Vitamin D concentrations and their relationship with iron parameters in patients with chronic kidney disease / Concentrações de vitamina D e sua relação com parâmetros de ferro em pacientes com doença renal crônica

ABSTRACT Objective To investigate the relationship between calcidiol (25(OH)D3) concentrations and iron parameters in patients with chronic kidney disease. Methods This is a cross-sectional, descriptive, and quantitative study. The sample consisted of 86 adult patients of both sexes undergoing dialysis. 25(OH)D3 concentrations were determined by chemiluminescence; food consumption was assessed using 24-hour recalls, and the serum levels of hemoglobin, iron, ferritin, and transferrin saturation were assessed. Data analysis was performed using the program Stata, with a significance level of p<0.05. Results The results pointed to 25(OH)D3 concentrations compatible with sufficiency, iron levels consistent with normality, and ferritin and transferrin saturation above the reference values. The consumption of carbohydrates and lipids was higher in females. There was no relationship between the adequacy of 25(OH)D3 and the presence of anemia and iron parameters. Conclusion Considering that the mean serum levels of iron and 25(OH)D3 were adequate, it is suggested that resistance to erythropoietin and the inflammatory process may have contributed to the percentage of anemic individuals found in the study.

RESUMO Objetivo Investigar a relação entre as concentrações de calcidiol (25(OH)D3) e os parâmetros de ferro em pacientes com doença renal crônica. Métodos É um estudo transversal, descritivo e quantitativo. A amostra foi composta por 86 pacientes, adultos, de ambos os sexos, em terapia dialítica. As concentrações de 25(OH)D3 foram determinadas pelo método de quimioluminescência; o consumo alimentar foi avaliado pela aplicação de Recordatórios de 24 horas e foram avaliados os níveis séricos de hemoglobina, ferro, ferritina e saturação de transferrina. A análise dos dados foi realizada no programa Stata, com nível de significância p<0.05. Resultados Os resultados apontaram para concentrações de 25(OH)D3 compatíveis com suficiência, níveis de ferro compatíveis com a normalidade e ferritina e saturação de transferrina superiores à referência. O consumo de carboidratos e lipídios foi superior no sexo feminino. Não foi verificada relação entre a adequação de 25(OH)D3 e a presença de anemia e parâmetros de ferro. Conclusão Tendo em vista que os níveis médios séricos de ferro e 25(OH)D3 estavam adequados, sugere-se que a resistência à eritropoietina e o processo inflamatório podem ter contribuído para o percentual de anêmicos constatado no estudo.

Variación estacional de 25-hidroxi-vitamina D3, hormona paratiroidea y fosfatasa alcalina en niños escolares / Seasonal variations in 25-hydroxy vitamin D3, parathormone and alkaline phosphatase in school-aged children

INTRODUCCIÓN: El principal rol de la vitamina D es la regulación del metabolismo del calcio, cuya principal fuen te es la vitamina D3 que se obtiene principalmente por la acción de la luz ultravioleta (UV) en la piel. OBJETIVO: Evaluar las diferencias estacionales en las concentraciones de 25-hidroxi-vitamina D3 (25OHVitD3), hormona paratiroidea (PTH), fosfatasa alcalina (FA) y calcio en niños en edad esco lar. SUJETOS Y MÉTODO: Se midieron las concentraciones de 25OHVitD3, PTH, FA y calcio en niños de 5 a 8 años, sin suplementación de Vitamina D, reclutados en Santiago de Chile (latitud -33.4372) en distintas estaciones del año. El estatus de VitD fue definido como suficiente con concentraciones de 25OHVitD3 > 20 ng/mL (50 nmol/L), insuficiente 12-20 ng/mL (30-50 nmol/L) y deficiente 20 ng/mL) en verano, lo que disminuyó significativamente en invierno (54,3%, p < 0,0001). CONCLUSIONES: Las concentraciones de 25OHVitD3 disminuyeron en aproximadamente la mitad de los niños durante el invierno, lo que se vio acompañado de un aumento de la PTH y FA, asociado a concentraciones normales de calcio. De acuerdo a nuestros resultados, la suplementación con VitD en niños podría ser necesaria durante otoño e invierno.

INTRODUCTION: The main role of Vitamin D is to regulate calcium metabolism, whose main source is vitamin D3 ob tained mostly from the action of ultraviolet (UV) light on the skin. OBJECTIVE: To evaluate the seaso nal differences in the concentrations of 25-hydroxy-vitamin D3 (25OHVitD3), parathyroid hormone (PTH), alkaline phosphatase (ALP), and calcium in school-age children. SUBJECTS AND METHOD: The concentrations of 25OHVitD3, PTH, ALP, and calcium were measured in children from Santiago, Chile (latitude -33.4372), aged 5 to 8 years, without Vitamin D supplementation, in different seasons of the year. VitD status was defined as sufficient with concentrations of 25OHVitD3 >20 ng/mL (50 nmol/L), insufficient 12-20 ng/mL (30-50 nmol/L) and deficient 20 ng/mL), which decreased significantly in winter to 54.3% (p <0.0001). CONCLUSIONS: In winter, 25OHVitD3 concentrations decreased in approximately half of the children, which was associated with an increase in PTH and ALP, and normal calcium concentrations. According to our results, children may need VitD supple mentation during fall and winter.

