Abstracts

Rationale: Clinical characteristics of medial temporal lobe epilepsy (MTLE) with hippocampal atrophy (HA) by CNS infection as epileptic substrate might be different from those of conventional MTLE. The clinical variables affecting the prognosis between CNS infection-related and conventional MTLE with HS were analyzed. Methods: Thirty seven MTLE patients with antecedent history of CNS infection and 117 patients with conventional MTLE were recruited. All patients showed isolated HS on brain MRI. Clinical profiles such as demographic data, antecedent etiologies, semiologic features of TLE including characteristics of seizure (accompanied tonic-clonic attacks, clustering nature, nocturnal preponderance), laterality of HA on MRI, and prognosis were compared between the 2 groups. The minimal follow up duration for analysis of prognosis was two years. The prognosis of patients who had undergone epilepsy surgery was based on a 12-month follow-up before the surgery. Statistically significant prognostic variants were identified using multiple regression analysis. Results: Simple comparison showed statistically difference in the onset age of epilepsy, laterality of HA on MRI, and prognosis. Clinical covariates affecting prognosis with statistical significance were CNS infection, automatism, and nocturnal preponderance. Multiple logistic regression analysis showed the presence of CNS infection and automatism worked as negative prognostic factor with 5.5 and 2.5 folds respectively. In contrast, nocturnal preponderance did as positive prognostic factor with 3.4 folds. Conclusions: These results showed that there were some clinical differences, especially in the prognosis between CNS infection-related MTLE and conventional MTLE with HA. The presence of CNS infection and automatism were associated with a poor prognosis, while nocturnal preponderance as a good prognosis between two groups.