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Hypercalcemic crisis is a severe but rare complication of primary hyperparathyroidism (PHPT), and data on denosumab treatment of patients with this disease is still very limited. The aim of this paper is to investigate the hypocalcemic effect of denosumab in PHPT patients with severe hypercalcemia when surgery should be delayed or is impossible for some reasons. We performed a retrospective study of 10 patients. The analysis included the use of biochemical markers of calcium-phosphorus metabolism, which were followed after the administration of 60 mg of denosumab. The trend to calcium reduction was already determined on the 3rd day after denosumab administration. In most cases the decrease in serum calcium level to the range of 2.8 mmol/L on average or lower was observed on the 7th day (P = 0.002). In addition to a significant increase in calcium levels we confirmed a significant increase in the estimated glomerular filtration rate on 7th day (P = 0.012). After that, seven patients underwent successful parathyroidectomy and achieved eucalcemia or hypocalcemia, one patient developed the recurrence of parathyroid cancer after initial surgery, while two patients with severe cardiovascular pathology refused surgery. Our study shows that denosumab is a useful tool in PHPT-associated hypercalcemia before surgery or if surgery is contraindicated.
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The first adjunctive hormone therapy for chronic hypoparathyroidism, recombinant human parathyroid hormone (1–84) (rhPTH(1–84)) was approved by the FDA in January 2015. Since the approval of rhPTH(1–84), growing interest has developed in other agents to treat this disorder in both the scientific community and among pharmaceutical companies. For several reasons, conventional therapy with calcium and activated vitamin D supplementation, magnesium supplementation as needed, and occasionally thiazide-type diuretic therapy remains the mainstay of treatment, while endocrinologists and patients are constantly challenged by limitations of conventional treatment. Serum calcium fluctuations, increased urinary calcium, hyperphosphatemia, and a constellation of symptoms that limit mental and physical functioning are frequently associated with conventional therapy. Understanding how conventional treatment and hormone therapy work in terms of pharmacokinetics and pharmacodynamics is key to effectively managing chronic hypoparathyroidism. Multiple questions remain regarding the effectiveness of PTH adjunctive therapy in preventing or slowing the onset and progression of the classical complications of hypoparathyroidism, such as chronic kidney disease, calcium-containing kidney stones, cataracts, or basal ganglia calcification. Several studies point toward an improvement in the quality of life during replacement therapy. This review will discuss current clinical and research challenges posed by treatment of chronic hypoparathyroidism.
Key points:
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Conventional therapy with calcium and activated forms of vitamin D are currently the mainstays of treatment for most patients with chronic hypoparathyroidism.
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Hormone therapy can be administered through FDA-approved once-daily rhPTH(1–84), or off-label multiple-daily injections of teriparatide. The former is the only FDA-approved drug, with safety and efficacy supported by a randomized placebo-controlled trial and open-label long-term extension trial data.
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Twice-daily teriparatide has been used in children safely for up to 10 years.
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New pharmacological options that replace the deficient hormone wi ll likely be available within the next few years.
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Abstract
GH and its principal mediator IGF1 have important effects on metabolic and cardiovascular (CV) status. While acquired GH deficiency (GHD) is often associated with increased CV risk, the consequences of congenital GHD are not known. We have described a large group of patients with isolated GHD (IGHD) due to a homozygous mutation (c.57+1G>A) in the GH releasing hormone receptor gene, and shown that adult GH-naïve individuals have no evidence of clinically evident premature atherosclerosis. To test whether subclinical atherosclerosis is anticipated in untreated IGHD, we performed a cross-sectional study of 25 IGHD and 27 adult controls matched for age and gender. A comprehensive clinical and biochemical panel and coronary artery calcium scores were evaluated by multi-detector tomography. Height, weight, IGF1, homeostasis model assessment of insulin resistance, creatinine and creatininekinase were lower in the IGHD group. Median and interquartile range of calcium scores distribution was similar in the two groups: IGHD 0(0) and control 0(4.9). The vast majority of the calcium scores (20 of 25 IGHD (80%) and 18 of 27 controls (66.6%)) were equal to zero (difference not significant). There was no difference in the calcium scores classification. None of IGHD subjects had minimal calcification, which were present in four controls. Three IGHD and four controls had mild calcification. There were two IGHD individuals with moderate calcification and one control with severe calcification. Our study provides evidence that subjects with congenital isolated lifetime and untreated severe IGHD do not have accelerated subclinical coronary atherosclerosis.
