Recomendaciones de vitamina D para la población general / Recommended vitamin D levels in the general population

Objetivo: Proporcionar recomendaciones basadas en la evidencia sobre el manejo del déficit de vitaminaD en población general. Participantes: Miembros del Grupo de Trabajo de Osteoporosis y Metabolismo Mineral de la SEEN. Métodos: Se empleó el sistema Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) para establecer tanto la fuerza de las recomendaciones como el grado de evidencia. Se realizó una búsqueda sistemática en Medline de la evidencia disponible para vitaminaD y el título de cada capítulo. Se revisaron artículos escritos en inglés con fecha de inclusión hasta 17 de marzo del 2016. Tras la formulación de las recomendaciones, estas se discutieron de manera conjunta en el grupo de trabajo. Conclusiones: Este documento resume los datos acerca del déficit de vitaminaD en lo que respecta a su prevalencia, etiología, indicaciones de cribado, niveles adecuados y efectos de la suplementación a nivel óseo y extraóseo (AU)

Objective: To provide recommendations based on evidence on the management of vitaminD deficiency in the general population. Participants: Members of the Bone Metabolism Working Group of the Spanish Society of Endocrinology. Methods: Recommendations were formulated using the GRADE system (Grading of Recommendations, Assessment, Development, and Evaluation) to describe both the strength of recommendations and the quality of evidence. A systematic search was made in MEDLINE (Pubmed) using the term VitaminD and the name of each issue. Papers in English and Spanish with publication date before 17 March 2016 were included. Recommendations were jointly discussed by the Working Group. Conclusions: This document summarizes the data about vitaminD deficiency in terms of prevalence, etiology, screening indications, adequate levels and effects of supplementation on bone and non-skeletal health outcomes (AU)

Equivalent anticancer activities of dietary vitamin D and calcitriol in an animal model of breast cancer: importance of mammary CYP27B1 for treatment and prevention.

Calcitriol [1,25(OH)2D3], the hormonally active form of vitamin D exerts anti-proliferative, pro-apoptotic, anti-inflammatory effects and other anticancer actions in breast cancer (BCa) cell cultures and animal models of BCa. Our research is focused on investigating the potential beneficial effects of dietary vitamin D3 compared to calcitriol and the underlying mechanisms in BCa treatment and chemoprevention. We recently found that dietary vitamin D3 exhibits significant tumor inhibitory effects in xenograft models of BCa that are equivalent to those elicited by the administration of the active hormone calcitriol. At the easily achievable dose tested in our studies, dietary vitamin D3 exhibited substantial tumor inhibitory activity and, unlike calcitriol, did not cause hypercalcemia demonstrating its relative safety. We found elevations in circulating calcitriol as well as increased CYP27B1 expression in the tumor and the intestine in tumor-bearing mice ingesting a vitamin D3-supplemented diet. We hypothesize that the elevation in circulating 25(OH)D induced by dietary vitamin D3 supplements stimulates local synthesis of calcitriol in the mammary tumor microenvironment and the ensuing paracrine/autocrine actions play a major role in the anticancer activity of dietary vitamin D3. Our findings suggest that the endocrine activity of calcitriol derived from tumor and other extra-renal sources such as the intestine, probably also plays a role in mediating the anticancer effects of dietary vitamin D3. Thus it appears that multiple sites of 1α-hydroxylation contribute to the anticancer effects of dietary vitamin D3. Our data strongly suggest that dietary vitamin D will be useful in the chemoprevention and treatment of BCa since it is a safe, economical and easily available nutritional agent that is equivalent to calcitriol in exerting anticancer effects, at least in mouse models. Furthermore, adequate vitamin D nutrition and avoidance of vitamin D deficiency appear to be important in reducing BCa risk. These findings warrant clinical trials in BCa patients and in women at high risk for BCa to evaluate the benefits of dietary vitamin D3 supplementation. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

Uncommon case of ankylosing spondylitis associated with spontaneous occurring hypoparathyroidism.

Hypoparathyroidism and ankylosing spondylitis are two conditions with distinctive features which allow their differentiation. Hypoparathyroidism can be responsible for clinical and radiological changes resembling those seen in patients with ankylosing spondylitis. We report an exceptional case of a patient with an association between ankylosing spondylitis and a severe idiopathic hypoparathyroidism with difficulties in diagnosis. To our knowledge, this is the first case of such an occurrence.

[Hypocalcemic vitamin D-dependent renal rickets]. / Raquitismo renal hipocalcémico dependiente de vitamina D

Two siblings, female 10 years old, and male 15 years old, with the diagnosis of vitamin D-dependent rickets were studied. Another sibling, also with the same diagnosis, died of bronchopnemonia at about 7 months of age. Both patients developed rachitic manifestations since the first year of life, which persisted despite the administration of massive doses of vitamin D intermitently. Severe hypocalcemia, moderate hypophosphatemia and elevated serum alkaline phosphatase were the most characteristic biochemical findings. Both patients showed diminished renal tubular reabsorption of amino acids and phosphates. These alterations were reversible during I.V. calcium gluconate administration. The clinical biochemical and X-ray manifestations disappeared completely after one year of treatment with dihydrotaquisterol. Vitamin D-dependent rickets is an autosomal recessive disease, characterized by a hydroxylation defect of 25 hydroxycholecalciferol at the carbon 1 level, due to abscence of 25 hydroxy-D1-hydroxylase. Thus 1-25 Dihydroxycholecalciferol, the active form of vitamin D3 is not formed, resulting in depression of intestinal calcium absorption and reabsorption from the bones.