Vitamina D y embarazo: una experiencia piloto / Vitamin D and pregnancy: a pilot experience

La insuficiencia de vitamina D (VD) en el embarazo se relaciona con una mayor incidencia de cesáreas, preeclampsia y partos prematuros. Objetivo: evaluar si el grado de insuficiencia de VD se asocia a mayor número de cesáreas y evaluar la correlación entre la 25 hidroxivitamina D (25OHD) materna y en sangre del cordón del recién nacido. Las mujeres (n=127) se dividieron según sus niveles de 25OHD (ng/mL):G1:<20 (deficiencia), G2:20-30 (insuficiencia), G3:>30 (suficiencia). Se registraron edad; edad gestacional (EG); índice de masa corporal (IMC); tensión arterial sistólica y diastólica; tipo de parto y la estación del año en que se tomó la muestra. Se determinaron calcemia (ng/mL); 25OHD; parathormona intacta (pg/mL); fosfatasa alcalina ósea (UI/L) y crosslaps (pg/mL). La edad media fue de 26±6 años y la EG de 35,8±2,7 semanas, sin diferencias entre grupos. El porcentaje de cesáreas fue mayor en G1 que en G2 y G3 (31,3%, 21,4% y 25%, respectivamente; p<0,05). El mayor porcentaje de muestras se tomó en primavera (p<0,05). No se observaron diferencias en las demás variables maternas estudiadas. La 25OHD materna correlacionó positivamente con los valores de la sangre de cordón de sus respectivos recién nacidos (r= 0,67; p<0,0001). Independientemente de la época del año y del IMC, se observó que un porcentaje significativo de las mujeres embarazadas estudiadas tenía niveles de 25OHD inferiores a 30 ng/mL. Conclusión: evidenciamos que la deficiencia de VD materna se asoció al número de cesáreas. Asimismo, los niveles séricos de 25OHD en sangre de cordón umbilical correlacionaron significativamente con los maternos. (AU)

Vitamin D (VD) insufficiency in pregnancy is associated with a higher incidence of cesarean section, preeclampsia, and preterm delivery. Objective: to evaluate if the degree of VD insufficiency is associated with the incidence of cesarean section and to determine the correlation between maternal and newborn cord blood 25-hydroxy VS (25OHD). Women (n=127) were divided according to their 25OHD levels (ng/mL): G1:<20 (deficiency), G2:20-30 (insufficiency), G3:>30 (sufficiency). Age; gestational age (GA); body mass index (BMI); systolic and diastolic blood pressure (mmHg); type of delivery and the season of the year in which the sample was taken were recorded. Calcemia (ng/mL); 25OHD; intact parathormone (pg/mL); bone alkaline phosphatase (IU/L) and Crosslaps (pg/mL) levels were determined. Mean age was 26±6 years and GA was 35.8±2.7 weeks with no differences among groups. The % of cesarean sections was higher in G1 than in G2 and G3 (31.3%, 21.4% and 25%; p<0.05). The highest % of samples were taken in spring (p<0.05). No differences were observed in the other maternal variables studied. Maternal serum 25OHD levels correlated positively with those of cord blood from their respective newborns (r=0.67; p<0.0001). Regardless the season of the year and BMI, a high % of the studied pregnant women presented 25OHD levels lower than 30 ng/ml. Conclusion: we found that maternal VD deficiency is associated with the number of cesarean sections. In addition, 25OHD levels in the newborn significantly correlate with maternal serum levels. (AU)

The importance of optimal 25-hydroxyvitamin D levels in the glycemic control of older adults with type 2 Diabetes Mellitus: Data from the study on aging and longevity EELO

