Abstracts

Rationale: The ketogenic diet (KD) is a high-fat, low-protein, very low-carbohydrate diet used in the treatment of medically refractory epilepsy in children. Its anticonvulsant mechanism is not clear but alterations in brain amino acids have been proposed as a mechanism of action. We investigated the influence of the KD on levels of metabolites of dopamine, serotonin and norepinephrine and related the changes to seizure control. Methods: As CSF levels of the mother substances are low we analyzed the end products of dopamine namely HVA, of serotonin, 5-HIAA and of norepinephrine, HMPG. These levels were determined before as well as 3 months after initiation of the KD in 26 children (mean ±SD 5.9 ±2.9 years) with severe epilepsy. The majority were on a KD ratio of 4:1 (fats:proteins and carbohydrates). Seizures were quantified. Results: The CSF levels of HVA and 5-HIAA decreased significantly in relation to the diet (p=0.0002 and p=0.004). The levels of HMPG were unchanged. Seventeen of the 26 children were seizure responders. However, no correlation was found between seizure response and levels of HVA, 5-HIAA or HMPG. Conclusions: The HVA and 5-HIAA levels in CSF, which should reflect the levels of dopamine and serotonin, were significantly changed following the introduction of the KD. Even though a correlation to seizure response was not found, one can not exclude that these changes could be involved in the mechanism of action of the diet.