Difficult to control epilepsy in childhood--a long term study of 123 cases.

One hundred and twenty three children with difficult to control epilepsy (DCE) were studied. Etiological factors which predominated included an age of onset less than 2 years (71.5%), male sex (69%), mixed, secondarily generalized, or complex partial seizures (77%), mental retardation (64%) and neurological abnormalities (52%). Static neurological disease was seen in 63%, with only 17% having idiopathic disease. Identifiable epileptic syndromes were noted in less than half the children. The surface EEG was abnormal in 84%, and correlated with the clinical seizure type in 81%. CT and MRI were helpful in diagnosis in only 38 and 48%, respectively, and even less so in therapy decisions, 7 and 16%, respectively. Prior therapy revealed the use of polytherapy in 61% and suboptimal dosages in 78%. In the 100 patients with adequate follow up, 67% showed a good response, i.e., 35% complete and 32% more than 50% reduction in seizures. Only 11% were total nonresponders, and most were severely retarded. Major treatment strategies employed included switching to monotherapy, supranormal dosages and avoidance of sedative anticonvulsants. Side effects were noted in 41% with 8 cases being life threatening. Overall mortality was 4%. We concluded that risk factors for DCE included early age of onset, mental retardation and certain seizure types. EEG was more helpful than neuroimaging. Treatment responses were favorable, especially in those with normal intellect and the use of normal or high dose monotherapy.