Ketogenic Diet in Refractory Epilepsy: efficacy, evolution and long-term complicationsBackground: Ketogenic diet (KD) represents an alternative in treatment of refractory epilepsy (RE). Objective: To evaluate the efficacy of the diet and the frequency of complications in patients belonging to the KD Program from Luis Calvo Mackenna Children's Hospital (HLCM). Methods: Evaluation of all children enrolled in the program between 1999 and 2004, with analysis every 6 months of the diet efficacy, digestive tolerance, nutritional status, cholesterol levels and nephrolithiasis. Results: 21 children were admitted, 14 boys, age between 6 months -17 years-old. 76%, 71% and 67% of patients followed KD at 6, 12 and 18 months, respectively, with KD efficacy of 67%. At 12 months, 24% of patients did not present seizures. At 18 months, 85% remained close to ideal body weight (15% obesity) and height/age Z score decreased (-0,7 ± 0,4; p < 0,05). Total cholesterol significantly increased at 6 months (64% hypercholesterolemia; decreased to 15% at 18 months). 2 patients developed nephrolithiasis. Conclusions:The study shows high efficacy of the KD for treatment of refractory epilepsy, with low rate of complications. It should be considered as a therapeutic alternative for these patients. (