Comparative and serial assays of folate metabolism in anticonvulsant-treated epileptics.

A prospective study of folate metabolism has been conducted in outpatient anticonvulsant-treated epileptics on 68 occasions. An attempt was made to compare the relative sensitivities of serum and red cell measurements of folic acid, lactic dehydrogenase (LD), and 2 hydroxybutyric dehydrogenase (2HBD). The most sensitive indices of folate deficiency appeared to be serum folate, red cell LD, red cell folate, and red cell 2HBD, respectively. The correlation between these measurements was not close, except in comparisons of red cell and serum folate. No easily performed screening test for folate deficiency emerged. Serial changes in these measurements were carried out on 15 patients during an interval of 18 months. No progressive signs of folate depletion appeared during this time. The significance of these findings is discussed.