正常血钾型周期麻痹性副肌强直一家系的临床及基因突变特征  

Characteristics of Clinical and Gene Mutation of a Family with Normal Blood Potassium and Periodic Paralysis Paramyotonia

作　　者：许丹阳 杨晓辉 宋亚菲 杜敢琴[1] 姜宏卫[1] 彭慧芳 XU Danyang;YANG Xiaohui;SONG Yafei;DU Ganqin;JIANG Hongwei;PENG Huifang(Neurology Department,the First Affiliated Hospital of Henan University of Science and Technology,Luoyang 471003,China)

机构地区：[1]河南科技大学第一附属医院神经内科,河南洛阳471003

出　　处：《河南医学研究》2021年第33期6160-6164,共5页Henan Medical Research

基　　金：河南省中国科学院科技成果转移转化项目(2018105)。

摘　　要：目的报道伴正常血钾的周期麻痹性副肌强直(PPP)一家系的临床及基因突变特点。方法对一PPP家系的3代成员进行问诊和体格检查,收集患者的病史、临床特点。检查先证者发作期的电解质、血糖、甲状腺功能、肌电图、心电图,并对先证者、其他患者和先证者母亲(未患病)进行基因检测。结果该家系3代18名成员中有6名发病,男女均有累及,其中4名患者完成所有检查。家系中患者多于幼年起病,冬夏均有发作,表现为肌强直伴肌无力,或单纯肌无力、肌强直。运动后休息、饥饿、劳累、受凉等易诱发肌无力,以下肢多见;冷刺激诱发肌强直,受累肌肉主要分布于面、颈部。随年龄增长,发作症状减轻,频率减少。先证者症状重时全身无力,翻身起床困难,需要卧床3~4 d,症状完全缓解需1个月左右,发作期肌酸激酶1 182 U·L^(-1),2次查血清钾正常。本家系4名成员(先证者及先证者奶奶、父亲、叔叔)基因检测均发现SCN4A基因p.T704M突变,先证者母亲未发现该基因突变。结论本家系符合常染色体显性遗传,临床表型存在异质性,具有周期性麻痹和副肌强直的特征,发作时血清钾正常;SCN4A基因p.T704M突变是PPP的致病基因突变位点。Objective To report the characteristics of clinical and gene mutation of a family with normal blood potassium and periodic paralysis paramyotonia(PPP).Methods Three generations members of a PPP family were interviewed and physical examined,and the patient’s medical history and clinical characteristics were collected.The electrolyte,blood glucose,thyroid function,electromyography,electrocardiogram of the proband during the attack period were checked,and gene detection of the proband,other patients and the proband’s mother(not sick)were carried out.Results Six of the 18 members of the 3 generations of the family had the onset of disease,with no gender difference,and four of the patients completed all tests.The onset of symptoms in all patients started at early childhood,with attacks in winter and summer,manifested as muscle rigidity with muscle weakness,or simple muscle weakness and muscle rigidity.Muscle weakness was induced by post-exercise,hunger,fatigue and cold,which was more common in lower limbs.Cold stimulation induces muscle rigidity,and the affected muscles were mainly distributed in the face and neck.The onset symptoms and frequency decreased with age.The proband was weak when the symptoms were severe,and it was difficult to turn over and get up.The proband needed to stay in bed for 3-4 days.It taked about 1 month for the symptoms to be completely relieved,and creatine kinase was 1182 U·L^(-1)during the attack,and serum potassium was normal twice.Genetic testing of 4 members of the family(the proband,grandmother,father and uncle of the proband)showed a p.T704M mutation in the SCN4A gene,the mutation was not found in the mother of the proband.Conclusion This family accords with autosomal dominant inheritance,with heterogeneous clinical phenotype,with the characteristics of periodic paralysis and paramyotonia,and the serum potassium is normal at the onset.The p.T704M mutation in the SCN4A gene is the pathogenic gene mutation site of PPP.

关 键 词：周期麻痹性副肌强直 SCN4A基因 离子通道病 

分 类 号：R746.9[医药卫生—神经病学与精神病学]