Abstracts

Rationale: The objective of this study is to assess total and free carnitine levels for patients on the classic and medium chain triglyceride (MCT) ketogenic diets. Carnitine is required for the transport of long-chain fatty acids into the mitochondria for beta-oxidation. Carnitine also plays a role in the metabolism of dietary medium-chain fatty acids. Both the classic and MCT ketogenic diets are high fat diets, with fats comprising 71-90% of the daily caloric intake. Carnitine deficiency has been documented in children treated with the classic diet, but not the MCT diet. We report on carnitine deficiency in children receiving dietary treatments for epilepsy. Methods: Total and free carnitine levels were measured prospectively prior to diet initiation and at 3, 6, 12, 18 and 24 months follow-up in children aged 1-16 years (mean±SD = 5.4±3.6) treated with dietary therapies for epilepsy from January 2006 to May 2008 . Forty-one children were treated with the classic diet and 18 children were treated with the MCT diet. Levocarnitine supplementation was used for children with low carnitine levels at a dosage of 50-100 mg/Kg body weight to return carnitine levels to the normal range. Results: Prior to initiation of the classic ketogenic diet, seven children (17%) had low free carnitine level (mean±SD=20.8±3.6 umol/L) and 1 (<1%) child had low total carnitine level (16.6 umol/L). At follow-up, 39 (95%) children had at least one low free carnitine level (mean±SD = 18.3±4.3 umol/L) (normal range:26.0-60.0 umol/L) and 11 (27%) children had at least one low total carnitine level (mean±SD=20.5±4.1 umol/L) (normal range: 32.0-84.0 umol/L). Prior to initiation of the MCT diet, 3 (17%) children had low free carnitine levels (mean±SD=19.1±5.9 umol/L) and one (<1%) had a low total carnitine level (27.6 umol/L). At follow-up, 8 (44%) children had at least one low free carnitine level (mean±SD=20.7±4.2 umol/L) and none had a low total carnitine level. Treatment with the MCT diet is less likely to be associated with carnitine deficiency than the classic ketogenic diet.