INTRODUCTION: Optimal serum levels of vitamin D are of great importance, especially in populations with comorbidities such as Diabetes Mellitus (DM). OBJECTIVE: The study evaluated the relationship between hypovitaminosis D and glycemic control in older adults with type 2 DM. METHODS: Cross-sectional and prospective study, part of the EELO project (Study on Aging and Longevity), conducted in Southern Brazil. Glycated hemoglobin (diabetes ≥6.5%) and serum levels of vitamin D (25(OH)D) were evaluated. Hypovitaminosis D was determined using cutoff points <20 and <30 ng/mL). Multivariate logistic regression was used to assess the risk of having uncontrolled DM. RESULTS: Of the 120 older adults included in the study, aged between 60 and 87 years, 74.2% were women, 66.7% used hypoglycemic medications and 75.8% exhibited uncontrolled diabetes. An inverse correlation was observed between the levels of 25(OH) D and glycated hemoglobin (rS=-0.19, p=0.037), suggesting that low levels of vitamin D are associated with poor glycemic control in diabetic individuals. The prevalence of hypovitaminosis D when using the cutoff points of <20 and <30 ng/mL were 34.2% and 75.0%, respectively. The odds ratio (OR) analysis showed that individuals with 25(OH)D<20ng/mL have almost 4 times more risk of having uncontrolled DM (OR:3.94; CI95%:1.25-12.46, p=0.02) when compared to the older adults with sufficient levels of vitamin D. CONCLUSION: The results indicate that the optimal serum levels currently recommended for 25(OH)D should preferably be 30 ng/mL or higher to contribute to better glycemic control in older adults with type 2 DM.

INTRODUÇÃO: Os níveis séricos ideais de vitamina D são de grande importância, especialmente na população com comorbidades como o Diabetes Mellitus (DM). OBJETIVO: O estudo avaliou a relação entre hipovitaminose D e controle glicêmico em idosos com DM tipo 2. MÉTODOS: Estudo transversal e prospectivo, parte do projeto EELO (Estudo sobre Envelhecimento e Longevidade), no Sul do Brasil. A hemoglobina glicada (diabetes ≥6,5%) e os níveis séricos de vitamina D (25(OH)D) foram avaliados. Hipovitaminose D foi determinada usando ponto de corte <20 e <30 ng/mL. Regressão logística multivariada foi utilizada para avaliar o risco de ter DM descompensado. RESULTADOS: Dos 120 idosos incluídos no estudo, idade entre 60 a 87 anos, 74,2% eram mulheres, 66,7% faziam uso de medicamentos hipoglicemiantes e 75,8% apresentavam diabetes descompensada. Uma correlação inversa foi observada entre os níveis de 25(OH)D e hemoglobina glicada (rS=-0,19; p=0.037), sugerindo que baixos níveis de vitamina D está associado a um pior controle glicêmico em diabéticos. A prevalência de hipovitaminose D quando se utiliza ponto de corte <20 e <30 ng/mL foi de 34,2% e 75,0%, respectivamente. A análise Odds ratio (OR) mostrou que indivíduos com 25(OH)D<20 ng/mL tem quase 4 vezes mais risco de ter DM descompensado (OR:3,94; IC95%:1,25­12,46; p=0,02) quando comparado aos idosos com níveis suficientes de vitamina D. CONCLUSÃO: Os resultados indicam que os níveis sérios ideais atualmente recomendados para 25(OH)D maior ou igual a 30 ng/ml contribuem para o melhor controle glicêmico na população idosa com DM tipo 2.

Are Serum Vitamin D Levels Associated With Dry Eye Disease? Results From the Study Group for Environmental Eye Disease / 예방의학회지

OBJECTIVES: Dry eye disease (DED) is an increasingly important public health problem in Korea. Previous studies conducted in Korea have reported inconsistent results regarding the protective effects of vitamin D on DED, and these discrepancies may be related to the relatively simple questionnaire that has been used. Thus, we evaluated the association of serum vitamin D levels with DED using the ocular surface disease index (OSDI). METHODS: The present study evaluated data from participants in the Study Group for Environmental Eye Disease (2014-2015). This group included data from 752 participants, and data from 740 participants (253 men and 487 women) were analyzed in the present study. DED severity was evaluated using the OSDI. RESULTS: Higher serum vitamin D levels were associated with a non-significantly reduced risk of DED in the crude analysis (odds ratio [OR], 0.991; 95% confidence interval [CI], 0.971 to 1.011) and in the adjusted analysis (OR, 0.988; 95% CI, 0.966 to 1.010). In the crude analysis of no/mild DED vs. moderate/severe DED, men exhibited a decreased risk with increasing serum vitamin D levels (OR, 0.999; 95% CI, 0.950 to 1.051), while women exhibited an increased risk (OR, 1.003; 95% CI, 0.979 to 1.027). In these analyses, we found no significant associations. CONCLUSIONS: The findings of the present study support previous reports that serum vitamin D levels are not associated with DED.

