[Renal tubular acidification in patients treated with anticonvulsants (author's transl)]

Proximal and distal renal tubular acidification function has been studied in ten epileptics treated with phenobarbital and hydantoins. Plasma concentration of 25 OH D3 and urinary excretion of adenosine 3':5'-cyclic phosphate (cAMP) were also determined. Serum parathormone (PTH) was analyzed in five patients. Four of these ten patients showed a decreasing threshold for bicarbonates, suggesting a disturbance of the proximal tubular acidification function. These patients did not show diminishing plasma levels of 25 OH D3, and according to the results of cAMP and PTH determinations a hyperparathyroidism could be ruled out. Anticonvulsants lead to a disturbance of the renal acidification which is not derived from alterations of the phosphocalcic metabolism.