A Challenging Case of Tumor-Induced Osteomalacia: Pathophysiological and Clinical Implications.

We investigated the usefulness of fibroblast growth factor 23 (FGF23) intraoperative assay to monitor tumor resection in patients with oncogenic osteomalacia. A 33-year-old man with 5 years' history of lumbar and pelvis pain together with multiple vertebral fractures was admitted to our hospital. He was diagnosed with ankylosing spondylitis 1 year before. Laboratory investigation showed low tubular reabsorption of phosphate (0.41 mmol/L) despite chronic hypophosphatemia (0.39/L). Increased plasma values of FGF23 (673 pg/mL; n.v. < 95 pg/mL) were also observed. A full-body CT scan showed two suspicious areas in the head of the right femur and in the right tibia; however, the Octreoscan™ showed an increased uptake of the tracer only in the femur. We decided to remove first the head femur lesion and perform intraoperative FGF23 assay to confirm tumor resection; if this had been unsuccessful, we would have extended the operation to excise the second bone lesion. FGF23 basal values and 10, 60, and 225 min after excision of the femoral head were 423, 127, 56, and 30 pg/mL, respectively. The brisk fall of FGF23 values suggested that the head femur lesion was responsible for the syndrome. Histological examination revealed a mesenchymal highly vascular tumor. This is the first report showing the possibility of intraoperative FGF23 assay to monitor tumor resection in patients with tumor-induced osteomalacia.

Update on vitamin D: pros and cons.

Controversies on vitamin D currently represent a challenging topic in mineral metabolism research. In particular, current guidelines on vitamin D supplementation did not report consistent recommendation and the issue related to beneficial vs harmful effects of loading vitamin D doses did not lead to any firm universal conclusion. Finally, serum and clinical outcomes of vitamin D supplementation, particularly as far as extra-skeletal effect of the hormone, need to be further investigated.

The effect of parathyroidectomy on chronic constipation in patients affected by primary hyperparathyroidism.

Primary hyperparathyroidism (PHPT) is usually associated with chronic constipation; however, its prevalence is not defined by standardized criteria. The aim of the study was to evaluate both the prevalence of chronic constipation, defined by the standardized Rome diagnostic criteria III (Rome III) in PHPT, and the effect of parathyroidectomy (PTx). Fifty postmenopausal PHPT patients and 50 sex- and age-matched controls were studied. Each patient underwent mineral metabolism biochemical evaluation and completed a questionnaire and a 2-week diary card about bowel habits. PHPT patients were reevaluated after 6 months. According to Rome III, 40 % of PHPT patients had chronic constipation compared with 12 % of controls (p = 0.0002). The only difference between constipated PHPT patients (group A, n = 20) and those without constipation (group B, n = 30) was higher mean PTH values (79.9 ± 18.7 ng/l vs. 65.4 ± 26.0 ng/l; p = 0.03), which predicted the presence of constipation (p = 0.004, OR 1.059, CI 1.011-1.059). Forty percent of PHPT patients had undergone PTx. In group A, constipation was resolved in 80 % of patients after PTx compared to none of the same group who had not undergone PTx (p = 0.0007). In group B, 17.6 % of patients who had not undergone PTx became, after 6 months, constipated. According to Rome III, a higher prevalence of chronic constipation in PHPT patients was observed compared with controls. PTH levels predicted constipation. A significant reduction of chronic constipation was reported following successful surgery.

Underdiagnosis and undertreatment of osteoporotic patients admitted in internal medicine wards in Italy between 2010 and 2016 (the REPOSI Register).

