What is a syndrome?
A syndrome is a group of signs and symptoms that, added together, suggest a particular medical condition. In epilepsy, examples of these signs and symptoms would be things like the age at which seizures begin, the type of seizures, whether the child is male or female and whether they have physical or learning disabilities, or both. The results of an electroencephalogram (EEG) are also used to help identify epilepsy syndromes.
If you would like to know more about an epilepsy syndrome, please speak to your doctor. If you would like to know more about epilepsy in general, please contact Epilepsy Action.
Epilepsy with myoclonic absences
Epilepsy with myoclonic absences is a rare form of epilepsy. It happens more in boys than girls, and approximately 25 out of every 100 children (one quarter) will have another family member with a form of epilepsy. The underlying cause of this epilepsy syndrome is unknown. Myoclonic absences may be seen in children with brain abnormalities or with some genetic disorders.
The child loses awareness of their surroundings. How much their awareness is changed will vary from child to child. This is accompanied by severe rhythmical jerking of both upper limbs (possibly one arm more than the other). There can often be a stiffening of the upper arms resulting in the arms being raised upwards. Sometimes jerking of the muscles around the chin and mouth, but not the eyes, may also happen. The seizure usually lasts for eight to 60 seconds. Seizures are more common when the child is tired or has just woken up.
Other seizure types such as tonic-clonic, drop attacks and typical absence seizures can happen in about two-thirds of children. Almost half of all children with epilepsy with myoclonic absences have some degree of learning disability before the start of their seizures. Of the remainder, a further half will develop learning disabilities and behavioural problems after their seizures start.
A description of the seizure given by the child and any eyewitnesses can help with identifying the particular seizure type in this epilepsy syndrome. An EEG will be carried out. The doctor may try to provoke a seizure by getting the child to hyperventilate (over-breathe) for up to four minutes. Although this may feel unpleasant, it is important in order to correctly diagnose this syndrome. The doctor may want to order further tests, including a brain scan and a blood test, to look for genetic disorders.
Treatment is often difficult, as seizures may not respond to epilepsy medicines. Commonly used epilepsy medicines include sodium valproate (Epilim), ethosuximide (Zarontin) and lamotrigine (Lamictal). A combination of lamotrigine and sodium valproate, or ethosuximide and sodium valproate, is often more effective than a single drug. Another epilepsy medicine, clobazam (Frisium) may also be helpful.
Information about treatments for children can be found on the Medicines for Children website.
There may be research studies open that are relevant to this epilepsy syndrome. Your child’s doctor will be able to discuss this with you.
Epilepsy with myoclonic absences has a variable but often poor prognosis, with over half of all children continuing to have seizures into adulthood. Children whose seizures don’t respond well to treatment are at particular risk of developing other seizure types. There is some evidence that these children are also most at risk of developing learning and behavioural difficulties.
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Epilepsy Action would like to thank:
- Dr Richard Appleton, and Dr Rachel Kneen, consultant paediatric neurologists at Alder Hey Children’s Hospital, Liverpool, UK and
- Dr Stewart Macleod, consultant paediatric neurologist at Royal Hospital for Sick Children, Glasgow, UK.
They have kindly prepared the information on this page. It is based on their own research, experience and expertise.