SCN4A基因p.R1448H突变致先天性副肌强直合并低钾性周期性麻痹一家系报道  

Paramyotonia congenita and hypokalemic periodic paralysis in a family with mutation p.R1448H in α-subunit type Ⅳ of voltage gated sodium channel gene

作　　者：潘学琪 张炜[2] 畅雪丽[2] 张晶[2] 孟华星[2] 郭军红[2] Pan Xueqi;Zhang Wei;Chang Xueli;Zhang Jing;Meng Huaxing;Guo Junhong(The First Clinical Medical College of Shanxi Medical University,Taiyuan 030001,China;Department of Neurology,the First Hospital of Shanxi Medical University,Taiyuan 030001,China)

机构地区：[1]山西医科大学第一临床医学院,太原030001 [2]山西医科大学第一医院神经内科,太原030001

出　　处：《中华神经科杂志》2019年第6期457-462,共6页Chinese Journal of Neurology

摘　　要：目的通过报道先天性副肌强直合并低钾性周期性麻痹一家系临床、电生理、病理及基因突变特点,旨在提高临床对离子通道病的认识,为临床诊断提供参考。方法收集2017年10月就诊于山西医科大学第一医院的先天性副肌强直合并低钾性周期性麻痹一家系中部分患者的临床资料、电生理检查、骨骼肌活体组织病理检查结果,并对部分患者进行基因检测。结果先证者表现为肌强直伴发作性肌无力,家系中不同患者的表现各异,有单纯表现为肌强直或肌无力,有表现为发作性肌无力伴肌强直。先证者针极肌电图可见肌强直电位,冷环境(11 ℃)长程运动试验示运动后40 min复合肌肉运动电位波幅下降36%,家系基因检测发现SCN4A基因p.R1448H突变。结论本研究中先证者具有低钾性周期性麻痹及先天性副肌强直的表现。家系临床表现提示有表型异质性。冷环境(11 ℃)长程运动试验证实先证者为低钾性周期性麻痹合并先天性副肌强直。家系基因检测提示SCN4A基因p.R1448H突变是低钾性周期性麻痹合并先天性副肌强直的致病基因突变位点。Objective Through description of the clinical, electrophysiological, pathological and gene sequencing characteristics of a family diagnosed as paramyotonia congenita and hypokalemic periodic paralysis to broaden the understanding of skeletal muscle channel disease and provide the reference for clinical diagnosis. Methods The clinical manifestation, electromyography, muscle pathology and gene sequencing of a family diagnosed as paramyotonia congenita and hypokalemic periodic paralysis in the First Hospital of Shanxi Medical University in October 2017 were collected. Results The proband represented myotonia and episodic muscle weakness, and the manifestations of different patients of the family were varied, including myotonia, episodic muscle weakness or myotonia and episodic muscle weakness. The electromyography of the proband showed myotonic potential, and the compound muscle action potential decreased by 36% in 40 minutes after exercise in the long exercise test in cold environment (11 ℃). The gene sequencing showed α-subunit type Ⅳ of voltage gated sodium channel (SCN4A) gene p.R1448H mutation. Conclusions The proband presented with paramyotonia congenita and hypokalemic periodic paralysis. Family clinical manifestations suggested phenotypic heterogeneity. The long exercise text in cold environment (11 ℃) confirmed the diagnosis of the proband as paramyotonia congenita and hypokalemic periodic paralysis. Family gene sequencing showed that the mutation of p.R1448H in SCN4A gene was the pathogenic gene mutation site of paramyotonia congenita and hypokalemic periodic paralysis.

关 键 词：低钾性周期性麻痹 先天性副肌强直 SCN4A基因 

分 类 号：R746[医药卫生—神经病学与精神病学]