Landau-Kleffner Syndrome


Landau-Kleffner syndrome (LKS) is a condition that shows up during childhood, causing difficulties with speech and seizures.

Children with LKS lose the ability to talk and understand speech. This loss is called aphasia.

Many children with LKS also have seizures, episodes of uncontrolled body movement.

This condition can be difficult to diagnose. The child may be misdiagnosed at first with autism, hearing loss or a learning disability.


The most common symptom of LKS is the loss of speech or the ability to understand speech. This change may happen slowly or it may be sudden. Symptoms of aphasia include:

  • Difficulty understanding words that were once familiar
  • Difficulty recognizing words that were once familiar

Patients with LKS often experience seizures during their sleep. These seizures are most often simple partial seizures. However, tonic-clonic seizures can also happen.

Behavioral problems may also develop including:

Causes and Risk Factors

LKS is very rare. It is most common in children between the ages of 3 and 7 years old.

LKS affects twice as many boys as girls.

The cause of LKS is unknown. Treatment that suppresses the immune system has been helpful for some children. This may suggest the condition is related to an autoimmune disorder.

At least one known case of LKS has been associated with a mutated gene known as GRIN2A.


LKS can be misdiagnosed. Parents should see their child's doctor if they notice unusual changes in their child's development. The doctor will ask about any symptoms the child is showing.

The most useful test in diagnosing seizures is an electroencephalogram (EEG). This records electrical activity in the brain. EEG can show unusual electrical activity patterns. Different types of seizures can be identified with these patterns.

Magnetic resonance imaging (MRI) and computed tomography (CT) scans may be used to study the condition. These images can also show where the seizure is happening in the brain. The scans can also rule out other possible causes such as unusual brain development.


Anti-seizure medication usually manages LKS seizures. These may include:

  • Valproate
  • Topiramate
  • Vitamin B6
  • Lamotrigine
  • Levetiracetam

Steroids, such as prednisone, have been shown to improve seizures and language skills. The steroid may be injected into the muscle. The steroid may also be taken by mouth.

A new surgery option for LKS is still being investigated. The surgery is called multiple subpial transections. It involves the surgeon making many small cuts into the brain's outer layer. This surgery has helped a small number of children and is still under evaluation.

The staff at the Cedars-Sinai Epilepsy Program will work with each patient to determine the best treatment option.

© 2000-2022 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Want More Information?

Cedars-Sinai has a range of comprehensive treatment options.

Looking for a Physician?

Choose a doctor and schedule an appointment.

Need Help?


Available 7 days a week, 6 am - 9 pm PT

Need Help?


Looking for a Physician

Choose a doctor and schedule an appointment.