Landau-Kleffner Syndrome (LKS) Presenting with Acquired Aphasia and Absence Seizures: A Case Report

Abstract

Landau-Kleffner syndrome is an uncommon epileptic encephalopathy of childhood characterised by acquired language regression, epileptiform electroencephalographic abnormalities, seizures and variable behavioural disturbance. This case report describes a 7-year-old boy with a one-year history of recurrent absence seizures occurring approximately once every two to four days, with blank staring, unresponsiveness and bilateral eye blinking. Despite initiation of valproate therapy, the child developed progressive auditory and verbal aphasia over 7-8 months, followed by reliance on gestures for communication during the preceding 3 months. Behavioural changes included aggression, hyperactivity, tantrums and irritability. Prior development was reported as normal, with no relevant antenatal, family, psychiatric or chronic medical history. General examination, vital signs, routine laboratory investigations, fundoscopy and magnetic resonance imaging of the brain were unremarkable. Detailed neurological examination was limited by hyperactivity. Electroencephalography showed frequent focal epileptiform discharges, supporting the clinical diagnosis of Landau-Kleffner syndrome in the context of acquired aphasia, seizures and behavioural changes. Treatment included escalation of valproate from 20 mg/kg/day to 60 mg/kg/day, addition of oral clobazam at 1 mg/kg/day and intravenous methylprednisolone pulse therapy at 30 mg/kg/day for 5 days. Following treatment optimisation, seizure frequency decreased, behavioural symptoms improved and repeat electroencephalography showed reduced focal epileptiform discharges. The child subsequently regained coherent speech and was transitioned to oral prednisolone at 2 mg/kg/day for 2 weeks, followed by tapering over 4-6 weeks. At follow-up, he remained seizure-free on valproate and clobazam without further behavioural changes. Early recognition and individualised multimodal treatment may improve clinical outcomes in suspected Landau-Kleffner syndrome.