PURPOSE: To evaluate clinical features, treatments, and outcomes of osteoporotic patients admitted to internal medicine and geriatric wards compared with non-osteoporotic patients (REPOSI registry). METHODS: We studied 4714 patients hospitalized between 2010 and 2016. We reported age, sex, educational level, living status, comorbidities and drugs taken, Cumulative Illness Rating Scale (CIRS), Barthel Index, Short-Blessed Test, 4-item Geriatric Depression Scale, serum hemoglobin, creatinine, and clinical outcomes. Osteoporosis was defined based on the diagnoses recorded at admission, according to the following ICD9: 733, 805-813, 820-823. RESULTS: Twelve percent of the patients had a preadmission diagnosis of osteoporosis. Only 20% of these had been prescribed oral bisphosphonates; 34% were taking vitamin D supplements. Osteoporotic patients were significantly older, with lower BMI, higher CIRS, and taking more drugs. They were significantly more depressed, less independent, with a higher severity of cognitive impairment compared with non-osteoporotic patients. At discharge, the number of patients receiving treatment for osteoporosis did not change. Length of stay and inhospital mortality did not differ between groups. Osteoporotic patients were more frequently nonhome discharged compared with those without osteoporosis (14.8 vs. 7.9%, p = 0.0007), mostly discharged to physical therapy or rehabilitation (8.8 vs. 2.5% of patients, p < 0.0001). Among osteoporotic patients deceased 3 months after discharge, the number of those treated with vitamin D, with or without calcium supplements, was significantly lower compared with survivors (12 vs. 32%, p = 0.0168). CONCLUSIONS: The diagnosis of osteoporosis is poorly considered both during hospital stay and at discharge; osteoporotic patients are frailer compared to non-osteoporotic patients.

Update on the safety and efficacy of teriparatide in the treatment of osteoporosis.

Following the completion of the Fracture Prevention Trial, teriparatide was approved by the United States Food and Drug Administration and the European Medicine Agency as the first therapeutic anabolic agent for the treatment of postmenopausal women with severe osteoporosis. It subsequently received additional approval for the treatment of osteoporosis in men, and for the treatment of osteoporosis associated with glucocorticoid therapy in men and women at risk of fracture. In this review, we summarize the most important data concerning PTH 1-34 therapy before 2016 in the treatment of osteoporosis, and report some outstanding results published in the last 2 years. New data on safety will also discussed, together with the state of art of nonclassical utilization. Finally, in view of the recent approval of biosimilars, possible future landscapes are discussed.

Mineral metabolism abnormalities in patients with prostate cancer: a systematic case controlled study.

PURPOSE: Prostate cancer is the most common tumor in men. To the best of our knowledge a systematic assessment of bone and mineral abnormalities has not been performed in prostatic cancer patients consecutively enrolled. METHODS: This study was therefore carried out to investigate changes of skeletal and mineral metabolism in patients with prostate cancer (n = 69). A population of patients with cancer of various origin was also investigated as a control group (n = 53), since a comparison with non-prostate cancer patients has not been previously reported. RESULTS: In the prostatic cancer group, one patient had extremely high values of C-terminal Fibroblast Growth Factor 23, low values of tubular reabsorption of phosphate and very high values of bone alkaline phosphatase, suggesting the diagnosis of oncogenic osteomalacia. We found nine patients with primary hyperparathyroidism in the group of prostate cancer vs. only one in cancer patients group (p < 0.026). We stratified the population on the basis of Gleason score, prostate specific antigen and hormonal therapy. Using a generalized linear model with a logit link to predict the probability of developing primary hyperparathyroidism, only Gleason score, C-terminal fibroblast growth factor 23 and hormonal therapy had a significant effect (p < 0.05). Controlling for other covariates, a rise in fibroblast growth factor 23 increases the odds of developing primary hyperparathyroidism by 2% (p = 0.017), while patients with higher values of Gleason score have a much greater probability of developing primary hyperparathyroidism (log-odds = 3.6, p < 0.01). The probability decreases with higher values of Gleason score while on hormonal therapy; a further decrease was observed in patients on hormonal treatment and lower values of GS. Finally, lower grade of Gleason score without hormonal therapy have a significant protective factor (p < 0.01) decreasing the odds of developing primary hyperparathyroidism by 8%. CONCLUSION: We showed a remarkable prevalence of primary hyperparathyroidism in men with prostate cancer; the multivariate analysis demonstrates that higher aggressiveness of prostate cancer, as determined by Gleason score, is a significant predictor of increased risk of developing primary hyperparathyroidism.

Reduction of arrhythmias in primary hyperparathyroidism, by parathyroidectomy, evaluated with 24-h ECG monitoring.

