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Context: Atypical parathyroid tumor (APT) represents a neoplasm characterized by histological features typical of parathyroid carcinoma (PC) but lacking local infiltration and/or distant metastasis, leading to uncertainty regarding its malignant potential., Objective: To characterize the molecular landscape and deregulated pathways in APT., Methods: Whole exome sequencing (WES) was conducted on 16 APTs. DNA from tumors and matched peripheral blood underwent WES using Illumina HiSeq3000., Results: A total of 192 nonsynonymous variants were identified. The median number of protein-altering mutations was 9. The most frequently mutated genes included BCOR, CLMN, EZH1, JAM2, KRTAP13-3, MUC16, MUC19, and OR1S1. Seventeen mutated genes belong to the Cancer Gene Census list. The most consistent hub genes identified through STRING network analysis were ATM, COL4A5, EZH2, MED12, MEN1, MTOR, PI3, PIK3CA, PIK3CB, and UBR5. Deregulated pathways included the PI3 K/AKT/mTOR pathway, Wnt signaling, and extracellular matrix organization. Variants in genes such as MEN1, CDC73, EZH2, PIK3CA, and MTOR, previously reported as established or putative/candidate driver genes in benign adenoma (PA) and/or PC, were also identified in APT., Conclusions: APT does not appear to have a specific molecular signature but shares genomic alterations with both PA and PC. The incidence of CDC73 mutations is low, and it remains unclear whether these mutations are associated with a higher risk of recurrence. Our study confirms that PI3 K/AKT/mTOR and Wnt signaling represents the pivotal pathways in parathyroid tumorigenesis and also revealed mutations in key epigenetic modifier genes (BCOR, KDM2A, MBD4, and EZH2) involved in chromatin remodeling, DNA, and histone methylation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Parathyroid carcinoma (PC) is usually associated with severe symptomatic primary hyperparathyroidism (PHPT) and accounts for less than 1% of all cases of PHPT and approximately 0.005% of all cancers. PC most commonly occurs as a sporadic disease and somatic CDC73 mutations can be detected in up to 80% of cases. Approximately 30% of patients harbor a germline mutation of the CDC73 gene. Preoperative diagnosis of PC is difficult because no disease-specific markers are available, and PC should be suspected in patients with severe hypercalcemia and end-organ complications. The diagnosis is based on the evidence of invasive tumor growth at histology and/or metastases. En bloc resection of the tumor, together with the ipsilateral thyroid lobe and adjacent structures, should be performed by an experienced surgeon when PC is suspected. This surgical approach reduces the risk of recurrence and metastasis and offers the highest chance of cure. Nonetheless, PC has a recurrence rate of 40% to 60% and, if feasible, multiple surgical procedures should be performed. When surgery is no longer an option, medical treatment is aimed to reduce hypercalcemia and target organ complications. Targeted agents have been effectively used in a few cases. We describe herein a patient with severe PHPT due to PC and provide a systematic diagnostic and treatment approach. A thorough review of the medical history, a typical clinical and biochemical phenotype and, in some cases, the revision of the histological examination provide the clues for the diagnosis of PC., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: A role of DNA methylation in Graves orbitopathy (GO) has been proposed., Objective: This work aimed to investigate DNA methylation and gene expression in orbital fibroblasts from control and GO patients, under basal conditions or following challenge with an anti- thyrotropin (TSH) receptor antibody (M22) or cytokines involved in GO; to investigate the relationship between DNA methylation and cell function (proliferation); and to perform a methylome analysis., Methods: Orbital fibroblasts from 6 GO and 6 control patients from a referral center underwent methylome analysis of the whole genome., Results: Global DNA methylation increased significantly both in control and GO fibroblasts on incubation with M22. Expression of 2 selected genes (CYP19A1 and AIFM2) was variably affected by M22 and interleukin-6. M22 increased cell proliferation in control and GO fibroblasts, which correlated with global DNA methylation. Methylome analysis revealed 19 869 DNA regions differently methylated in GO fibroblasts, encompassing 3957 genes and involving CpG islands, shores, and shelves. A total of 119 gene families and subfamilies, 89 protein groups, 402 biological processes, and 7 pathways were involved. Three genes found to be differentially expressed were concordantly hypermethylated or hypomethylated. Among the differently methylated genes, insulin-like growth factor-1 receptor and several fibroblast growth factors and receptors were included., Conclusion: We propose that, when exposed to an autoimmune environment, orbital fibroblasts undergo hypermethylation or hypomethylation of certain genes, involving CpG promoters, which results in differential gene expression, which may be responsible for functional alterations, in particular higher proliferation, and ultimately for the GO phenotype in vivo., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Hypercalcemia of malignancy (HCM) is the most common metabolic complication of malignancies, but its incidence may be declining due to potent chemotherapeutic agents. The high mortality associated with HCM has declined markedly due to the introduction of increasingly effective chemotherapeutic drugs. Despite the widespread availability of efficacious medications to treat HCM, evidence-based recommendations to manage this debilitating condition are lacking., Objective: To develop guidelines for the treatment of adults with HCM., Methods: A multidisciplinary panel of clinical experts, together with experts in systematic literature review, identified and prioritized 8 clinical questions related to the treatment of HCM in adult patients. The systematic reviews (SRs) queried electronic databases for studies relevant to the selected questions. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence and make recommendations. An independent SR was conducted in parallel to assess patients' and physicians' values and preferences, costs, resources needed, acceptability, feasibility, equity, and other domains relevant to the Evidence-to-Decision framework as well as to enable judgements and recommendations., Results: The panel recommends (strong recommendation) in adults with HCM treatment with denosumab (Dmab) or an intravenous (IV) bisphosphonate (BP). The following recommendations were based on low certainty of the evidence. The panel suggests (conditional recommendation) (1) in adults with HCM, the use of Dmab rather than an IV BP; (2) in adults with severe HCM, a combination of calcitonin and an IV BP or Dmab therapy as initial treatment; and (3) in adults with refractory/recurrent HCM despite treatment with BP, the use of Dmab. The panel suggests (conditional recommendation) the addition of an IV BP or Dmab in adult patients with hypercalcemia due to tumors associated with high calcitriol levels who are already receiving glucocorticoid therapy but continue to have severe or symptomatic HCM. The panel suggests (conditional recommendation) in adult patients with hypercalcemia due to parathyroid carcinoma, treatment with either a calcimimetic or an antiresorptive (IV BP or Dmab). The panel judges the treatments as probably accessible and feasible for most recommendations but noted variability in costs, resources required, and their impact on equity., Conclusions: The panel's recommendations are based on currently available evidence considering the most important outcomes in HCM to patients and key stakeholders. Treatment of the primary malignancy is instrumental for controlling hypercalcemia and preventing its recurrence. The recommendations provide a framework for the medical management of adults with HCM and incorporate important decisional and contextual factors. The guidelines underscore current knowledge gaps that can be used to establish future research agendas., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Pharmacological therapy may be useful in the treatment of moderate to severe hypercalcemia in patients with infantile hypercalcemia-1 (HCINF1) due to pathogenic variants in the cytochrome P450 24 subfamily A member 1 (CYP24A1). Rifampin is an antituberculosis drug that is a potent inducer of cytochrome P450 3 subfamily A member 4, which is involved in an alternative catabolic pathway of vitamin D. The efficacy of rifampin in improving hypercalcemia was previously reported, but many questions remain on the long-term efficacy and safety. The aim of the study is to test the long-term efficacy and safety of rifampin in a patient with HCINF1., Methods: We report clinical, biochemical, and imaging features of a 23-year-old man affected by HCINF1 with moderate hypercalcemia (12.9 mg/dL), symptomatic nephrolithiasis, nephrocalcinosis, and impaired kidney function [estimated glomerular filtration rate (eGFR) 60 mL/min/1.73 m2] treated with rifampin for an overall period of 24 months. Kidney, liver, and adrenal function were evaluated at every follow-up visit., Results: In 2 months, rifampin induced a normalization of serum calcium (9.6 mg/dL) associated with an improvement of kidney function (eGFR 92 mL/min/1.73 m2) stable during the treatment. After 15 months, rifampin was temporally withdrawn because of asthenia, unrelated to impairment of adrenal function. After 3 months, the timing of drug administration was shifted from the morning to the evening, obtaining the remission of asthenia. At the end of follow-up, the nephrolithiasis disappeared and the nephrocalcinosis was stable., Conclusions: Rifampin could represent an effective choice to induce a stable reduction of calcium levels in patients with HCINF1, with a good safety profile., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Measurement of circulating microRNAs (miRNAs) as potential biomarkers of fragility fracture risk has recently become a subject of investigation., Objective: Measure by next-generation sequencing (NGS), global miRNA expression in serum samples of osteoporotic subjects vs individuals with normal bone mineral density (BMD)., Design: Samples were collected from patients with different bone phenotypes and/or fragility fractures who did not receive any antiresorptive and/or bone-forming drug at the time of blood collection., Setting: Samples and data were collected at 7 medical centers in Italy., Patients: NGS prescreening: 50 osteoporotic patients vs 30 individuals with normal BMD. Droplet digital polymerase chain reaction (ddPCR) validation: 213 patients with different bone phenotypes, including the NGS-analyzed cohort., Results: NGS identified 5 miRNAs (miR-8085, miR-320a-3p, miR-23a-3p, miR-4497, miR-145-5p) differentially expressed in osteoporosis cases without fractures vs controls. ddPCR validation confirmed lower c-miR-23a-3p expression in osteoporotic patients, with or without fracture, than in osteopenic and normal subjects and increased c-miR-320a-3p expression in osteoporotic patients with fracture and lower expression in osteoporotic patients without fracture. ddPCR analysis showed a significantly increased expression of miR-21-5p in osteoporotic patients, with or without fracture, than in osteopenic and normal subjects, not evidenced by the NGS prescreening., Discussion: Our study confirmed levels of c-miR-23a-3p and c-miR-21-5p as able to distinguish osteoporotic patients and subjects with normal BMD. Increased levels of c-miR-320a-3p specifically associated with fractures, independently by BMD, suggesting c-miR-320a-3p as a prognostic indicator of fracture risk in osteoporotic patients, to be confirmed in prospective studies on incident fractures., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Hypoparathyroidism is characterized by insufficient levels of parathyroid hormone (PTH). TransCon PTH is an investigational long-acting prodrug of PTH(1-34) for the treatment of hypoparathyroidism., Objective: This work aimed to investigate the safety, tolerability, and efficacy of daily TransCon PTH in adults with hypoparathyroidism., Methods: This phase 2, randomized, double-blind, placebo-controlled 4-week trial with open-label extension enrolled 59 individuals with hypoparathyroidism. Interventions included TransCon PTH 15, 18, or 21 µg PTH(1-34)/day or placebo for 4 weeks, followed by a 22-week extension during which TransCon PTH dose was titrated (6-60 µg PTH[1-34]/day)., Results: By Week 26, 91% of participants treated with TransCon PTH achieved independence from standard of care (SoC, defined as active vitamin D = 0 μg/day and calcium [Ca] ≤ 500 mg/day). Mean 24-hour urine Ca (uCa) decreased from a baseline mean of 415 mg/24h to 178 mg/24h by Week 26 (n = 44) while normal serum Ca (sCa) was maintained and serum phosphate and serum calcium-phosphate product fell within the normal range. By Week 26, mean scores on the generic 36-Item Short Form Health Survey domains increased from below normal at baseline to within the normal range. The Hypoparathyroidism Patient Experience Scale symptom and impact scores improved through 26 weeks. TransCon PTH was well tolerated with no treatment-related serious or severe adverse events., Conclusion: TransCon PTH enabled independence from oral active vitamin D and reduced Ca supplements (≤ 500 mg/day) for most participants, achieving normal sCa, serum phosphate, uCa, serum calcium-phosphate product, and demonstrating improved health-related quality of life. These results support TransCon PTH as a potential hormone replacement therapy for adults with hypoparathyroidism., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