Impact of vitamin d on development of early childhood caries

Objective: To compare the levels of vitamin D in children with early childhood caries and children with healthy sound dentition

Study Design: Cross sectional study

Place and Duration of study: The study was conducted at Islamic International Medical College from September 2015 to March 2016

Material and Methods: Eighty children, between 2-8 years of age, were recruited after fulfilling a questionnaire from their parents or care giver. The sample population was divided into two groups. Group 1 consisted of children suffering from dental caries and was comprised of 60 patients. Group 2 consisted of children with sound healthy teeth and was comprised of 20 children. Questions assessing children s socioeconomic background, dietary habits particularly frequency of sweet and milk intake, outdoor activity and dental hygiene related behavior were included. The diagnosis of childhood caries was based on oral health diagnostic criteria defined by World Health Organization [WHO] Overall total caries score [decayed missing filled teeth index] was obtained

Levels of 25-hydroxyvitamin D [25[OH] D] was measured from serum samples of the children participating in this study using enzyme linked immunosorbent assay [ELISA]. Correlation analysis was done with Pearson correlation and t-test was applied

Results: Results have established association of Vitamin D levels in children with early childhood caries. Pearson correlation and t-test have revealed that total decayed, missing, filled primary teeth [dmft] caries score was also associated with 25[OH] D concentrations less than 30ng/ml, decreased oral hygiene, lower monthly income, increased sugar consumption, decreased milk intake and decrease outdoor activities. This cross-sectional study showed that carries and lower serum vitamin D are closely related with each other

Conclusion: Data from this cross-sectional study showed that dental caries and lower serum vitamin D were closely related. Improving children's vitamin D status may be an additional preventive consideration to lower the risk for caries

Hypovitaminosis D in Children with Hashimoto’s Thyroiditis / Hipovitaminosis D en niños con tiroiditis de Hashimoto

Background: Vitamin D deficiency or insufficiency may play a role in the pathogenesis of certain autoimmune diseases. Aim: To measure vitamin D levels in children with Hashimoto’s thyroiditis (HT) (either with subclinical or marked hypothyroidism) and in healthy controls. Material and Methods: We included 68 children with HT aged 12 ± 4 years (39 females) from a pediatric outpatient clinic and 68 healthy children aged 10 ± 4 years (37 females). Calcium metabolism parameters, thyroid function tests and anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-TG) and 25 hydroxy vitamin D (25OHD) levels were measured. Results: Patients were older than controls but well matched by gender distribution. Mean 25OHD levels were significantly lower in HT patients than controls (16.8 ± 9.3 and 24.1 ± 9.4 ng/mL respectively, P < 0.01). Frequency of vitamin D deficiency was 76 and 35% in HT patients and controls, respectively (P < 0.001). Conclusions: Vitamin D deficiency is more common in children with HT than healthy controls.

Antecedentes: La deficiencia o insuficiencia de vitamina D puede tener un rol en la patogenia de enfermedades autoinmunes. Objetivo: Medir niveles de vitamina D en niños con tiroiditis de Hashimoto (TH) (con hipotiroidismo subclínico o marcado) y en controles sanos. Material y Métodos: Estudiamos 68 niños con TH, de 12 ± 4 años (39 mujeres) y 68 controles sanos de 10 ± 4 años (37 mujeres). Se les midió parámetros de metabolismo de calcio, pruebas de función tiroidea, anticuerpos anti peroxidasa y anti tiroglobulina y 25 hidroxi vitamina D (25 OH vit D). Resultados: Los pacientes eran mayores que los controles pero la distribución por género era homogénea en ambos grupos. Los niveles de 25 OH vit D en pacientes y controles fueron 16,8 ± 9,3 y 24,1 ± 9,4 ng/mL respectivamente, p < 0,01. La frecuencia de deficiencia de vitamina D fue de 76 y 35% en pacientes y controles, respectivamente. Conclusiones: La deficiencia de vitamina D es más común en niños con TH.

