Long term treatment with teriparatide in severe cases of hypoparathyroidism

Abstract

Usual treatment may be insufficient in severe cases of hypoparathyroidism. Teriparatide (PTH1-34) is a therapeutical option for these patients. Objective: describe the biochemical response and bone densitometry in patients with hypoparathyroidism treated with PTH1-34. Materials and methods: clinical records of patients with hypoparathyroidism treated conventionally (calcium, calcitriol and thiazides) or with PTH1-34 were reviewed. Calcemia, phosphatemia, calciuria, calcium and calcitriol requirements, basal and after one year were compared. The evolution of laboratory parameters, bone densitometry and bone turn-over markers was analyzed in the PTH treated group during follow up. Results: eight women of 132 patients with hypopararathyroidism were treated with PTH1-34, (20-40 ug/d) from 9 months to 7 years. Patients with PTH replacement had frequent hospitalizations, lower calcemia (p=0.01), higher urinary calcium and phosphatemia (p=0.03; 0.02) and received higher calcium and calcitriol doses (p< 0.001) than the conventional group. After a year of treatment with PTH 1-34 serum calcium levels improved (p=0.018) and calcium and calcitriol requirement decreased (5.00 to 1.75 g/day, p=0.018 and 0.69 to 0.20 ug/day, p=0.002), and became similar to the conventionally treated group. Bone resorption markers increased initially with subsequent normalization. Densitometric changes were variable according to age and bone pre-treatment status. No serious complications were observed. Conclusion: PTH1-34 treatment can normalize serum calcium with lower calcium and calcitriol requirement in patients with severe hypoparathyroidism. Periodic bone densitometry testing is necessary, mainly in peri or post menopausal women. PTH replacement is an option to consider when hypocalcemia cannot be controlled with conventional therapy.