Context: Atypical parathyroid adenomas (APAs) are neoplasms with uncertain malignant potential but lack unequivocal histological signs of malignancy., Objective: This work aims to retrospectively evaluate the clinical and biochemical profiles of patients with APA, the outcome after parathyroidectomy (PTX), and the presence of CDC73 germline and somatic mutations., Methods: This monocentric study was conducted on consecutive patients undergoing PTX for primary hyperparathyroidism (PHPT) between June 2000 and December 2020. Fifty-eight patients with a confirmed histopathological diagnosis of APA, and age- and sex-matched controls with parathyroid adenoma (PA) were also included., Results: Fifty-four patients had sporadic PHPT and 4 had familial isolated hyperparathyroidism (FIHP). Thirty-four patients (59%) had symptomatic disease. Serum calcium and parathyroid hormone (PTH) levels were significantly higher in symptomatic compared to asymptomatic patients (P = .048 and .008, respectively). FIHP patients were younger than their sporadic counterparts (30 ± 17 years vs 55 ± 13 years). APA patients had significantly higher serum calcium and PTH levels and lower 25-hydroxyvitamin D concentration, bone mineral density, and T score at one-third distal radius compared to those with PA. Four of 56 APA patients displayed a CDC73 germline mutation. No somatic CDC73 mutation was identified in 24 tumor specimens. The mean follow-up after surgery was 60 ± 56.4 months. All but 6 patients (90%), 5 with apparently sporadic PHPT and 1 with FIHP, were cured after surgery., Conclusion: The large majority of patients with APA, despite a moderate/severe phenotype, have a good prognosis. Germline CDC73 mutation-positive patients had a higher rate of persistent/recurrent disease. CDC73 gene alterations do not seem to have a relevant role in the tumorigenesis of sporadic APA., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Pseudohypoparathyroidism (PHP) is a group of disorders characterized by hypocalcemia, hyperphosphatemia, and elevated parathyroid hormone (PTH) levels as a result of end-organ resistance to PTH., Objective: To describe a cohort of 26 patients with PHP followed in a single tertiary center., Methods: Clinical, biochemical, radiological, and genetic analysis of the GNAS gene in 26 patients recruited since 2002., Results: Ten patients harbored a GNAS mutation, 15 epigenetic abnormalities at the GNAS locus, and 1 did not show genetic or epigenetic abnormalities. According to clinical, biochemical, and genetic features, patients were classified as PHP1A, PHP1B, and pseudopseudohypoparathyroidism. Patients with PHP1A had an earlier diagnosis and more cases with family history, Albright hereditary osteodystrophy (AHO) features, hormonal resistance, and hypertension. Obesity was a common feature. No difference in biochemical values was present among PHP1A and PHP1B. Intracerebral calcification occurred in 72% of patients with no difference among PHP1A and PHP1B subgroups. No significant difference was observed between patients with and without intracerebral calcification for the time-weighted average values of total serum calcium, phosphate, calcium-phosphate product, and PTH fold increase. A borderline association between cerebral calcification and age at the time of diagnosis (P = .04) was found in the whole cohort of patients. No renal calcifications were found in the overall cohort., Conclusion: Patients with PHP1A more frequently have AHO features as well as hypertension than patients with PHP1B. Patients with PHP presented a high rate of intracerebral calcification with no significant difference between subgroups. No increased risk of renal calcifications was also found in the entire cohort., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Graves' orbitopathy (GO) is an autoimmune disease that persists when immunosuppression is achieved. Orbital fibroblasts from GO patients display peculiar phenotypes even if not exposed to autoimmunity, possibly reflecting genetic or epigenetic mechanisms, which we investigated here., Objective: We aimed to explore potential genetic or epigenetic differences using primary cultures of orbital fibroblasts from GO and control patients., Methods: Cell proliferation, hyaluronic acid (HA) secretion, and HA synthases (HAS) were measured. Next-generation sequencing and gene expression analysis of the whole genome were performed, as well as real-time-PCR of selected genes and global DNA methylation assay on orbital fibroblasts from 6 patients with GO and 6 control patients from a referral center., Results: Cell proliferation was higher in GO than in control fibroblasts. Likewise, HA in the cell medium was higher in GO fibroblasts. HAS-1 and HAS-2 did not differ between GO and control fibroblasts, whereas HAS-3 was more expressed in GO fibroblasts. No relevant gene variants were detected by whole-genome sequencing. However, 58 genes were found to be differentially expressed in GO compared with control fibroblasts, and RT-PCR confirmed the findings in 10 selected genes. We postulated that the differential gene expression was related to an epigenetic mechanism, reflecting diverse DNA methylation, which we therefore measured. In support of our hypothesis, global DNA methylation was significantly higher in GO fibroblasts., Conclusions: We propose that, following an autoimmune insult, DNA methylation elicits differential gene expression and sustains the maintenance of GO., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Human cytochrome P450 24 subfamily A member 1 (CYP24A1) loss-of-function mutations result in impaired activity of the 24-hydroxylase involved in vitamin D catabolism, thus inducing a vitamin D-dependent hypercalcemia. Homozygotes often present an overt clinical phenotype named idiopathic infantile hypercalcemia (IIH), whereas it is debated whether heterozygotes display an abnormal phenotype., Objective: To compare the clinical and biochemical features of heterozygous carriers of CYP24A1 variant and healthy wild-type controls sharing the same genetic and environmental exposure., Methods: A large family harboring the nonsense c.667A>T, p.Arg223* pathogenic variant in the CYP24A1 gene was evaluated. All subjects underwent clinical and biochemical evaluation and complete analysis of vitamin D metabolites using mass spectroscopy including 1,24,25(OH)3D3. Subjects were divided into 2 groups according to their genotype: heterozygotes and wild-type for the CYP24A1 variant., Results: The proband, a 40-year-old man, homozygous for p.Arg223* pathogenic variant, had a history of mild hypercalcemia with a seasonal trend, recurrent nephrolithiasis, and no episodes of acute hypercalcemia. He showed the highest serum levels of fibroblast growth factor 23, the highest 25(OH)D3/24,25(OH)2D3 ratio and undetectable levels of 1,24,25(OH)3D3, which represent indicators of a loss-of-function CYP24A1. Compared with the wild-types, heterozygotes had higher serum calcium and 25(OH)D3 concentrations (P = .017 and P = .025, respectively), without any difference in the other biochemical parameters and in the rate of nephrolithiasis., Conclusion: Heterozygotes exhibit a biochemical phenotype different from that of wild-type subjects. In clinical practice, these individuals might require surveillance because of the potential risk of developing hypercalcemia and related clinical manifestations if exposed to triggering factors., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: The pathogenesis of nephrolithiasis in primary hyperparathyroidism (PHPT) remains to be elucidated. The latest guidelines suggest parathyroidectomy in patients with asymptomatic PHPT with hypercalciuria (> 400 mg/d) and increased stone risk profile., Objective: The objective of this work is to evaluate the association of urinary stone risk factors and nephrolithiasis in patients with asymptomatic sporadic PHPT and its clinical relevance., Design: A total of 157 consecutive patients with sporadic asymptomatic PHPT were evaluated by measurement of serum and 24-hour urinary parameters and kidney ultrasound., Results: Urinary parameters were tested in the univariate analysis as continuous and categorical variables. Only hypercalciuria and hypomagnesuria were significantly associated with nephrolithiasis in the univariate and multivariate analysis adjusted for age, sex, body mass index, estimated glomerular filtration rate, parathyroid hormone, 25-hydroxyvitamin D, serum calcium, and urine volume (odds ratio, OR 2.14 [1.10-4.56]; P = .04; OR 3.06 [1.26-7.43]; P = .013, respectively). Hypomagnesuria remained associated with nephrolithiasis in the multivariate analysis (OR 6.09 [1.57-23.5], P = .009) even when the analysis was limited to patients without concomitant hypercalciuria. The urinary calcium/magnesium (Ca/Mg) ratio was also associated with nephrolithiasis (univariate OR 1.62 [1.27-2.08]; P = .001 and multivariate analysis OR 1.74 [1.25-2.42], P = .001). Hypomagnesuria and urinary Ca/Mg ratio had a better, but rather low, positive predictive value compared with hypercalciuria., Conclusions: Hypomagnesuria and urinary Ca/Mg ratio are each associated with silent nephrolithiasis and have potential clinical utility as risk factors, besides hypercalciuria, for kidney stones in asymptomatic PHPT patients. The other urinary indices that have been commonly thought to be associated with kidney stones in PHPT are not supported by our results., (© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Immune checkpoint inhibitors (ICIs), such as programmed cell death protein-1 (PD-1), programmed cell death protein-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen-4 (CTLA-4) monoclonal antibodies, are approved for the treatment of some types of advanced cancer. Their main treatment-related side-effects are immune-related adverse events (irAEs), especially thyroid dysfunction and hypophysitis. Hypoparathyroidism, on the contrary, is an extremely rare irAE., Objectives: The aim of the study was to investigate the etiology of autoimmune hypoparathyroidism in a lung cancer patient treated with pembrolizumab, an anti-PD-1., Methods: Calcium-sensing receptor (CaSR) autoantibodies, their functional activity, immunoglobulin (Ig) subclasses and epitopes involved in the pathogenesis of autoimmune hypoparathyroidism were tested., Results: The patient developed hypocalcemia after 15 cycles of pembrolizumab. Calcium levels normalized with oral calcium carbonate and calcitriol and no remission of hypocalcemia was demonstrated during a 9-month follow-up. The patient was found to be positive for CaSR-stimulating antibodies, of IgG1 and IgG3 subclasses, that were able to recognize functional epitopes on the receptor, thus causing hypocalcemia., Conclusion: The finding confirms that ICI therapy can trigger, among other endocrinopathies, hypoparathyroidism, which can be caused by pathogenic autoantibodies., (© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: It is not known whether total thyroidectomy is more favorable than medical therapy for patients with amiodarone-induced thyrotoxicosis (AIT)., Objective: To compare total thyroidectomy with medical therapy on survival and cardiac function in AIT patients., Methods: Observational longitudinal cohort study involving 207 AIT patients that had received total thyroidectomy (surgery group, n = 51) or medical therapy (medical therapy group, n = 156) over a 20-year period. AIT types and left ventricular ejection fraction (LVEF) classes were determined at diagnosis of AIT. Cardiac and thyroid function were reevaluated during the study period. Survival was estimated using the Kaplan-Meier method., Results: Overall mortality and cardiac-specific mortality at 10 and 5 years, respectively, were lower in the surgery group than in the medical therapy group (P = 0.04 and P = 0.01, respectively). The lower mortality rate of the surgery group was due to patients with moderate to severely compromised LVEF (P = 0.005 vs medical therapy group). In contrast, mortality of patients with normal or mildly reduced LVEF did not differ between the 2 groups (P = 0.281 and P = 0.135, respectively). Death of patients with moderate to severe LV systolic dysfunction in the medical therapy group occurred after 82 days (interquartile range, 56-99), a period longer than that necessary to restore euthyroidism in the surgery group (26 days; interquartile range, 15-95; P = 0.038). Risk factors for mortality were age (hazard ratio [HR] = 1.036) and LVEF (HR = 0.964), whereas total thyroidectomy was shown to be a protective factor (HR = 0.210). LVEF increased in both groups after restoration of euthyroidism, above all in the most compromised patients in the surgery group., Conclusions: Total thyroidectomy could be considered the therapeutic choice for AIT patients with severe systolic dysfunction, whereas it is not superior to medical therapy in those with normal or mildly reduced LVEF., (© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Glial cells missing-2 (GCM2) is key for parathyroid gland organogenesis. Its persistent expression in the adult parathyroid raises the possibility that overactive forms play a role in the evolution of parathyroid hyperactivity or tumorigenesis. A GCM2 c.844T → G; p.Y282D missense variant has been described within a transactivation inhibitory domain (amino acids 263-352)., Objective: The aims of the study were to 1) assess the frequency of Y282D in Italian primary hyperparathyroidism (PHPT) and control (C) populations, 2) test for association of 282D with PHPT and its phenotypic features, and 3) compare the transactivation potency of GCM2 282D relative to wild-type Y282., Subjects and Methods: Subjects included a large southern Italian cohort (310 PHPT and 433 C) and 2 replication cohorts from northern Italy. Association of 282D with PHPT was tested in all cohorts and with phenotypic features in the larger PHPT cohort. An in vitro GCM promoter-luciferase reporter assay was conducted in HEK293 cells., Results: 282D was significantly increased in the PHPT group, with a minor allele frequency of 0.066 compared with 0.029 in the C group (P = .0008), in the discovery cohort and was more prevalent in the replication cohorts. Combined analysis (510 PHPT and 665 C) yielded a likelihood ratio of 2.27 (95% confidence interval = 1.50-3.42; P < .0001). The 282D variant was not associated with serum calcium, phosphate, creatinine, or PTH levels or with bone mineral density, fractures, or renal stones in the PHPT group. The 282D variant had significantly greater transcriptional activity than the wild-type Y282 (17× basal vs 12× basal; P < 0.05)., Conclusion: The higher frequency of GCM2 282D in PHPT and enhanced transcriptional activity of this variant supports the notion that it could contribute causally to parathyroid tumorigenesis.

