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Xiaoli Jin Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Jiankang Shen Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Tao Liu Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Ru Zhou Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Xunbo Huang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Tianxiang Wang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Weize Wu Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Mingliang Wang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Rongli Xie Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Jianming Yuan Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Objective

The aim was to explore the effects of preoperative calcium and activated vitamin D3 supplementation on post-thyroidectomy hypocalcemia and hypo-parathyroid hormone-emia (hypo-PTHemia).

Methods

A total of 209 patients were randomly divided into control group (CG) and experimental group (EG). Oral calcium and activated vitamin D3 supplementation were preoperatively administered to EG, whereas a placebo was administered to CG. Data on serum calcium, phosphorus, and PTH concentrations before operation, on postoperative day 1 (POPD1), at postoperative week 3 (POPW3), and on the length of postoperative hospitalization were collected.

Results

The serum calcium, phosphorus, and PTH concentrations, as well as the incidence of postoperative hypocalcemia and hypo-PTHemia, did not significantly differ between EG and CG. Subgroup analysis revealed that the serum calcium concentrations of the experimental bilateral thyroidectomy subgroup (eBTS) on POPD1 and POPW3 were higher than that of the control bilateral thyroidectomy subgroup (cBTS) (P < 0.05); the reduction of serum calcium in eBTS on POPD1 and POPW3 was less than those in cBTS (P < 0.05). However, significant differences were not observed between the unilateral thyroidectomy subgroups (UTS) (P > 0.05). Moreover, the incidence of postoperative hypocalcemia in cBTS on POPD1 was significantly higher than that in eBTS (65.9% vs 41.7%) (P < 0.05). The length of hospitalization in cBTS (3.55 ± 1.89 days) was significantly longer than that (2.79 ± 1.15 days) in eBTS (P < 0.05).

Conclusion

Short-term preoperative prophylactic oral calcium and activated vitamin D3 supplementation could effectively reduce the incidence of postoperative hypocalcemia and decrease the length of postoperative hospitalization in patients who have undergone bilateral thyroidectomy.

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Christian Trummer Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria

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Stefan Pilz Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria

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Verena Schwetz Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria

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Barbara Obermayer-Pietsch Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria

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Elisabeth Lerchbaum Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria

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Background

Accumulating evidence from animal and human studies suggests that vitamin D is involved in many functions of the reproductive system in both genders.

Aim

The aim of this review was to provide an overview on the effects of vitamin D on polycystic ovary syndrome (PCOS) in women and androgen metabolism in men.

Methods

We performed a systematic literature search in PubMed for relevant English language publications published from January 2012 until September 2017.

Results and discussion

The vitamin D receptor and vitamin D-metabolizing enzymes are found in reproductive tissues of women and men. In women, vitamin D status has been associated with several features of PCOS. In detail, cross-sectional data suggest a regulatory role of vitamin D in PCOS-related aspects such as ovulatory dysfunction, insulin resistance as well as hyperandrogenism. Moreover, results from randomized controlled trials (RCTs) suggest that vitamin D supplementation may be beneficial for metabolic, endocrine and fertility aspects in PCOS. In men, vitamin D status has been associated with androgen levels and hypogonadism. Further, there is some evidence for a favorable effect of vitamin D supplementation on testosterone concentrations, although others failed to show a significant effect on testosterone levels.

Conclusion

In summary, vitamin D deficiency is associated with adverse fertility outcomes including PCOS and hypogonadism, but the evidence is insufficient to establish causality. High-quality RCTs are needed to further evaluate the effects of vitamin D supplementation in PCOS women as well as on androgen levels in men.