Interaction of Vitamin D and Smoking on Inflammatory Markers in the Urban Elderly / 예방의학회지

OBJECTIVES: Epidemiological studies have reported that vitamin D deficiency is associated with inflammatory disease. Smoking is a well-known risk factor for inflammation. However, few studies have investigated the interactive effect of vitamin D deficiency and smoking on inflammation. This study aims to investigate the interaction of vitamin D and smoking with inflammatory markers in the urban elderly. METHODS: We used data from the Korean Elderly Environmental Panel Study, which began in August 2008 and ended in August 2010, and included 560 Koreans > or =60 years old living in Seoul. Data was collected via questionnaires that included items about smoking status at the first visit. Vitamin D levels, high-sensitivity C-reactive protein (hs-CRP), and white blood cell (WBC) counts were repeatedly measured up to three times. RESULTS: The association of vitamin D and hs-CRP was significant after adjusting for known confounders (beta=-0.080, p=0.041). After separate analysis by smoking status, the association of vitamin D deficiency and hs-CRP in smokers was stronger than that in nonsmokers (smokers: beta=-0.375, p=0.013; non-smokers: beta=-0.060, p=0.150). Smoking status was an effect modifier that changed the association between vitamin D deficiency and hs-CRP (interaction estimate: beta=-0.254, p=0.032). Vitamin D was not significantly associated with WBC count (beta=0.003, p=0.805). CONCLUSIONS: Vitamin D deficiency was associated with hs-CRP in the urban elderly. Smoking status was an effect modifier of this association. Vitamin D deficiency was not significantly associated with WBC count.

Fractures; causes of low vitamin D and effects of 25 [oh] supplementation in patients above 50 years

To find out the effect in increase in serum 25 [OH] vitamin D levels after supplementation with 1000 lU/day of vitamin D in patients with low vitamin D levels and other factors which may affect the increase in vitamin D levels. Retrospective study. January 2013 and June 2014. Ch. Rehmat Ali Trust Teaching Hospital in the Lahore. The study included patients > 50 years with a low-energy fracture and a vitamin D level < 25 nmol/l. 85 patients were included, mean basal 25 [OH] vitamin D level was 22 nmol/l. After a mean of 10 weeks, the mean increase in vitamin D was 49.5 nmol/l. Only 45.1% reached the target level of > 50 nmol/l. The increase was correlated with the basal level of vitamin D [p < 0.05], and the time interval between the two vitamin D measurements [p < 0.05] and was inversely related to body weight [p < 0.05], but was not related to age, gender or renal function. We found that the generally recommended dosage of 1000 IU of vitamin D per day resulted in suboptimal serum levels after ten weeks of treatment in more than half of the patients. The increase in vitamin D levels was higher in patients with low body weight and in patients with very low basal vitamin D levels. These data suggest that these patients should initially be treated with higher dosages of vitamin D. If not possible, vitamin D measurements should be performed after at least six months of supplementation with dosage adjustment

Efficacy of the Measurement of 25-Hydroxyvitamin D2 and D3 Levels by Using PerkinElmer Liquid Chromatography-Tandem Mass Spectrometry Vitamin D Kit Compared With DiaSorin Radioimmunoassay Kit and Elecsys Vitamin D Total Assay

No abstract available.

