质消融性白质脑病"后,才作为一种独立的疾病被人们所认识[2].     

白质消融性白质脑病患儿12例临床与遗传学研究

目的对临床诊断为白质消融性白质脑病(VWM)的中国患儿进行真核细胞翻译启动因子2Bα-ε(eIF2Bα-ε)的相应编码基因(EIF2B1～5)突变分析,以期提高儿科医生对该病的认识。方法选择临床诊断为VWM的患儿为研究对象,分析其临床特征;进行EIF2B1～5基因突变筛查;对新发现的EIF2B5基因突变,在HEK293细胞中进行突变蛋白表达水平分析。结果2006至2008年在北京大学第一医院儿科临床诊断VWM患儿12例,其中男8例,女4例。发病前智力、运动发育正常或轻度落后;起病年龄为1岁6个月至6岁8个月,均亚急性起病,起病症状多为运动功能障碍。随访至2009年6月,病程为9个月至7年。均为病情进展性加重病程,其中7例伴发作性病情加重。头颅MRI检查均提示对称性大脑白质液化特征。共发现EIF2B5,EIF2B3和EIF2B2的16种突变,其中包括9种新突变:7种错义突变为EIF2B5:c.185AT(p.D62V),c.1004GC(p.C335S),c.1126AG(p.N376D);EIF2B3:c.140GA(p.G47E),c.1037TC(p.I346T);EIF2B2:c.254TA(p.V85E),c.922GA(p.V308M);1种无义突变为EIF2B5:c.805CT(R269X);1种缺失突变为EIF2B5:c.1827-1838del(p.S610-D613del)。其中EIF2B3突变占所有突变的18.8%(3/16)。蛋白表达水平分析发现EIF2B5基因的p.R296X和p.S610-D613del突变导致eIF2Bε的蛋白表达水平显著降低。结论12例患儿均符合VWM早期儿童型诊断,发现了9种EIF2B1～5的新突变,提示中国VWM患儿具有独特突变谱。新发现的EIF2B5p.R296X和p.S610-D613del突变可导致蛋白功能严重受损。     

肾上腺性白质脑病1例报告

男,7岁。半年前因视物不清以视神经炎住院,嗣后又往某眼科研究所就诊均无好转。1992年1月29日患儿语言不清,流涎,吞咽困难,喝水发呛,先后出现右上下肢、左下肢瘫痪;20天后出现不全性运动性失语,时而强哭强笑。脑MRI提示肾上腺性白质脑病(H型),于3月2日再入院。体验:神清,面色苍白,表情淡漠,被动卧位。双目失明,眼底视神经萎缩,双侧瞳孔等大等园,对光反应迟钝,右侧轻     

中国早期儿童型白质消融性白质脑病患儿17例自然病程随访及其基因型-表型分析

目的 通过观察和分析17例中国早期儿童型白质消融性白质脑病(VWM)患儿的自然病程发展,了解其主要神经系统表型的进展特点,初步进行基因型-表型分析.方法 选择2006年9月-2010年10月北京大学第一医院临床诊断的17例VWM中国患儿为研究对象,提取其外周血白细胞DNA,PCR扩增致病基因真核细胞翻译启动因子2B(EIF2B1～5)的外显子及外显子与内含子交界区进行分子诊断.对其神经系统障碍的进展进行随访分析.结果 1.基本情况:17例患儿中男12例,女5例.13例起病前发育正常.2.起病特点:起病年龄平均2.7岁(0.4～6.4岁),70%(12/17例)为感染或头部外伤后急性起病,30%(5/17例)无诱因亚急性起病,均以运动障碍起病.3.病程特点:末次随访平均病程4.30 a(0.30～8.70 a),均呈进行性加重,3例死亡.64%(11/17例)病程中伴发作性加重.已获得独走技能的患儿最早于起病后0.17 a不能独走,发病2.00 a后均不能独走.发病4.50 a后患儿均丧失行走能力,最早丧失行走能力的年龄为起病后0.42 a,丧失行走能力的平均年龄为5.2岁(2.0～11.0岁),起病年龄越小,丧失行走能力的年龄越早.认知功能障碍进展缓慢.6例(35%)伴惊厥.重型患儿中女童明显少于男童.4.基因型-表型关系:重型患儿中eIF2Bγ突变者多于eIF2Bε突变者,相同基因型(eIF2Bγ:I346T)患儿表型存在明显差异.结论 早期儿童型VWM中国患儿运动功能退化进展最为突出,进展速度快.目前尚缺乏明确的基因型-表型相关性.     

