MILD NON-LESIONAL TEMPORAL-LOBE EPILEPSY - A COMMON, UNRECOGNIZED DISORDER WITH ONSET IN ADULTHOOD

Objective: To compare mild vs. severe non-lesional temporal lobe epile psy (TLE). Methods: Data from 104 consecutive patients with non-lesion al TLE were reviewed, Seventy-three of the 104 fulfilled the criteria for inclusion in this study of a follow-up period longer than three ye ars at our Institute. Patients were considered to have a mild TLE if t hey were seizure free for at least three years after appropriate antie pileptic medication, or had rare (less than or equal to 2/year) comple x partial or secondarily generalized seizures for at least three years with or without appropriate antiepileptic therapy. Clinical, EEG and MRT data of mild vs. severe non-lesional TLE patients were compared on the basis of a cross-sectional study design. Results: Of the 73 patie nts with non-lesional TLE included in the study, 43 (59%) had mild TLE , and 30 (41%) had severe TLE. Duration of epilepsy was significantly shorter (mean 15.2 +/- 10.5 years vs. 26.4 +/- 13.2 years) and age at onset was significantly higher (mean 34.3 +/- 15.3 years vs. 7.8 +/- 6 .8 years) in mild than in severe TLE group. Patients with mild TLE had also a significantly higher prevalence of positive family history of epilepsy (37.2% vs, 10%), and a significantly lower occurrence rate of febrile convulsions (FC) (4.7% vs. 33.30%), mesial temporal sclerosis (MTS) (6.9% vs. 36.7%), and intelligence deficiency (0% vs. 20%). In mild TLE there was also a significantly high rate (58.1% vs. 0%) of de layed diagnosis (from 1 to 28 years), because of misdiagnosis (39.5%) or no medical counseling (18.6%). Conclusions: Mild non-lesional TLE i s a common,unrecognized disorder mainly characterized by both onset in adulthood and high prevalence of familial history of epilepsy. The pr esent findings suggest that mild non-lesional TLE may represent a clin ical entity different from severe non-lesional TLE.