Presentation
Patients with ATS typically present with the triad of periodic paralysis, cardiac arrhythmias, and developmental dysmorphisms. Although penetrance of ATS is high, disease expression and severity are remarkably variable. [ncbi.nlm.nih.gov]
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment. [orpha.net]
Cardiovascular
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Palpitations
The irregular heartbeats can lead to discomfort, such as the feeling that the heart is skipping beats (palpitations). Uncommonly, the irregular heartbeats can cause fainting (syncope), and even more rarely, sudden death. [ghr.nlm.nih.gov]
This, as in other forms of long QT syndrome, can lead to abnormal heart rhythms such as ventricular ectopy or ventricular tachycardia causing palpitations. [en.wikipedia.org]
All seven patients reported episodes of palpitations, while three of them associated it with presyncope or syncope (42.8%). Two subjects (28.5%) had a history of periodic paralysis. [innovationsincrm.com]
Palpitations, Syncope, or Cardiac Arrest Syncopal episodes are often interpreted as a neurologic problem rather than arrhythmia. Physical examination and ECG should be part of the evaluation of syncope. [ncbi.nlm.nih.gov]
Musculoskeletal
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Small Hand
hands and feet, and at least two of the following: Low-set ears Widely spaced eyes Small lower jaw (mandible) Fifth-digit clinodactyly (curved pinky finger) Syndactyly or 2. [rarediseases.info.nih.gov]
Additional findings include small hands and feet, loose joints, and abnormal sideways curvature of the spine (scoliosis). [rarediseases.org]
Novel findings include small hands and feet ( Note: Isolated reports of renal anomalies include unilateral hypoplastic kidney [ Andelfinger et al 2002 ] and renal tubular defect [ Davies et al 2005 ]. [ncbi.nlm.nih.gov]
The clinical diagnosis of ATS was performed by the presence of at least two of the following criteria: 1) familial periodic paralysis; 2) characteristic facies, dental abnormalities, or small hands/feet, and at least two of low-set ears, widely spaced [innovationsincrm.com]
Presence of 2 of the following 3 criteria: ‐ Periodic paralysis ‐ Symptomatic cardiac arrhythmias or ECG evidence of enlarged U‐waves, ventricular ectopy or a prolonged QTc or QUc interval ‐ Characteristic facies, dental anomalies, small hands and feet [doi.org]
Workup
Clinical Testing and Workup Because potassium levels may be reduced during an episode of periodic paralysis, a blood test to determine the serum potassium levels during an episode can be helpful in diagnosing the disorder in some cases. [rarediseases.org]
Cardiac evaluations using serial ECGs with measurements of the QTc interval are essential and should be performed on all patients undergoing workup for periodic paralysis. 23, 24, 25 References 1. [hkpp.org]
[…] more practical approach is calculation of the urine potassium-to-creatinine ratio from a spot urine specimen; a ratio greater than 1.5 mEq per mmol (13 mEq per g) is indicative of renal potassium wasting. 18 If no cause is identified with the initial workup [aafp.org]
T Wave
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Prominent U Wave
U-waves on ECG recording ( Figure 1 ). [innovationsincrm.com]
ECG was notable for prominent U waves, with sinus rhythm and a normal QT interval. Genetic screening identified a heterozygous mutation in the KCNJ2 gene. The patient returned during an attack for nerve conduction and needle EMG studies. [neurologytimes.com]
U wave; (3) at least two of the following dysmorphic features: low-set ears, wide-set eyes, a small mandible, fifth-digit clinodactyly, and syndactyly; and (4) a family member with confirmed Andersen–Tawil syndrome.Genetic testing can be used to identify [en.wikipedia.org]
U wave or prolonged QTc. [ncbi.nlm.nih.gov]
An electrocardiogram or EKG records the heart’s electrical impulses and may reveal abnormal electrical patterns or activity commonly associated with Andersen-Tawil syndrome including prominent U waves, prolonged QU intervals, prolonged QT intervals, premature [rarediseases.org]
Treatment
Standard Therapies Treatment The treatment of Andersen-Tawil syndrome is directed toward the specific symptoms that are apparent in each individual. Treatment may require the coordinated efforts of a team of specialists. [rarediseases.org]
Management and treatment Treatment depends on the individual and their reaction to potassium. Patients with severe arrhythmias may require a pacemaker. The documents contained in this web site are presented for information purposes only. [orpha.net]
NHLBI is part of the National Institutes of Health and supports research, training, and education for the prevention and treatment of heart, lung, and blood diseases. [rarediseases.info.nih.gov]
Prognosis