25 (OH) D3 levels, incidence and recurrence of different clinical forms of benig paroxysmal positional vertigo / Níveis de 25 (OH) D3, incidência e recorrência de diferentes formas clínicas de vertigem posicional paroxística benigna

Abstract Introduction Benign paroxysmal positional vertigo is the most common cause of dizziness in the general population. It is a condition with potential impact of reduced levels of vitamin D on its recurrent attacks. Objectives The aim of this study was to measure the serum levels of 25-hydroxyvitamin D3 (25-OH D3) in patients with benign paroxysmal positional vertigo and determine whether there is a difference in the serum levels of vitamin D3 between patients with and without recurrence, as well as between the different clinical forms of benign paroxysmal positional vertigo. Methods The study included 40 patients who came to the regular medical examination, diagnosed with posterior canal-benign paroxysmal positional vertigo based on the positive Dix-Hallpike's test. All patients underwent Epley manoeuvre after the diagnosis. Patients were classified according to current guidelines for levels of vitamin D3 in the serum in three groups: the deficiency, insufficiency and adequate level. Results The average serum level of 25-OH D3 among respondents was 20.78 ng/mL, indicating a lack or insufficiency of the aforementioned 25-OH D3. According to the levels of 25-OH D3, most patients suffer from deficiency (47.5%). 7 (17.5%) respondents had adequate blood level of 25-OH D3, and 14 (35%) respondents suffer from insufficiency. A significant difference was not found in the serum level of 25-OH D3 between patients with and without benign paroxysmal positional vertigo recurrence. There was a significant difference in the serum levels of 25-OH D3 in comparison to the clinical form of the disease. Lower 25-OH D3 values were found in patients with canalithiasis compared to those with cupulolithiasis. Conclusions There were no significant differences in the vitamin D3 serum level in patients with and without recurrence. The study showed a low level of serum vitamin D3 in most patients, indicating the need for supplemental therapy.

Resumo Introdução Vertigem posicional paroxística benigna é a causa mais comum de tonturas na população em geral. É uma condição no qual níveis reduzidos de vitamina D podem ter um potencial impacto para o desenvolvimento de crises recorrentes. Objetivos O objetivo desse estudo foi medir os níveis séricos de 25-hidroxivitamina D3 (25-OH D3) em pacientes com vertigem posicional paroxística benigna e determinar se há diferença nos níveis séricos de vitamina D3 entre pacientes com e sem recorrência, bem como entre as diferentes formas clínicas de vertigem posicional paroxística benigna. Método O estudo incluiu 40 pacientes submetidos a exame médico regular, diagnosticados com vertigem posicional paroxística benigna de canal posterior baseado no resultado positivo do teste de Dix-Hallpike. Todos os pacientes foram submetidos à manobra de Epley após o diagnóstico. Os pacientes foram classificados de acordo com as diretrizes atuais para os níveis de vitamina D3 sérica em três grupos: deficiência, insuficiência e nível adequado. Resultados O nível sérico médio de 25-OH D3 entre os indivíduos avaliados foi de 20,78 ng/mL, indicando falta ou insuficiência desta vitamina. De acordo com os níveis de 25-OH D3, a maioria dos pacientes apresentou deficiência (47,5%). Sete indivíduos (17,5%) entrevistados tinham nível sanguíneo adequado de 25-OH D3 e 14 (35%) apresentavam insuficiência. Não foi encontrada diferença significativa no nível sérico de 25-OH D3 entre pacientes com e sem recidiva de vertigem posicional paroxística benigna. Houve uma diferença significativa nos níveis séricos de 25-OH D3 de acordo com a forma clínica da doença. Baixos níveis de 25-OH D3 foram mais encontrados em pacientes com canalitíase em comparação com aqueles com cupulolitíase. Conclusões Não houve diferenças significativas no nível sérico de vitamina D3 em pacientes com e sem recorrência. O estudo mostrou um baixo nível de vitamina D3 sérica na maioria dos pacientes, indicando a necessidade de terapia suplementar.

Vitamin D in prostate cancer / 亚洲男科学杂志(英文版)

Signaling through the vitamin D receptor has been shown to be biologically active and important in a number of preclinical studies in prostate and other cancers. Epidemiologic data also indicate that vitamin D signaling may be important in the cause and prognosis of prostate and other cancers. These data indicate that perturbation of vitamin D signaling may be a target for the prevention and treatment of prostate cancer. Large studies of vitamin D supplementation will be required to determine whether these observations can be translated into prevention strategies. This paper reviews the available data in the use of vitamin D compounds in the treatment of prostate cancer. Clinical data are limited which support the use of vitamin D compounds in the management of men with prostate cancer. However, clinical trials guided by existing preclinical data are limited.

Hypocalcemia development in patients operated for primary hyperparathyroidism: Can it be predicted preoperatively?