Regenerative Medicine Institute at CÚRAM SFI Research Centre, School of Medicine, National University of Ireland Galway (NUIG), Galway, Ireland
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Department of Clinical Biochemistry, SUHCG, GUH, Galway, Ireland
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Lambe Institute for Translational Research, School of Medicine, NUIG, Galway, Ireland
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Regenerative Medicine Institute at CÚRAM SFI Research Centre, School of Medicine, National University of Ireland Galway (NUIG), Galway, Ireland
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Newcastle upon Tyne NHS Hospitals Foundation Trust, Newcastle upon Tyne, UK
NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, UK
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Introduction
Inactivating mutations in CYP24A1, encoding vitamin D-24-hydroxylase, can lead to an accumulation of active vitamin D metabolites and consequent hypercalcaemia. Patient (infantile and adult) presentation is varied and includes mild-severe hypercalcaemia, hypercalciuria, nephrocalcinosis and nephrolithiasis. This study aimed to characterize the clinical and biochemical phenotypes of a family with two CYP24A1 missense variants.
Methods
The proband and seven family members underwent detailed clinical and biochemical evaluation. Laboratory measurements included serum calcium, intact parathyroid hormone (iPTH), vitamin D metabolites and urine calcium and creatinine.
Results
The proband presented during the second trimester of a planned pregnancy with flu-like symptoms. Laboratory tests showed elevated adjusted calcium of 3.27 (upper reference limit (URL: 2.30) mmol/L), suppressed iPTH (<6 ng/L), elevated 25(OH)D (264 (URL: 55) nmol/L) and elevated 1,25(OH)D (293 (URL: <280) pmol/L). Ionized calcium was 1.55 (URL: 1.28) mmol/L. Sanger sequencing revealed two heterozygous missense variants in the CYP24A1: p.(Arg439Cys), R439C and p.(Trp275Arg), W275R. The proband’s brother and sister had the same genotype. The brother had intermittent hypercalcaemia and hypervitaminosis D. Only the sister had a history of nephrolithiasis. The proband’s daughter and two nephews were heterozygous for the R439C variant. The proband and her brother frequently had elevated 25(OH)D:24,25(OH)2D ratios (>50) during follow-up.
Conclusions
W275R is a new pathogenic CYP24A1 mutation in compound heterozygotic form with R439C in this family.
Centre de Référence des Maladies Rares du Calcium et du Phosphore Filière de Santé Maladies Rares OSCAR, Paris, France
Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, INSERM, UMRS1138, Paris, France
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Université Paris-Saclay, Inserm U1185, Physiologie et Physiopathologie Endocriniennes, Assistance Publique-Hôpitaux de Paris, Service d’Endocrinologie et Diabète de l’Enfant, Centre de Référence des Maladies Rares du Calcium et du Phosphore et Filière de Santé Maladies Rares OSCAR, Hôpital Bicêtre Paris Saclay, Le Kremlin-Bicêtre, France
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Centre de Référence des Maladies Rares du Calcium et du Phosphore Filière de Santé Maladies Rares OSCAR, Paris, France
Assistance Publique-Hôpitaux de Paris, Institut Necker-Enfants Malades, INSERM U1151 – CNRS UMR 8253, Paris, France
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Association Francophone de Chirurgie Endocrinienne (AFCE), France
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Assistance Publique-Hôpitaux de Paris, Hôpital Cochin, Biochimie et Génétique Moléculaires, Paris, France
INSERM, U1169, Université Paris Sud, Hôpital Bicêtre, Le Kremlin Bicêtre, France
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INSERM, U1418, CIC-EC, Hôpital Européen Georges Pompidou, Paris, France
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Centre de Référence des Maladies Rares du Calcium et du Phosphore Filière de Santé Maladies Rares OSCAR, Paris, France
Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, INSERM, UMRS1138, Paris, France
CNRS, ERL8228, Paris, France
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Context
Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians’ practices or their adherence to such guidelines.
Objective
To describe the physicians’ practice patterns and their compliance with international guidelines.
Design
The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019).
Methods
Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients).
Results
The physicians’ specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion.
Conclusions
The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.
Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Department of Respiratory Medicine and Allergology, Sahlgrenska University Hospital, Gothenburg, Sweden
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Section for Endocrinology, Department of Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
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Section for Endocrinology, Department of Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
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Endocrine Out-Patient Clinic, Carlanderska Hospital, Gothenburg, Sweden
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Objective
Hypoparathyroidism (HypoPT) is a rare endocrine disorder in which insufficient levels of parathyroid hormone (PTH) lead to low serum calcium (S-Ca) levels and muscular cramps. The aim was to study the health-related quality of life (HRQoL) and comorbidities in patients with HypoPT compared with the general population and to estimate the need of treatment with PTH analog.
Design
Patients with HypoPT were identified and compared with a population sample. Short Form-36 (SF-36) and EuroQol-5 Dimensions Visual Analogue Scale questionnaires were used. All patients were followed up at the Sahlgrenska University Hospital outpatient clinic.
Methods
From the medical records between 2007 and 2020, 203 patients with HypoPT were identified and compared with a population sample (n = 414) from the World Health Organization’s (WHO) MONICA project, Gothenburg, Sweden. Of the 203 patients who met the diagnostic criteria, 164 were alive and 65% answered the HRQoL questionnaires.
Results
Patients with HypoPT, 80% postsurgical, and controls had similar age (60 years) and sex distribution (80% women). Patients had lower SF-36 summary component scores for physical (40.0 (interquartile range (IQR): 21) vs 51.2 (IQR: 14.6); P < 0.001) and mental (43.1 (IQR:17.4) vs 56.1(IQR:13.3); P < 0.001) well-being, irrespective of etiology or calcium levels. Individuals with HypoPT had more medications and lower renal function but not higher mortality than controls. Low HRQoL together with low calcium was present in 23% of individuals with HypoPT.
Conclusion
HRQoL was markedly lower in patients with HypoPT than in controls and independent of S-Ca levels. Treatment with PTH analog could be considered at least among patients with both low HRQoL and low calcium levels.
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Hypoparathyroidism and pseudohypoparathyroidism are rare endocrine disorders, characterized by low serum calcium due to inappropriate parathyroid hormone (PTH) levels or resistance to its action. There is little epidemiological information regarding chronic hypoparathyroidism in Russia. This study aims to build a registry database of Russian patients with chronic hypoparathyroidism who were referred for hospital treatment in order to conduct initial analysis of clinical presentations and hospital management. The Italian registry model was taken to be able to integrate our data in the future. Two hundred patients with hypoparathyroidism (n = 194) and pseudohypoparathyroidism (n = 6) were enrolled over 2 years (2017–2019). The most frequent cause of hypoparathyroidism was neck surgery (82.5%, mostly females), followed by idiopathic hypoparathyroidism (10%), syndromic forms of genetic hypoparathyroidism (4.5%) and forms of defective PTH action (3%). Calcium supplements and alfacalcidol were prescribed in most cases. However, a minority of patients (n = 6) needed to receive teriparatide as the only way to maintain calcium levels and to prevent symptoms of hypocalcemia. Consequently, substitution treatment with parathyroid hormone should be available in certain cases of hypoparathyroidism. This database will be useful to estimate the potential requirement for recombinant PTH in Russia and standards for clinical and therapeutic approaches.
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The role of G protein-coupled estrogen receptor 1 (GPER) signaling, including promotion of Ezrin phosphorylation (which could be activated by estrogen), has not yet been clearly identified in triple-negative breast cancer (TNBC). This study aimed to evaluate the prognostic value of GPER and Ezrin in TNBC patients. Clinicopathologic features including age, menopausal status, tumor size, nuclear grade, lymph node metastasis, AJCC TNM stage, and ER, PR and HER-2 expression were evaluated from 249 TNBC cases. Immunohistochemical staining of GPER and Ezrin was performed on TNBC pathological sections. Kaplan–Meier analyses, as well as logistic regressive and Cox regression model tests were applied to evaluate the prognostic significance between different subgroups. Compared to the GPER-low group, the GPER-high group exhibited higher TNM staging (P = 0.021), more death (P < 0.001), relapse (P < 0.001) and distant events (P < 0.001). Kaplan–Meier analysis showed that GPER-high patients had a decreased OS (P < 0.001), PFS (P < 0.001), LRFS (P < 0.001) and DDFS (P < 0.001) than GPER-low patients. However, these differences in prognosis were not statistically significant in post-menopausal patients (OS, P = 0.8617; PFS, P = 0.1905; LRFS, P = 0.4378; DDFS, P = 0.2538). There was a significant positive correlation between GPER and Ezrin expression level (R = 0.508, P < 0.001) and the effect of Ezrin on survival prognosis corresponded with GPER. Moreover, a multivariable analysis confirmed that GPER and Ezrin level were both significantly associated with poor DDFS (HR: 0.346, 95% CI 0.182–0.658, P = 0.001; HR: 0.320, 95% CI 0.162–0.631, P = 0.001). Thus, overexpression of GPER and Ezrin may contribute to aggressive behavior and indicate unfavorable prognosis in TNBC; this may correspond to an individual’s estrogen levels.