Objective: Asymptomatic primary hyperparathyroidism (PHPT) is a common clinical problem. The only available definitive therapy is parathyroidectomy, which is appropriate to consider in all patients. The purpose of this report is to provide an update on calcium and vitamin D supplementation and medical management for those patients with PHPT who cannot or do not want to undergo surgery., Methods: Questions were developed by the International Task Force on PHPT. A comprehensive literature search was undertaken, and relevant articles published between 2008 and 2013 were reviewed in detail. The questions were addressed by the panel of experts, and consensus was established at the time of the workshop., Conclusions: The recommended calcium intake in patients with PHPT should follow guidelines established for all individuals. It is not recommended to limit calcium intake in patients with PHPT who do not undergo surgery. Patients with low serum 25-hydroxyvitamin D should be repleted with doses of vitamin D aiming to bring serum 25-hydroxyvitamin D levels to ≥ 50 nmol/L (20 ng/mL) at a minimum, but a goal of ≥75 nmol/L (30 ng/mL) also is reasonable. Pharmacological approaches are available and should be reserved for those patients in whom it is desirable to lower the serum calcium, increase BMD, or both. For the control of hypercalcemia, cinacalcet is the treatment of choice. Cinacalcet reduces serum calcium concentrations to normal in many cases, but has only a modest effect on serum PTH levels. However, bone mineral density (BMD) does not change. To improve BMD, bisphosphonate therapy is recommended. The best evidence is for the use of alendronate, which improves BMD at the lumbar spine without altering the serum calcium concentration. To reduce the serum calcium and improve BMD, combination therapy with both agents is reasonable, but strong evidence for the efficacy of that approach is lacking.