ABSTRACT Objective Primary hyperparathyroidism (PHP) is a common endocrine disease, and its most effective treatment is surgery. Postoperative hypocalcemia is a morbidity of parathyroid surgeries, and it may extend hospitalization durations. The purpose of this study is to determine the predictive factors related to the development of hypocalcemia and hungry bone syndrome (HBS) in patients who underwent parathyroidectomy for PHP. Materials and methods Laboratory data comprising parathyroid hormone (PTH), calcium, phosphate, 25-OHD, albumin, magnesium, alkaline phosphatase (ALP), blood urea nitrogen (BUN), and thyroid stimulating hormone (TSH) of the patients were recorded preoperatively, on the 1st and 4th days postoperatively, and in the 6th postoperative month, and their neck ultrasound (US) and bone densitometry data were also recorded. Results Hypocalcemia was seen in 63 patients (38.4%) on the 1st day after parathyroidectomy. Ten patients (6.1%) had permanent hypocalcemia in the 6th month after surgery. Out of the patients who underwent parathyroidectomy for PHP, 22 (13.4%) had HBS. The incidence of postoperative hypocalcemia was higher in patients who underwent parathyroidectomy for PHP, who had parathyroid hyperplasia, and who had osteoporosis. Preoperative PTH, ALP, and BUN values were higher in those patients who developed HBS. Furthermore, HBS was more common in patients who had osteoporosis, who had parathyroid hyperplasia, and who underwent thyroidectomy simultaneously with parathyroidectomy. Conclusions As a result, patients who have the risk factors for development of hypocalcemia and HBS should be monitored more attentively during the perioperative period.

Vitamin D deficiency and hypertension in type 2 diabetic Iraqi patients

Objective: Vitamin D[3] deficiency has been defined as serum 25-hydroxyvitamin D[3][25-[OH]D[3]] levels below 30 ng/ml and it is common among patients with type 2 diabetes mellitus [T2DM]. Laboratory studies indicate that 1,25-[OH]D[3] suppresses renin expression and vascular smooth muscle cells proliferation, then decreases blood pressure. The aim of the present study is to demonstrate the association between 25-[OH]D[3] level and the risk of blood pressure, and its relation with T2DM and body mass index [BMI]

Method: This study was conducted at Al-Hussein Medical City/Al-Hussein Teaching Hospital, Karbala, Iraq. All samples, 30 apparently healthy subjects as control, N = 30 and 90 patients [equal number of male and female] with T2DM [50 obese with hypertension [G1] and 40 non-obese without hypertension [G2]], were randomly selected from diabetic patients who had attended the diabetic consultation unit from November 2012 to June 2013 with age ranged between 23 and 75 years. Measurement of 25-[OH]D[3], fasting blood glucose, triglyceride, total cholesterol and high-density lipoprotein cholesterol [HDL-C] levels in addition to blood pressure and BMI were calculated in all samples

Results: The results showed that serum 25-[OH]D[3] was significantly decreased in G1 and G2 groups [16.8 +/- 8.8 ng/ml, 19.5 +/- 9.7 ng/ml, respectively], compared with control group [36.0 +/- 9.4 ng/ml] at P < 0.001, and 68% of female vs. 57% of male underwent this deficiency. Also 25-[OH]D[3] had negative correlation with blood pressure, fasting blood sugar, triglycerides and BMI in diabetic patients in G1 at P < 0.0001 and it had positive significant correlation with HDL-C in G1 and G2 groups

Conclusion: It can be concluded that T2DM, systolic and diastolic blood pressure levels correlates significantly with lower concentration of 25-[OH]D[3], which suggested that clinical experiences should be taking into account the protective effect of vitamin D in decrease hypertension, which reflects risk factors in diabetic patients with hypertension that leads to metabolic syndrome and then to cardiovascular diseases

Recomendações da Sociedade Brasileira de Endocrinologia e Metabologia (SBEM) para o diagnóstico e tratamento da hipovitaminose D / Recommendations of the Brazilian Society of Endocrinology and Metabology (SBEM) for the diagnosis and treatment of hypovitaminosis D

Objetivo Apresentar uma atualização sobre o diagnóstico e tratamento da hipovitaminose D baseada nas mais recentes evidências científicas. Materiais e métodos O Departamento de Metabolismo Ósseo e Mineral da Sociedade Brasileira de Endocrinologia e Metabologia (SBEM) foi convidado a conceber um documento seguindo as normas do Programa Diretrizes da Associação Médica Brasileira (AMB). A busca dos dados foi realizada por meio do PubMed, Lilacs e SciELO e foi feita uma classificação das evidências em níveis de recomendação, de acordo com a força científica por tipo de estudo. Conclusão Foi apresentada uma atualização científica a respeito da hipovitaminose D que servirá de base para o diagnóstico e tratamento dessa condição no Brasil. .

Objective The objective is to present an update on the diagnosis and treatment of hypovitaminosis D, based on the most recent scientific evidence. Materials and methods The Department of Bone and Mineral Metabolism of the Brazilian Society of Endocrinology and Metabology (SBEM) was invited to generate a document following the rules of the Brazilian Medical Association (AMB) Guidelines Program. Data search was performed using PubMed, Lilacs and SciELO and the evidence was classified in recommendation levels, according to the scientific strength and study type. Conclusion A scientific update regarding hypovitaminosis D was presented to serve as the basis for the diagnosis and treatment of this condition in Brazil. .