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A Chinoy Royal Manchester Children’s Hospital, Manchester, UK

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M Skae Royal Manchester Children’s Hospital, Manchester, UK

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A Babiker King Abdullah Specialized Children’s Hospital, Riyadh, Saudi Arabia

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D Kendall Royal Preston Hospital, Preston, UK

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M Z Mughal Royal Manchester Children’s Hospital, Manchester, UK

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R Padidela Royal Manchester Children’s Hospital, Manchester, UK

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Background

Hypoparathyroidism is characterised by hypocalcaemia, and standard management is with an active vitamin D analogue and adequate oral calcium intake (dietary and/or supplements). Little is described in the literature about the impact of intercurrent illnesses on calcium homeostasis in children with hypoparathyroidism.

Methods

We describe three children with hypoparathyroidism in whom intercurrent illnesses led to hypocalcaemia and escalation of treatment with alfacalcidol (1-hydroxycholecalciferol) and calcium supplements.

Results

Three infants managed with standard treatment for hypoparathyroidism (two with homozygous mutations in GCMB2 gene and one with Sanjad-Sakati syndrome) developed symptomatic hypocalcaemia (two infants developed seizures) following respiratory or gastrointestinal illnesses. Substantial increases in alfacalcidol doses (up to three times their pre-illness doses) and calcium supplementation were required to achieve acceptable serum calcium concentrations. However, following resolution of illness, these children developed an increase in serum calcium and hypercalciuria, necessitating rapid reduction to pre-illness dosages of alfacalcidol and oral calcium supplementation.

Conclusion

Intercurrent illness may precipitate symptomatic hypocalcaemia in children with hypoparathyroidism, necessitating increase in dosages of alfacalcidol and calcium supplements. Close monitoring is required on resolution of the intercurrent illness, with timely reduction of dosages of active analogues of vitamin D and calcium supplements to prevent hypercalcaemia, hypercalciuria and nephrocalcinosis.

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Raja Padidela Royal Manchester Children’s Hospital and Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK

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Moira S Cheung Evelina London Children’s Hospital, London, UK

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Vrinda Saraff Birmingham Women’s and Children’s Hospital, Birmingham, UK

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Poonam Dharmaraj Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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X-linked hypophosphataemia (XLH) is caused by a pathogenic variant in the PHEX gene, which leads to elevated circulating FGF23. High FGF23 causes hypophosphataemia, reduced active vitamin D concentration and clinically manifests as rickets in children and osteomalacia in children and adults. Conventional therapy for XLH includes oral phosphate and active vitamin D analogues but does not specifically treat the underlying pathophysiology of elevated FGF23-induced hypophosphataemia. In addition, adherence to conventional therapy is limited by frequent daily dosing and side effects such as gastrointestinal symptoms, secondary hyperparathyroidism and nephrocalcinosis. Burosumab, a recombinant human IgG1 MAB that binds to and inhibits the activity of FGF23, is administered subcutaneously every 2 weeks. In clinical trials (phase 2 and 3) burosumab was shown to improve phosphate homeostasis that consequently resolves the skeletal/non-skeletal manifestations of XLH. Burosumab was licensed in Europe (February 2018) with the National Institute for Health and Care Excellence, UK approving use within its marketing authorisation in October 2018. In this publication, the British Paediatric and Adolescent Bone Group (BPABG) reviewed current evidence and provide expert recommendations for care pathway and management of XLH with burosumab.

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Iulia Soare University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania

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Anca Sirbu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Endocrinology, Diabetes and Metabolic diseases, Elias Hospital, Bucharest, Romania

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Mihai Mircea Diculescu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Gastroenterology, Fundeni Clinical Institute, Bucharest, Romania

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Bogdan Radu Mateescu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Gastroenterology, Colentina Hospital, Bucharest, Romania

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Cristian Tieranu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Gastroenterology, Elias Hospital, Bucharest, Romania

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Sorina Martin University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Endocrinology, Diabetes and Metabolic diseases, Elias Hospital, Bucharest, Romania

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Carmen Gabriela Barbu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Endocrinology, Diabetes and Metabolic diseases, Elias Hospital, Bucharest, Romania

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Mirela Ionescu University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Gastroenterology, Elias Hospital, Bucharest, Romania

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Simona Fica University of Medicine and Pharmacy ‘Carol Davila’ Bucharest, Bucharest, Romania
Department of Endocrinology, Diabetes and Metabolic diseases, Elias Hospital, Bucharest, Romania

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Background and aim

Low bone mineral density (BMD) is a common complication in patients with inflammatory bowel disease (IBD). However, debates are ongoing with regard to the other involved factors, especially in younger patients. This study aimed to evaluate the parameters that contribute to decreased BMD, focusing on premenopausal women and men aged <50 years.