Objective: Asymptomatic primary hyperparathyroidism (PHPT) is routinely encountered in clinical practices of endocrinology throughout the world. This report distills an update of current information about diagnostics, clinical features, and management of this disease into a set of revised guidelines., Participants: Participants, representing an international constituency, with interest and expertise in various facets of asymptomatic PHPT constituted four Workshop Panels that developed key questions to be addressed. They then convened in an open 3-day conference September 19-21, 2013, in Florence, Italy, when a series of presentations and discussions addressed these questions. A smaller subcommittee, the Expert Panel, then met in closed session to reach an evidence-based consensus on how to address the questions and data that were aired in the open forum., Evidence: Preceding the conference, each question was addressed by a relevant, extensive literature search. All presentations and deliberations of the Workshop Panels and the Expert Panel were based upon the latest information gleaned from this literature search., Consensus Process: The expert panel considered all the evidence provided by the individual Workshop Panels and then came to consensus., Conclusion: In view of new findings since the last International Workshop on the Management of Asymptomatic PHPT, guidelines for management have been revised. The revised guidelines include: 1) recommendations for more extensive evaluation of the skeletal and renal systems; 2) skeletal and/or renal involvement as determined by further evaluation to become part of the guidelines for surgery; and 3) more specific guidelines for monitoring those who do not meet guidelines for parathyroid surgery. These guidelines should help endocrinologists and surgeons caring for patients with PHPT. A blueprint for future research is proposed to foster additional investigation into issues that remain uncertain or controversial.

Context: The molecular pathogenesis of primary hyperparathyroidism is still largely unknown. The aryl hydrocarbon receptor interacting protein (AIP) gene has a major role in the pathogenesis of familial isolated pituitary adenoma., Objective: We evaluated the involvement of the AIP gene in sporadic parathyroid adenomas., Patients and Design: We performed direct sequencing and multiplex ligation-dependent probe amplification analyses of the AIP gene in a large series of sporadic parathyroid adenomas. Loss of heterozygosity (LOH) at the AIP locus was studied, and aryl hydrocarbon receptor interacting protein immunostaining was also performed. In addition, alterations in the MEN1 gene were studied., Results: A somatic AIP mutation, substitution of arginine with glutamine at codon 304 (R304Q), was identified in 2 of 132 tumors. The mutation was germline in both cases despite the nonfamilial presentation. Heterozygous AIP large deletions were detected in 29 cases including 1 of the 2 mutated tumors, confirming a biallelic inactivation of the AIP gene. The AIP-mutated tumor with LOH showed decreased AIP immunostaining compared with normal parathyroid. LOH at the MEN1 locus, which often shared LOH at the AIP locus, was found in one third of tumors. Somatic MEN1 mutations were found in the 1 of the 2 AIP-mutated tumors and in 22 parathyroid adenomas. In addition, multiplex ligation-dependent probe amplification analysis revealed 1 large deletion of the MEN1 gene in 1 patient., Conclusions: The AIP gene is rarely involved in parathyroid adenomas, but the germline nature of the mutations suggests that it might predispose to primary hyperparathyroidism. MEN1 gene alterations occur in a substantial proportion of sporadic parathyroid adenomas.

Background: Optimal doses of i.v. glucocorticoids for Graves' orbitopathy (GO) are undefined., Methods: We carried out a multicenter, randomized, double-blind trial to determine efficacy and safety of three doses of i.v. methylprednisolone in 159 patients with moderate to severe and active GO. Patients were randomized to receive a cumulative dose of 2.25, 4.98, or 7.47 g in 12 weekly infusions. Efficacy was evaluated objectively at 12 wk by blinded ophthalmologists and subjectively by blinded patients (using a GO specific quality of life questionnaire). Adverse events were recorded at each visit., Results: Overall ophthalmic improvement was more common using 7.47 g (52%) than 4.98 g (35%; P = 0.03) or 2.25 g (28%; P = 0.01). Compared with lower doses, the high-dose regimen led to the most improvement in objective measurement of ocular motility and in the Clinical Activity Score. The Clinical Activity Score decreased in all groups and to the least extent with 2.25 g. Quality of life improved most in the 7.47-g group, although not reaching statistical significance. No significant differences occurred in exophthalmos, palpebral aperture, soft tissue changes, and subjective diplopia score. Dysthyroid optic neuropathy developed in several patients in all groups. Because of this, differences among the three groups were no longer apparent at the exploratory 24-wk visit. Major adverse events were slightly more frequent using the highest dose but occurred also using the lowest dose. Among patients whose GO improved at 12 wk, 33% in the 7.47-group, 21% in the 4.98-group, and 40% in the 2.25-group had relapsing orbitopathy after glucocorticoid withdrawal at the exploratory 24-wk visit., Conclusions: The 7.47-g dose provides short-term advantages over lower doses. However, this benefit is transient and associated with slightly greater toxicity. The use of a cumulative dose of 7.47 g of methylprednisolone provides short-term advantage over lower doses. This may suggest that an intermediate-dose regimen be used in most cases and the high-dose regimen be reserved to most severe cases of GO.

Context: In a previous study, we found that total thyroid ablation (thyroidectomy plus (131)I) is associated with a better outcome of Graves' orbitopathy (GO) compared with thyroidectomy alone, as observed shortly (9 months) after glucocorticoid (GC) treatment., Objective: The objective of the study was to evaluate the outcome of GO in the same patients of the previous study over a longer period of time., Design: This was a follow-up of a randomized study., Setting: The study was conducted at a referral center., Patients: Fifty-two of 60 original patients with mild to moderate GO participated in the study., Interventions: Patients randomized into thyroidectomy (TX) or total thyroid ablation and treated with GC were reevaluated in 2010, namely 88.0 ± 17.7 months after GC, having undergone an ophthalmological follow-up in the intermediate period., Main Outcome Measures: The main outcome measures included the following: 1) GO outcome; 2) time to GO best possible outcome and to GO improvement; and 3) additional treatments., Results: GO outcome at the end of the follow-up was similar in the two groups. However, the time required for the best possible outcome to be achieved was longer in the TX group (24 vs. 3 months, P = 0.0436), as was the time required for GO to improve (60 vs. 3 months, P = 0.0344). Additional treatments were given to a similar proportion of patients in each group (TX, 28%, total thyroid ablation, 25.9%), but they affected GO beneficially more often in the TX group (28 vs. 3.7%, P: 0.0412)., Conclusions: Compared with thyroidectomy alone, total thyroid ablation allows the achievement of the best possible outcome and an improvement of GO within a shorter period of time.

Objective: The aim of this study was to assess whether patients with primary hyperparathyroidism (PHPT) show reduced endothelial function and to determine the mechanisms involved. The impact of parathyroidectomy (PTx) on endothelial function was also assessed., Background: Endothelial dysfunction is reported in patients with PHPT, but the mechanisms involved are unknown., Methods: We evaluated forearm blood flow changes (strain gauge plethysmography) induced by intraarterial acetylcholine or sodium nitroprusside in 17 PHPT women and 17 age-matched controls. Nitric oxide (NO) availability and oxidative stress were studied by repeating acetylcholine during intraarterial infusion of L-N(G)-monomethyl arginine (L-NMMA, a NO synthase inhibitor) and ascorbic acid (an oxidative stress scavenger). The role of cytochrome P450 epoxygenase (CYP 2C9)-derived endothelium-derived hyperpolarizing factor (EDHF) was assessed by repeating acetylcholine under intraarterial sulfaphenazole. In six PHPT patients, the study was repeated 12 months after successful PTx., Results: Responses to sodium nitroprusside and acetylcholine were similar in PHPT patients and controls. L-NMMA inhibited the response to acetylcholine in controls (P < 0.001), whereas it had no effect in PHPT patients. In both groups, ascorbic acid failed to affect acetylcholine. Sulfaphenazole administration, although not affecting vasodilation to acetylcholine in controls, blunted the response to acetylcholine in PHPT patients (P < 0.005). After PTx, the inhibitory effect of L-NMMA on acetylcholine was restored (P < 0.001), and the inhibitory effect of sulfaphenazole on acetylcholine was abrogated., Conclusions: PHPT patients show compromised NO availability, whereas oxidative stress generation is not involved. A compensatory CYP 2C9-derived EDHF pathway is activated to sustain endothelium-dependent vasodilation. This PHPT-related endothelial dysfunction is reversed after PTx.

