Definition:

Landau-Kleffner syndrome (LKS) is an epileptic encephalopathy that usually manifests itself in children aged 3-8 years with previously normal development. All LKS patients have abnormal EEG that is compatible with the diagnosis of epilepsy, however, only 70% have clinical seizures. The main symptoms are acute or subacute aphasia with inability to recognise, process or interpret verbal and/or non-verbal sounds. Although the exact etiology of LKS remains unclear, families with mutations in the GRIN2A gene have been described, in which some members have LKS. Recent reports have implicated susceptibility genes (SRPX2, ELP4) to idiopathic focal epilepsies.