巨脑性白质脑病伴皮层下囊肿一家系MLC1基因突变分析

目的通过对巨脑性白质脑病伴皮层下囊肿(MLC)一家系的分析,确定其MLC1基因的改变及遗传特征。方法收集先证者及其家系成员的临床资料,采用聚合酶链反应(PCR)和DNA直接测序方法进行MLC1基因突变检测,确定基因突变位点,明确MLC诊断。结果本家系先证者临床符合MLC诊断。测序结果发现两个基因位点改变c.218G>A(p.Gly73Glu)和IVS9-1G>C。患儿为复合杂合突变致病,其c.218G>A突变来自母亲,IVS9-1G>C突变来自父亲,其父母均为表型正常携带者。结论此家系中1例中国MLC患儿存在MLC1基因复合杂合突变,一个是错义突变,另一个是剪接位点突变。     

MRI of a family with leukoencephalypathy with vanishing white matter

Leukoencephalopathy with vanishing white matter (VWM) is a newly described entity with characteristic MRI features. We report the cranial MRI findings in three sisters with slowly progressive neurological deterioration. The MRI showed symmetrical diffuse abnormalities of cerebral white matter with hypointensity on FLAIR images. The diagnosis of leukoencephalopathy with VWM was made on the basis of genetic analysis.     

An unusual neuroimaging finding and response to immunotherapy in a child with genetically confirmed vanishing white matter disease

Background

We present an unusual neuroimaging finding in a young girl with genetically confirmed vanishing white matter disease and a possible response to immunotherapy.

Early reduction of total N-acetyl-aspartate-compounds in patients with classical vanishing white matter disease. A long-term follow-up MRS study

The neuropathology of vanishing white matter (VWM) disease is characterized by a loss of white matter (WM). Although recent histopathological studies suggest a primary glial dysfunction, the purpose of this work was to assess the extent of axonal involvement in VWM using long-term follow-up proton MR spectroscopy. White and gray matter of nine children with genetically proven VWM and late infancy/early childhood onset were investigated with short-echo time, single-voxel proton MR spectroscopy over up to 8 years starting as early as less than 2 years after the onset of symptoms (5 patients). Total N-acetyl-aspartate (-51% from normal control), creatine and phosphocreatine (-47%), and myo-inositol (-49%) were reduced in WM at early disease stages. Choline-containing compounds were less severely decreased (-31%). Follow-up investigations revealed progressive reduction of all metabolites in WM. In gray matter, no distinct changes were detected at early stages. Later total N-acetyl-aspartate decreased slightly (-22%). Assuming the metabolite alterations to primarily reflect changes in cellular composition, the observed pattern indicates early axonal involvement or loss as well as relatively enhanced turnover of myelin. These early stages are followed by a complete cellular loss in cerebral WM.     

Vanishing white matter disease in a child presenting with ataxia

Vanishing white matter disease is a recently described leukoencephalopathy that is characterized by chronic and episodic neurological deterioration. These episodes often follow periods of fever or minor head trauma. It frequently presents in childhood with problems of ataxia and tremor. Five genes have been identified for the disease, EIF2B1-5, which encode the five subunits of translation initiation factor eIF2B. Mutations in each of the genes may independently cause the disease. The defect in eIF2B results in abnormalities in translation and its regulation, leading to abnormalities in protein synthesis and its regulation. Magnetic resonance imaging of the brain reveals extensive cerebral white matter abnormalities with evidence of white matter rarefaction and cystic degeneration, which has been confirmed pathologically. We report the first confirmed Australasian patient.