Effect of an oral dose of 25-hydroxyvitamin D3 on its blood levels in patients with the nephrotic syndrome

Abstract

Patients with the nephrotic syndrome have low blood levels of 25-hydroxyvitamin D3 (25OHD3) due to urinary losses of the sterol. It is not known whether supplementation of this metabolite could raise its blood levels in these patients. The changes in the plasma levels of 25OHD3 and its kinetic behavior were studied after an oral dose of the sterol (200 microgram) in patients with the nephrotic syndrome in an effort to evaluate the usefulness of oral therapy to achieve and maintain normal blood levels of 25OHD3. Normal subjects served as controls. The results showed that intestinal absorption of 25OHD3 is significantly delayed and its elimination rate is significantly enhanced in patients with the nephrotic syndrome compared to control subjects. Despite these abnormalities, the plasma levels of 25OHD3 were within normal values even 48 h after the ingestion of the sterol. These data indicate that oral therapy with 25OHD3 given in proper doses is adequate to maintain normal blood levels of the sterol in patients with the nephrotic syndrome. Therefore, a therapeutic approach could be designed to manage the target organ disease due to 25OHD3 deficiency seen in these patients.