Does serum 25 hydroxy vitamin D level play a role in COPD?

It has been recogni/ed that, in addition to Us classical function, vitamin D modulates a variety of processes and regulators systems including host defense, inflammation, and immunity. Some authors concluded that there is strong relation between vitamin I] serum level and lung functions but others concluded that there is no relation between them. To stuck the role of serum level of 25 hydroxy-vitamin D in COPD patients, also, assess the serum level of vitaniin D dependent LL-37 and IFNgamma and to study the link between the three parameters and pulmonary functions in these patients. This study was conducted on 40 persons who were divided into Gl. 10 controls and GIl. 30 COPD patients. FF.V1. serum levels of 25 hydroxv vitamin D. LL-37 and IFNgamma were measured. Serum levels of 25 hydroxy vitamin D and LL-37 were significantly decreased in GIl as compared to GI while serum llevel of IFNgamma was significantly increased in Gil as compared to GI and there was a significant positive correlation between vitamin D level and FEV1 and LL-37 level while there was a negative correlation between it and IFNgamma level. Vitamin I] level affects pulmonary function in COPD through its effect on LL-37 and IFNgamma serum level

determination of 25-OH vitamin [D2/D3] in human serum by liquid chromatography tandem mass spectrometry with comparison to IDS enzyme immunoassay

The proper assessment of the status of vitamin D requires the accurate measurement of both 25-OH vitamin D2 and 25- OH vitamin D3, which collectively constitute 25-OH vitamin D, the best indicator of vitamin D status. Currently, numerous assay methods are available for 25-OH vitamin D measurement but their comparability is uncertain. We employed isotope dilution liquid chromatography coupled with tandem mass spectrometry [ID-LC-MS/MS] to quantify 25-OH vitamin D2 and 25-OH vitamin D3 in human serum. Hexadeuterium labeled 25-OH vitamin D3 internal standard was added to calibrators, controls prepared in 6% bovine serum albumin in phosphate buffered saline, and patients' sera. Zinc sulphate was added to release 25-OH vitamin D metabolites for vitamin D binding protein, followed by a precipitation step with the addition of acetonitrile. Subsequent online phase extraction by trap column followed by chromatographic separation on a C-8 column using a water/acetonitrile gradient was employed. Detection was performed using Atmospheric Pressure Chemical Ionization [AP-CI] in a Multiple Reaction Monitoring [MRM] mode. The method was linear from 4 to 70 ng/mL. The intra and inter-day CV% were

Prevalence and risk factors for vitamin D deficiency among mothers in labor and their newborns

Vitamin D deficiency is recognized as a global public health problem. Studies of vitamin D levels in mothers in labor and their newborns in Bahrain are lacking. The aim of this study is to identify the prevalence of vitamin D [25[OH]D] deficiency among mothers in labor and their newborns in Bahrain. A cross-sectional multicenter study. Four Public and Four Private Maternity Hospitals in Bahrain. The study was conducted in April 2012. It included mothers in labor and their newborns. Differences between the subgroups were analyzed using Chi-Square or Student's t-test as appropriate. Linear regression analysis was used to evaluate independent predictors of 25[OH]D level. The study included 403 mothers and 403 newborns. Overall prevalence of 25[OH]D deficiency [<50 nmol] was 358 [88.8%] of the mothers and 364 [90.3%] of the newborns. The mean maternal alkaline phosphatase level was significantly higher than the neonatal level and the maternal mean calcium was significantly lower than the neonatal level. Significant association with vitamin D deficiency was found among Bahraini and non-Bahraini Arab mothers, delivering in public rather than private hospital, living in flats, low education, the use of veil, gravida >/= 4, not using multivitamins, vitamin D or calcium supplements. Vitamin D deficiency among mothers and their newborns is high. This mandates increasing awareness, vitamin D supplementation among mothers in labor and their infants; in addition to the introduction of vitamin D fortification of dairy products and flour at the national level

Níveis séricos de 25-hidroxivitamina D3 e sua associação com parâmetros clínicos e laboratoriais em pacientes com lúpus eritematoso sistêmico / 25-Hydroxyivitamin D3 levels in patients with systemic lupus erythematosus and its association with clinical parameters and laboratory tests