Context: Patients with persistent primary hyperparathyroidism (PHPT) after parathyroidectomy or with contraindications to parathyroidectomy often require chronic treatment for hypercalcemia., Objective: The objective of the study was to assess the ability of the calcimimetic, cinacalcet, to reduce serum calcium in patients with intractable PHPT., Design: This was an open-label, single-arm study comprising a titration phase of variable duration (2-16 wk) and a maintenance phase of up to 136 wk., Setting: The study was conducted at 23 centers in Europe, the United States, and Canada., Patients: The study included 17 patients with intractable PHPT and serum calcium greater than 12.5 mg/dl (3.1 mmol/liter)., Intervention: During the titration phase, cinacalcet dosages were titrated every 2 wk (30 mg twice daily to 90 mg four times daily) for 16 wk until serum calcium was 10 mg/dl or less (2.5 mmol/liter). If serum calcium increased during the maintenance phase, additional increases in the cinacalcet dose were permitted., Main Outcome Measure: The primary end point was the proportion of patients experiencing a reduction in serum calcium of 1 mg/dl or greater (0.25 mmol/liter) at the end of the titration phase., Results: Mean +/- sd baseline serum calcium was 12.7 +/- 0.8 mg/dl (3.2 +/- 0.2 mmol/liter). At the end of titration, a 1 mg/dl or greater reduction in serum calcium was achieved in 15 patients (88%). Fifteen patients (88%) experienced treatment-related adverse events, none of which were serious. The most common adverse events were nausea, vomiting, and paresthesias., Conclusions: In patients with intractable PHPT, cinacalcet reduces serum calcium, is generally well tolerated, and has the potential to fulfill an unmet medical need.

Context: An increased risk of fracture in patients with primary hyperparathyroidism (PHPT) compared to the general population has been reported, but available data are controversial., Objective: The aim of the study was to evaluate the rate of vertebral fractures (VFs) by dual-energy x-ray absorptiometry in postmenopausal women with sporadic PHPT and compare the results with a control group., Design and Setting: A case-control study was performed at a referral center., Participants: A total of 150 consecutive patients and 300 healthy women matched for age and menopausal age participated in the study., Results: VFs were detected in 37 of 150 (24.6%) patients and 12 of 300 (4.0%) controls (P < 0.0001). The majority of VFs were mild. Stepwise multiple logistic regression analysis showed that in PHPT patients lumbar spine bone mineral density was the only variable independently associated with the prevalence of VFs (P = 0.003). The rate of fracture was higher in symptomatic (34.1%) than asymptomatic (21.1%) patients, but this difference was not statistically significant (P = 0.15). Among asymptomatic patients, fracture rate was significantly higher in those who met the criteria for parathyroidectomy (28.1%) than in those who did not (11.1%) (P = 0.03). Compared to controls, the fracture rate was significantly higher in patients with symptomatic and asymptomatic PHPT who met the criteria for surgery (P < 0.0001), but not in those who did not meet the criteria (P = 0.06)., Conclusions: VF rate is increased in postmenopausal women with PHPT compared to controls, independently of whether they are classified as symptomatic or asymptomatic. The question of whether the finding of mild morphometric VFs in the latter represents an indication for parathyroid surgery remains to be established.

Context: In autoimmune polyendocrinopathy syndrome type I (APS-I), mutations in the autoimmune regulator gene (AIRE) impair thymic self-tolerance induction in developing T cells. The ensuing autoimmunity particularly targets ectodermal and endocrine tissues, but chronic candidiasis usually comes first. We recently reported apparently APS-I-specific high-titer neutralizing autoantibodies against type I interferons in 100% of Finnish and Norwegian patients, mainly with two prevalent AIRE truncations., Objectives: Because variability in clinical features and age at onset in APS-I frequently results in unusual presentations, we prospectively checked the diagnostic potential of anti-interferon antibodies in additional APS-I panels with other truncations or rare missense mutations and in disease controls with chronic mucocutaneous candidiasis (CMC) but without either common AIRE mutation., Design: The study was designed to detect autoantibodies against interferon-alpha2 and interferon-omega in antiviral neutralization assays., Setting and Patients: Patients included 14 British/Irish, 15 Sardinian, and 10 Southern Italian AIRE-mutant patients with APS-I; also 19 other patients with CMC, including four families with cosegregating thyroid autoimmunity., Outcome: The diagnostic value of anti-interferon autoantibodies was assessed., Results: We found antibodies against interferon-alpha2 and/or interferon-omega in all 39 APS-I patients vs. zero of 48 unaffected relatives and zero of 19 British/Irish CMC patients. Especially against interferon-omega, titers were nearly always high, regardless of the exact APS-I phenotype/duration or AIRE genotype, including 12 different AIRE length variants or 10 point substitutions overall (n=174 total). Strikingly, in one family with few typical APS-I features, these antibodies cosegregated over three generations with autoimmune hypothyroidism plus a dominant-negative G228W AIRE substitution., Conclusions: Otherwise restricted to patients with thymoma and/or myasthenia gravis, these precocious persistent antibodies show 98% or higher sensitivity and APS-I specificity and are thus a simpler diagnostic option than detecting AIRE mutations.

Context: It is unclear whether patients with asymptomatic primary hyperparathyroidism (PHPT) do better with parathyroidectomy (PTx) as compared with conservative medical management., Objective: The aim of the study was to evaluate the beneficial effect of PTx vs. conservative management in patients with mild asymptomatic PHPT., Design: We conducted a prospective, randomized study., Setting: The study took place at a referral center., Patients: We studied 50 patients who did not meet any guidelines for parathyroid surgery as recommended by the National Institutes of Health Consensus Development Conference on Asymptomatic PHPT., Intervention: Patients were randomly assigned to PTx or no PTx and were evaluated at 6 months and at 1 yr., Main Outcome Measures: We compared changes (percentage of basal) of lumbar spine bone mineral density (BMD) between the two groups at 1 yr., Results: The change in BMD at lumbar spine was greater after PTx (+4.16 +/- 1.13 for PTx vs. -1.12 +/- 0.71 for no PTx; P = 0.0002). The change in BMD at the total hip was also significantly greater in the PTx group (+2.61 +/- 0.71 for PTx vs. -1.88 +/- 0.60 for no PTx; P = 0.0001). There was no difference in BMD after 1 yr between both groups at the one-third radius site. In comparison with those who did not undergo surgery, the PTx subjects, after 1 yr, showed significant differences in four quality of life measures as determined by the 36-item short form health survey scale: bodily pain (P = 0.001), general health (P = 0.008), vitality (P = 0.003), and mental health (P = 0.017)., Conclusions: In patients with mild asymptomatic PHPT, successful PTx is followed by an improvement in BMD and quality of life. Most patients followed without surgery did not show evidence of progression.

Context: Graves' orbitopathy (GO) is probably caused by autoimmune reactions against autoantigen(s) shared by thyroid and orbital tissues sustained by intrathyroidal autoreactive T-lymphocytes infiltrating the orbit. Total thyroid ablation (TTA) may be beneficial for GO through removal of shared antigen(s) and autoreactive T-lymphocytes, but randomized studies are lacking., Objective: Our objective was to evaluate the effects of TTA in patients with GO treated with iv glucocorticoids (GC)., Design/setting: A prospective, single-blind, randomized study was conducted at a referral center., Patients/interventions: Sixty patients with mild to moderate GO were randomized into: 1) near-total thyroidectomy (TX); or 2) TX plus (131)I (TTA) groups, and then treated with iv GC. Patients were evaluated 3 and 9 months after iv GC., Main Outcome Measure: Overall improvement of GO at 9 months was the main outcome measure., Results: The distribution of GO outcome at 9 months was significantly more favorable in TTA than in TX patients (P = 0.0014 by chi(2) test). A cumulative significant (P = 0.0054) difference between the two groups at 3 and 9 months was found using a generalized linear model. Radioiodine uptake test and thyroglobulin assay in a patient sample showed complete ablation in the majority of TTA, but not of TX patients., Conclusions: Compared with thyroidectomy alone, TTA is followed by a better outcome of GO in patients given iv GC. Whether TTA maintains this advantage in the long-term remains to be established.

We investigated the involvement of the HRPT2 gene by loss of heterozygosity analysis and direct sequencing in a kindred with hyperparathyroidism-jaw tumor syndrome (HPT-JT) and three kindreds with familial isolated primary hyperparathyroidism (FIHP). Seven patients with sporadic parathyroid cancers and 35 with parathyroid adenomas with no family history of primary hyperparathyroidism or HPT-JT were also studied. A germline heterozygous substitution G to A was found in the donor splice site of intron 1 in one of the three FIHP families. No mutations were identified in the HPT-JT kindred. A somatic HRPT2 mutation was found in four of seven patients with parathyroid cancers, two of which were unreported frameshift mutations (195insT and 195insA) in exon 2. Consistent with recent findings, two of seven patients with sporadic parathyroid cancer had germline mutations. Four adenomas showed loss of heterozygosity at HRPT2, whereas a somatic HRPT2 mutation was found in one. In conclusion, we provide additional evidence for a strong association between HRPT2 gene mutations and sporadic parathyroid cancer. The finding that two of the seven patients with sporadic parathyroid cancer carried an HRPT2 germline mutation suggests that they might have occult HPT-JT. Our results also confirm the need for testing HRPT2 gene in FIHP families.