Vitamin D Receptor Poly(A) Microsatellite Polymorphism and 25-Hydroxyvitamin D Serum Levels: Association with Susceptibility to Breast Cancer / 한국유방암학회지

PURPOSE: According to previous studies, vitamin D exhibits protective effects against breast cancer via the vitamin D receptor (VDR). There is growing evidence that breast cancer incidence is associated with various polymorphisms of the VDR gene. This study investigates the association of VDR poly(A) microsatellite variants with 25-hydroxyvitamin D (25(OH)D) serum levels and breast cancer risk. METHODS: Polymorphism analysis was performed on a total of 261 blood samples, which were collected from 134 women with breast cancer and 127 controls. Single strand conformation polymorphism was assessed by polymerase chain reaction in combination with sequencing to detect poly(A) lengths for each sample. The vitamin D levels of samples were determined by electrochemiluminescence. RESULTS: The poly(A) variant L allele frequency was significantly higher in cancer patients than in controls (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.16-2.57; p=0.006). Thus, carriers of the L allele (LS and LL genotypes) have a higher risk for breast cancer (OR, 1.86; 95% CI, 1.13-3.05; p=0.013). A larger increase in the risk for breast cancer was found in individuals with the L carrier genotype and lowered 25(OH)D levels. CONCLUSION: The results primarily suggest that VDR gene polymorphism in the poly(A) microsatellite is associated with 25(OH)D levels and that it can affect the breast cancer risk in the female population from northern Iran.

Assessment of low vitamin D among Saudi Arabians. Did we overshoot the runway?

To compare the performance of 3 commonly used 25-hydroxyvitamin D [25-OHD] assays among a sample of the Saudi population. This cross-sectional study was carried out between January 2011 and December 2012 at King Fahd Hospital of the University, Al-Khobar, Saudi Arabia. After informed consent, blood samples for measurement of 25-OHD level was extracted from 200 adults. The vitamin D level of each individual were determined using chemiluminescence immunoassay [CLIA], radio-immuno assay [RIA], and liquid chromatography-tandem mass spectrometry [LC-MS/MS] assay. Assays were also compared through commonly used cut-points for classification of vitamin D deficiency. Bias between assays was evaluated using Bland-Altman plots. The average age of patients was 45.7 +/- 16.1 years. A significant difference between the assays was found. The mean 25-OHD levels were highest for the LC-MS/MS [21.65 ng/mL, 95% CI 19.74-23.56], intermediate for RIA [16.607 ng/mL, 95% CI 14.87-18.32], and lowest for CLIA method [13.864 ng/mL, 95% CI 12.109-15.618]. Using 30 ng/mL as a cutoff value, only 6% was found to have normal levels of 25-OHD using CLIA, 9% using RIA, and 22% using LC-MS/MS. Levels of 25-OHD and the prevalence of vitamin D deficiency are dependent on the assay used. The reported high prevalence of hypovitaminosis D among the Saudi population can be partially explained by the use of assays that underestimate vitamin D levels

Vitamin D enhances IL-1 beta secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients

The emergence of multidrug-resistant strains of Mycobacterium tuberculosis [MTB], the bacterium responsible for tuberculosis [TB], has rekindled the interest in the role of nutritional supplementation of micronutrients, such as vitamin D, as adjuvant treatment. Here, the growth of virulent MTB in macrophages obtained from the peripheral blood of patients with and without TB was studied. The H37Rv strain genetically modified to express Vibrio harveyi luciferase was used to determine the growth of MTB by luminometry in the human monocyte-derived macrophages [hMDMs] from study subjects. Determination of cytokine levels in culture supernatants was performed using a flow cytometry-based bead array technique. No differences in intracellular growth of MTB were observed between the different study groups. However, stimulation with 100 nM 1,25-dihydroxyvitamin D significantly enhanced the capacity of hMDMs isolated from TB patients to control the infection. This effect was not observed in hMDMs from the other groups. The interleukin [IL]-1 beta and IL-10 release by hMDMs was clearly increased upon stimulation with 1,25-dihydroxyvitamin D. Furthermore, the 1,25-dihydroxyvitamin D stimulation also led to elevated levels of TNF-alpha [tumor necrosis factor-alpha] and IL-12p40. It was concluded that vitamin D triggers an inflammatory response in human macrophages with enhanced secretion of cytokines, as well as enhancing the capacity of hMDMs from patients with active TB to restrict mycobacterial growth

