World Ohtahara Syndrome Awareness Day: What is Ohtahara Syndrome?

Ohtahara syndrome (OS) or early infantile epileptic encephalopathy (EIEE) is a severe type of epilepsy that typically affects newborns and infants, mainly within the first 3 months of their life. OS often results in seizures, intellectual disability, microcephaly and developmental delays. 

It is caused by unmanageable and frequent seizures, or metabolic disorders, genetic mutations, and brain malformations. However, sometimes, the exact cause is not known. The prognosis of Ohtahara syndrome is poor. Plenty of kids have profound disabilities or die in infancy. Kids with this syndrome may experience multiple seizures.

Ohtahara Syndrome Causes

Ohtahara syndrome can be caused by:

Metabolic disorders 

This is a rare cause of OS.

Structural Abnormalities

In most cases, this syndrome is caused by differences in how the brain has developed before birth. Usually, there is a serious atrophy of both brain hemispheres. Cerebral malformations are also one of the suspected causes.

Genetic Mutations

Another connection with OS could be multiple genes.

Life Expectancy Ohtahara Syndrome | Ohtahara Syndrome Life Span

Numerous kids with OS die within the first 2 years of life. Their life span is usually up to 3 years of age 1. It depends on the effects of secondary signs and seizure management. But there are certain exceptions. 

Few individuals may continue to live into adulthood. However, they have cognitive and physical limitations (like chest infections, excess fatigue, feeding difficulty, etc.), slow developmental progress and constant epilepsy. Also, few kids die in infancy while others stay but typically have serious handicaps.

Ohtahara Syndrome Symptoms

The main sign of this syndrome is frequent tonic seizures. This kind of seizure can lead to developmental delay and damage to the brain.

Kids with OS experience the first seizures before 3 months of age. Babies with it may have numerous types of seizures:

Tonic seizures

It’s the most common type that causes sudden stiffness in the legs, arms or the entire body. Other signs include dilated pupils, change in breathing, and upward eye gaze. Tonic seizures typically last for some seconds.

Focal seizures

Focal seizures include just one body part or one side of the body. It is characterized by constant jerking movements.

Generalized tonic-clonic seizures 

This type includes leg and arm movements (involving body sides of the body). Babies with it also experience jerking head or eye movements.

Myoclonic seizures

Myoclonic seizures are seizures that include constant jerking movements that affect single or both body sides. They are usually followed by sleeping and exhaustion.

Infantile spasms 

Infantile spasms are sudden brief movements of both or a single leg or arm and neck.

Diagnosis of Ohtahara Syndrome

Firstly, the doctor evaluates the developmental issues and seizure history of the child. Then, he/she conducts a physical exam. In case of worry about encephalitis (a brain infection), the professionals make additional tests mandatory.

Ohtahara syndrome is diagnosed using: 

a) A clinical exam (electroencephalogram (EEG) pattern) 

EEG displays a unique burst suppression pattern.

b) The underlying abnormalities in the brain. 

The doctor uses brain imaging tests to detect brain abnormalities, which could be:

• Genetic mutations
• Structural malformations
• Metabolic disorders which affect the brain’s working and development.

These are important to determine the signs of an OS. 

Ohtahara Syndrome Treatment

At present, there is no cure for Ohtahara syndrome. However, the following treatments can help manage the signs, depending on the cause and type of seizures. 

The main purpose of Ohtahara Syndrome Treatment is to minimize the seizures’ severity and frequency while giving supportive care for the family as well as the kid.

Ketogenic Diet 

Keto diet is a diet that is rich in fat and has low levels of carbs. In a few cases, it helps manage seizures.

Epilepsy Surgery

Another powerful treatment is epilepsy surgery. It is highly recommended when the doctor locates a focal brain lesion.

Anti-epilepsy Drugs (AEDs)

Anti-epilepsy drugs can manage seizures associated with the syndrome but they are usually resistant to drugs. That’s why it’s crucial to speak with a healthcare provider to determine the right AED.

Speech, Physical, and Occupational Therapies

Speech, physical and occupational therapies are another way to manage developmental challenges and improve the lives of patients.

Steroids 

Sometimes, the doctor uses high-dose steroids (like adrenocorticotrophic hormone (ACTH) to treat encephalopathy.

FAQ’s

How rare is ohtahara syndrome?

Ohtahara syndrome is quite rare. Its prevalence has been around 0.2 to 4% of all epilepsies in childhood. It means this neonatal epilepsy occurs in 1 in 100,000 births in Japan and 1 in 50,000 births in the U.K. These numbers are an estimate since neonates with Early Infantile DEE that die early may skip EEG and clinical diagnosis.

What is the new name for Ohtahara syndrome?

This rare epilepsy form is now called Early infantile epileptic encephalopathy (EIEE) or Early Infantile Developmental and Epileptic Encephalopathy (EIDEE).

Who is Ohtahara syndrome named after?

It is named after the Japanese child neurologist – Shunsuke Ohtahara, who first identified it in 1976. 

Is Ohtahara syndrome progressive?

Yes. This kind of syndrome is an early progressive neurological disorder. It leads to severe mental retardation and unmanageable seizures.