OBJECTIVE: Hypercalcemia may induce arrhythmias. There are no data on the prevalence of arrhythmias in primary hyperparathyroidism (PHPT) in daily life. Aim of the study was to investigate both the prevalence of arrhythmias in patients with PHPT compared to controls and the impact of parathyroidectomy, evaluated by 24-h electrocardiogram (ECG) monitoring. DESIGN: This is a randomized study. METHODS: Twenty-six postmenopausal women with PHPT and 26 controls were enrolled. PHPT patients were randomized to two groups: 13 underwent parathyroidectomy (Group A) and 13 were followed up conservatively (Group B). After 6 months, patients were studied again. Each patient underwent mineral metabolism biochemical evaluation, bone mineral density measurement, standard ECG and 24-h ECG monitoring. RESULTS: PHPT patients showed higher calcium and parathyroid hormone compared to controls and a higher prevalence of both supraventricular (SVBPs) and ventricular premature beats (VPBs) during 24-h ECG monitoring. Groups A and B showed no differences in mean baseline biochemical values and ECG parameters. Mean value of QTc in PHPT groups was in the normal range at baseline, but significantly shorter than controls. A negative correlation was found between QTc and ionized calcium levels (r = -0.48, P < 0.05). After parathyroidectomy, Group A had a significant reduction in SVPBs and VPBs compared to baseline and restored normal QTc. Group B showed no significant changes after a 6-month period. CONCLUSIONS: The increased prevalence of SVPBs and VPBs is significantly reduced by parathyroidectomy, and it is mainly related to the short QTc caused by hypercalcemia.

An oral high dose of cholecalciferol restores vitamin D status in deficient postmenopausal HIV-1-infected women independently of protease inhibitors therapy: a pilot study.

The best repletion and maintenance dosing regimens with cholecalciferol in vitamin D-deficient HIV-1 patients remain unknown. Protease inhibitors (PIs) have been shown to inhibit vitamin D 1α- and 25α-hydroxylation in hepatocyte and monocyte cultures. We therefore evaluated the effect of a single high dose of cholecalciferol in vitamin D-deficient HIV-1 postmenopausal women undergoing treatment with highly active anti-retroviral therapy (cART), with and without PIs. Forty HIV-1 postmenopausal women treated with cART, with hypovitaminosis D (<20 ng/ml), were enrolled. We measured serum changes of 25-hydroxyvitamin D [25(OH)D]; 1,25-dihydroxyvitamin D [1,25(OH)2D], parathyroid hormone (PTH), serum calcium, and urinary calcium excretion following a loading dose of 600,000 IU of cholecalciferol after 3, 30, 60, 90, and 120 days. Patients were divided into two groups, whether or not they were taking PI. A significant increase in mean 25(OH)D and 1,25(OH)2D levels at day 3 and throughout the entire observation period was found in both groups (p < 0.001). PTH levels concomitantly decreased in both groups (p < 0.001). Mean albumin-adjusted serum calcium increases with respect to baseline were significant only at day 3 and day 30 for both groups (p < 0.01). Considering remaining parameters, there were no significant differences between the groups at any time, by two-way RM ANOVA. An oral dose of 600,000 IU of cholecalciferol in HIV-1 postmenopausal women rapidly increases 25(OH)D and 1,25(OH)2D levels reducing PTH levels, regardless of the presence of PIs in the cART scheme.

High prevalence of abdominal aortic calcification in patients with primary hyperparathyroidism as evaluated by Kauppila score.

OBJECTIVE: The prevalence of abdominal aortic calcification (AAC) in primary hyperparathyroidism (PHPT) is unknown. We assessed both prevalence and severity of AAC in PHPT postmenopausal women. METHODS: In this study 70 PHPT postmenopausal women and 70 age- and sex-matched controls were enrolled. Each participant underwent biochemical evaluation, lateral spine radiograph, bone mineral density (BMD) measurement (lumbar, femoral, radial sites), and kidney ultrasound. Lateral lumbar films were analyzed in the region of L1-L4 vertebrae and the Kauppila score (a semi-quantitative grading system) was used to assess the severity of AAC. RESULTS: There were no differences regarding demographic and cardiovascular risk factors in the two groups. PHPT patients had higher prevalence of kidney stones (30% vs 7%, P=0.0008) and lower radial BMD values (0.558±0.071 vs 0.588±0.082 g/cm(2), P<0.05) compared with controls. PHPT patients showed higher prevalence of AAC (31 vs 18, P=0.03), with more severe calcifications (Kauppila score 7.35±6.1 vs 5.05±3.5, P=0.007). PHPT patients with AAC were older and had been suffering from the disease for a longer period compared with those without ACC. Moreover, PHPT patients with severe AAC had mean higher serum parathyroid hormone levels compared with patients with moderate or mild calcifications. In PHPT patients with AAC, multiple regression analysis, adjusted for age and years since diagnosis, showed that only parathyroid hormone significantly correlated with Kauppila score. CONCLUSION: We found a higher prevalence and severity of AAC in PHPT related to parathyroid hormone effect.

