What You Need To Know About ESES Epilepsy

Electrical status epilepticus during slow-wave sleep (ESES) is a rare form of epilepsy characterized by seizures during sleep. This type of epilepsy occurs in children and adolescents. Seizures are followed by a slow cognitive decline, often presenting as behavioral problems. 

ESES occurs in children with a mean age of onset between the ages of four to eight. ESES is more common in males. It can last several months to a few years but generally resolves itself before adulthood. However, the cognitive impairments may extend beyond the end of the seizures. 

The seizures that occur during ESES are most commonly focal motor seizures. In focal seizures, only one side of the brain is affected. But these seizures are not only limited to nighttime. Some children experience absence seizures during the day and even myoclonic jerk seizures.¹ 

Aside from the seizures, the key differentiating feature of this form of epilepsy is that you may notice your child’s learning abilities start to drop significantly. This may present as a lowering in intelligence, difficulties with language, and changes in behavior, including aggression and hyperactivity. It can also impact social development and motor skills. 

What causes ESES? 

The ultimate cause of ESES is currently unknown. Some cases are linked to brain abnormalities like stroke or hydrocephalus. It can also be related to metabolic conditions. Around 10%² of patients have a genetic link to ESES.

Some research³ has identified that these seizures originate in the thalamus. The thalamus is an important relay center in the brain. Your body is constantly taking in information via your senses, and this information must pass through the thalamus before it can be sent for processing. 

A hyperactive circuit within the thalamus is thought to be responsible for abnormal EEG activity during sleep. This malfunctioning within the hypothalamus may be responsible for impaired information processing and memory.

That’s because the information your body receives from the outside world can’t be correctly relayed through the thalamus and sent to the appropriate part of your brain for processing. 

How is ESES epilepsy diagnosed?  

Your doctor will start by getting a comprehensive medical history to identify when the seizures commenced and other behavioral changes that have occurred and may be related. Then they will perform an electroencephalogram (EEG). An EEG measures the electrical activity of your brain by attaching small metal discs to your scalp. 

As these seizures often occur during sleep, a long EEG may be required to capture abnormalities. This can be achieved either through taking a video or overnight admission to the hospital. 

Your doctor will look for continuous spike and slow-wave epileptic activity during your child’s slow-wave sleep. Slow-wave sleep occurs around 20-30 minutes into sleep and is part of the deeper sleep cycle. 

Identifying and diagnosing ESES epilepsy as early as possible is important because there is a significant correlation between delayed diagnosis and permanent cognitive impairments. An early diagnosis will allow your child to receive treatment for the seizures and address the changes to their learning needs in the school environment. 

Treatment

ESES is treated with anti-seizure medication. Medication may be prescribed independently or combined with others, depending on your child's needs. The goal is to reduce their seizures and return their EEG to normal while improving their cognitive symptoms. 

Valproate, ethosuximide, and levetiracetam are the most common medications prescribed. Steroid medications, including methylprednisolone, prednisolone, and ACTH are also used to treat ESES. A recent review⁴ found that steroids are the most effective treatment for ESES. However, given how rare ESES is, different doctors may have different treatment protocols as the research on best practices is still limited. 

Surgery for these seizures is uncommon but possible for your child. In some cases, children have been treated with a ketogenic diet. However, this method has only been trialed in studies with a few patients, so its effectiveness remains unknown. 

What is the outlook for people with ESES? 

Most children start seeing improvements in ESES as they reach their teenage years. Seizures drop in frequency and, for some, disappear altogether. Your child may have their EEG pattern return to normal during sleep. Other children may find that their overnight EEG recording abnormalities may persist into adulthood. 

Most children find that their speech and language skills improve when seizure frequency drops. However, this does not mean that all children return to normal learning environments, as many are left with learning difficulties and behavioral problems due to seizures.

The lowdown

ESES epilepsy is a rare form of epilepsy resulting in seizures and cognitive decline in children. Changes in learning and behavior may persist into adulthood for some. 

Consequently, it’s important to provide your child with adequate care outside prescription medications. Their recovery may not follow a straight line, so you must take the proper steps so that their school and home environment supports them every step of the way.