Endocrine Abstracts

Serum 25-hydroxy-vitamin D (25OHD) is considered the most reliable marker of vitamin D status. Adequate levels 25OHD of are necessary for pleiotropic effects of vitamin D, either skeletal or extra-skeletal. Traditional assays based on immunoassay often show an unsatisfactory accuracy and sensibility. A valuable alternative is Tandem Mass Spectrometry coupled to High Performances Liquid Chromatography (HPLC-MS-MS), that offers a good quantification accuracy, as the contribution...

Thyroid hormones stimulates bone turnover. Increased blood levels of thyroid hormones are associated with a negative balance at individual bone remodeling unit and bone loss. It is well know that hyperthyroidism is a common cause of secondary osteoporosis and increased risk of fragility fractures. Mild hyperthyroidism (suppressed TSH and normal free thyroid hormones), as observed in autonomous thyroid nodules or following administration of TSH-suppressive doses of thyroid horm...

Normocalcemic primary hyperparathyroidism (NC-PHPT) is a condition characterized by normal albumin-adjusted total serum calcium or ionized calcium and persistently elevated serum PTH. Therefore, to recognize this entity it is necessary to measure PTH in normocalcemic individuals. The question arises why would someone measure PTH in a normocalcemic subject? A pro-active approach to women evaluated in their early postmenopausal years for parameters of skeletal health as well as ...

Pseudohypoparathyroidism type 1 A (PHP-1A) is a rare genetic disorder characterized by hypocalcemia, hyperphosfatemia, multi hormones resistance (PTH, TSH, Calcitonin, GH) associated with Albright hereditary osteodystrophy (AHO) features. The disease is caused by GNAS haploinsufficiency due to inherited inactivating mutation of GNAS-gene that codes for the stimulatory alfa subunit of G protein. A positive genotype-phenotype correlation was recently hypothesized. The purpose of...

Context: Vitamin D deficiency following malabsorptive bariatric surgery can lead to osteomalacia. We report a patient with severe vitamin D deficiency following malabsorptive bariatric surgery successfully treated with calcifediol but not cholecalciferol.Case description: A 40-year-old woman, submitted to biliopancreatic diversion 20 years before and chronically treated with 50 000 IU cholecalciferol weekly, was admitted to our Endocrine Unit because of ...

X-linked hypophosphatemia (XLH), representing about 80% of hypophosphatemic rickets, is an X-linked dominant disease due to inactivating mutations in the PHEX gene (located at Xp22.1) resulting in an excessive secretion of the phosphaturic hormone fibroblast growth factor 23 (FGF23). The effects are renal phosphate wasting and reduced active vitamin D synthesis leading to rickets, osteomalacia, bone deformities, odontomalacia, frequent dental abscesses and disproporti...

Hypoparathyroidism (HypoPT) is the only hormone deficiency syndrome whose standard treatment is not based on the replacement of the missing hormone. Although most cases of postsurgical HypoPT can be effectively managed with the conventional use of oral calcium and active vitamin D (SOC therapy), some patients require very high doses and develop complications such as hypercalciuria, renal stones, nephrocalcinosis and ectopic calcifications. In the last few years, recombinant hu...

Objectives: A sporadic association between thyroid and non-organ-specific autoimmunity has been reported, which could be relevant for Graves’ orbitopathy (GO), an autoimmune disease affecting orbital connective tissue. We investigated whether there is an association between GO and anti-nuclear antibodies (ANAs).Methods: We performed a cross-sectional investigation in 265 consecutive patients with Graves’ disease (GD) who came to our observation...

Objectives: A role of IgG4 in Graves’ disease (GD) has been proposed, although the available data are conflicting. In addition, an association between Graves’ orbitopathy (GO) and IgG4-related disease has been postulated, but no firm demonstration has been obtained. Thus, the aim of the present study was to investigate the role of IgG4 in GD.Methods: We performed a cross-sectional investigation in 351 consecutive patients (F=284, M=67; age 48.2...

Context: Mutations of cytochrome P450 24 subfamily A member 1 (CYP24A1) gene are associated with Idiopathic Infantile Hypercalcemia (IIH), a disease recently related to vitamin D catabolism impairment.Aim of the study: Report of clinical and biochemical features of a large family with a novel mutation of CYP24A1.Methods: We performed dosage of total calcium, ionized calcium, 24 h urinary calcium, PTH, 25-OH-Vitamin D (25-O...