Methods

This study included 81 patients with IBD and 81 age-, sex- and BMI-matched controls. Blood tests were conducted on IBD patients, and a dual-energy X-ray absorptiometry (DXA) scan was performed on both groups.

Results

Low BMD and fragility fracture were found to be more prevalent in IBD patients than in healthy subjects (49.3% vs 23.4%, P = 0.001 and 9.8% vs 1.2%, P = 0.01, respectively). Patients with low BMD were older, with a longer disease duration, higher faecal calprotectin (FC) levels and lower magnesium and lean mass (appreciated as appendicular skeletal muscle index (ASMI)). Multiple regression analysis revealed that ASMI, age and use of glucocorticoids were the independent parameters for decreased BMD. Although 91.3% of the patients had a 25-hydroxy vitamin D level of <30 ng/mL, it was not a statistically significant factor for decreased BMD.

Conclusion

In our study, the levels of vitamin D did not seem to have an important impact on BMD. Conversely, FC, magnesium and lean mass are important factors, suggesting that good control of disease, adequate magnesium intake and increased lean mass can have a good impact on bone metabolism in patients with IBD.

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Suma Uday Department of Endocrinology and Diabetes, Birmingham Children’s Hospital, Birmingham, UK

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Ardita Kongjonaj MEAL Specialist at Save the Children International, Albania Country Office, Tirana, Albania

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Magda Aguiar Health Economics Unit, University of Birmingham, Birmingham, UK

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Ted Tulchinsky Braun School of Public Health and Community Medicine, and Ashkelon College, Ashkelon, Israel

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Wolfgang Högler Department of Endocrinology and Diabetes, Birmingham Children’s Hospital, Birmingham, UK
Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK

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Background

Nutritional rickets is a growing global public health concern despite existing prevention programmes and health policies. We aimed to compare infant and childhood vitamin D supplementation policies, implementation strategies and practices across Europe and explore factors influencing adherence.

Methods

European Society for Paediatric Endocrinology Bone and Growth Plate Working Group members and other specialists completed a questionnaire on country-specific vitamin D supplementation policy and child health care programmes, socioeconomic factors, policy implementation strategies and adherence. Factors influencing adherence were assessed using Kendall’s tau-b correlation coefficient.

Results

Responses were received from 29 of 30 European countries (97%). Ninety-six per cent had national policies for infant vitamin D supplementation. Supplements are commenced on day 1–5 in 48% (14/29) of countries, day 6–21 in 48% (14/29); only the UK (1/29) starts supplements at 6 months. Duration of supplementation varied widely (6 months to lifelong in at-risk populations). Good (≥80% of infants), moderate (50–79%) and low adherence (<50%) to supplements was reported by 59% (17/29), 31% (9/29) and 10% (3/29) of countries, respectively. UK reported lowest adherence (5–20%). Factors significantly associated with good adherence were universal supplementation independent of feeding mode (P = 0.007), providing information at neonatal unit (NNU) discharge (P = 0.02), financial family support (P = 0.005); monitoring adherence at surveillance visits (P = 0.001) and the total number of factors adopted (P < 0.001).

Conclusions

Good adherence to supplementation is a multi-task operation that works best when parents are informed at birth, all babies are supplemented, and adherence monitoring is incorporated into child health surveillance visits. Implementation strategies matter for delivering efficient prevention policies.

