Current therapy of hypoparathyroidism — A survey of German endocrinology centers

Summary

Hypoparathyroidism is a rare disease with hypocalcemia as the leading symptom. In adults, hypocalcemia is mainly due to postoperative hypoparathyroidism. Hypoparathyroidism requires lifelong therapy with vitamin D or metabolites. Genuine vitamin D₃ (Vigantol^®) is the most economic treatment of hypoparathyroidism; however, vitamin D₃ has a very long biologic half life with the sub-sequent danger of chronic vitamin D intoxication. Dihydrotachysterol (A.T.I0^®), an analogue of vitamin D, acts similarly and can be used alternatively. 1,25-dihydroxivitamin D₃ (Rocaltrol^®), the biologically active metabolite of vitamin D₃, is very potent, but bears the danger of causing acute intoxication; it has a short half life and is more ex-pensive than vitamin D₃. A further metabolite, 1-hydroxy- vitamin D₃ (alfacalcidol, Doss^®, EinsAlpha^®) is available for therapeutic use. Clinical intervention trials concerning the best therapy and management of hypoparathyroidism are lacking. We therefore surveyed German physicians treating hypoparathyroidism. Furthermore, we carried out a retrospective study of 45 patients treated in our endocrinology department during the last 8 years and examined whether measurement of 25(OH)-vitamin D₃ is helpful in managing hypoparathyroidism. The data from 59 children and 270 adults could be completed in the survey. 1,25-di-hydroxyvitamin D₃ was the only vitamin D agent that was administered in the treatment of children, whereas in adults 52% were treated with dihydrotachysterol, 28% with genuine vitamin D₃, and 20% with 1,25-dihydroxyvitamin D₃. There was a positive correlation between serum 25(OH)-vitamin D₃ levels and administered vitamin D₃ doses. In patients treated with vitamin D₃, serum calcium levels correlated significantly with serum 25(OH)-vitamin D₃ levels whereas they did not correlate with administered calcium doses. Thus: (1) in Germany dihydrotachysterol is preferred for therapy of hypoparathyroidism in adults and (2) measurement of serum 25(OH)-vitamin D₃ may be helpful in assessing efficacy of therapy and compliance in patients treated with vitamin D₃.

Key words

Hypoparathyroidism - therapy - vitamin D