[2] The disease is named after Heinrich Unverricht, who first described it in 1891,[3][4] and Herman Bernhard Lundborg, who researched it in greater detail in 1901[5] and 1903.
The myoclonic jerks occur in the muscles of the arms and legs closest to the torso, and are triggered due to a variety of common external stimuli.
Eventually, people with Unverricht-Lundborg disease may develop ataxia, intention tremor, dysarthria, depression, and a slow, mild decline in intellectual functioning.
[2] Siblings of affected individuals who only have one recessive gene have been monitored and generally do not show the signs of ULD, though in some cases mild symptoms may be present.
[11] The researchers chose to investigate dopamine receptors because they are known to be a factor in myoclonus, which are a significant part of the symptoms of ULD.
This research has been performed on mice with the gene for producing cystatin B removed, to provide a similar set of symptoms to individuals with ULD.
It is hypothesized that this increase in excitability is what causes the myoclonic jerks and tonic-clonic seizures in patients with ULD.
Normally, after a seizure, the presence of cystatin B prevents the neurons from dying due to toxic levels of neurotransmitters.
[12] The only currently available method to diagnose Unverricht–Lundborg disease is a genetic test to check for the presence of the mutated cystatin B gene.
While electroencephalogram (EEG) is useful in identifying or diagnosing other forms of epilepsy, the location of seizures in ULD is currently known to be generalized across the entire brain.
However, with recent research linking ULD brain damage to the hippocampus,[12] the usefulness of EEG as a diagnostic tool may increase.
[citation needed] While there is no current cure to repair the mutated CSTB gene, several antiepileptic drugs are effective in reducing seizures and helping patients with ULD to manage the symptoms.
[citation needed] Valproic acid is the first line drug choice for reducing generalised seizures and myoclonus.
Due to the progressive nature of the disease, depression is prevalent,[8] but support of family and friends as well as proper treatment can help.
While early patients with ULD had a life expectancy of around 24 years,[8] there have recently been reported cases of individuals living to near-normal ages.
[citation needed] Many studies have been performed recently to investigate the cause, mechanism, and chemical basis of Unverricht–Lundborg disease.
A recent study has attempted to characterize the effects, if any, seen in mice that carry only one recessive CSTB gene (are heterozygous).