Ketogenic diet in patients with Dravet syndrome

The ketogenic diet (KD) has been used as a therapeutic alternative to antiepileptic drugs (AEDs) for refractory epilepsy. Severe myoclonic epilepsy in infants or Dravet syndrome (DS) is one of the most malignant epileptic syndromes. In this retrospective study, we evaluated the efficacy and tolerability of the KD in patients with diagnostic criteria of DS.

Between March 1, 1990, and August 31, 2004, 52 patients who met diagnostic criteria for DS were enrolled in a study at our department. Twenty of them were placed on the KD with the Hopkins protocol and followed up for a minimum of 1 year.

Three of the 20 original children stayed on the diet for 12 months, four children for 2 years, four children for 3 years, and two children for 4 years. One year after initiating the diet, 13 (65%) of the initial patients remained on the diet. Two (15%) patients were seizure free, eight (61.7%) children had a 75-99% decrease in seizures, and the remaining three (23%) children had a 50-74% decrease in seizures. Thus 1 year after starting the diet, 10 (77%) children had achieved a >75% decrease in their seizures. Four patients have been off the diet for >2 years; one of them is seizure free, two have sporadic seizures, and one, who abandoned the diet after 2 years of adhering to it, relapsed. No differences in seizure control when compared with age, sex, or seizure type were found.

Considering the severity and intractability of seizures in patients with DS, the fact that 10 of the 13 children who remained on the diet had a significant reduction in number of seizures shows that the KD is at present an interesting therapeutic alternative. Even in patients in whom seizure reduction was not dramatic, quality of life improved, and in all of them, the number of AEDs was reduced to one or two. We consider that children with DS should be offered the KD immediately after three adequate trials of AEDs have failed.