INTRODUÇÃO: O papel imunorregulatório da vitamina D tem sido alvo de um crescente número de estudos em pacientes com lúpus eritematoso sistêmico (LES). Objetivos: Determinar os níveis séricos de 25-hidroxivitamina D3 [25(OH)D] em pacientes com LES e verificar a associação da insuficiência/deficiência de 25(OH)D com parâmetros clínicos e laboratoriais. MÉTODOS:Estudo de corte transversal, prospectivo, realizado no ambulatório de LES do Serviço de Reumatologia do Hospital das Clínicas da Universidade Federal de Pernambuco. Foram incluídos 78 pacientes portadores de LES e 64 voluntários (grupo de comparação) pareados por gênero e idade. RESULTADOS: Constatou-se insuficiência/deficiência de 25(OH)D em 45 (57,7 por cento) pacientes com LES e em 25 (39 por cento) indivíduos do grupo de comparação. Os níveis séricos médios de 25(OH)D foram 29,3 ng/mL (6,1-55,2 ng/mL) nos pacientes com LES e 33,12 ng/mL (15,9-63,8 ng/mL) no grupo de comparação; essa diferença é considerada estatisticamente significante (P = 0,041). Não houve diferença estatisticamente significante entre as médias de idade dos dois grupos. Não houve associação estatisticamente significante entre insuficiência/deficiência de 25(OH)D e tempo de diagnóstico, atividade de doença (SLEDAI > 6), fadiga, uso de corticosteroides e de antimaláricos e anti-DNA. CONCLUSÕES:Foi constatada alta prevalência de insuficiência/deficiência de 25(OH)D nos pacientes com LES (57,7 por cento), com diferença estatisticamente significante em relação ao grupo de comparação. Não evidenciamos associação de insuficiência/deficiência de vitamina D com as variáveis clínicas e laboratoriais estudadas. Os autores enfatizam a importância da determinação dos níveis séricos de 25(OH)D em todos os pacientes com LES, independente de onde residam e do tempo de diagnóstico da doença.

INTRODUCTION: The immunoregulatory role of vitamin D has been the object of a growing number of studies in patients with systemic lupus erythematosus (SLE). OBJECTIVES: To determine the serum levels of 25-hydroxyvitamin D3 [25(OH) D] in patients with SLE, and to assess the association of 25(OH)D insufficiency/deficiency with clinical parameters and laboratory tests. METHODS: Cross-sectional, prospective study performed at the SLE Clinic, Department of Rheumatology, Hospital das Clínicas, Universidade Federal de Pernambuco with convenience sampling, including 78 patients with SLE and 64 volunteers (comparison group), matched by gender and age. RESULTS: Insufficiency/deficiency of 25(OH)D was found in 45 (57.7 percent) patients with SLE and 25 (39 percent) individuals in the comparison group. The mean serum levels of 25(OH)D were 29.3 ng/mL (6.1-55.2 ng/mL) in patients with SLE and 33.12 ng/mL (15.9-63.8 ng/mL) in the comparison group, and this difference was statistically significant (P = 0.041). No statistically significant difference was observed between the mean ages of both groups. No statistically significant association was observed between 25(OH)D insufficiency/deficiency and the following: time to diagnosis; disease activity (SLEDAI > 6); fatigue; use of corticosteroids and antimalarials; and anti-DNA. CONCLUSIONS: High prevalence of 25(OH)D insufficiency/deficiency was found in patients with SLE (57.7 percent), with statistically significant difference as compared with the comparison group. No association of vitamin D insufficiency/deficiency was observed with the clinical variables and laboratory tests studied. The authors emphasize the importance of determining 25(OH)D serum levels in all patients with SLE, regardless of where they live and time to disease diagnosis.

Manifestaciones clínicas y cambios en la química sérica y tisular en ratas tratadas con vitamina D3 (calciferol) / Clinical signs and changes in serum and tissue chemistry in rats treated with vitamin D3 (calciferol)

En el presente trabajo se estudió el efecto de la administración subcutánea de 250, 500 y 750 μg (10.000, 20.000 y 30.000 UI, respectivamente) de vitamina D3 (calciferol)/día durante 8 días, sobre las concentraciones séricas de vitamina D3 y de 25-hidroxivitamina D3 (25-OH-D3) y sobre las concentraciones séricas y tisulares de Ca, Zn, Cu y Fe en 45 ratas macho Wistar, de 12 semanas de edad y con pesos entre 180 y 200 gramos. El grupo control estuvo integrado por 15 ratas Wistar sanas, con género, edad y peso similares a los animales tratados. La administración del calciferol a dosis altas produjo una hipervitaminosis D que se caracterizo por un aumento en el contenido sérico de la vitamina D3 y de 25-OH-D3, diversos signos clínicos (por ejemplo, anorexia, pérdida marcada de peso, diarreas sanguinolentas, conjuntivitis bilateral y muerte), hipercalcemia, hipocincemia, hipercupremia, hipoferremia y una alteración en la distribución tisular de Ca, Zn, Cu y Fe en comparación con los controles no tratados. La hipercalcemia y la inflamación son un hallazgo prominente en la hipervitaminosis D. La inflamación o la infección inducen cambios sistémicos, conocidos colectivamente como la respuesta de fase aguda. Entre las variadas alteraciones que produce esta respuesta encontramos hipoferremia, hipocincemia e hipercupremia. Es probable que estas respuestas estén mediadas, en parte, por la producción y liberación de citocinas como la interleucina 1, interferones (IFN-alfa), la interleucina 6 (Il-6) y el factor de necrosis tumoral (TNF). El desarrollo de la hipoferremia durante la inflamación requiere de hepcidina, un péptido rico en enlaces disulfuro, regulador del metabolismo del hierro, sintetizado en el hígado en respuesta a la liberación de Il-6 durante la inflamación/infección. En conclusión, nuestros resultados proporcionan evidencias que la administración de altas dosis de vitamina D, a corto plazo, determina diversos signos clínicos, produce un marcado aumento de las concentraciones séricas de la vitamina D3 y de 25-OH-D3 y una marcada alteración en las concentraciones séricas y tisulares de Ca, Zn, Cu y Fe, que dependen de las dosis inyectadas de vitamina D.

