DECREASED SERUM CONCENTRATIONS OF 1,25(OH)(2)-VITAMIN D-3 IN PATIENTSWITH GOUT

We measured serum concentrations of 1,25(OH)(2)-vitamin D-3, 25(OH)-vi tamin D-3, parathyroid hormone (PTH), and uric acid in 114 male patien ts with primary gout and 51 normal male control subjects, Serum 1,25(O H)(2)-vitamin D-3 was significantly lower in patients with gout compar ed with control subjects (38.4 +/- 11.9 v 44.4 +/- 11.0 pg/mL, P < .00 5), whereas no differences were observed between the two groups for se rum 25(OH)-vitamin D-3 or PTH. Serum uric acid was significantly highe r in patients with gout versus control subjects (8.8 +/- 1.3 v 5.7 +/- 1.0 mg/dL, P < .0001). In addition, there was a significant negative correlation between serum uric acid and 1,25(OH)(2)-vitamin D-3 concen trations (r-.17, P < .05), Administration of allopurinol or benzbromar one to the patients for 1 year caused a significant increase in serum 1,25(OH)(2)-vitamin D-3, which was associated with a significant decre ase in serum uric acid. In contrast, serum concentrations of 25(OH)-vi tamin D-3 and PTH were not affected by these drugs. These results sugg est that uric acid per se may directly decrease serum 1,25(OH)(2)-vita min D-3 in patients with gout by inhibiting 1 alpha-hydroxylase activi ty. Copyright (C) 1998 by W.B. Saunders Company.