Vitamin d and its relationship with obesity and muscle.

The skin synthesis of vitamin D represents the first step of a metabolic pathway whose features have been extensively studied and clarified in the last decades. In particular, the production of active and inactive forms of the hormone and the actions of the corresponding enzymes have offered new insights into the knowledge of vitamin D metabolism. Additionally, the description of the different organs and tissues expressing the vitamin D receptor and its possible functions, as well as its genetic determinants, have allowed focusing on the interrelationship between vitamin D and many physiological and pathological functions. In this context, many studies reported the association between vitamin D and adipose tissue metabolism, as well as the possible role of the hormone in obesity, weight, and fat mass distribution. Finally, many reports focused on the vitamin D-related effects on skeletal muscle, particularly on the mechanisms by which vitamin D could directly affect muscle mass and strength. This paper is mainly aimed to review vitamin D metabolism and its relationship with obesity and skeletal muscle function.

Quality of life in patients with primary hyperparathyroidism.

The clinical picture of primary hyperparathyroidism (PHPT) has changed over the last three decades and many asymptomatic patients are now diagnosed through the unexpected finding of high serum calcium levels. However, though not yet considered as typical features of the disease and therefore not included in the guidelines for surgery, many data are available on neuropsycological manifestations and their impact on quality of life in asymptomatic patients. PHPT patients indeed show early experience nonspecific symptoms, such as weakness, depression, sleep disturbance, memory loss and anxiety. Although the underlining mechanisms have not been still identified, the prevalence of psychiatric and cognitive deficits has been investigated in many studies, as well as the possible association with quality of life and well-being improvement after surgery. This article aims to review the current knowledge on quality of life in PHPT patients before and after surgery and the possible clinical implications of these findings.

Parathyroidectomy eliminates arrhythmic risk in primary hyperparathyroidism, as evaluated by exercise test.

OBJECTIVE: To investigate whether parathyroidectomy (PTx) reverses risk factors for arrhythmias related to the QT dynamic changes evaluated during bicycle ergometry exercise test (ET). METHODS: Twenty-four postmenopausal women with primary hyperparathyroidism (PHPT) (mean age 60.08.4 years) and 30 sex- and age-matched controls underwent ET, echocardiography, and biochemical evaluation. The following stages were considered during ET: rest, peak exercise, and recovery. The patients were randomized to two groups: 12 underwent PTx (group A) and 12 were followed-up conservatively (group B). After 6 months, the patients were studied again. RESULTS: Groups A and B showed no differences in mean baseline biochemical values, echocardiographic parameters, and QTC interval. PHPT patients showed an increased occurrence of ventricular premature beats (VPBS) during ET compared with controls (37.0 vs 6.6%, P=0.03). Serum calcium level was a predictor of VPBS (P=0.05). Mean value of QTC was in the normal range at baseline (Group A: 401±16.9; group B: 402.25±13.5 ms) but significantly lower than controls (417.8±25.1 ms, P<0.01). A negative correlation was found between QTc and calcium values (P=0.03). Physiological reduction of QTc interval from rest to peak exercise was not observed in PHPT patients before surgery. After PTx, group A had a significant reduction in VPBs compared with baseline (at baseline, 5 of 12 vs none of 12 patients after PTx, P=0.03) and a restored normal QT adaptation during ET. Group B showed no significant changes after a 6-month period. CONCLUSIONS: PTx reduces the occurrence of VPBs and restored the QTc adaptation during ET.