The Landau-Kleffner syndrome is a childhood disorder consisting of acquired aphasia and epileptiform discharges involving the temporal or parietal regions of the brain.74-89
The typical sequence is as follows:
In the original description of the syndrome, verbal auditory agnosia was the language disturbance,81 but some patients may have expressive aphasia early in the course.
Only about 70% of patients have seizures. In one-third of cases, a single seizure or status epilepticus occurs, usually early in the course of the syndrome. The seizures usually begin in children who are between 5 and 10 years of age. After age 10, only 20% of patients still have seizures. The patients usually have generalized tonic-clonic and atypical absence seizures. Complex partial seizures with automatisms are uncommon.
In addition to aphasia, most patients have behavioral and psychomotor disturbances that may suggest autism. The neurologic examination, except for the mental status examination, is usually normal.
The clinical course of the disorder fluctuates85,88 and spontaneous remissions can occur.
The EEG is nonspecific in this syndrome. Typical EEG findings are frequent and repetitive spikes, sharp waves, and spike-and-wave activity. Usually, the discharges are bilateral and located in the temporal region or parietal-occipital region.
Sleep usually activates the record, and at times the abnormality is seen only in sleep recordings.79,88 Often patients will have continuous spike-and-wave activity during sleep. There appears to be an overlap between Landau-Kleffner syndrome and the syndrome known as continuous spike-wave discharges during sleep (CSWDS).
Reviewed and revised January 2004 by Gregory L. Holmes, MD, Dartmouth Medical School
© 2014 Epilepsy.com. All rights reserved.