hyperekplexia


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hy·per·ek·plex·i·a

(hī'pĕr-ek-plek'sē-ă), [MIM*149400]
A hereditary disorder in which there are pathologic startle responses, that is, protective reactions to unanticipated, potentially threatening, stimuli of any type, particularly auditory; the stimuli induce often widespread and violent sudden contractions of the head, neck, spinal, and sometimes, limb musculature, resulting in involuntary shouting, jerking, jumping, and falling; autosomal dominant and recessive inheritance forms, with the responsible gene localized to chromosome 5q; probably the result of lack of inhibitory neurotransmitters, glycine, or GABA.
[hyper- + G. ekplēxia, sudden shock, fr. ekplēssō, to startle]

hy·per·ek·plex·i·a

(hī'pĕr-ek-pleks'ē-ă)
A hereditary disorder in which there are pathologic startle responses, i.e., protective reactions to unanticipated, potentially threatening, stimuli of any type, particularly auditory; the stimuli induce often widespread and violent sudden contractions of the head, neck, spinal, and sometimes limb musculature, resulting in involuntary shouting, jerking, jumping, and falling; autosomal dominant and recessive inheritance forms, with the responsible gene localized to chromosome 5q; probably the result of lack of inhibitory neurotransmitters, glycine, or GABA.
Synonym(s): kok disease, startle disease.
[hyper- + G. ekplēxia, sudden shock, fr. ekplēssō, to startle]

hyperekplexia

, hyperexplexia (hī″pĕr-ĕk-plĕk'sē-ă) (-ĕks-) [Gr. hyper, over, above, excessive, + ekplexia, sudden shock]
Excessive startling in response to sound or physical contact. Extreme reflex reaction to neurological stimulation is often an autosomal (dominant or recessive) disorder. It may also occur in some degenerative neurological disorders (e.g., multiple sclerosis).
References in periodicals archive ?
Both Lesley and Allan" Both Lesley and Allan carry the faulty gene that crry the faulty gene that causes hyperekplexia, but fortunately their eldest son, Josh, seven, did not inherit the illness.
It's the worst night of the year for Andy Latham, 33, from Lincolnshire, who is believed to be Britain's only sufferer of hyperekplexia, or startle disease.
This condition is also known as 'stiff baby syndrome' or 'startle disease' Hyperekplexia can present in major and minor forms and is caused by a mutation in chromosome 5 which results in a defect in the [alpha]-1 subunit of the inhibitory glycine receptors in the caudal pontine reticular formation leading to neuronal hyperexcitability.
The name hyperekplexia was suggested by Suhren et al in 1966 when they described this syndrome in a Dutch family (2).
On further evaluation, a diagnosis of hyperekplexia was made and therapy was changed to oral clonazepam with a reduction in his symptoms, although he still showed an exaggerated startle reflex in response to minor stimuli.
When such a reflex is pathologically exaggerated, resulting in tonic spasms, it is termed hyperekplexia or "startle disease" (4).
She was born with a neurological condition, hyperekplexia, but doctors said it was not fatal.
Hyperekplexia is a brain condition which is believed can cause sudden infant death in babies but it is not believed to be fatal in adults.
A novel recessive hyperekplexia allele GLRA1 (S231R): genotyping by MALDI-TOF mass spectrometry and functional characterisation as a determinant of cellular glycine receptor trafficking.
The discovery came as the team, led by Professor Mark Rees, carried out complex research looking at genes thought to be responsible for the rare hereditary neurological disorder hyperekplexia.
Instead it will help parents and medical experts understand the increased risk of cot death if a child is diagnosed with hyperekplexia.
There is evidence that hyperekplexia, because of the muscle stiffness and breath-holding, can potentially cause Sids [sudden infant death syndrome].