Performance Evaluation of Method for Detecting Serum 25-Hydroxyvitamin D2 and 25-Hydroxyvitamin D3 by Using PerkinElmer MSMS Vitamin D Kit / 임상검사와정도관리

BACKGROUND: Determining the concentration profiles of serum 25-hydroxyvitamin D (25OHD) may aid in the clinical diagnosis and treatment of vitamin D deficiency. To date, the standardized liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been used for accurate and precise determination of 25-hydroxyvitamin D levels. Here, we evaluated the performance of the recently developed and introduced PerkinElmer Vitamin D kit and compared the measurements obtained by RIA and LC-MS/MS methods. METHODS: We evaluated the accuracy, precision, linearity, lower limit of quantification (LLOQ), recovery, and carry-over of the MSMS Vitamin D kit. Clinical specimens from 80 patients were used for the comparison between the MSMS Vitamin D kit (PerkinElmer, USA) and the RIA kit (DiaSorin, USA). RESULTS: The MSMS Vitamin D kit was found to produce intra-assay and inter-assay coefficients of variation (CVs) of less than 6% for precision and showed a bias of less than 5%. The MSMS Vitamin D kit displayed linearity within the range for total vitamin D levels of 4.5-150 ng/mL, and the lower limit of quantification for 25OHD was 0.38 ng/mL. The RIA measurements of 25OHD showed a correlation of y=0.9931x+0.2216 (r2=0.74) with the LC-MS/MS values. CONCLUSIONS: The LC-MS/MS assay of 25OHD3 and 25OHD2 showed excellent performance when using the MSMS Vitamin D kit and in terms of 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) derivatization. Further, the results obtained were well correlated with those obtained using the RIA method. Thus, assays using the MSMS Vitamin D kit are considered as more standardized, and they enable quicker and more accurate analysis and help reduce inter-laboratory variation than that by other existing methods.

Serum 25 hydroxy vitamin D levels in adult asthmatic patients

Patients with chronic lung disease as asthma appear to be at increased risk for vitamin D deficiency for reasons that are not clear. A cross sectional study including 75 asthmatic adults aged older than 18 years and 75 adults healthy control aged older than 18 years [35 males and 40 females for both groups] assessing the relationship between serum 25 hydroxy vitamin D levels and lung function. In our study only [12.31%] of our asthmatic adults had sufficient vitamin D levels [>/=30 ng/ml], wherase [85%] of healthy control subjects expressed sufficient levels. Vitamin D deficiency [<20 ng/ml] was observed in 59 [78.66%] asthmatic patients [17.28 +/- 2.4 ng/ml]. Deficiency was not observed in controls [33.67 +/- 6.3]. In asthmatic patients Serum 25 [OH] vitamin D was positively correlated with forced expiratory volume in 1 second% [FEV1%] predicted andforced expiratory/forced vital capacity ratio [FEV1/FVC][P=<0.05 for all]. There was no significant association between serum vitamin D level and eosinophil count. Reduced vitamin D levels are highly prevalent in adult asthmatic patients and are associated with impaired pulmonary functions

