Ketogenic diet: Efficacy and tolerability in childhood intractable epilepsies

Introduction. Prospective study to evaluate efficacy of ketogenic diet (KD) in the treatment of children with intractable epilepsies (IE). Tolerability of the KD was also considered. Material and methods. Criteria for inclusion were: 1. Epilepsy refractary to treatments with antiepileptic drugs (AED) in monotherapy and combining two or three AED. 2. Acknowledgment of blood levels of these drugs in therapeutic range. 3. Absence of liver or kidney disease, metabolic abnormalities, inborn errors of metabolism or other progressive encephalopathies. 4. Family supposedly in economic and psychologic conditions to accept the difficulties of strictly maintaining KD. We used a classic KD following the criteria suggested by the John Hopkins Pediatrics Epilepsy Center. Baseline neurological and physical examination, EEG, blood chemistry including lipid profile were obtained prior to initiative and during the KD. KD efficacy was measured as percent reduction of baseline seizures frequency, considering positive results as reductions of 50% or over. Acceptance of the diet and quality of life were specially considered. Eighteen patients with ages from 2 to 11 years were admitted. Ten of them were males. Diagnosis followed the last Classification of Epileptic Syndromes of the ILAE, and distribution was: Symptomatic partial epilepsies, 8 cases (one had West syndrome at age 5 months); cryptogenic partial epilepsies, 1 case; Lennox-Gastaut syndrome 2 cases, severe myoclonic epilepsy of infancy, 6 cases and epilepsy with myoclonic astatic seizures 1 case. Results. Four patients were not able to achieve persistent ketosis either due to patient's rejection of KD or to parents non compliance. KD was kept for at least two months before considering failures. Five patients did not show significant improvement and KD was stopped. At present nine patients have been on KD from 6 to 24 months (average 16 months). Four of them showed a 75-100% reduction in seizures frequency and in three the reduction was of 50-75%. Conclusions. KD was fairly well tolerated by 14 of 18 children and their families. Fifty percent of the 14 patients complying KD showed significant improvement in seizure frequency and in quality of life. Due to the small number of patients and short follow-up, we can not speculate about results in relation to each epileptic syndrome neither the risk of late complications.