Diagnosis - Andersen Tawil syndrome Prognosis - Andersen Tawil syndrome Not supplied. Treatment - Andersen Tawil syndrome Resources - Andersen Tawil syndrome [checkorphan.org]
Parents should talk to their children’s physician and medical team about their specific case, associated symptoms and overall prognosis. [rarediseases.org]
However, in general, the prognosis is good. The optimal pharmacological therapy has to be identified. Beta-blockers, flecainide, and possibly other sodium-channel blockers and calcium-channel antagonists are good candidates. [academic.oup.com]
Electrical diseases of the heart are heritable arrhythmogenic clinical entities that may share common clinical and genetic features, yet may be distinctly different in their genesis, prognosis, and management. [worldcat.org]
Prognosis mainly depends on management of cardiac arrhythmia. Though muscle weakness is disabling, patients usually remain ambulatory throughout life. [japi.org]
Etiology
Summary Etiology Mutations in KCNJ2, which encodes the alpha subunit of the potassium channel Kir2.1, account for approximately 60% of cases. [orpha.net]
Isser, Sandeep Bansal, Anandaraja Subramanian, Bidirectional ventricular tachycardia of unusual etiology, Indian Pacing and Electrophysiology Journal, 2015, 15, 6, 296 CrossRef 19 Stephen C. [onlinelibrary.wiley.com]
This concept has proven valuable for classifying disorders and understanding their etiology. In the case of muscle channelopathies, it has been especially helpful in the understanding of a group of rare disorders that, on the surface, are different. [journals.lww.com]
Epidemiology
Introduction to Part Two: Celebrating the Challenge of Cardiac Arrhythmias -- Congenital Long QT Syndrome -- Brugada Syndrome: Clinical and Genetic Aspects -- Brugada Syndrome: Cellular Mechanisms and Approaches to Therapy -- Early Repolarization Syndrome: Epidemiology [worldcat.org]
Home, Search, Index, Links, Pathology, Molecules, Syndromes, Muscle, NMJ, Nerve, Spinal, Ataxia, Antibody & Biopsy, Patient Info EPISODIC MUSCLE WEAKNESS Hypokalemic Periodic Paralysis Hypokalemic periodic paralysis, Hereditary: General features Epidemiology [neuromuscular.wustl.edu]
rare grp of disorders - mostly inherited as autosomal dominant traits Hypokalaemic periodic paralysis Aetiology & epidemiology - 1/3 cases sporadic - remainder predominantly inherited but in young men, particularly Latin Americans & Orientals may occur [aic.cuhk.edu.hk]
Relevant External Links for KCNJ2 Genetic Association Database (GAD) KCNJ2 Human Genome Epidemiology (HuGE) Navigator KCNJ2 Atlas of Genetics and Cytogenetics in Oncology and Haematology: KCNJ2 No data available for Genatlas for KCNJ2 Gene Genetic and [genecards.org]
Depending on the nature of the disease, the treatment may consist of thyrostatics (drugs that reduce production of thyroid hormone), radioiodine, or occasionally thyroid surgery. [1] [2] Epidemiology [ edit ] TPP occurs predominantly in males of Chinese [en.wikipedia.org]
Pathophysiology
[…] mostly inherited as autosomal dominant traits Hypokalaemic periodic paralysis Aetiology & epidemiology - 1/3 cases sporadic - remainder predominantly inherited but in young men, particularly Latin Americans & Orientals may occur in association with TTX Pathophysiology [aic.cuhk.edu.hk]
Brenner/Rector remains the go-to resource for practicing and training nephrologists and internists who wish to master basic science, pathophysiology, and clinical best practices. [books.google.com]
Kass, Molecular Pathophysiology of Congenital Long QT Syndrome, Physiological Reviews, 97, 1, (89), (2017). [doi.org]
This article reviews the epidemiology, etiology, pathophysiology, clinical manifestations, laboratory findings, differential diagnosis, and management of TPP. [enotes.tripod.com]
[…] periodic paralysis 1 (TTPP1), Susceptibility Congenital myopathy, Recessive or Dominant Also: Myotonic dystrophy (DM1) Alternative splicing of CACNA1S exon 29 is repressed Correlates with: Increased channel conductance & voltage sensitivity CACNA1S channel Pathophysiology [neuromuscular.wustl.edu]
Prevention
Many mutations prevent a molecule called PIP2 from binding to the channels and effectively regulating their activity. [en.wikipedia.org]
Prevention - Andersen Tawil syndrome Not supplied. Diagnosis - Andersen Tawil syndrome Prognosis - Andersen Tawil syndrome Not supplied. Treatment - Andersen Tawil syndrome Resources - Andersen Tawil syndrome [checkorphan.org]
Prevention of secondary complications : Cautious use of antiarrhythmic drugs (particularly class I drugs) that may paradoxically exacerbate the neuromuscular symptoms. [ncbi.nlm.nih.gov]
NHLBI is part of the National Institutes of Health and supports research, training, and education for the prevention and treatment of heart, lung, and blood diseases. [rarediseases.info.nih.gov]