An Overview of Doose Syndrome

Doose syndrome is a rare seizure disorder that begins during early childhood. This condition is also called myoclonic astatic epilepsy and myoclonic atonic epilepsy. 

Doose syndrome is considered a type of generalized epilepsy. The seizures of Doose syndrome may be difficult to manage with medication. As children reach adolescence or adulthood, they may improve, and treatment might not be required anymore.

Epilepsy is a tendency to have recurrent seizures. Doose syndrome is an epilepsy syndrome. There are a number of different epilepsy syndromes. Epilepsy syndromes have certain characteristic features—such as the age at which the seizures begin, the type and frequency of seizures, associated symptoms, and a hereditary pattern.

Symptoms

The first seizure of Doose syndrome generally begins between 7 months and 6 years old. The condition affects children who were previously healthy and who attained developmental milestones on time (such as walking, talking, and socializing). Recurrent seizures may begin weeks or months after the first seizure.

Seizure types that occur in Doose syndrome include: 

Atonic seizures: Atonic seizures involve a sudden loss of muscle tone and they may cause children to drop things or fall down. Children who experience atonic seizures are not conscious during the episodes and may not remember them. 

Myoclonic seizures: Myoclonic seizures are characterized by sudden jerking spasms of a muscle or group of muscles. Their duration may last between a few seconds to several minutes.

Myoclonic astatic seizures: This is a seizure type that does not commonly occur in other types of epilepsy besides Doose syndrome. This type of seizure begins as a myoclonic seizure and is then followed by an atonic episode.

Absence seizures: Absence seizures, which used to be called petit mal seizures, occur in many childhood epilepsy syndromes. These seizures are often described as staring spells. During these seizures, children are generally unresponsive and unaware of their surroundings for a few seconds.

Absence seizures do not involve shaking or jerking movements, and they don’t cause impairment of muscle tone. People do not remember the events that occurred during an absence seizure and cannot recall having had one. 

Generalized tonic-clonic seizures: Generalized tonic-clonic seizures are the type of seizures that involve jerking and shaking of both sides of the body with impaired consciousness. They are usually followed by severe fatigue.

Associated Symptoms

Some children who have Doose syndrome may experience other effects besides seizures.

Some children with Doose syndrome have ataxia (trouble with coordination), dysarthria (unclear speech), or features of autism (difficulty expressing themselves and interacting with others). 

Complications

Doose syndrome can cause several health problems that have long-term effects. Drop attacks are episodes of sudden falling that occur during or after a seizure. This can result in major physical injuries.

Status epilepticus is a seizure episode that does not resolve on its own. These seizures can interfere with breathing, and they require urgent medical intervention. Status epilepticus is an uncommon complication of Doose syndrome.

Developmental regression, which is loss of physical or cognitive abilities that have already developed, can occur as well. 

Causes

There are not known risk factors that are definitively linked with Doose syndrome and there is not usually a specific cause or trigger for the individual seizures. However, common seizure triggers, including fevers and fatigue, can trigger episodes. Photosensitive seizures, which occur in response to flashing lights, can occur as well.

The seizures that occur in Doose syndrome are generalized seizures, which means that they begin with abnormal nerve activity throughout the whole brain. This is in contrast to focal seizures, which begin with abnormal nerve activity in a small region of the brain, and may spread throughout the whole brain.

Generalized seizures cause impairment of consciousness. They can affect physical tone and movements, but they don’t necessarily do so. For example, absence seizures don’t affect muscle movement, but myoclonic seizures and atonic seizures do—and they all cause impairment of consciousness and a lack of awareness.

Genetics

Most children who are diagnosed with Doose syndrome have at least one family member with epilepsy. The condition has been thought to possibly have a genetic cause, but there is not a clear-cut hereditary pattern of inheritance.

Several genes have been linked to the condition, including SCN1A, SCN1B, GABRG2, CHD2, and SLC6A1. Changes in one or more of these genes may cause or predispose children to Doose syndrome.