In the present work the effect of subcutaneous administration of 250, 500 and 750 ìg (10.000, 20.000 and 30.000 IU, respectively) of vitamin D3 (calciferol) daily for eight days, on serum concentrations of vitamin D3 and 25- hydroxyvitamin D3 (25-OH-D3) and on serum and tissue concentrations of Ca, Zn, Cu and Fe in 45 white male Wistar rats, aged 12 weeks and weighing 180-200 g, have been studied. The group control was integrated by 15 healthy rats with similar characteristics (strain, gender, age and weight) that treated animals. Administration of high doses of calciferol produced a hypervitaminosis D characterized by a significant (p3 and 25-OH-D3, diverse clinical signs (such as, anorexia, marked loss of body weight, bloody diarrhea, bilateral conjunctivitis, and death), hypercalcemia, hypozincaemia, hypercupremia, hypoferraemia and an alteration in the tissue distribution of Ca, Zn, Cu and Fe as compared with untreated controls. Hypercalcemia and inflammation are prominent findings in hypervitaminosis D. Inflammation or infection induce systemic changes, collectively known as the acute phase response. Among the varied alterations that together produce this response are hypoferraemia, hypozincaemia and hypercupremia. It is likely that these responses are mediated, in part, by production and release of cytokines such as interleukin 1, interferons (IFN-alpha), interleukin 6 (Il-6) and tumor necrosis factor (TNF). The development of hypoferraemia during inflammation requires hepcidin, an iron regulatory hormone, a disulfide-rich peptide, produced in the liver in response to the release of Il-6 during inflammation/ infection. In conclusion, our results provide evidence that short-term administration of high doses of vitamin D determined diverse clinical signs and produced a marked increase of serum vitamin D3 and 25-OH-D3 and a marked alteration in the serum and tissue concentrations of Ca, Zn, Cu, and Fe. These changes depend on the doses given of vitamin D.

Níveis séricos de 25-hidroxi vitamina D em pacientes portadores de insuficiência renal crônica em tratamento dialítico / 25-hydroxy vitamin D levels in chronic kidney disease patients on dialysis therapy

JUSTIFICATIVA E OBJETIVOS: A contribuição da deficiência de vitamina D para o desenvolvimento do hiperparatireoidismo secundário e da osteodistrofia renal motiva a racional suplementação de vitamina D. A sua deficiência tem sido associada,ainda, a elevado risco cardiovascular. O objetivo deste estudo foi descrever os níveis séricos de 25-hidroxi vitamina D em pacientes portadores de insuficiência renal terminal em terapia dialítica.MÉTODO: Dados clínicos e laboratoriais foram coletados em novembro de 2009 em 168 pacientes em terapia dialítica em um único centro. Os níveis séricos de 25-hidroxi vitamina D foram medidos utilizando o método automatizado de imunoensaio desenvolvido por DiaSorin. De acordo com o Kidney Disease Outcomes and Quality Initiative Guidelines, os pacientes foram classificados em três grupos: suficientes (> 30 ng/mL), insuficientes(15 a 30 ng/mL); e deficientes (< 15 ng/mL). A prevalência de deficiência ou insuficiência de vitamina D foi calculada. Para comparar as variáveis foram usados os seguintes testes: Qui-quadrado,Exato de Fisher e t de Student. O coeficiente de correlação de Spearman foi utilizado para variáveis contínuas. O valor de p < 0,05 foi considerado estatisticamente significativo.RESULTADOS: A média ± desvio padrão de 25-hidroxi vitaminaD foi 23,8 ± 13,3 ng/mL. A prevalência de deficiência devitamina D foi de 23,9% e de insuficiência foi de 47,8%. Quando se compararam as diferenças entre homens e mulheres, idade,albumina e fósforo foram inferiores nas mulheres (p < 0,05). Os níveis de 25-hidroxi vitamina D foram significantemente inferiores em pacientes em diálise peritoneal quando comparados aos em hemodiálise (p < 0,05). Na análise univariada houve pequena correlação positiva entre 25-hidroxi vitamina D e Kt/V.CONCLUSÃO: Os níveis de 25-hidroxi vitamina D foram baixos nesta população. Estudos prospectivos para avaliar o impacto desta deficiência se fazem necessários.(AU)