GH secretion is impaired in most patients with primary hyperparathyroidism (PHP), although the secretion of the other anterior pituitary hormones is unaffected. However, whether restoration of euparathyroidism is associated with reversal of GH deficiency in PHP patients is not known. To address this issue, we studied 30 consecutive patients with PHP due to a single parathyroid adenoma before and after parathyroidectomy. GH secretion was evaluated by peak serum GH after the maximal GHRH + arginine (Arg) stimulation test. A group of 35 age- and sex-matched normal subjects served as controls. Serum IGF-I concentration was below the normal age- corrected values in six of 30 patients before surgery and in four of 30 patients after parathyroidectomy (P = not significant). Mean serum peak GH values after the GHRH + Arg test were 17.5 +/- 2.8 micro g/liter before surgery and 23.8 +/- 2.5 micro g /liter after surgery (P = 0.0008). The GH response to the GHRH + Arg test was reduced in 20 (67%) and normal in 10 (33%) of 30 PHP patients at baseline; after surgery, 22 of 30 (73%) PHP patients had a normal GH response to the GHRH + Arg test, and only eight (27%) had an impaired GH secretion (P < 0.02). In conclusion, this study confirms that GH secretion is impaired in PHP patients and indicates that it is reversed in many patients after parathyroidectomy. Accordingly, GH deficiency in PHP patients must be considered a functional phenomenon for which GH therapy is not recommended.

We describe a 45-yr-old woman with metastatic breast cancer and hypercalcemia previously diagnosed as hypercalcemia of malignancy and treated with bisphosphonates without changes of serum calcium (s-Ca). At the time of our evaluation, biochemical data [s-Ca, 10.8 mg/dl (2.70 mmol/liter); PTH, 24.4 pg/ml (2.6 pmol/liter); 24-h urinary calcium, 160 mg (4.0 mmol); calcium/creatinine clearance, 0.007] suggested the diagnosis of familial hypocalciuric hypercalcemia. Three of five relatives had mild hypercalcemia [s-Ca, 10.7-11.2 mg/dl (2.67-2.80 mmol/liter)] and detectable serum PTH [24.5-29.0 pg/ml (2.6-3.1 pmol/liter)]. A novel heterozygous I212T missense mutation in exon 4 of the calcium-sensing receptor (CaR) gene was found in the proband and affected relatives but not in unaffected relatives. Expression of the mutant I212T CaR in COS-7 cells resulted in no response of inositol phosphates to any calcium concentration. The calcium dose-response curve of the coexpressed receptors [wild-type/I212T] suggested that the mutant receptor interferes with the function of the wild-type receptor. In conclusion, we describe a case of familial hypocalciuric hypercalcemia due to a novel CaR mutation, in a woman with breast cancer in whom hypercalcemia was initially attributed to hypercalcemia of malignancy.

We investigated the long-term side-effects of orbital radiotherapy (OR) in 204 patients with Graves' ophthalmopathy (GO), irradiated from 1972-1996 [44 by cobalt unit (CU) and 160 by linear accelerator (LA), mostly combined with glucocorticoids], with a 5- to 25-yr follow-up (median, 11 yr). Cataract was observed in 21 patients (10%) 3-21 yr after OR, with a higher (not significant) prevalence in CU-treated patients (18% vs. 8% in LA-treated patients). The prevalence of cataract was higher, although not significantly, in CU-treated patients aged less than 60 yr, but not in LA-treated patients, compared with the general population. Mild, asymptomatic retinopathy was observed in 1 of 7 patients (14%) with diabetes and hypertension, in 1 of 31 patients (3%) with hypertension alone, and in 0 of 11 patients with diabetes alone. No tumors were observed in 157 patients submitted to computed tomography scan of orbital and adjacent regions. In conclusion, OR is a safe treatment, not associated with an increased frequency of cataract, provided a high voltage apparatus is used. Hypertension, especially if associated with diabetes, may represent a relative contraindication, as it may cause retinopathy. Although no secondary tumors were detected, due to the long latency of radiation-induced tumors, OR should be restricted to patients older than 35 yr.

The activity of the GH/IGF-I axis as a function of parathyroid activity and calcium metabolism in humans has never been assessed. To address this issue, we studied 18 patients (5 men, 13 women; age range, 23-76 yr; mean, 61 yr) with primary hyperparathyroidism (PHP) due to solitary parathyroid adenoma. GH secretion was evaluated by serum IGF-I levels, spontaneous mean GH secretion over two morning hours, and GH response to arginine (ARG) alone or combined with GHRH. In five patients, serum GH concentrations were measured every 20 min for 24 h, and deconvolution analysis was performed. A group of 35 age- and sex-matched normal subjects served as controls. Mean serum IGF-I levels in PHP were lower than in normal controls, and in six PHP patients individual serum IGF-I levels were below the age-related normal range. The mean (+/-SE) peak GH response to ARG alone in PHP patients was significantly lower than in normal subjects (4.0 +/- 1.0 vs. 22.0 +/- 1.3 microg/liter; P < 0.001). Likewise, the mean (+/-SE) peak GH response to ARG plus GHRH was reduced in PHP patients (9.9 +/- 0.9 vs. 38.0 +/- 3.5 microg/liter; P < 0.001). The mean GH concentration over two morning hours in PHP was lower (0.20 +/- 0.05 vs. 1.34 +/- 0.31 microg/liter; P < 0.001). The mean GH concentration over 24 h in five PHP patients was lower than in six normal controls (0.3 +/- 0.1 vs. 0.7+/- 0.1 microg/liter; P < 0.05); the deconvolution analysis showed that 24-h GH production rate (3.0 +/- 1.7 vs. 28.2 +/- 4.7 microg/liter.d; P < 0.05) and mean secretory burst mass (1.2 +/- 0.7 vs. 10.5 +/- 2.6 microg/liter; P < 0.05), but not pulse frequency, were lower in PHP patients than in normal controls. GH half-life and approximate entropy values of 24-h GH profiles were similar in PHP patients and normal controls. No correlation was found between serum-ionized calcium or PTH levels and spontaneous or stimulated GH levels in PHP patients. In conclusion, this study demonstrates that PHP patients have a reduction in both spontaneous and stimulated GH secretion. Accordingly, PHP should be mentioned as a further example of a metabolic condition in which GH secretion in adults is reduced.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy is a rare autosomal recessive disorder characterized by hypoparathyroidism, adrenal failure, chronic mucocutaneous candidiasis, and ectodermal dystrophies and other organ-specific autoimmune diseases. Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy is caused by mutations of the autoimmune regulator gene. We identified an Italian family with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy and a pattern of inheritance suggestive of a dominant mechanism. Serological and clinical studies showed a high prevalence of hypothyroid autoimmune thyroiditis in affected members with classical autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy. Direct sequencing of the entire coding region of the autoimmune regulator gene revealed the presence in the proband of a novel missense (G228W) mutation in exon 6 in a heterozygous state. The same heterozygous mutation was identified in all family members with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy and/or hypothyroid autoimmune thyroiditis. None of the unaffected family members and 50 unrelated Italian controls carried the mutation. In contrast with all other autoimmune regulator mutations reported in families, the novel G228W mutation acts in a dominant fashion in our family, as only one heterozygous mutation was found in the entire coding sequence of the autoimmune regulator gene in the proband. Moreover, analysis of the family tree showed direct transmission of the hypothyroid autoimmune thyroiditis/polyendocrinopathy-candidiasis-ectodermal dystrophy phenotype to the offspring in each generation in the absence of consanguinity, further supporting a dominant inheritance. The G228W closely cosegregated with hypothyroid autoimmune thyroiditis in our family, whereas a low penetrance of the full autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy phenotype was observed. In conclusion, we report a novel mutation of the autoimmune regulator gene in a family with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, closely cosegregating with hypothyroid autoimmune thyroiditis. The G228W mutation acts in a dominant fashion and may shed light on the structure-function relationship of the autoimmune regulator protein.

