[Phosphorus-calcium metabolism in children under long-term anticonvulsant therapy]

Abstract

The effects of prolonged administration of anticonvulsants were analyzed on different biochemical parameters related to phosphocalcium metabolism in 98 children aged 1 to 14, not affected by other chronic pathology, and to whom no Vitamin D nor other vitamin-mineral complexes had been administered. We take as reference a group of normal children studied during the same period. Determinations were accomplished with the usual chemical controls in our laboratory (autoanalysis of continuous flow, radioimmunoassay and colorimetric measurements) and the following mean levels were obtained for treated children: Calcium: 9.2 +/- 0.4 mg/dl, phosphorous: 3.5 +/- 1.9 mg/dl, alkaline phosphatase: 252 +/- 72 U/L, 25-Hydroxycholecalciferol: 35.6 +/- 18 ng/ml, Osteocalcine: 5.4 +/- 3.6 ng/ml, and parathyroid hormone: 0.4 +/- 0.1 ng/ml. These values differed significantly from those found in the control group for phosphorous, lower in children under treatment (p = 0.000), and the 25-Hydroxycholecalciferol was likewise lower (p = 0.000). In other way the mean levels of alkaline phosphatase were higher in treated children (p = 0.000). No significant differences were obtained for mean levels of calcium, parathyroid hormone and osteocalcine. These differences are maintained when distributing patients among different age groups. Solar radiation received by treated children during the months preceding the extraction, did not produce significant differences on 25-Hydroxycholecalciferol, with mean values that were similar at the end of summer (34 +/- 9 ng/ml) and the end of winter (36.6 +/- 18 ng/ml).