Vitamin D is essential for the maintenance of good health. Its sources can be skin production and diet intake. Most humans depend on sunlight exposure (UVB 290315 nm) to satisfy their requirements for vitamin D. Solar ultraviolet B photons are absorbed by the skin, leading to transformation of 7-dehydrocholesterol into vitamin D3 (cholecalciferol). Season, latitude, time of day, skin pigmentation, aging, sunscreen use, all influence the cutaneous production of vitamin D3. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risk for other morbidities such as cardiovascular disease, type 1 and type 2 diabetes mellitus and cancer, especially of the colon and prostate. The prevalence of hypovitaminosis D is considerable even in low latitudes and should be taken into account in the evaluation of postmenopausal and male osteoporosis. Although severe vitamin D deficiency leading to rickets or osteomalacia is rare in Brazil, there is accumulating evidence of the frequent occurrence of subclinical vitamin D deficiency, especially in elderly people.

Bone disease in severe primary hyperparathyroidism (PHPT) is described classically as osteitis fibrosa cystica (OFC). Bone pain, skeletal deformities and pathological fractures are features of OFC. Bone mineral density is usually extremely low in OFC, but it is reversible after surgical cure. The signs and symptoms of severe bone disease include bone pain, pathologic fractures, proximal muscle weakness with hyperreflexia. Bone involvement is typically characterized as salt-and-pepper appearance in the skull, bone erosions and bone resorption of the phalanges, brown tumors and cysts. In the radiography, diffuse demineralization is observed, along with pathological fractures, particularly in the long bones of the extremities. In severe, symptomatic PHPT, marked elevation of the serum calcium and PTH concentrations are seen and renal involvement is manifested by nephrolithiasis and nephrocalcinosis. A new technology, recently approved for clinical use in the United States and Europe, is likely to become more widely available because it is an adaptation of the lumbar spine DXA image. Trabecular bone score (TBS) is a gray-level textural analysis that provides an indirect index of trabecular microarchitecture. Newer technologies, such as high-resolution peripheral quantitative computed tomography (HR-pQCT), have provided further understanding of the microstructural skeletal features in PHPT.

Since the last international guidelines were published in 2014 on the evaluation and management of primary hyperparathyroidism (PHPT), new information has become available with regard to evaluation, diagnosis, epidemiology, genetics, classical and nonclassical manifestations, surgical and nonsurgical approaches, and natural history. To provide the most current summary of these developments, an international group, consisting of over 50 experts in these various aspects of PHPT, was convened. This paper provides the results of the task force that was assigned to review the information on the management of PHPT. For this task force on the management of PHPT, two questions were the subject of systematic reviews using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology. The full report addressing surgical and nonsurgical management of PHPT, utilizing the GRADE methodology, is published separately in this series. In this report, we summarize the results of that methodological review and expand them to encompass a much larger body of new knowledge that did not specifically fit the criteria of the GRADE methodology. Together, both the systematic and narrative reviews of the literature, summarized in this paper, give the most complete information available to date. A panel of experts then considered the last set of international guidelines in light of the newer data and assessed the need for their revision. This report provides the evidentiary background to the guidelines report. In that report, evidence from all task forces is synthesized into a summary statement and revised guidelines for the evaluation and management of PHPT. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

OBJECTIVE: To describe the characteristics of normocalcemic primary hyperparathyroidism (NPHPT) in patients seen for osteoporosis evaluation. PATIENTS AND METHODS: We examined the records of 156 women who came to the hospital to be screened for osteoporosis. Measurements of total calcium, PTH, 25-hydroxy vitamin D, and β-C-telopeptide were recorded. Bone mineral density and T-scores were evaluated by densitometry of the lumbar spine, femoral neck and distal one-third of the radius. The latter was only measured in patients with primary hyperparathyroidism. Nephrolithiasis and bone fractures were documented by a review of the medical records. RESULTS: We identified 14 patients with NPHPT, accounting for 8.9% of the population studied. In the medical records, the occurrence of kidney stones was reported in 28.6% of the patients with NPHPT, in contrast with only 0.7% of the noncarriers. Regarding the presence of general fractures, 21.4% of the patients with NPHPT were affected versus 16.2% of noncarriers. CONCLUSION: Data from our study suggest that NPHPT has a diverse phenotypic presentation, implying that this may not be an "indolent" disease.

OBJECTIVE: To determine vitamin D (25OHD) status and its relationship with bone mineral density (BMD) in 93 postmenopausal women. SUBJECTS AND METHODS: Patients were distributed in two groups: Group 1 - 51 to 65 years (n = 45) and Group 2 - 66 to 84 years (n = 48); 25OHD and PTH serum were analyzed and a DXA scan of the lumbar spine (LS) and femoral neck (FN) were taken. RESULTS: Mean ± SD of serum 25OHD levels were 80.6 ± 43.3 nmol/L (Group 1) and 63.7 ± 27.6 nmol/L (Group 2); 24% had 25OHD levels < 25 nmol/L and 43.7% < 50 nmol/L. The prevalence of vitamin D deficiency at the 62.5 nmol/L cutoff increased significantly with age. Patients with hypovitaminosis D had a lower BMD at the FN (0.738 ± 0.102 vs. 0.793 ± 0.115 g/cm, p = 0.03) and had been postmenopausal for longer (21.0 ± 8.4 vs. 16.2 ± 8.4 years, p = 0.01). CONCLUSION: We found a high prevalence of hypovitaminosis D in postmenopausal women. Age, years elapsed since menopause and low BMD in the FN were associated with deficiency.

Hypovitaminosis D is a common condition with a negative impact on health. This statement, prepared by experts from the Brazilian Society of Endocrinology and Metabolism and the Brazilian Society of Clinical Pathology/Laboratory Medicine, includes methodological aspects and limitations of the measurement of 25-hydroxyvitamin D [25(OH)D] for identification of vitamin D status, and identifies individuals at increased risk for deficiency of this vitamin in whom 25(OH)D measurement is recommended. For the general population, 25(OH)D levels between 20 and 60 ng/mL are considered normal, while individuals with levels below 20 ng/mL are considered to be vitamin D deficient. This statement identifies potential benefits of maintaining 25(OH)D levels > 30 ng/mL in specific conditions, including patients aged > 65 years or pregnant, those with recurrent falls, fragility fractures, osteoporosis, secondary hyperparathyroidism, chronic kidney disease, or cancer, and individuals using drugs with the potential to affect the vitamin D metabolism. This statement also calls attention to the risk of vitamin D intoxication, a life-threatening condition that occurs at 25(OH)D levels above 100 ng/mL