Landau Kleffner Syndrome


This syndrome is also known as progressive epileptic aphasia and aphasia with convulsive disorder.

Landau-Kleffner syndrome (LKS) is a rare form of epilepsy.

  • LKS usually begins in children between 2 and 8 years old. The most common age of onset is 5 to 7 years of age. It affects both sexes equally.
  • A slow or sudden loss of the ability to understand speech or familiar sounds is typically seen in a child who has been developing appropriately.
  • While it usually affects the child's understanding of spoken language the most, it may affect both understanding speech and speaking ability. It can also affect the ability to recognize sounds in general. Children can seem to be deaf because of an inability to understand spoken language, but detailed tests of hearing are normal.
  • Attention deficit problems – with or without hyperactivity, anxiety, and aggression – can be seen in almost 8 out of 10 children.
  • Children who lose language because of LKS tend to be older than children that lose language because of autism spectrum disorders.

Seizures occur in 3 out of 4 children with this epilepsy syndrome.

The cause of LKS is unknown, though new (de novo) genetic mutations have been found in children. A gene called GRIN2A has been found in a small group of children with this condition but is not common. A family history of seizures can be seen but is not typical.

  • A thorough history is critical, with a description of any seizures, the child’s developmental course, and current abilities, specifically language use and processing.
  • An EEG (electroencephalogram), and in many instances a prolonged EEG or video EEG to capture sleep, is needed to diagnose LKS.
    • The EEG in children with this epilepsy syndrome is abnormal, especially as they enter sleep.
    • The spike discharges seen in LKS tend to become much more frequent during sleep as compared to wakefulness.
  • Electrical status epilepticus in sleep (ESES) is common.
    • High amplitude spike and sharp waves in the temporal and parietal lobes are typically the areas where these spikes occur. These are areas typically associated with speech.
    • This diagnosis can be missed if the EEG is only done while the child is awake.
  • Genetic and metabolic tests may be ordered.
  • An MRI (magnetic resonance imaging) scan is typically normal.

Seizures in children with LKS can be treated with anti-seizure medications. It is very important to also suppress the very frequent seizures during sleep. These seizures are thought to contribute to the speech and intellectual problems typical of LKS. Many antiseizure medications are not effective for that. In rare cases, surgery may be done.

  • Medications often used are steroids or a high dose diazepam at night. Other medications that have been used to treat this epilepsy syndrome include clobazam (Onfi), ethosuximide (Zarontin), valproic acid (Depakote/Depakene), acetazolamide (Diamox) and levetiracetam (Keppra). Often, more than one medicine is used at once.
  • Sometimes continous seizures in sleep persist despite medication. In those children, a type of epilepsy surgery called multiple subpial transections done at an epilepsy center may be an option. The benefit of this procedure is unclear.
  • Resective brain surgery is not usually an option.
  • Speech therapy should be started immediately in children with LKS.
  • Children may need to see a child psychologist, neuropsychologist, and/or psychiatrist to treat symptoms of ADHD (attention deficit hyperactivity disorder), anxiety, or aggression.
  • The outlook for recovering language is poor when LKS starts early in life or lasts for a long time without successful treatment.
  • Seizures and EEG abnormalities go away in most cases. After age 10, only 1 or 2 out of 10 children with LKS will still have seizures. The course of the disorder changes, and it occasionally disappears on its own.
  • Over 8 of 10 children are left with permanent language difficulties and in many instances these can be severe. This is most commonly seen in children when medical or surgical therapy does not eliminate the epileptic patterns on the EEG.
  • Successful improvement in cognition and language has been tied to improvement in the frequency of spike discharges during sleep (spike-wave index, SWI).
  • Relapses are common in LKS, so children need careful follow-up.

International League Against Epilepsy (ILAE) on Landau-Kleffner syndrome

National Institute of Neurological Disorders and Stroke (NINDS) at the National Institutes of Health (NIH) on Landau-Kleffner syndrome

National Organization for Rare Disorders (NORD) on Landau-Kleffner syndrome

Authored By:

Charuta Joshi MD
Michael Ciliberto MD

on Friday, February 14, 2020

Reviewed By:

Elaine Wirrell MD

on Thursday, February 13, 2020


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