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.
The Landau-Kleffner syndrome is a rare disorder. It begins during childhood, with language disorders starting between ages 3 and 7 years.
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.
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.