Serum carnitine levels of children with epilepsy: Related factors including valproate

Abstract

Objective: This study measured the serum carnitine levels in patients with epilepsy and determined the factors contributing to low carnitine levels.

Methods: We measured the serum carnitine levels in 94 consecutive patients with epilepsy, including the free carnitine (FC) and acylcarnitine fractions, using an enzyme cycling method. We defined a low FC as a serum FC level < 36 μmol/L. Age, body mass index (BMI), standard deviation score of BMI (BMI-SDS), use of valproate, cognitive disorder, and feeding problems differed between patients with low and normal FC. In patients taking valproate, the associations of the serum FC level with the platelet count and serum ammonia and amylase levels were analyzed.

Results: Univariate analysis showed that a low BMI and BMI-SDS, the use of valproate, and cognitive disorder were more frequent in patients with a low FC. Logistic regression analysis revealed that a low BMI-SDS and cognitive disorders were independently associated with a low FC. Among the patients taking valproate, a low BMI-SDS and age were associated with a low FC. The serum FC and ammonia levels were inversely correlated, whereas no correlation was observed between the serum FC level and platelet count or serum amylase level.

Conclusion: A low BMI and cognitive disorders were related to a low FC in patients with epilepsy and the serum carnitine levels should be monitored in these patients.

Keywords: Ammonia; Body mass index; Cognitive disorder; Free carnitine; Valproate.