MINERAL'NAYa PLOTNOST' KOSTII POKAZATELI KOSTNOGO METABOLIZMAU PATsIENTOV S IDIOPATIChESKIM VARIANTOM TsENTRAL'NOGO NESAKhARNOGO DIABETA (TsND)

Abstract

Central diabetes insipidus is a rare pituitary disease due to impairment of synthesis or/and secretion of vasopressin (AVP), characterized by polyuria, polydipsia, low urine osmolality and hyperosmolality of plasma. Main therapy for CDI is substitutive therapy with desmopressin. Lately, it has been shown that AVP stimulates bone formation through the induction of PG synthesis in mesangial cells, contributing to prevent osteoporosis. Pivonello et al. (1998) found that patients with CDI even on nasal desmopessin therapy had a significant impairment in BMD and serum osteocalcin. The aim of this study was to assess the biochemical parameters of bone metabolism and the bone mineral density (BMD) in patients with idiopathic variant of CDI, treated with oral desmopressin. In 24 patients with idiopathic CDI, treated with oral desmopressin and 24 healthy controls we evaluated BMD (analyzer Prodigy, Lunar, DXA), serum osteocalcin (OK) and C-terminal telopeptide of type I collagen (CTx), (ECLIA, Roche Elecsys 1010/2010) as well as calcium total, ionized calcium and alkaline phosphatase (analyzer Hitachi 912, commercial kits Roche). Anterior pituitary dysfunction and concomitant conditions associated with osteoporosis were eliminated on clinical and laboratory basis. The results showed no significant differences between study groups with the exception for ionized calcium which was higher in the group of CDI (p=0,02). We were not able to confirm detrimental effects of idiopathic CDI on BMD and biochemical markers of bone metabolism.