1.Two Families of Andersen's Syndrome with Cardiac Arrhythmia, Periodic Paralysis, and KCNJ2 Gene Mutations.
Bum Chun SUH ; Byung Ok CHOI ; Ki Wha CHUNG ; Seung Min KIM ; Yeon Kyung JUNG ; Sang Beom KIM ; Il Nam SUNWOO
Journal of the Korean Neurological Association 2006;24(3):265-269
Andersen's syndrome is a rare autosomal dominant disorder characterized by periodic paralysis, dysmorphic features and cardiac arrhythmias. This syndrome is known to be a type of potassium channelopathies with a mutation in the KCNJ2 (Kir2.1) gene. Here, we present two families with genetically confirmed Andersen's syndrome through clinical and electrophysiological findings. They showed all features of the triad, and one of them had a novel mutation c.307G>A (Met307Ile).
Arrhythmias, Cardiac*
;
Channelopathies
;
Exercise Test
;
Humans
;
Paralysis*
;
Potassium
2.Congenital insensitivity to pain with anhidrosis: A case report and literature review.
Yanying CHEN ; Caixia LONG ; Lan LUO
Journal of Central South University(Medical Sciences) 2019;44(10):1203-1208
To analyze the clinical manifestations and gene mutations in children with congenital insensitivity to pain with anhidrosis (CIPA), and review related literature. An infant diagnosed with congenital insensitivity to pain with anhidrosis was reported. The main clinical manifestations of the infant were painless, no sweat, and repeated fever. Peripheral blood of the infant and his parents was collected, and candidate variants were confirmed by Sanger sequencing. The results of molecular genetic analysis showed that there were compound heterozygous mutations (c.36G>A, c.851-33T>A) of neurotrophic tyrosine kinase receptor type 1 (NTRK1) in the infant. c.36G>A and c.851-33T>A were inherited from his father and mother, respectively. c.851-33T>A is a previously reported mutation, c.36G>A is an unreported mutation, which can lead to the tryptophan changing into a stop codon. According to the American College of Medical Genetics and Genomics (ACMG) variant interpretation guidelines, the mutation is interpreted as pathogenic, and the biological hazard is potentially harmful. Congenital insensitivity to pain with anhidrosis is a rare inherited disorder. Genetic molecular genetic analysis is helpful to diagnose and discover new gene mutations.
Channelopathies
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Humans
;
Infant
;
Mutation
;
Pain Insensitivity, Congenital
;
Receptor, trkA
3.Hyperkalemic Paralysis with Unexplained Causes: A Case Report.
Hyeong Do CHO ; Joo Hark YI ; Young Hoon KIM ; Sang Woong HAN ; Ho Jung KIM
Korean Journal of Nephrology 2007;26(3):348-352
Hyperkalemic paralysis can be either a rare hereditary form due to channelopathies or common secondary ones related to various medications interfering potassium homeostasis upon underlying renal impairment. We hereby describe a 36-yr-old woman presented with the first episode of sudden hyperkalemic paralysis due to severe hyperkalemia, 8.6 mEq/L, but which resolved quickly to the normalization of serum potassium level by the conventional remedies, including calcium gluconate, insulin and glucose, and potassium-binding resin for severe hyperkalemia over 10 hours and remained normokalemic without any medications or dialysis for the next 10 days in hospital. The discernible history of medications or potassium-rich food intakes was denied on repeated interrogation. Other diagnostic work-ups to investigate its etiologies responsible for this acute hyperkalemic paralysis including neurological examination, serial biochemical data, and endocrinologic diagnostic work-ups for underlying causes failed, but only revealed only a transient hyperkalemic episode with appropriate response of renal potassium excretion. Therefore, we report a puzzling case of hyperkalemia with unexplained causes in a young woman, though the evidences are in favor of acute intracellular potassium shift based on the short duration of reversible hyperkalemia with intact response of increased renal potassium excretion.
Calcium Gluconate
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Channelopathies
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Dialysis
;
Female
;
Glucose
;
Homeostasis
;
Humans
;
Hyperkalemia
;
Insulin
;
Neurologic Examination
;
Paralysis*
;
Potassium
4.Whole-Body Muscle MRI in Patients with Hyperkalemic Periodic Paralysis Carrying the SCN4A Mutation T704M: Evidence for Chronic Progressive Myopathy with Selective Muscle Involvement.
