Abstracts

Rationale: Autosomal dominant lateral temporal epilepsy (ADLTE) is a rare epileptic syndrome inherited in autosomal dominant fashion with clinical features of lateral temporal epilepsy. ADLTE usually begins at childhood/adolescence and has benign prognosis. Mutations responsible for ADLTE were identified in the leucine-rich, glioma inactivated 1 gene (LGI1) on the chromosome 10q. Since the first description in 1995 by Ottman et al., ADLTE families have been reported in Europe, Australia, and Japan. Twenty-five LGI1 mutations were found in familial and sporadic lateral temporal epilepsy patients.Methods: We included a large family who are consistent with ADLTE in our data base. Blood samples of four patients among family members were tested for sequencing of the LGI1 gene and their medical records were reviewed.Results: Substitution mutation (C46F) in the exon 1 of the LGI1 was found in all tested patient. This mutation was not reported previously. It could result in the alteration of the amino acid sequence in the cysteine-rich region N-terminal to leucine-rich repeat region in the LGI1 protein. Functional effect of this mutation was not tested. Clinical seizures were occurred in adolescent period. Auras were visual hallucination, simple auditory hallucination, dizziness, and fear respectively. All patients did not have any neurologic deficits. Two patients were normal in both EEG and MRI. One patient (pt 3) showed synchronous bilateral mesial temporal spikes in the EEG and the other (pt 1) has old ischemic lesions in the bilateral deep white matter in MRI. Treatment responses were variable. Two patients (pt 1 & 3) are well controlled with AED monotherapy. Other two patients (pt 2 & 4) are experiencing complex partial seizure and generalized tonic clonic seizure despite of active AEDs treatment.Conclusions: New LGI1 mutation was identified in Korean ADLTE patients. The possible functional consequences of mutation were not yet elucidated. Clinical features were not homogenous among patients.