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Julia Kubiak Tromsø Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway

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Per Medbøe Thorsby Department of Medical Biochemistry, Per Medbøe Thorsby, Hormone Laboratory, Oslo University Hospital, Aker, Norway

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Elena Kamycheva Tromsø Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway
Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway

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Rolf Jorde Tromsø Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway
Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway

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Objective

Low serum 25(OH)D levels are associated with cardiovascular disease (CVD) and some of its risk factors. However, in interventional studies, the effects of vitamin D supplementation have been uncertain, possibly due to inclusion of vitamin D-sufficient subjects. Our aim was therefore to examine effects of vitamin D supplementation on CVD risk factors in vitamin D-insufficient subjects.

Design

Double-blinded randomized controlled trial.

Methods

A 4-month interventional study with high-dose vitamin D (100,000 IU loading dose, followed by 20,000 IU/week) or placebo with measurements of blood pressure, lipids (total-, LDL- and HDL-cholesterol, triglycerides, apolipoproteins A1 and B), and glucose metabolism parameters (blood glucose, HbA1c, serum human receptors for advanced glycation end products (sRAGE), insulin, C-peptide and HOMA-IR).

Results

A total of 422 subjects with mean serum 25(OH)D level 34 nmol/L were included, with 411 subjects completing the study. Serum 25(OH)D levels increased with 56 nmol/L and decreased with 4 nmol/L in the vitamin D and placebo group, respectively. We found no statistically significant differences between the two groups in any of the measured CVD risk factors, except for a minor increase in sRAGE in the vitamin D group. Stratified analyses of subjects with low baseline serum 25(OH)D levels alone, or combined with blood pressure, lipid and HOMA-IR values above the median for the cohort, did not skew the results in favour of vitamin D supplementation.

Conclusion

Supplementation with vitamin D in subjects with baseline vitamin D insufficiency does not improve CVD risk factor profile.

Open access
Elena Valassi Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Natalia García-Giralt URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), Universitat Autònoma de Barcelona, Barcelona, Spain

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Jorge Malouf Mineral Metabolism Unit, Medicine Department, Hospital Sant Pau, Barcelona, Spain

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Iris Crespo Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Jaume Llauger Radiology Department, Hospital Sant Pau, Barcelona, Spain

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Adolfo Díez-Pérez URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), Universitat Autònoma de Barcelona, Barcelona, Spain

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Susan M Webb Endocrinology/Medicine Department, Hospital Sant Pau, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER, Unidad 747), IIB-Sant Pau, ISCIII and Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

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Background

Biochemical control of GH/IGF-I excess in acromegaly (ACRO) is associated with persistent impairment of trabecular microstructure leading to increased risk of vertebral fractures. Circulating miRNAs modulate the activity of osteoblasts and osteoclasts, and may be potential biomarkers of osteoporosis.

Aims

Identify differentially expressed miRNAs in the serum of patients with controlled ACRO vs controls and correlate miRNA levels with both biochemical and structural bone parameters.

Patients and methods

Twenty-seven patients with controlled ACRO (11 males, 16 females; mean age, 48 ± 5 years; BMI, 28 ± 4 kg/m2) and 27 age-, gender- and BMI-matched controls were recruited. Areal BMD at lumbar spine and femur, and trabecular bone score were assessed; volumetric BMD was measured by quantitative computed tomography QCT-Pro (Mindways). Twenty miRNAs, chosen by their putative role in bone, were quantified in serum using real-time qPCR.

Results

In ACRO patients, miR-103a-3p and miR-191-5p were found overexpressed, whereas miR-660-5p was underexpressed (P < 0.001). miR-103a-3p levels were negatively associated with both trabecular vBMD at trochanter and serum osteoprotegerin concentrations (P < 0.05) and positively with vitamin D concentrations (P < 0.01) and total cross-sectional area of the femoral neck (P < 0.05). miR-660-5p levels were correlated with both trabecular vBMD at trochanter and OPG concentrations (P < 0.05), but were negatively associated with vitamin D levels (P < 0.05). A negative correlation between miR-103-a-3p and miR-660-5p was found in both groups (P < 0.001).

