It’s estimated that fewer than 1,000 people in the U.S. have hereditary hyperekplexia.
This article explores symptoms, causes, and diagnosis.
It also discusses treatment options as well as help to cope with hyperekplexia.
Nusha Ashjaee
What Is Hyperekplexia?
Hyperekplexia (HPX) is a rare genetic disorder that affects both males and females.
It is most often diagnosed at birth.
In some people, onset may be delayed until adolescence or adulthood.
The exact prevalence of hereditary hyperekplexia is unknown.
Infants show increased muscle tone, also called hypertonia.
Some infants may stop breathing during the episode of rigidity, which can potentially lead to a life-threatening situation.
Furthermore, periods of rigidity may cause some individuals to fall without a loss of consciousness.
People with HPX may demonstrate gait abnormalities, overactive reflexes, and other signs and symptoms too.
How Do I Know if I Have Hyperekplexia?
The overall severity of the symptoms of hyperekplexia can vary widely among individuals.
The most characteristic symptom of HPX is an exaggerated startle reaction following an abrupt stimulus.
Other symptoms that may accompany HPX include:
What Causes Hyperekplexia?
Other potential causes of HPX include an autosomal recessive pattern or a new mutation in the gene.
With new mutations, the genetic variant spontaneously arises in the early stages of an individual’s development.
How Is Hyperekplexia Diagnosed?
An initial diagnosis of HPX may be based on the clinical presentation of the condition.
Genetic testing is an option to solidify a diagnosis and help find the cause.
Treating Hyperekplexia
Currently, there is no cure for the disorder.
For many people, HPX is curable in that the symptoms start to recede by age 1.
However, this isnt the case for everyone.
They may also experience overstimulation in crowds or places with loud noises.
Finding support from others who are going through similar experiences as you and your family members can be helpful.
For online HPX support forums, visitThe Hyperekplexia Societyon Facebook.
Another way to cope and find support is to connect with people with related disorders and similar symptoms.
Those conditions include epilepsy, generalized anxiety, and tic disorders (likeTourette syndrome).
Adults and children may be affected by HPX but it is most often diagnosed in infants.
Diagnosis can be made using genetic tests, EEG, EMG, and other testing.
Genetic and Rare Diseases Information Center.Hereditary hyperekplexia.
National Organization for Rare Disorders.Hyperekplexia.
Lim TT, Por CY, Beh YY, et al.Treatment of startle and related disorders.Clin Park Relat Disord.
2023 Sep 21;9:100218. doi:10.1016/j.prdoa.2023.100218
