[Pseudohypoparathyroidism type I and vitamin D therapy]

In pseudohypoparathyroidism type I pharmacologic dosis of vitamin-D can correct hypocalcemia. Several authors who had investigated vitamin-D-metabolism in these patients, found impaired renal conversion of 25-hydroxyvitamin-D to 1,25-dihydroxy-vitamin-D. Treatment of 2 patients with pseudohypoparathyroidism type I with vitamin-D-3 and 1 alpha-Hydroxycholecalciferol consecutively resulted in a nonuniform response with regard to the normalisation of serum-calcium. This led us to the conclusion that the disturbances of vitamin-D-metabolism in pseudohypoparathyroidism type I is heterogenous.