Paramyotonia congenita and hypokalemic periodic paralysis in a family with mutation p.R1448H in α-subunit type Ⅳ of voltage gated sodium channel gene
10.3760/cma.j.issn.1006-7876.2019.06.004
- VernacularTitle: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
- Author:
Xueqi PAN
1
;
Wei ZHANG
;
Xueli CHANG
;
Jing ZHANG
;
Huaxing MENG
;
Junhong GUO
Author Information
1. 山西医科大学第一临床医学院
- Keywords:
Hypokalemic periodic paralysis;
Paramyotonia congenita;
SCN4A gene
- From:
Chinese Journal of Neurology
2019;52(6):457-462
- CountryChina
- Language:Chinese
-
Abstract:
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.
