Corticosteroids for the treatment of Landau-kleffner syndrome and continuous spike-wave discharge during sleep.

Landau-Kleffner syndrome and its variants such as continuous Spike-Wave Discharge during Sleep (CSWS) are progressive epileptic encephalopathies of childhood. The treatment of this unusual group of patients is controversial. We describe our experience in treating patients with Landau-Kleffner syndrome and CSWS with corticosteroids. The patients received Prednisone 1 mg/kg/day for 6 months, 1 year, then yearly. Follow-up was for 1-10 years (mean 4 years). Ten patients, 3 females, 7 males were studied. Age of onset ranged from 2 to 11 years (mean 7.5 years). Eight patients manifested Landau-Kleffner syndrome, and two had CSWS. Most patients had seizures (8/10); however, two patients did not have clinical seizures. MRI was normal in all patients. SPECT scan was abnormal in four patients, normal in three, and not available in three. All but one patient manifested significant improvement in language, cognition, and behaviour, which continued after the corticosteroid trial. Side effects were few (4/10) and transient and consisted of weight gain (2), behavioral change (1), and hypertension (1). Corticosteroids are a safe and effective treatment for patients with Landau-Kleffner syndrome and CSWS. Most patients had improvement in language, cognition, and behaviour after treatment. Side effects are few and reversible, and benefits appear long lasting. Corticosteroids should be considered as a treatment option in children with Landau-Kleffner syndrome and CSWS.