Arginine-vasopressin response to supine-erect posture change: an index for evaluation of the integrity of the afferent component of baroregulatory system in diabetic neuropathy.

The arginine-vasopressin (AVP) response to supine-standing postural change was evaluated in eight healthy subjects and in fourteen diabetic patients. Plasma AVP levels were found to increase in the controls and in nine subjects from the diabetic group. In the controls the increase was 139% 5 min. after standing and 275% 120 min. after standing. In four of the diabetics affected by autonomic neuropathy AVP failed to increase in response to standing, thus suggesting lesions of the neurogenic pathways connecting baroreceptors to neurohypophysis. Consequently, a failure of the afferent limb in the baroregulatory system must be taken into account among other localizations of autonomic neuropathy. On this basis, AVP measurement both in supine and erect positions could represent an additional test for assessing the integrity of the autonomic nervous system

HypoparaNet: A Database of Chronic Hypoparathyroidism Based on Expert Medical-Surgical Centers in Italy.

Hypoparathyroidism is a rare disease characterized by low serum calcium levels and absent or deficient parathyroid hormone level. Regarding the epidemiology of chronic hypoparathyroidism, there are limited data in Italy and worldwide. Therefore, the purpose of this study was to build a unique database of patients with chronic hypoparathyroidism, derived from the databases of 16 referral centers for endocrinological diseases, affiliated with the Italian Society of Endocrinology, and four centers for endocrine surgery with expertise in hypoparathyroidism, to conduct an epidemiological analysis of chronic hypoparathyroidism in Italy. The study was approved by the Institutional Review Board. A total of 537 patients with chronic hypoparathyroidism were identified. The leading etiology was represented by postsurgical hypoparathyroidism (67.6%), followed by idiopathic hypoparathyroidism (14.6%), syndromic forms of genetic hypoparathyroidism (11%), forms of defective PTH action (5.2%), non-syndromic forms of genetic hypoparathyroidism (0.9%), and, finally, other forms of acquired hypoparathyroidism, due to infiltrative diseases, copper or iron overload, or ionizing radiation exposure (0.7%). This study represents one of the first large-scale epidemiological assessments of chronic hypoparathyroidism based on data collected at medical and/or surgical centers with expertise in hypoparathyroidism in Italy. Although the study presents some limitations, it introduces the possibility of a large-scale national survey, with the final aim of defining not only the prevalence of chronic hypoparathyroidism in Italy, but also standards for clinical and therapeutic approaches