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Disease Profile

Paroxysmal exertion-induced dyskinesia

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
<1 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Infancy

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ICD-10

G24.8

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

DYT18; PED; Paroxysmal exercise-induced dystonia;

Categories

Congenital and Genetic Diseases; Nervous System Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 98811

Definition
Paroxysmal exertion-induced dyskinesia (PED) is a form of paroxysmal dyskinesia (see this term), characterized by painless attacks of dystonia of the extremities triggered by prolonged physical activities.

Epidemiology
The prevalence is unknown but 20 sporadic cases and 9 families have been described to date.

Clinical description
The age of onset is usually in childhood, but may range from 1 to 30 years. PED is characterized by dyskinesias induced by prolonged exercise of 15-60 minutes of duration. The attacks last between 5 minutes and 2 hours and are typically restricted to the exercised limbs. The dystonic movements are usually bilateral and are aggravated by cold, psychological stress, fatigue and lack of sleep. The frequency of attacks varies between one per day to one per month. Brisk, deep tendon reflexes, developmental delay and intellectual disability (most frequently mild) may also be observed. In some familial forms, epilepsy or migraine can co-occur. PED can be associated with paroxysmal dystonic choreathetosis with episodic ataxia and spasticity, benign familial infantile seizures (BFIE), infantile convulsions and choreoathetosis (ICCA syndrome) or rolandic epilepsy paroxysmal exercise-induced dystonia writer's cramp (see these terms).

Etiology
The pathophysiology of PED is still unknown but some familial cases were found to be associated with mutations in the SLC2A1 (solute carrier family 2 (facilitated glucose transporter), member 1) gene (1p34.2). SLC2A1 encodes the glucose transporter GLUT1. All mutations in this gene responsible for PED have been found to affect the ability of GLUT1 to transport glucose. It has thus been proposed that an energy deficiency upon exertion caused by a reduced glucose transport rate is a cause of this paroxysmal movement disorder in SLC2A1 related cases.

Diagnostic methods
The diagnosis of PED relies on clinical examination and laboratory investigations showing hypoglycorrhachia and hypoglycemia. Electroencephalography (EEG) and brain imaging are normal. The diagnosis is confirmed by molecular genetic screening of SLC2A1 gene.

Differential diagnosis
The differential diagnosis includes paroxysmal kinesigenic dyskinesia (PKD), young adult-onset Parkinsonism and encephalopathy due to GLUT1 deficiency (see these terms).

Antenatal diagnosis
Prenatal diagnosis for pregnancies at increased risk of PED is possible by analysis of DNA extracted from fetal cells obtained by amniocentesis (usually performed at 15-18 weeks' gestation) or chorionic villus sampling (usually performed at 10-12 weeks' gestation). The disease-causing mutation of an affected family member must be identified in the family before prenatal testing can be performed.

Genetic counseling
Sporadic and familial cases with autosomal dominant mode of inheritance have been reported for PED. Genetic counseling should be offered to patients and families.

Management and treatment
There is no specific cure or treatment but avoiding precipitating events such as prolonged physical exercise may largely improve the symptoms. Moreover, a ketogenic diet for patients may prevent attacks and may lead to improvement of developmental delay in affected children.

Visit the Orphanet disease page for more resources.

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Choreoathetosis
0001266
Paroxysmal dyskinesia
0007166
30%-79% of people have these symptoms
Generalized non-motor (absence) seizure
Brief seizures with staring spells
0002121
Hyperactive deep tendon reflexes
0006801
Paresthesia
Pins and needles feeling
Tingling

[ more ]

0003401
Torsion dystonia
0001304
5%-29% of people have these symptoms
Aggressive behavior
Aggression
Aggressive behaviour
Aggressiveness

[ more ]

0000718
Ataxia
0001251
Irritability
Irritable
0000737
Specific learning disability
0001328
1%-4% of people have these symptoms
Intellectual disability, mild
Mental retardation, borderline-mild
Mild and nonprogressive mental retardation
Mild mental retardation

[ more ]

0001256
Lower limb spasticity
0002061

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Paroxysmal exertion-induced dyskinesia. Click on the link to view a sample search on this topic.