Doose Syndrome EEG

The EEG may initially be normal, but most have abnormal EEGs that show frequent generalized spike-wave activity at times in brief bursts of 2 to 5 Hz.

What is myoclonic atonic epilepsy (Doose Syndrome)?

Myoclonic atonic epilepsy (MAE), typically known as Doose Syndrome, was first described by Dr. Herman Doose from Germany in 1970. It is an uncommon childhood epilepsy syndrome that accounts for 1 to 2 out of 100 (1 to 2%) of all childhood-onset epilepsies.

  • Usually the first seizure occurs between 2 and 6 years of age.
  • Boys tend to be affected more than girls (two thirds to three quarters of children with MAE will be boys).
  • More than half of children start with a generalized tonic-clonic seizure with or without fever. Within days to months, drop seizures begin. Many children also develop myoclonic jerks and absence seizures, and some may develop tonic seizures. Most children with MAE are developing normally when seizures begin.

Is myoclonic atonic epilepsy genetic or inherited?

Genetics play an important role in this disorder. About 1 out of 3 families have a history of seizures.

While most children do not have an identified gene mutation, mutations in various genes, including SCN1A, SCN1B, SCN2A, SLC2A1, CHD2, SYNGAP1 and KIAA2022, have been identified in some cases. This epilepsy syndrome is considered part of a group of genetic epilepsies with febrile seizures plus (GEFS+).

What do the seizures in myoclonic atonic epilepsy look like?

Children with MAE may have multiple seizure types:

  • Drop seizures, characterized by an abrupt fall with loss of body tone (atonic) or by a brief body jerk followed by an abrupt fall (myoclonic atonic), occur in everyone.
  • Generalized tonic-clonic seizures are seen in most children. These may be triggered by fever.
  • Absence seizures and myoclonic seizures are seen in many cases.
  • Tonic seizures can be seen later in the course and often are predictive of poorer outcomes.

Though all seizure types can result in status epilepticus, about 1 in 3 children with MAE have episodes of non-convulsive status epilepticus. Seizures tend to occur more often early in the morning than during the day.

How is myoclonic atonic epilepsy diagnosed?

MAE is diagnosed based on the description of the seizures, with myoclonic atonic seizures being the most common type. Information also comes from tests such as:

  • EEG (electroencephalogram): children with MAE may have normal EEGs at first, but most have abnormal EEGs showing frequent generalized spike-wave activity in brief bursts of 2 to 5 Hz. Background may be normal or abnormal. (See the photo at the top of the page.)
  • MRI (magnetic resonance imaging) of the brain is normal.

How is myoclonic atonic epilepsy treated?

Medications

Seizures in children with MAE are often difficult to treat and may not respond well to medication. Medications are chosen based on the seizure types:

Some seizure medications should not be used in children with MAE because they can worsen certain seizure types. These include carbamazepine, oxcarbazepine, phenytoin, and vigabatrin.

Non-medication Therapies

The ketogenic diet is often very effective for MAE and should be considered early. Vagus nerve stimulation (VNS) has been used, but some reports have not shown benefit.

Rescue Therapies

Children with MAE who have long or clusters of seizures may need emergency medical treatment or treatment with a rescue therapy. Examples of rescue therapies may include diazepam rectal gel (Diastat) or another form of benzodiazepine given into the nose (intranasally) or under the tongue.

What is the outlook for children with myoclonic atonic epilepsy?

The prognosis for children with MAE can vary.

  • While seizures are often respond poorly to medication, about 2 out of 3 children ultimately outgrow their epilepsy and can wean off medication.
  • About one third have persisting seizures.
  • Development typically improves once seizures are controlled, with some children returning to normal function. Others may be left with varying degrees of intellectual disability.
  • Intellectual disability is more severe in children whose seizures do not go away and in those with tonic seizures and recurrent, non-convulsive status epilepticus.

Resources

Authored By: 
Angel Hernandez MD
Elaine Wirrell MD
Authored Date: 
11/2019
Reviewed By: 
Elaine Wirrell MD
on: 
Saturday, November 23, 2019