BACKGROUND AND OBJECTIVES: The contribution of vitamin D deficiency to the development of secondary hyperparathyroidism and renal osteodystrophy contributes the rationale for vitamin D supplementation. Vitamin D deficiency has been associated with elevated cardiovascular risk. This study aimed investigates the serum levels of vitamin D among patients undergoing dialysis.METHOD: In November 2009, we examined clinical and laboratory data from 168 patients in dialytic therapy in a unit. Serum level of vitamin D was included in laboratory data. Serum levels of vitamin D were measured using an automated, antibody and microparticle, chemiluminescence immunoassay method developedby DiaSorin. According to the Kidney Disease Outcomes and Quality Initiative guidelines, patients were assigned to thefollowing 3 groups: sufficient vitamin D serum level (> 30 ng/mL), insufficient level (15 to 30 ng/mL) and with severe deficiency(< 15 ng/mL). Prevalence of deficiency or insufficiency of vitamin D was calculated. To compare the variables were usedthe Chi-square, Fisher Exact or Student's t tests. Spearman correlation coefficient was used for continuous variables. A p value < 0.05 was considered statistically significant.RESULTS: Patient's serum vitamin D mean level was 23.8 ± 13.3 ng/mL. Prevalence of vitamin D deficiency was 23.9%. Prevalence of vitamin D insufficiency was 47.8%. When compared differences between men and women, age, albumin and phosphorus were inferior in women (p < 0.05). Levels of vitamin D were greatly inferior in peritoneal dialysis when compared with hemodialysis (p < 0.05). In the univariate analysis there were weak positive correlations between vitamin D and Kt/V.CONCLUSION: Serum vitamin D levels in this population were low. Prospective studies to assess the impact of low level of vitamin D in patients undergoing dialysis are warranted.(AU)

Nutritional Status of Vitamin D and the Effect of Vitamin D Supplementation in Korean Breast-fed Infants

We investigated the vitamin D status and the effect of vitamin D supplementation in Korean breast-fed infants. The healthy term newborns were divided into 3 groups; A, formula-fed; B, breast-fed only; S, breast-fed with vitamin D supplementation. We measured serum concentrations of vitamin D (25OHD3), calcium (Ca), phosphorus (P), alkaline phosphatase (AP), intact parathyroid hormone (iPTH) and bone mineral density (BMD) at 6 and 12 months of age. Using questionnaires, average duration of sun-light exposure and dietary intake of vitamin D, Ca and P were obtained. At 6 and 12 months of age, 25OHD3 was significantly higher in group S than in group B (PS>B), but total intake of Ca and P were higher in group A than in group B and S (P<0.001). In conclusion, breast-fed infants show lower vitamin D status and bone mineralization than formula-fed infants. Vitamin D supplementation (200 IU/day) in breast-fed infants increases serum 25-OH vitamin D3, but not bone mineral density.

[Hypovitaminosis D in Tunisian osteoporotic post menopausal women and its relationship with bone fracture]

The purpose of this study is to evaluate the frequency of hypovitaminosis D in Tunisian osteoporotic women and to search an eventual association between vitamin D status and the fracture risk. A transverse descriptive study enrolled 134 osteoporotic menopausal women aged 50 years or more. We measured calcium, phosphorus, albumin, alkaline phosphatase, creatinine and 25 hydroxyvitamin D [25 [OH] vit D]. Bone mineral density [BMD] was measured for all and osteoporotic women were defined for a T-score of -2,5 or less in the spine, hip or femoral neck .Two groups were defined: G1 with fracture and G2 without fracture .We used SPSS 10.5, X2 tests and a statistical significance level of p< 0,05. Women in G1 [n= 102] were more aged than those in G2 [n= 32] and their menopause was more ancient. Hypovitaminosis D was found in 45,2% of all women, respectively in 50,98% of G1 and 25% of G2. The mean level of vitamin D was more important in G2 [27,5+ 15,1 vs 21,3 + 12,8 ng/ml; p=0,002]. BMD in femoral and lumbar were statistically lower when fractures are present [p< 0,001]. Our study shows that women with hypovitaminosis D [vit D < 20 ng/ml] are prone to osteoporotic fractures. All fracture in community in menopausal women, should be assessed with BMD and screening for 25 [OH] vit D. Increasing life expectancy in our country suggests that this public health problem will grow in the years to come, pointing out the importance of better management of osteoporosis and hypovitaminosis D to prevent fractures

Iranian diabetics may not be vitamin D deficient more than healthy subjects

There are some reports of decreased serum levels of 25[OH]D in the subjects with impaired glucose tolerance and type 2 diabetes mellitus [T2DM]. To assess vitamin D status of the Iranian diabetics, a pilot study was conducted on 90 subjects with either type 1 diabetes mellitus [T1DM] [n= 30], T2DM [n= 30], or apparently healthy subjects [n= 30] during fall and winter of 2005. Serum samples were analyzed for 25-hydroxycholecalciferol using three different methods: high-performance liquid chromatography [HPLC], competitive protein-binding assay [CPBA] and radioimmunoassay [RIA]. In this study serum levels of 25[OH]D were categorized as follows: sufficient. 37 nmol/L; 25 nmol/L. mild deficiency < 37 nmol/L; 12.5 nmol/L. moderate deficiency < 25 nmol/L; severe deficiency < 12.5 nmol/L. Results showed that the occurrence of vitamin D insufficiency was almost the same in patients with T1DM and healthy controls. Mean serum level of 25[OH]D in patients with T2DM was significantly higher than in T1DM, as judged by HPLC [58.2'] 8.5 vs. 35'] 5 nmol/L, Mann Whitney U-Wilcoxon, P= 0.024]. Moreover, both CPBA and RIA showed some over-estimation of serum 25[OH]D compared to HPLC. Our findings suggest that, at least in the cold seasons, vitamin D status of the healthy subjects may not be higher than that of T1DM patients

Correlation between serum vitamin D (25(OH)D) concentration and quadriceps femoris muscle strength in Indonesian elderly women living in three nursing homes.

