Ohtahara Syndrome (Early Infantile Epileptic Encephalopathy)
What is Ohtahara Syndrome?
Ohtahara syndrome is a very rare form of epilepsy sometimes referred to as ‘early infantile epileptic encephalopathy with suppression bursts’. It is named after the doctor who first described its symptoms in 1976, Dr Ohtahara. With this form of epilepsy, seizures begin before the age of 3 months old and may be linked to underlying abnormalities affecting the development or function of the brain.
What causes Ohtahara syndrome?
Some cases of Ohtahara syndrome are thought to be genetic, while others may occur as a result of damage to the brain either shortly before or after birth.
What are the symptoms?
In the majority of cases, babies suffer seizures within the first 10 days. There may be different types of seizure, including tonic spasms. These are characterised by the sudden onset of stiffness in the limbs, which usually passes quickly. Partial seizures, which cause jerky movements in one limb or on one side of the body, may also occur. These seizures can last anywhere from a few seconds to several minutes. Generalised seizures may also occur slightly later in life.
After the age of 6 months, the nature of seizures may change to a different type of seizure known as infantile spasm or West Syndrome. Babies also tend to lack balance and coordination.
How is Ohtahara syndrome diagnosed?
Doctors will ascertain a thorough description of the seizures and assess other symptoms when making a diagnosis. An EEG test will probably be ordered. This test, which is known as suppression burst, measures electrical activity in the brain and highlights any abnormal peaks and troughs, waves and discharge.
Antenatal diagnosis may be possible in cases where a genetic cause is identified during pregnancy.
Is there any cure?
In many cases, this form of epilepsy is resistant to some medications and it can take a period of trial and error to find a suitable treatment. Older medicines are usually tried before newer products. In cases where a baby has a focal structural abnormality (an abnormality that affects one part of the brain only), surgery may be recommended to remove the abnormality.
What is the prognosis?
Babies who have Ohtahara syndrome commonly suffer from delayed development and they often have feeding problems and they sleep much more than normal. Sometimes, as they get older, they suffer with stiffness in the limbs and development is very slow. Most children will need lifelong care. It is common for babies with this form of epilepsy to die before they reach the age of 2. The cause of death is often complications related to the syndrome, such as an increased risk of chest infections. In rare cases, when children live longer, they tend to have severe physical disabilities and will continue to experience seizures.