Paradoxical exacerbation of myoclonic-astatic seizures by levetiracetam in myoclonic astatic epilepsy

BACKGROUND: Levetiracetam is a broad spectrum antiepileptic drug (AED) with proven efficacy when used as adjunctive therapy against myoclonic seizures. We report two patients suffering from epilepsy with myoclonic-astatic epilepsy (MAE) who experienced a paradoxical worsening of seizures after initiation of treatment with LEV, a finding not previously described. CASE PRESENTATION: Patients included were enrolled in an ongoing large prospective study evaluating children and adults with new onset epilepsy in Lebanon conducted at the American University of Beirut Medical Center in association with the Lebanese Chapter of the International League against Epilepsy. Based on an extensive evaluation, these patients were stratified into idiopathic partial, idiopathic generalized, symptomatic partial or symptomatic generalized epilepsies. Whenever possible the electroclinical syndrome was identified according to the ILAE classification of epilepsy syndromes. Patients were subsequently followed up on regular intervals and were assessed for adverse events, and seizure recurrence. MAE was diagnosed in five (1.6%) out of 307 consecutive children enrolled in this study. LEV was used as adjunctive therapy in four of those children with two experiencing a substantial and dose related worsening in the frequency of their myoclonic and atonic seizures. CONCLUSION: LEV should be used with caution in children with MAE and an exacerbation of seizure frequency temporally related to the introduction of LEV should alert the clinician to the possibility of a paradoxical seizure exacerbation.