Long-term follow-up of the ketogenic diet for refractory epilepsy: Multicenter Argentinean experience in 216 pediatric patients

PURPOSE In this Argentinean retrospective, collaborative, multicenter study, we examine the efficacy and tolerability of the ketogenic diet (KD) for different epilepsy syndromes. MATERIALS AND METHODS we evaluated the clinical records of 216 patients started on the KD between March 1, 1990 and December 31, 2010. RESULTS One hundred forty of the initial patients (65%) remained on the diet at the end of the study period. Twenty-nine patients (20.5%) became seizure free and 50 children (36%) had a 75-99% decrease in seizures. Thus, 56.5% of the patients had a seizure control of more than 75%. The best results were found in patients with epilepsy with myoclonic-astatic seizures, Lennox-Gastaut syndrome, and West syndrome. Good results were also found in patients with Dravet syndrome, in those with symptomatic focal epilepsy secondary to malformations of cortical development, and in patients with tuberous sclerosis. Seizures were significantly reduced in four patients with fever-induced refractory epileptic encephalopathy in school-age children and in two patients with epileptic encephalopathy with continuous spikes and waves during slow sleep. The median period of follow-up after discontinuation of the diet was 6 years. Twenty patients who had become seizure free discontinued the diet, but seizures recurred in five (25%). Of 40 patients with a seizure reduction of more than 50% who discontinued the diet, 10 presented with recurrent seizures. CONCLUSION The ketogenic diet is a good option in the treatment of refractory epilepsy. After discontinuing the diet, seizures recurrence occurred in few patients.