- Landau-Kleffner syndrome usually begins between 3 and 7 years of age.
- There is a progressive loss of speech.
- Seizures occur during sleep.
- This syndrome includes a loss of IQ.
What is it like? In the typical case, a child between 3 and 7 years of age experiences language problems, with or without seizures. The language disorder may start suddenly or slowly. It usually affects the child's understanding of spoken language the most, but it may affect both understanding speech and speaking ability, or it may affect speaking only.
Seizures are usually few and often occur during sleep. Simple partial seizures involving movement are most common, but tonic-clonic seizures can also occur.
Who gets it? The Landau-Kleffner syndrome is a rare disorder. It begins during childhood, with language disorders starting between ages 3 and 7 years.
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- Its symptoms are "acquired aphasia" (the loss of language abilities formerly present) and usually a seizure disorder. The children usually have generalized tonic-clonic and atypical absence seizures.
- The EEG is often the key to the diagnosis. A normal EEG, especially one done when the child is awake, does not rule out this disorder. Sleep activates the epilepsy waves in these children, so sleep recordings are extremely important. Sometimes the abnormality is seen only during sleep. The stage of sleep most affected is called slow-wave sleep, which usually does not begin until several hours after falling asleep. Therefore, routine 30-minute EEGs may miss the seizures in this condition.
- The boundaries of the Landau-Kleffner syndrome are imprecise. Some children may first have a delay in language development followed by a loss of speech milestones.
- Landau-Kleffner syndrome (or a variant of it) may also occur in some children in whom language function never develops, or in others whose language skills move backward but who very seldom have epilepsy waves on the EEG. The exact relationship between the epilepsy waves on the EEG and the language disorder is imprecise, although in some cases the epilepsy activity may contribute to the language problems.
How is it treated? Seizure control is rarely a problem, but standard seizure medications are not often effective against the language disorder. Drugs such as Lamictal (lamotrigine), Keppra (levetiracetam), and Depakote (valproate) sometimes help. High dose diazepam given at bedtime has resulted in excellent improvement in some children. Steroids have also shown some efficacy, improving both the EEG and language.
A new form of epilepsy surgery, multiple subpial transections in which multiple small slices are made in brain cortex, may improve both the EEG abnormalities and the language disorder in a small number of children. This procedure is still being studied in various epilepsy centers.
What's the outlook? After age 10, only 20% of patients still have seizures. The clinical course of the disorder fluctuates and it occasionally disappears on its own.
Some children are left with permanent language difficulties. Most commonly, these are children in whom medical or surgical therapy does not eliminate the epileptic patterns on the EEG.
Authored by: Gregory L. Holmes, MD | Robert S. Fisher, MD, PhD on 9/2013
Reviewed by: Robert S. Fisher, MD, PhD on 9/2013