Eighty-two consecutive patients with moderate-to-severe and active Graves' ophthalmopathy were randomly treated with orbital radiotherapy combined with either oral (prednisone; starting dose, 100 mg/d; withdrawal after 5 months) or iv (methylprednisolone; 15 mg/kg for four cycles and then 7.5 mg/kg for four cycles; each cycle consisted of two infusions on alternate days at 2-wk intervals) glucocorticoids. The two groups did not differ for age, gender, duration of hyperthyroidism and ophthalmopathy, prevalence of smokers, thyroid volume, and pretreatment ocular conditions. Both groups of patients received radioiodine therapy shortly before treatment for Graves' ophthalmopathy. Follow-up lasted for 12 months. A significant reduction in proptosis (from 23.2 +/- 3.0 to 21.6 +/- 1.2 mm in the iv glucocorticoid group, P < 0.0001; and from 23 +/- 1.8 to 21.7 +/- 1.8 mm in oral glucocorticoid group, P < 0.0001) and in lid width (from 13.3 +/- 2.5 to 11.8 +/- 2.2 mm, and from 13.6 +/- 2.0 to 11.5 +/- 1.9 mm, respectively; P < 0.001 in both cases) occurred, with no difference between the two groups. Diplopia significantly improved in both groups: it disappeared in 13 of 27 (48.1%) iv glucocorticoid patients (P < 0.005) and in 12 of 33 (36.4%) oral glucocorticoid patients (P < 0.03). The degree of amelioration of diplopia did not significantly differ between the two groups (P = 0.82). Optic neuropathy improved in 11 of 14 iv glucocorticoid (P < 0.01) and only in 3 of 9 oral glucocorticoid (P = 0.57) patients, with no significant difference in these outcomes. The Clinical Activity Score decreased from 4.5 +/- 1.2 to 1.7 +/- 1.0 (P < 0.0001) in the iv glucocorticoid group and from 4.2 +/- 1.1 to 2.2 +/- 1.2 (P < 0.0001) in the oral glucocorticoid group; final Clinical Activity Score was significantly lower in iv glucocorticoid than in oral glucocorticoid patients (P < 0.01). By self-assessment evaluation, 35 (85.3%) iv glucocorticoid and 30 (73.2%) oral glucocorticoid patients reported an improvement of ocular conditions (P = 0.27). Overall, both treatments produced favorable effects in most patients, but responders in the iv glucocorticoid group (36 of 41, 87.8%) were more than in the oral glucocorticoid group (26 of 41, 63.4%) (P < 0.02). Moreover, iv glucocorticoid treatment was better tolerated than oral glucocorticoid treatment. Side effects occurred in 23 (56.1%) iv glucocorticoid and 35 (85.4%) oral glucocorticoid patients (P < 0.01); in particular, cushingoid features developed in 5 of the former and 35 of the latter patients. One iv glucocorticoid patient had severe hepatitis of undetermined origin at the end of glucocorticoid treatment, followed by spontaneous recovery. In conclusion, high-dose iv glucocorticoid and oral glucocorticoid (associated with orbital radiotherapy) are effective in the management of severe Graves' ophthalmopathy, but the iv route seems to be more effective and better tolerated than the oral route and associated with a lower rate of side effects.

A reduced expression of calcium-sensing receptor (CaR) messenger ribonucleic acid and protein accompanied by abnormalities in parathyroid cell proliferation and PTH secretion are present in primary hyperparathyroidism. We studied the expression of CaR protein by immunohistochemistry in 36 sporadic parathyroid adenomas and investigated the relationship between CaR expression and several preoperative clinical parameters, including the set-point of Ca(2+)-regulated PTH secretion (measured in vivo). The adenomas were classified in 4 categories according to the intensity of immunohistochemical staining: 5 (14%) showed a CaR staining intensity similar to that of normal parathyroid ( ), 10 (27%) showed moderate staining (++), 16 (45%) showed weak staining (+), and 5 (14%) were negative (-). The intensity of CaR staining was not related to preoperative serum Ca(2+), PTH levels or adenoma volume. Twenty-nine patients underwent preoperatively the calcium infusion test to evaluate the PTH-Ca(2+) set-point. Individual values of PTH-Ca(2+) set-point ranged from 1.38-1.93 mmol/L and were significantly correlated with basal Ca(2+) levels (r = 0.96; P: = 0. 0001) and adenoma volume (r = 0.5; P: = 0.01). The mean PTH-Ca(2+) set-point values were significantly different in the 4 groups of patients classified according to immunohistochemical staining intensity of their adenoma (P: = 0.025; F = 3.78); the mean PTH-Ca(2+) set-point was significantly higher in the groups classified as negative than in those classified as weak or moderate. No correlation was observed between the PTH-Ca(2+) set-point and basal PTH levels or between the percent maximal PTH inhibition and adenoma volume and basal PTH or Ca(2+) levels. In summary, our data suggest that there is a relationship between apparent CaR protein expression and PTH-Ca(2+) set-point abnormality, suggesting that a reduced receptor content might have an important role in the pathogenesis of primary hyperparathyroidism.

A multiplicity of TSH receptor autoantibodies (TSHRAbs) have been characterized after subcloning heterohybridomas produced from the lymphocytes of a patient who has Hashimoto's thyroiditis and had three children with intrauterine or neonatal hyperthyroidism. Twelve clones produced stimulating TSHRAbs that increased cAMP levels and iodide uptake in rat FRTL-5 thyroid cells and increased cAMP levels in Chinese hamster ovary (CHO) cells transfected with the human TSHR; like 95% of Graves' stimulating TSHRAbs, all 12 have their functional epitope on the N-terminus of the TSHR extracellular domain, requiring residues 90-165 for activity. All 12 bind to human thyroid membranes in the absence, but not the presence, of TSH, but are only weak inhibitors of TSH binding in assays measuring TSH binding-inhibiting Igs (TBIIs). In contrast, 8 different clones produced TSHRAbs that did not increase cAMP levels, but, instead, exhibited significant TBII activity. Four inhibited the ability of TSH or a stimulating TSHRAb to increase cAMP levels and had their functional epitope on the C-terminal portion of the TSHR external domain, residues 261-370, mimicking the properties of blocking TSHRAbs that cause hypothyroidism in patients with idiopathic myxedema. The 4 other TBIIs inhibited the ability of TSH, but not that of a stimulating TSHRAb, to increase cAMP levels, like TBIIs in Graves' patients. The functional epitope for 3 of these Graves'-like TBIIs was residues 90-165; the functional epitope for the fourth was residues 24-89. The fourth also increased arachidonic acid release and inositol phosphate levels in FRTL-5 thyroid cells and exhibited conversion activity, i.e. the ability to increase cAMP levels in the presence of an anti-human IgG. Thus, this TBII exhibited signal transduction activity, unlike the other 3 Graves'-like TBIIs. The patient, therefore, has stimulating TSHRAbs and 3 different types of TBIIs, each with different functional properties and different epitopes on the TSHR.

Resistance to thyroid hormone (RTH), a syndrome characterized by variable tissue hyposensitivity to thyroid hormone, is linked to mutations in the thyroid hormone receptor-beta (TR beta) gene. The purpose of this study was to determine whether the clinical phenotypes of RTH can be translated in terms of functional impairment of the corresponding mutant TR beta. Data from 124 subjects with RTH representing 18 different mutant TR beta s, showed that serum free T4 levels correlated with the degree of T3-binding impairment of the corresponding TR beta in 12 of these mutant TR beta s (group I), but not in the remaining 6 (group II). In subjects from both groups studied in detail by the administration of incremental doses of T3, the degree of thyrotroph resistance to T3 correlated with the magnitude of endogenous free T4 elevation at baseline, but did not parallel the resistance of peripheral tissues. In transfection studies, all group I mutant TR beta s inhibited positive transactivation by the wild type TR beta s to a similar degree in the presence of 1 nmol/L T3, whereas group II mutant TR beta s exerted a weaker inhibition that was not related to their T3-dependent trans-activation when tested alone. Similar results were obtained with negatively regulated reporter genes. It is concluded that the clinical severity of RTH, determined by thyrotroph resistance, can be predicted from the degree of T3 binding impairment and dominant negative potency of mutant TR beta s, but the degree of peripheral tissue resistance and related clinical manifestations is limited by putative genetic or environmental factors that modulate the effect of thyroid hormone.

We measured total body and regional (lumbar spine, femoral neck, Ward's triangle, and trochanter) bone mineral density (BMD) in 47 premenopausal women chronically treated with suppressive doses of levothyroxine (L-T4). Treatment was administered to 7 patients with nontoxic goiter or, after thyroidectomy, to 38 patients with differentiated thyroid cancer and 2 with nontoxic goiter. Patients were followed at our institution and treated with the minimal amount of L-T4 necessary to suppress TSH. At the time of evaluation, free T3 was normal in all cases, whereas free T4 was increased in 17 (36.2%). The mean daily dose of L-T4 was 154.3 +/- 5 micrograms, and the mean duration of treatment was 10.1 yr. We found no significant difference between patients and age- and weight-matched controls in BMD at any site of measurement. BMD was not correlated with duration of therapy, cumulative or mean daily dose of L-T4, serum levels of free T4, free T3, and osteocalcin. There was no difference between patients and controls in serum total calcium, intact PTH, osteocalcin, or carboxy-terminal cross-linked telopeptide of type I collagen or in the concentrations of two markers of thyroid hormone action (sex hormone-binding globulin and amino-terminal propeptide of type III procollagen). Our data suggest that L-T4 suppressive therapy, if carefully carried out and monitored, using the smallest dose necessary to suppress TSH secretion has no significant effect on bone metabolism or bone mass.