Bone density and bone metabolism in patients with inflammatory bowel disease

Patients with inflammatory bowel disease [IBD] are at high risk for low bone mineral density [BMD]. This study aimed to evaluate BMD in IBD patients and its relationship with bone metabolism in a group of Iranian patients. A cross-sectional study was conducted on patients with IBD to assess BMD status and serum biochemical factors. After getting the demographic data from 200 patients, they were screened using dual-energy X-ray absorptiometry of the lumbar spine [L2-L4] and femoral neck for BMD status. Serum levels of calcium, phosphate, alkaline phosphatase [ALP], and 25-hydroxyvitamin D [25-OH vitamin D] were measured to assess the bone metabolism status. Two hundred patients with IBD were enrolled in the study. One hundred and eighty three [91.5%] patients were identified as having ulcerative colitis [UC] and 17 [8.5%] as having Crohn's disease [CD]. Based on the lumbar and femoral neck bone mass densitometry, 148 [74.4%] patients had low BMD at either lumbar spine or femoral neck. Of these, 100 patients [50.3%] were osteopenic and 48 patients [24.1%] were osteoporotic. A 58.6% and 61% of patients with UC had low BMD in the lumbar and femoral neck, respectively. These results for those with CD were 76.5% and 70.6%, respectively. The mean of femoral neck and lumbar T-scores in patients with UC were -1.14 and -1.38, and in patients with CD were -1.24 and -1.47, respectively [P > 0.05]. The mean [ +/- SD] levels for calcium [Ca] in UC and CD were in the normal range. The mean [ +/- SD] levels of ALP and 25-OH vitamin D in both the groups were in the normal range, and in comparison between groups [UC and CD], no significant differences were observed [P = 0.20 for ALP and P = 0.44 for 25-OH vitamin D]. In the assessment of correlation between biochemical markers and BMD, an inverse correlation between lumbar T-score and ALP or 25-OH vitamin D only in patients with UC was observed. The high prevalence of low BMD in the Iranian population with IBD needs attention. The subclinical vitamin D deficiency may contribute to bone loss in IBD patients, which is more pronounced in patients with UC in this study because of the small population of patients with CD

Measurement of Serum Levels of 25-Hydroxyvitamin D3 and 25-Hydroxyvitamin D2 Using Diels-Alder Derivatization and Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry

BACKGROUND: Vitamin D has been recently shown to play important roles in the functioning of various systems. Most of the current analytical methods for measuring vitamin D levels are based on immunoassays. We simultaneously measured the levels of 25-hydroxyvitamin D3 [ 25(OH)D3 ] and 25-hydroxyvitamin D2 [ 25(OH)D2 ] in human serum by performing ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) after Diels-Alder derivatization with 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) and evaluated the performance of our method. METHODS: After liquid-liquid extraction, samples were dried under N2 at 50degrees C for 1 hr followed by Diels-Alder derivatization with ethyl acetate containing 0.1 mg/mL PTAD. The samples were resuspended in 60 microL of methanol:10 mM ammonium formate solution (1:1, V/V). C18 UPLC column and positive ion multiple reaction monitoring transitions such as m/z 558.35-->298.1, 25(OH)D3; m/z 570.35-->298.1, 25(OH)D2; and m/z 564.35-->298.1, hexadeuterated-25(OH)D3 were used for UPLC-MS/MS. RESULTS: The within-run imprecision (CVs) for 25(OH)D3 and 25(OH)D2 were 3.5-4.0% and 3.8-4.2%, respectively, and the corresponding between-run CVs were 3.3-5.5% and 4.7-5.8%. The lower limit of quantification for 25(OH)D3 and 25(OH)D2 were 0.5 and 1.0 ng/mL, respectively. The curve for interassay calibration variability data obtained over concentrations of 0-120 ng/mL for 25(OH)D3 and 0-90 ng/mL for 25(OH)D2 was linear and reproducible [ 25(OH)D3, R2=0.993; 25(OH)D2, R2=0.998]. The total 25(OH)D levels in Koreans (average, 18.7 ng/mL) were lower than those in American Caucasians, and the percentage of people with total 25(OH)D levels under 10 ng/mL was 8.1%. CONCLUSIONS: Our method to measure 25(OH)D3 and 25(OH)D2 levels by performing UPLC-MS/MS after PTAD derivatization showed good performance as a sensitive and reproducible method for routine analysis of vitamin D status.

Pilot study of sunlight exposure and vitamin D status in Arab women of childbearing age

Vitamin D deficiency is common in Arab women, In a pilot study we investigated the effect of sun exposure at recommended levels on the vitamin D status of Arab women. Eight healthy Arab women of child-bearing age consented to expose their face, arms and hands for 15 minutes per day twice a week for 4 weeks within the privacy of their courtyard and to avoid changes in dietary vitamin D intake. Serum 25-hydroxyvitamin D [25[OH]] levels were measured pre- and post-intervention. Although vitamin D levels remained sub-optimal, median serum 25[OH]D levels were significantly higher post-intervention [23.0 nmol/L] than pre-intervention [17.6 nmol/L]. Extending sun exposure for more than 4 weeks should be investigated as part of strategies to improve vitamin D status in high-risk Arab women who lack outdoor sun exposure to the skin