Diagnosis

Certain features, including the seizure pattern, normal childhood development, a family history of epilepsy, and diagnostic test results, can identify Doose syndrome. 

With Doose syndrome, children usually have a normal physical examination, which is not expected to show signs of physical deficits or neurophysiological problems.

Electroencephalogram (EEG) 

Most children who have recurrent seizures will have an EEG. This test generally lasts for about half an hour, although an extended EEG or an overnight EEG can be done as well.

An EEG is a non-invasive brain wave test that measures the electrical activity of the brain in real time. During this test, your child would have small metal plates placed on their scalp. The plates detect the electrical pattern of the brain. Each plate is connected to a wire that sends a signal to a computer so the computer can read the electrical brain wave pattern.

Children with Doose syndrome have a certain pattern on their EEG. The test would show generalized (throughout the brain) spike wave activity at a frequency of 2 to 5 Hertz (Hz). These bursts of activity may occur frequently throughout the study. The overall background brain activity may be normal or abnormal when the spikes are not present.

Diagnostic Studies

Brain imaging tests, such as magnetic resonance imaging (MRI) or computerized tomography (CT), may be done as well. The brain structure as detected by imaging tests is typically completely normal in children who have Doose syndrome. 

In some instances, other tests such as blood tests, urine tests, and a lumbar puncture may be needed to rule out other causes of epilepsy. The results are expected to be normal in Doose syndrome.

Treatment

This condition may be difficult to treat. The anti-epilepsy drugs (AEDs) used for generalized epilepsy are not the same as those used for focal epilepsy. In fact, some AEDs used for treatment of focal seizures may actually worsen generalized seizures. 

AEDs commonly used in treatment of Doose syndrome include: 

• Depakote (valproate)
• Lamictal (lamotrigine)
• Keppra (levetiracetam)

Some children may experience improvement of seizures with one AED (monotherapy), and sometimes a combination of these medications may be necessary.

Steroid Treatments 

In addition to AEDs, other treatments may also be used for the management of seizures in Doose syndrome. Steroid medications, including adrenocorticotrophic hormone (ACTH), methylprednisolone, prednisone, or dexamethasone have been beneficial for some children who have this condition.

It is not completely clear why steroids may be beneficial. Steroids decrease inflammation and may alter hormone levels, and it has been suggested that the improvement could be related to one of these two actions. While neither hormones nor inflammation has been directly linked to Doose syndrome, some children nevertheless experience improvement after using these treatments.

Dietary Management 

The ketogenic diet is another approach that has been considered one of the strategies for managing seizures in refractory epilepsy, which is epilepsy that is not well controlled with AED medications.

The ketogenic diet is a high fat, adequate protein, and extremely low carbohydrate diet. It is believed to control seizures through a physiological process called ketosis, in which the body forms ketones due to a type of metabolic breakdown that occurs in the absence of carbohydrate intake.

This diet is extremely difficult to maintain, and it is not effective unless it is strictly followed. That is why it is not usually considered a desirable approach unless medication is not effective for controlling seizures. Children who are on this diet may crave sugar, bread, or pasta—and if they can physically reach for food, young children often are not able to follow the diet as strictly as needed.

While it can help reduce seizure frequency, the ketogenic diet can cause elevated fat and cholesterol levels.

If your child is prescribed the ketogenic diet, it is a good idea to find a support group of other parents whose children are following the ketogenic diet so you can share recipes and strategies.

In some circumstances, epilepsy surgery may be considered for children who have Doose syndrome.

A Word From Verywell

If your child has been diagnosed with Doose syndrome or any type of epilepsy, it is natural to be concerned about their health. Most types of epilepsy are manageable with anti-seizure treatments. Severe health consequences (such as a major injury or death) are very rare.

As your child gets older, they will be better able to understand their condition and can play a greater role in taking their own medication. As your child learns to recognize the feelings that may occur prior to the onset of seizures (a seizure aura) they can try to take a break from what they are doing, and reduce the chance of injuries that may result from a seizure episode.