Young Han LEE ; Hyung Soo LEE ; Hyo Eun LEE ; Seok HAHN ; Tai Seung NAM ; Ha Young SHIN ; Young Chul CHOI ; Seung Min KIM
Journal of Clinical Neurology 2015;11(4):331-338
BACKGROUND AND PURPOSE: Hyperkalemic periodic paralysis (hyperKPP) is a muscle sodium-ion channelopathy characterized by recurrent paralytic attacks. A proportion of affected individuals develop fixed or chronic progressive weakness that results in significant disability. However, little is known about the pathology of hyperKPP-induced fixed weakness, including the pattern of muscle involvement. The aim of this study was to characterize the patterns of muscle involvement in hyperKPP by whole-body magnetic resonance imaging (MRI). METHODS: We performed whole-body muscle MRI in seven hyperKPP patients carrying the T704M mutation in the SCN4A skeletal sodium-channel gene. Muscle fat infiltration, suggestive of chronic progressive myopathy, was analyzed qualitatively using a grading system and was quantified by the two-point Dixon technique. RESULTS: Whole-body muscle MRI analysis revealed muscle atrophy and fatty infiltration in hyperKPP patients, especially in older individuals. Muscle involvement followed a selective pattern, primarily affecting the posterior compartment of the lower leg and anterior thigh muscles. The muscle fat fraction increased with patient age in the anterior thigh (r=0.669, p=0.009), in the deep posterior compartment of the lower leg (r=0.617, p=0.019), and in the superficial posterior compartment of the lower leg (r=0.777, p=0.001). CONCLUSIONS: Our whole-body muscle MRI findings provide evidence for chronic progressive myopathy in hyperKPP patients. The reported data suggest that a selective pattern of muscle involvement-affecting the posterior compartment of the lower leg and the anterior thigh-is characteristic of chronic progressive myopathy in hyperKPP.
Channelopathies
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Humans
;
Leg
;
Magnetic Resonance Imaging*
;
Muscles
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Muscular Atrophy
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Muscular Diseases*
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Paralysis, Hyperkalemic Periodic*
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Pathology
;
Thigh
5.Ion channelopathies and inherited arrhythmia.
Journal of Zhejiang University. Medical sciences 2010;39(1):97-102
Ion channelopathies are the mainly etiopathogenisis of inherited arrhythmia. Those arrhythmia syndromes are commonly caused by ion channel gene mutation, which can be classified as sodium,potassium and calcium ion channel mutation.Changes in the genes encoding for cardiac ion channel subunits produce modification in the function of the channels, and cause the dysfunctions of cardiac electrical activity; and the clinical manifestation is malignant arrhythmia.
Animals
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Arrhythmias, Cardiac
;
genetics
;
physiopathology
;
Channelopathies
;
genetics
;
physiopathology
;
Humans
;
Ion Channels
;
genetics
;
physiology
;
Mutation
6.Analysis of SCN4A gene variation in a Chinese pedigree affected with skeletal muscle sodium channelopathies.
Yan LU ; Xiaohui YANG ; Xiuxia WANG ; Ping XUE ; Jinhong ZHANG ; Yuejing LI
Chinese Journal of Medical Genetics 2019;36(8):809-812
OBJECTIVE:
To explore the clinical features of a Chinese pedigree affected with skeletal muscle sodium channelopathies due to variation of SCN4A gene.
METHODS:
Potential variation of the 24 exons of the SCN4A gene was screened using PCR and Sanger sequencing.
RESULTS:
Four family members were affected with the disease in an autosomal dominant inheritance pattern. Three patients had normekalemic periodic paralysis, while 1 showed paramyotonia congenita. Genetic analysis detected a missense variation c.2078T>C (p.Ile693Thr) in exon 13 of the SCN4A gene in the proband and other 3 affected relatives.
CONCLUSION
Normokalemic periodic paralysis and paramyotonia congenita can occur in different family members with skeletal muscle sodium channelopathies due to c.2078T>C(p.Ile693Thr) variation of SCN4A gene.
Channelopathies
;
genetics
;
Humans
;
Muscle, Skeletal
;
physiopathology
;
Mutation
;
NAV1.4 Voltage-Gated Sodium Channel
;
genetics
;
Pedigree
7.Research Progress and Forensic Application of Postmortem Genetic Testing in Hereditary Cardiac Diseases.
