What is Landau-Kleffner Syndrome?
The Landau-Kleffner syndrome (acquired epileptic aphasia) is another rare disorder. “Acquired aphasia” means the loss of language abilities that had been present. In the typical case, a child between 3 and 7 years of age experiences progressive language problems, with or without seizures. The language disorder may start suddenly or slowly. It usually affects auditory comprehension (understanding spoken language) the most, but it may affect both understanding speech and speaking ability, or it may affect speaking only. Seizures are usually rare and often occur during sleep. Simple partial motor seizures are most common, but tonic-clonic seizures can also occur. Seizure control is rarely a problem.
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 abnormal spike activity, and therefore sleep recordings are extremely important.
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 abilities. 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 spike-wave discharges on the EEG. The exact relationship between the EEG findings and the language disorder is imprecise, although in some cases the epilepsy activity may contribute to the language problems.
How is Landau-Kleffner Syndrome Treated?
Standard antiepileptic drugs may help the seizures but are ineffective in treating the language disorder. Steroids are effective in some children, improving both the EEG abnormalities and the language problems. A form of epilepsy surgery, multiple subpial transections, may improve both the EEG abnormalities and the language disorder in a small number of children, but results to confirm this finding are still coming in from various epilepsy centers. In some cases intravenous immune globulin (IVIG) has proven to be helpful.