Conclusions

Circulating miR-103a-3p and miR-660-5p are differentially expressed in controlled ACRO patients and associated with bone structural parameters. miRNAs may be one of the mechanisms involved in the pathogenesis of bone disease and could be used as biomarkers in ACRO patients.

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Rolf Jorde Tromsø Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway
Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway

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Guri Grimnes Tromsø Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway
Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway

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Objective

In addition to its skeletal effects, vitamin D may also be important for health in general. It is uncertain what level of serum 25-hydroxyvitamin D (25(OH)D), marker of vitamin D status, is sufficient for these effects. With decreasing serum 25(OH)D levels there is an increase in serum PTH. The point at which this occurs has been considered as a threshold for vitamin D sufficiency. The thresholds found have varied widely and have mainly been based on observational studies. However, to truly establish a threshold for vitamin D effects, this has to be based on randomized controlled trials (RCTs).

Methods

The study included 2803 subjects from a general health survey, the Tromsø study, and pooled individual person data from five vitamin D intervention studies (n = 1544). Serum parathyroid hormone (PTH) and change in PTH after vitamin D supplementation were related to serum 25(OH)D levels in steps of 25 nmol/L (<24, 25–49, 50–74, 75–99, and >99 nmol/L).

Results

In the Tromsø study, in the females there was a gradual decrease in serum PTH with increasing serum 25(OH)D with no apparent plateau, whereas in the males the decrease in PTH in subjects with serum 25(OH)D >74 nmol/l was marginal. In pooled RCTs, there was a significant reduction in serum PTH by vitamin D supplementation regardless of baseline serum 25(OH)D level.

Conclusions

The use of the serum PTH–25(OH)D relation from observational studies to determine a threshold for vitamin D sufficiency is highly questionable.

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Giuseppe Grande Unit of Andrology and Reproductive Medicine, University Hospital of Padova, Padova, Italy

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Andrea Graziani Department of Medicine, University of Padova, Padova, Italy

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Antonella Di Mambro Unit of Andrology and Reproductive Medicine, University Hospital of Padova, Padova, Italy

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Riccardo Selice Unit of Andrology and Reproductive Medicine, University Hospital of Padova, Padova, Italy

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Alberto Ferlin Unit of Andrology and Reproductive Medicine, University Hospital of Padova, Padova, Italy
Department of Medicine, University of Padova, Padova, Italy

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Low bone mass is common in men with Klinefelter syndrome (KS), with a prevalence of 6–15% of osteoporosis and of 25–48% of osteopenia. Reduced bone mass has been described since adolescence and it might be related to both reduced bone formation and higher bone resorption. Although reduced testosterone levels are clearly involved in the pathogenesis, this relation is not always evident. Importantly, fracture risk is increased independently from bone mineral density (BMD) and testosterone levels. Here we discuss the pathogenesis of osteoporosis in patients with KS, with a particular focus on the role of testosterone and testis function. In fact, other hormonal mechanisms, such as global Leydig cell dysfunction, causing reduced insulin-like factor 3 and 25-OH vitamin D levels, and high follicle-stimulating hormone and estradiol levels, might be involved. Furthermore, genetic aspects related to the supernumerary X chromosome might be involved, as well as androgen receptor expression and function. Notably, body composition, skeletal mass and strength, and age at diagnosis are other important aspects. Although dual-energy x-ray absorptiometry is recommended in the clinical workflow for patients with KS to measure BMD, recent evidence suggests that alterations in the microarchitecture of the bones and vertebral fractures might be present even in subjects with normal BMD. Therefore, analysis of trabecular bone score, high-resolution peripheral quantitative computed tomography and vertebral morphometry seem promising tools to better estimate the fracture risk of patients with KS. This review also summarizes the evidence on the best available treatments for osteoporosis in men with KS, with or without hypogonadism.

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