Yi-Ming DONG ; Chen-Teng YANG ; Guo-Zhong ZHANG ; Bin CONG
Journal of Forensic Medicine 2022;38(3):374-384
Hereditary cardiac disease accounts for a large proportion of sudden cardiac death (SCD) in young adults. Hereditary cardiac disease can be divided into hereditary structural heart disease and channelopathies. Hereditary structural heart disease mainly includes hereditary cardiomyopathy, which results in arhythmia, heart failure and SCD. The autopsy and histopathological examinations of SCD caused by channelopathies lack characteristic morphological manifestations. Therefore, how to determine the cause of death in the process of examination has become one of the urgent problems to be solved in forensic identification. Based on the review of recent domestic and foreign research results on channelopathies and hereditary cardiomyopathy, this paper systematically reviews the pathogenesis and molecular genetics of channelopathies and hereditary cardiomyopathy, and discusses the application of postmortem genetic testing in forensic identification, to provide reference for forensic pathology research and identification of SCD.
Autopsy/methods*
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Channelopathies/genetics*
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Death, Sudden, Cardiac/pathology*
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Genetic Testing
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Heart Diseases/genetics*
;
Humans
;
Young Adult
8.Management of Patients with Long QT Syndrome.
Korean Circulation Journal 2016;46(6):747-752
Long QT syndrome (LQTS) is a rare cardiac channelopathy associated with syncope and sudden death due to torsades de pointes and ventricular fibrillation. Syncope and sudden death are frequently associated with physical and emotional stress. Management of patients with LQTS consists of life-style modification, β-blockers, left cardiac sympathetic denervation (LCSD), and implantable cardioverter-defibrillator (ICD) implantation. Prohibition of competitive exercise and avoidance of QT-prolonging drugs are important issues in life-style modification. Although β-blockers are the primary treatment modality for patients with LQTS, these drugs are not completely effective in some patients. Lifelong ICD implantation in young and active patients is associated with significant complications. LCSD is a relatively simple and highly effective surgical procedure. However, LCSD is rarely used.
Channelopathies
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Death, Sudden
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Defibrillators, Implantable
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Humans
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Long QT Syndrome*
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Stress, Psychological
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Sympathectomy
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Syncope
;
Torsades de Pointes
;
Ventricular Fibrillation
9.An atypical phenotype of hypokalemic periodic paralysis caused by a mutation in the sodium channel gene SCN4A.
Korean Journal of Pediatrics 2010;53(10):909-912
Familial hypokalemic periodic paralysis is an autosomal-dominant channelopathy characterized by episodic muscle weakness with hypokalemia. The respiratory and cardiac muscles typically remain unaffected, but we report an atypical case of a family with hypokalemic periodic paralysis in which the affected members presented with frequent respiratory insufficiency during severe attacks. Molecular analysis revealed a heterozygous c.664 C>T transition in the sodium channel gene SCN4A, leading to an Arg222Trp mutation in the channel protein. The patients described here presented unusual clinical characteristics that included a severe respiratory phenotype, an incomplete penetrance in female carriers, and a different response to medications.
Channelopathies
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Female
;
Humans
;
Hypokalemia
;
Hypokalemic Periodic Paralysis
;
Muscle Weakness
;
Myocardium
;
Penetrance
;
Phenotype
;
Respiratory Insufficiency
;
Sodium
;
Sodium Channels
10.Potassium Channelopathies and Gastrointestinal Ulceration.
Jaeyong HAN ; Seung Hun LEE ; Gerhard GIEBISCH ; Tong WANG
Gut and Liver 2016;10(6):881-889
Potassium channels and transporters maintain potassium homeostasis and play significant roles in several different biological actions via potassium ion regulation. In previous decades, the key revelations that potassium channels and transporters are involved in the production of gastric acid and the regulation of secretion in the stomach have been recognized. Drugs used to treat peptic ulceration are often potassium transporter inhibitors. It has also been reported that potassium channels are involved in ulcerative colitis. Direct toxicity to the intestines from nonsteroidal anti-inflammatory drugs has been associated with altered potassium channel activities. Several reports have indicated that the long-term use of the antianginal drug Nicorandil, an adenosine triphosphate-sensitive potassium channel opener, increases the chances of ulceration and perforation from the oral to anal regions throughout the gastrointestinal (GI) tract. Several of these drug features provide further insights into the role of potassium channels in the occurrence of ulceration in the GI tract. The purpose of this review is to investigate whether potassium channelopathies are involved in the mechanisms responsible for ulceration that occurs throughout the GI tract.
Adenosine
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Channelopathies*
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Colitis, Ulcerative
;
Gastric Acid
;
Gastrointestinal Tract
;
Homeostasis
;
Intestines
;
Nicorandil
;
Peptic Ulcer
;
Potassium Channels
;
Potassium*
;
Stomach
;
Ulcer*