AIM: to investigate the correlation between serum vitamin D (25(OH)D) concentration and quadriceps femoris muscle strength. METHODS: this was a cross-sectional correlative study, conducted at three nursing homes in Jakarta and one nursing home in Bekasi in January 2005. The subjects were women aged 60 years or above. Those selected study subjects underwent quadriceps femoris muscle strength examination with Cybex dynamometer with 150 degrees/second speed, twice (three repetitions with 30 second rest time). The 25 (OH)D concentration was measured by ELISA. RESULTS: out of 67 subjects who met the required criteria for this study, five subjects withdrew from the study during muscle strength examination. The mean age was 71.1 (SD 7.2) years old while the mean serum vitamin D concentration was 68.2 (SD 21.6) nmol/l. Vitamin D deficiency (<or= 50 nmol/l) was found in 22.6% of subjects. It was also found that the median (minimum-maximum) quadriceps femoris muscle strength was 40.00 (11-116) N.m. Approximately 82.3% of the subjects were of generalized muscle weakness. Correlation was found between serum 25 (OH)D concentration and quadriceps femoris muscle strength (r = 0.327; P = 0.009). CONCLUSION: this study reveals that serum 25 (OH) D concentrations in Indonesian elderly women is correlated with quadriceps femoris muscle strength. The proportion of elderly women with muscle weakness is higher than the normal ones. The group with older age shows higher proportion of muscle weakness. Most subjects have normal serum vitamin D concentration.

Fracturas vertebrales, osteoporosis y vitamina D en la posmenopausia: Estudio en 555 mujeres en Chile / Vertebral fractures, osteoporosis and vitamin D levels in Chilean postmenopausal women

Background: Approximately one-third of vertebral fractures can be clinically diagnosed. Aim: To study the frequency of vertebral fractures in postmenopausal women. Patients and methods: We recruited 555 postmenopausal women from Santiago, Chile, aged 55-84 years, who manifested interest in their bone health. All were healthy by self-declaration and by general clinical and laboratory tests and had not taken any bone-active therapy. They all underwent a spine and femoral neck (FN) densitometry and a digital lateral spine X-ray from T4 to L4 was obtained. PTH, calcidiol, and other parameters of calcium metabolism were also measured. Results: Overall, 142 of 478 patients with a complete study (29.7 percent) had at least one vertebral fracture. The proportion of women with fractures increased with age. A T score below -2.5 in the spine and hip was found in 32 percent and 14 percent of women, respectively. The proportion of women with spinal opeoporosis doubled between ages 55-70 and remained constant afterwards. In contrast, at the femoral neck, this proportion increased progressively reaching 53.3 percent at age 80-85. However, 56 percent of patients with vertebral fractures did not have densitometric osteoporosis in any location. Calcidiol levels were 16.8±6.8 ng/mL. With a cutoff point of 17 ng/mL, 47.5 percent of the patients had hypovitaminosis D. There was no association between calcidiol levels and vertebral fractures or bone density at the spine or femoral neck. Patients with fractures differed from those without fractures in that they had significantly lower bone density at the spine and hip and were older (p <0.001). However they did not differ in weight, body mass index, or calcidiol levels. Conclusions: Thirty percent of postmenopausal women in this series had a vertebral fractures. Osteoporosis and vitamin D deficiency were also common. Most vertebral fractures were observed in women without osteoporosis by densitometric criteria.

Vitamin D status in pregnant and their newborns

Adequate vitamin D concentrations during pregnancy are necessary for neonatal calcium homeostasis, bone maturation and mineralization. The purpose of this study was to evaluate serum vitamin D in mothers and their newborns. This study comprised 552 pregnant women from Tehran University hospitals. Maternal and cord blood samples were obtained in delivery room just after child birth. The serum samples were assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone. Prevalence of vitamin D deficiency in mothers and cord blood were 66.8% and 93.3% [<35nmol/l] respectively. There was a significant correlation between maternal and cord blood levels of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D levels were lower than those of normal mothers [p=0.001]. Furthermore, considering increased requirements of calcium and vitamin D during pregnancy; intake of higher amounts of these nutrients are recommended

Difference in serum calcidiol and parathyroid hormone levels between elderly urban vs suburban women.

The present study initially included 106 volunteers, elderly women living in urban or suburban Khon Kaen, Thailand. One case was excluded because of extremely high levels of alkaline phosphatase. The means (+/- SD) of the serum calcidiol and the PTH concentrations in the urban vs suburban groups were 31.45(+/- 1.15) ng/mL vs 36.15(+/- 2.4) pg/mL and 41.53(+/- 3.94) ng/mL vs 17.43(+/- 2.88)pg/mL, respectively. The urban group had a higher percentage and a higher risk of hypovitaminosis D and osteoporosis of the femoral neck than the suburban group, an odds ratio of more than 4 times higher.