An 8-year-old girl with Landau-Kleffner syndrome failed to respond to antiepileptic drugs and steroids but showed clinical and EEG improvement after intravenous g-globulin therapies at the American University of Beirut School of Medicine, Lebanon. Mumps at 5 years of age was complicated by receptive and expressive aphasia. An EEG showed generalized spike and slow waves, and a trial of valproate (VPA) was ineffective. At 6 years, the neurologic exam, apart from aphasia, the CT and MRI were normal, and the EEG showed almost continuous left-sided spike and slow wave complexes, resistant to VPA, clonazepam, and prednisone. Three courses of iv immunoglobulins, 400 mg/kg/day for 5 days, at 6-month intervals, resulted in a normal EEG and near-normal speech. CSF IgG index, previously increased, returned to normal after the first iv infusion. 
COMMENT. Landau-Kleffner syndrome (LKS) has multiple etiologies, including meningitis, demyelination, arteritis, and cerebral neoplasms. Trials of AEDs and corticosteroids have been disappointing, providing at best some temporary relief. The present case report with dramatic response to immunotherapy suggests a postencephalitic autoimmune abnormality, and further studies are indicated. The late Dr Frank Morrell advocated subpial intracortical transection in selected cases of LKS. (see Progress in Pediatric Neurology III, 1997;p86).