Lymphocytic infiltration of muscular and connective tissues of the retroorbital (RO) space is a histological hallmark of Graves' ophthalmopathy (GO). We have characterized some phenotypical and functional features of T cells derived from RO infiltrates of four GO patients who were submitted to orbital decompression. Fragments of RO tissue were cultured for 7 days in IL-2-conditioned medium in order to generate T cell lines of in vivo activated T cells. Phenotypical analysis of freshly isolated peripheral blood (PB) lymphocytes both from patients and four healthy controls showed a predominance of CD4+ T cells (CD4/CD8 ratios 1.9:2.5), whereas RO-derived T cell lines displayed almost equal proportions of CD4+ and CD8+ cells (CD4/CD8 ratios 0.9:1.2). RO T cell lines and PB T cells from patients and controls were then cloned using a high-efficiency cloning procedure. The phenotypical and functional features of 153 T cell clones (TCC) derived from RO infiltrates were examined and compared with those of 166 and 236 TCC derived from the PB of patients and controls, respectively. CD4/CD8 ratios ranged from 0.8-1.4 in the series of RO-derived TCC and from 1.9-2.2 in the corresponding series of PB-derived TCC. Assessment of lectin-dependent cytolytic activity showed similar proportions of cytotoxic clones in TCC derived from the PB of patients (37%) and controls (38%); most of the cytolytic TCC was CD8+. In contrast, the proportion of cytolytic RO TCC was markedly higher (106/153 = 69%), including 100% of CD8+ and the majority (59/79 = 75%) of CD4+ clones. When compared to TCC derived from the PB of both patients and controls, RO TCC showed remarkably high proportions of both CD8+ and CD4+ clones with a Th1-like cytokine profile, as documented by their ability to secrete IL-2, IFN-gamma, and tumor necrosis factor-alpha (TNF-alpha), but not IL-4 or IL-5. This study provides evidence that cytolytic T cells with Th1 profile of cytokine production predominate in RO infiltrates of GO, a pattern quite similar to those previously described in thyroid infiltrates of Hashimoto's thyroiditis or Graves' disease. The peculiar cytokine secretion profile of RO T cells may be of importance in the pathogenesis of both the tissue alterations and fibrogenic process observed in GO.

Generalized resistance to thyroid hormone (GRTH), a syndrome of inherited tissue hyposensitivity to thyroid hormone, is linked to thyroid hormone receptor (TR) mutations. A typical feature of GRTH is variable severity of organ involvement among families that, surprisingly, does not correlate with the degree of T3-binding impairment of the corresponding in vitro synthesized mutant TRs. Furthermore, variations in the clinical severity among family members harboring identical TR beta mutations have been reported. We compared serum levels of thyroid hormones that maintained a normal TSH in members of a large family with GRTH divided in three groups: Group A, 8 affected subjects with a mutation replacing arginine-320 with a histidine in the T3-binding domain of TR beta; Group B, 11 first degree relatives (sibs and children of affected subjects) with no TR beta mutation; Group C, 16 controls related by marriage. TSH values were not different among the three groups. As expected, total and free T4 and T3, and rT3 levels were significantly higher in Group A vs Groups B and C. However, with the exception of T3, the same tests were also significantly higher in Group B vs Group C. The latter differences are not due to thyroid hormone transport in serum since TBG concentrations were not different. It is postulated that genetic variability of factors that contribute to the action of thyroid hormone modulate the phenotype of GRTH associated with TR beta mutations.

The clinical usefulness of thyroid ultrasonography in the evaluation of patients with autoimmune thyroiditis has been investigated. Thyroid ultrasonography was performed in 1184 consecutive patients attending our clinic, and the echo density of the thyroid parenchyma was evaluated with respect to that of normal thyroid tissue. Diffuse thyroid hypoechogenicity was found in 44 of 238 (18.5%) patients with autoimmune thyroiditis; the degree of hypoechogenicity was significantly correlated with the levels of circulating thyroid autoantibodies. Thyroid function was normal in all 194 patients with normal thyroid echogenicity, whereas hypothyroidism was found in 28 of 44 (63.6%) with reduced thyroid echogenicity. Included in this group were 8 patients, euthyroid at the first observation, who developed hypothyroidism over an 18-month follow-up period. None of the 133 patients with autoimmune thyroiditis and normal thyroid echogenicity followed for the same period of time became hypothyroid. Evidence of diffuse lymphocytic thyroiditis was obtained by histology after thyroidectomy (n = 10) or multiple fine needle aspiration cytology (n = 15) in 25 of the 44 patients with thyroid hypoechogenicity; on the other hand, focal thyroiditis was shown at histology in 8 patients who had normal thyroid echogenicity. In conclusion, diffuse low thyroid echogenicity was found in about 20% of patients with autoimmune thyroiditis. This echographic pattern is indicative of diffuse autoimmune involvement of the gland and is associated with or may predict the development of hypothyroidism.

The differential diagnosis of the various forms of inappropriate secretion of TSH (IST), i.e. generalized thyroid hormone resistance (GRTH), selective pituitary resistance [non-neoplastic IST (nnIST)], and tumoral pituitary TSH hypersecretion [neoplastic IST (nIST)], mainly rests on clinical observation, skull imaging, and measurement of several parameters assessing peripheral thyroid hormone effects. Clinically, patients with GRTH usually display compensated hypothyroidism, while those with nnIST or nIST are hyperthyroid. Since sex hormone-binding globulin (SHBG) measurement has been shown to be a reliable parameter in distinguishing between euthyroid and hyperthyroid states, we evaluated serum SHBG levels in 39 patients with IST (7 with GRTH, 15 with nnIST, and 17 with nIST). The results were compared to those in 68 normal subjects, 76 hyperthyroid patients, and 31 hypothyroid patients. SHBG levels in patients with either GRTH or nnIST were similar to those in controls or hypothyroid patients [GRTH, 40.5 +/- 11.8 (+/- SD) nmol/L (range, 26.4-57.5); nnIST, 29.7 +/- 12.8 nmol/L (range, 6.8-46.8); controls, 36.7 +/- 21.7 nmol/L (range, 5.4-96.5); hypothyroid, 30.8 +/- 14.4 nmol/L (range, 10.4-63.3)]. On the contrary, SHBG levels in patients with either overt hyperthyroidism or nIST were significantly higher than those in the above groups [hyperthyroid, 149 +/- 111 nmol/L (range, 48-557); nIST, 99.5 +/- 54.7 nmol/L (range, 21.6-259)]. The apparent overlap of SHBG values between hyperthyroid patients and controls almost completely disappeared when comparisons were made with control groups matched for age and sex. Additional indices of peripheral thyroid hormone action (basal metabolic rate, cardiac systolic time intervals, and Achilles' reflex time) were normal in patients with GRTH, while they were in the hyperthyroid range in patients with nnIST and nIST. After successful treatment of hyperthyroidism, SHBG levels normalized in patients with nIST, but they did not change in patients with nnIST. In conclusion, the measurement of SHBG in patients with IST is useful in differentiating the neoplastic form from that due to thyroid hormone resistance, but it fails to distinguish between generalized and pituitary resistance to thyroid hormone action. Moreover, the present data suggest that the resistance to thyroid hormone action in patients with nnIST is not selective at the thyrotroph cell level, but also involves the hepatic SHBG-synthesizing cells, thus supporting the view that the various forms of thyroid hormone resistance could represent a continuum of the same defect with variable expression in different tissues.

The ability of detergents (Triton X-100 and deoxycholate), high ionic strength solution (3 M KC1), and proteolytic enzymes (papain and trypsin) to solubilize human thyroid microsomal antigen was studied. Antigenic activity released from thyroid microsomal preparation into the incubation mixture was separated by centrifugation at 143,000 x g for 90 min and measured using 125I-labeled human immunoglobulin G (IgG) with elevated antimicrosomal (anti-M) and undetectable anti-thyroglobulin antibodies (anti-M IgG). All solubilized materials were shown to bind [125I]anti-M IgG and to inhibit its binding to untreated thyroid microsomes. These effects were specific and dose related. Measurements of specific activity and total amount of solubilized antigen by an absorption technique showed that Triton X-100 was the most effective agent, followed by deoxycholate, papain, trypsin, and 3 M KC1 in decreasing order. Affinity chromatography with the deoxycholate-solubilized material coupled to Sepharose 4B resulted in a 15.6-fold purification of [125I]anti-M antibodies. The present results indicate that thyroid microsomal antigen may be solubilized by several agents and this can provide the basis for its identification and purification.