VALPROATE THERAPY DOES NOT DEPLETE CARNITINE LEVELS IN OTHERWISE HEALTHY-CHILDREN

Objective. To determine whether children with epilepsy undergoing valp roate (VPA) antiepileptic therapy and who are otherwise healthy have a lower serum level of carnitine (CAR) and a higher plasma level of pla sma ammonia than do normal children. Methodology. A total of 45 childr en with epilepsy, 6.3 to 21.7 years of age, who were treated solely wi th VPA and were free of abnormal neurologic findings or nutritional pr oblems were randomly selected (VPA-treated group). An age-matched cont rol group (n = 45) was selected from subjects without epilepsy (contro l group). Total (T) and free (F) serum CAR, serum VPA concentration, a nd the plasma ammonia level were measured and analyzed. Results. Serum VPA concentration exhibited a weak negative correlation with both T- (r = -0.34) and F-CAR (r = -0.41). The T-CAR levels were 55.7 +/- 12.4 and 57.6 +/- 12.1 mM, and the F-CAR levels 42.7 +/- 9.9 and 44.4 +/- 9.9 mM in the VPA-treated and control groups, respectively. Thus, ther e was no significant difference in T- or F-CAR levels between the VPA- treated and control groups. Plasma ammonia levels were the same in the two groups: 26 +/- 9.2 and 29.4 +/- 11.8 mM in the VPA-treated and co ntrol groups, respectively. There was no significant correlation betwe en blood ammonia and either T- (r = + 0.024) or F-CAR (r = -0.026). Co nclusion. Children on a regular diet ingest a sufficient amount of CAR that more than meets their daily CAR requirement. The level of neithe r T- nor F-CAR in patients with epilepsy and without severe neurologic or nutritional problems being treated with VPA appeared to be affecte d by VPA therapy. Because the blood CAR level depends on nutritional c ondition rather than on blood VPA concentration, CAR deficiency caused by VPA is not likely to occur in this population. The usefulness of s upplementation of CAR for this type of patient with epilepsy, therefor e, must be reevaluated carefully.