25-Hydroxyvitamin D Status in Patients with Chronic Kidney Disease in a Single Center / 대한신장학회지

PURPOSE: We checked the levels of serum 25-hydroxyvitmain D (25OHD) in the patients with chronic kidney disease (CKD) to survey the status of vitamin D levels, to see the seasonal variations of 25OHD, and to evaluate the relationships among the levels of intact PTH, corrected calcium, and phosphorus. METHODS: We defined vitamin D insufficiency and vitamin D deficiency as serum 25-hydroxyvitamin D levels between 20 and 30 ng/mL and below 20 ng/mL, respectively. 185 patients in a single center were enlisted who categorized into 3 groups, CKD2-3, CKD4, and CKD5 by eGFR using MDRD7 equation. To see the seasonal differences of the levels of 25OHD, we collected laboratory data two times per each patient during summer division (April to September) and winter division (October to March). RESULTS: Prevalences of hypovitaminosis D were 42.8% (CKD2-3), 66.1% (CKD4), 92.8% (CKD5) in summer division and 48.7% (CKD2-3), 73.1% (CKD4), 92.8% (CKD5) in winter division. Seasonal difference of the levels of 25OHD was evident only in CKD stage 2-3 (p=0.018). Negative correlations were recognized between 25OHD and intact PTH (r=-0.2048, p<0.001), phosphorus (r=-0.1711, p=0.0011). CONCLUSION: Hypovitaminosis D is prevalent even in patients with early stages of CKD. The levels of 25OHD decreased significantly in winter division in patients with CKD stages 2-3. The levels of 25OHD were inversely correlated with those of intact PTH, phosphorus, respectively.

Frequency of fokI and taqI polymorphism of vitamin D receptor gene in Indian population and its association with 25-hydroxyvitamin D levels.

BACKGROUND: The VDR protein is at the centre of the vitamin D endocrine system, a complex physiological system with substantial feedback regulatory mechanisms involved in maintaining serum calcium and 1, 25 dihydroxy vitamin D3. Variations in VDR gene are shown to have implications in several diseases and have also been implicated as an important genetic factor affecting bone mass. AIM: To determine the frequency of Fok I and Taq I variants in healthy Indian individuals and its association with 25-OH-Vitamin D levels. SETTINGS AND DESIGN: Blood samples were collected from 143 unrelated normal individuals (Male-84 and Female-59) and their genotypes determined. MATERIALS AND METHODS: After amplification by polymerase chain reaction, each polymorphism was genotyped by restriction fragment length polymorphism. For 100 normal healthy individuals 25-hydroxyvitamin D estimation was done using DiaSorin kit method. STATISTICAL ANALYSIS: Graph pad software was used to calculate the P values from the Chi-square. RESULTS: Out of 143 samples analyzed for FokI and TaqI polymorphisms the following genotypic frequency was obtained FF 59%, Ff 36%, ff 5% and TT 49%, Tt 43%, tt 8% respectively. CONCLUSIONS: Results indicate that the distribution of the polymorphic loci Fok I and Taq I vary considerably not only in different populations, but also within India. Furthermore, when the genotypes were analyzed with respect to 25-OH-Vitamin D levels, a significant association was seen for the Taq 1 SNP but not with the Fok I.

Current maternal-infant micronutrient status and the effects on birth weight in the United Arab Emirates

Micronutrient deficiencies exist among women of childbearing age in the United Arab Emirates but the effects of maternal micronutrient deficiency on fetal growth are not well documented. To investigate the association between micronutrients and birth weight, we measured maternal and cord blood micronutrients [vitamin A, C, D, and E] and ferritin in 84 term, singleton infants born to healthy Arab and South Asian women at Al-Ain hospital. Median serum ascorbic acid and 25-hydroxyvitamin D [25-OHD] concentrations were low in mothers and infants. In multivariate analysis, maternal serum 25-OHD correlated positively with birth weight while serum ferritin showed a negative correlation