Levetiracetam-induced a new seizure type in a girl with a novel SV2A gene mutation.

The target brain binding site of levetiracetam (LEV) is synaptic vesicle glycoprotein 2A (SV2A). Up to now, only a homozygous pathogenic SV2A gene mutation was reported in human. We now report a novel heterozygous pathogenic SV2A gene mutation both in a girl and her mother result in epilepsy and poor response to LEV. Furthermore, the girl developed a new seizure type after using LEV. Our report had a clinical relevance that LEV could potentially produce contradictory efficacy in patients with SV2A gene mutation. If patients' seizures became exacerbated while using LEV, SV2A gene testing is recommended.