Low vitamin D status in children with sickle cell disease

OBJECTIVES: To examine vitamin D status in children with sickle cell disease (SCD)-SS and its relation to season and dietary intake. STUDY DESIGN: Growth, dietary intake, 25-hydroxyvitamin D (25-OHD), and parathyroid hormone levels were measured. Children with low and normal vitamin D status were compared. Low vitamin D status was defined as a serum concentration of 25-OHD <27.5 nmol/L. Serum 25-OHD and parathyroid hormone levels were compared among children with SCD-SS and healthy children. RESULTS: Children with SCD-SS (n=65), 5 to 18 years of age, were evaluated. Mean (+/-SD) serum 25-OHD concentration was 25.5 +/- 12.8 nmol/L; 65% of subjects had low vitamin D status. Low vitamin D prevalence was highest during spring (100%). Children with SCD-SS were at higher risk for low vitamin D status than healthy children. Vitamin D intake was lower in subjects with SCD-SS and low vitamin D than those with normal serum vitamin D status (P <.05). CONCLUSIONS: Low serum vitamin D status was highly prevalent in black children with SCD-SS. Vitamin D status was associated with season and dietary intake.     

Early response to vitamin D2 in children with calcium deficiency rickets

OBJECTIVE: To assess the effect of vitamin D(2) administration on serum vitamin D metabolite concentrations in calcium deficiency rickets. STUDY DESIGN: We administered vitamin D(2), 50,000 IU orally to 16 Nigerian children 15 to 48 months of age with radiographically active rickets. We measured calcium and vitamin D metabolites at baseline and at 1, 3, 7, and 14 days. RESULTS: At baseline, ranges of serum 25-hydroxyvitamin D (25(OH)D) concentrations were 18 to 40 nmol/L (7-16 ng/mL), and 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) concentrations were 290 to 790 pmol/L (120-330 pg/mL). After vitamin D administration, serum 25(OH)D and 1,25(OH)(2)D concentrations rapidly rose and peaked at 2.8 and 1.9 times the baseline values (P < .001), respectively, at 3 days. Positive correlations between 1,25(OH)(2)D and 25(OH)D were strongest at day 3 (r = 0.84, P < .001) and weakest at day 14 (r = 0.41, P = .11). The relationship of 1,25(OH)(2)D with 25(OH)D at baseline and the increase in 1,25(OH)(2)D in response to vitamin D were similar to those described in children with vitamin D deficiency. However, unlike the pattern in vitamin D deficiency, 1,25(OH)(2)D remained positively correlated with 25(OH)D after administration of vitamin D. CONCLUSION: Dietary calcium deficiency increases the demand for 25(OH)D above that required in vitamin D deficiency to optimize 1,25(OH)(2)D concentrations. Assessment of vitamin D sufficiency in persons or communities may need to be adjusted for habitual dietary calcium intake.     

血清25-羟维生素D在佝偻病诊断中的应用价值

目的：探讨血清25 羟维生素D［25（OH）D］在维生素D缺乏性佝偻病早期诊断中的意义。方法：检测对照组（73例）、可疑组（45例）和佝偻病组（65例）的血清25（OH）D、钙、磷、碱性磷酸酶浓度,并通过ROC曲线对血清25（OH）D的诊断价值进行评价。结果：对照组、可疑组和佝偻病组的血清25（OH）D水平分别为112±37、83±30和72±31 nmol/L,后两者均显著低于对照组（F=26.174,P0.05）。可疑组和佝偻病组的维生素D缺乏率均显著高于对照组（χ2=33.346, P0.05）。结论：血清25(OH)D水平在可疑及确诊佝偻病的患儿中显著降低,可以反映维生素D的营养状况,适用于佝偻病的早期筛查。     

新生儿维生素D营养状况调查

目的通过测定新生儿血清25-羟维生素D[25（OH）D]、甲状旁腺激素（PTH）、钙、磷浓度,了解兰州市新生儿维生素D营养状况,指导临床补充维生素D。方法选取2012年9～12月在兰州大学第一医院住院的90例新生儿为研究对象,早产儿30例,足月儿60例,采用酶联免疫法检测两组患儿生后10天内血清25（OH）D、PTH浓度,并分析两者之间的相关性;血清标本的钙、磷水平由贝克曼AU2700全自动生化分析仪测定。结果早产儿血清25（OH）D浓度为（21．9±2．5）nmol／L,显著低于足月儿（34．9±10．8）nmol／L,差异有统计学意义（P〈0．05）;早产儿血清町H浓度为（94．7±40．2）pg／ml,显著高于足月儿（56．1±30．0）pg／ml,差异有统计学意义（P〈0．05）,新生儿血清25（oH）D水平与明H呈负相关;旱产儿血钙浓度为（2．1±0．3）mmob／L,低于足月儿（2．3±0．3）mmol／L,差异有统计学意义（P〈0．05）;早产儿血磷浓度为（1．8±0．7）mmoL／L,足月儿为（1．6±0．5）mmol／L,差异无统计学意义（P〉0．05）。结论兰州市新生儿普遍存在维生素D缺乏或不足的现象,应加强孕母和新生儿的维生素D补充。     