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Department of Endocrinology, Sahlgrenska University Hospital, Gothenburg, Sweden
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Purpose
We aimed to investigate the association between SHBG and the homeostatic model assessment of insulin resistance (HOMA-Ir) in men and women in a prospective observational study.
Methods
The Vara-Skövde cohort is a random population of 2816 participants living in southwestern Sweden, aged 30–74. It was recruited between 2002 and 2005, and followed up in 2012–2014. After excluding participants on insulin therapy or hormone replacement therapy, 1193 individuals (649 men, 544 women) were included in the present study. Fasting blood samples were collected at both visits and stored in biobank. All participants were physically examined by a trained nurse. SHBG was measured with immunoassay technique. Linear regressions were computed to investigate the association between SHBG and HOMA-Ir both in cross-sectional and longitudinal analyses, adjusting for confounding factors.
Results
The mean follow-up time was 9.7 ± 1.4 years. Concentrations of SHBG were significantly inversely associated with log transformed HOMA-Ir in all groups with estimated standardized slopes (95% CI): men: −0.20 (−0.3;−0.1), premenopausal women: −0.26 (−0.4;−0.2), postmenopausal women: −0.13 (−0.3;−0.0) at visit 1. At visit 2 the results were similar. When comparing the groups, a statistically significant difference was found between men and post-menopausal women (0.12 (0.0;0.2) P value = 0.04). In the fully adjusted model, SHBG at visit 1 was also associated with HOMA-Ir at visit 2, and the estimated slopes were −0.16 (−0.2;−0.1), −0.16 (−0.3;−0.1) and −0.07 (−0.2;0.0) for men, premenopausal and postmenopausal women, respectively.
Main conclusion
Levels of SHBG predicted the development of insulin resistance in both men and women, regardless of menopausal state.
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Endocrine Unit 2, Department of Clinical and Experimental Medicine, Laboratory of Chemistry and Endocrinology, University Hospital of Pisa, Via Paradisa 2, 56124 Pisa, Italy
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We investigated the prevalence of normocalcemic primary hyperparathyroidism (NPHPT) in the adult population living in a village in Southern Italy. All residents in 2010 (n=2045) were invited by calls and 1046 individuals accepted to participate. Medical history, calcium intake, calcium, albumin, creatinine, parathyroid hormone (PTH) and 25OHD were evaluated. NPHPT was defined by normal albumin-adjusted serum calcium, elevated plasma PTH, and exclusion of common causes of secondary hyperparathyroidism (SHPT) (serum 25OHD <30 ng/ml, estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m2 and thiazide diuretics use), overt gastrointestinal and metabolic bone diseases. Complete data were available for 685 of 1046 subjects. Twenty subjects did not meet the inclusion criteria and 341 could not be evaluated because of thawing of plasma samples. Classical PHPT was diagnosed in four women (0.58%). For diagnosing NPHPT the upper normal limit of PTH was established in the sample of the population (n=100) who had 25OHD ≥30 ng/ml and eGFR ≥60 ml/min per 1.73 m2 and was set at the mean+3s.d. Three males (0.44%) met the diagnostic criteria of NPHPT. These subjects were younger and with lower BMI than those with classical PHPT. Our data suggest, in line with previous studies, that NPHPT might be a distinct clinical entity, being either an early phenotype of asymptomatic PHPT or a distinct variant of it. However, we cannot exclude that NPHPT might also represent an early phase of non-classical SHPT, since other variables, in addition to those currently taken into account for the diagnosis of NPHPT, might cumulate in a normocalcemic subject to increase PTH secretion.