High prevalence of moderately severe vitamin D deficiency in preterm infants

Background: The recommended dose of vitamin D supplementation of preterm infants is based on data from populations in which severe vitamin D deficiency is uncommon and may be inadequate for infants in high risk population. However, data on vitamin D status of preterm infants in high‐risk populations, such as Middle Eastern countries is scarce. Methods: This study investigates the vitamin D status of Arab mothers and their preterm infants. Maternal serum and cord blood 25(OH)D, calcium (Ca), phosphorus (P) and alkaline phosphate (ALP) were measured at delivery. Serum 25(OH)D was measured by HPLC while the other biochemical parameters were measured by standard autoanalyzer. Results: Thirty‐four preterm infants were studied. The mean gestational age was 31.4 weeks and birth weight was 1667 g. The median serum 25(OH)D of 17.0 nmol/L in 28 mothers and 14.5 nmol/L in 34 cord blood samples were low. The median maternal and cord blood Ca, P and ALP levels were within normal range. Fifteen (44%) of the infants had moderately severe vitamin D deficiency (serum 25 (OH)D levels <12.5 nmol/L). The median serum 25(OH)D levels of mothers who had reportedly taken prenatal vitamin D supplementation and those who had not were similar (17.3 vs 16.3) nmol/L. The mean serum 25(OH)D levels among preterm infants in this study were low when compared to levels in Caucasians preterm infants on which the current vitamin D recommendations are based. Conclusion: The high prevalence of moderately severe vitamin D deficiency in Arab preterm infants provides a justification to investigate vitamin D requirement of preterm infants in this and other high‐risk populations.     

25 Hydroxyvitamin D and vitamin E absorption in healthy children and children with chronic intrahepatic cholestasis

Patients with chronic cholestasis have reduced 25-hydroxyvitamin D (25 OHD) and vitamin E levels. We determined serum concentrations of 25 OHD, 1,25-dihydroxyvitamin D [1,25(OH)₂D] and vitamin E before and after oral administration of 10 g/kg body weight 25-hydroxyvitamin D₃ (25 OHD₃) and 100 IU/kg body weight vitamin E, respectively, in 4 patients with intrahepatic cholestasis and 6 healthy children. Vitamin E increased in all controls but in only one of the four patients. In contrast, oral 25 OHD₃ induced a normal rise in circulating 25 OHD and 1,25(OH)₂D. The low serum levels of 25 OHD in the patients before the oral bolus may have been due to inadequate parenteral vitamin D administration and/or to the simultaneous phenobarbital treatment. The latter possibility is supported by the increase of serum 25 OHD into the normal range after withdrawal of phenobarbital in one of the four patients.We conclude that vitamin E has to be supplemented parenterally or in water-soluble oral form. Further studies are necessary to clarify whether high-dose long-term oral 25 OHD₃ supplementation is sufficient to prevent vitamin D deficiency in patients with chronic cholestasis.Abbreviations 25 OHD 25-hydroxyvitamin D - 25 OHD₃ 25-hydroxyvitamin D₃ - 24,25(OH)₂D 24,25-dihydroxyvitamin D - DBP vitamin D binding protein This report was presented in part at the XIX European Symposium on Calcified Tissues in Stockholm, June 1986. This study was supported by the Deutsche Forschungsgemeinschaft Bu-199-9-1     

High prevalence of vitamin D deficiency in newborn infants of high-risk mothers

Objective

To determine the prevalence of vitamin D deficiency in newborn infants of mothers at risk of vitamin D deficiency because of dark skin or the wearing of concealing clothes (such as a veil) compared with a group presumed not to be at risk. A second aim was to correlate these newborn infants'' vitamin D concentrations with biochemical parameters of vitamin D metabolism and bone turnover at birth.

Design

A prospective study conducted between April 2004 and February 2006 including women delivering during this period and their newborn infants.

Setting

The outpatient clinic of the obstetrics department, Sint Franciscus Gasthuis, Rotterdam, the Netherlands.

Patients

Eighty seven newborn infants of healthy mothers with either dark skin and/or concealing clothing (risk group) or light skin (control group).

Results

We found a significant difference in the prevalence of vitamin D deficiency (25‐hydroxyvitamin D₃ <25 nmol/l) between newborn infants of mothers at risk and those of mothers in the control group (63.3% vs 15.8%; p<0.001). Mean alkaline phosphatase concentrations were significantly higher in the at risk group.

Conclusions

Newborn infants of mothers with dark skin or wearing concealing clothes are at great risk of vitamin D deficiency at birth. The clinical implications are unknown. Further research is necessary to determine the long‐term consequences of maternal and neonatal vitamin D deficiency so that guidelines on vitamin D supplementation during pregnancy can be issued.     

石家庄市夏季汉族4月龄至14岁健康儿童血清25-羟维生素D和甲状旁腺素的关系

目的探讨汉族儿童青少年夏季血清25-羟维生素D(25OHD)和甲状旁腺素(PTH)水平的关系,以及儿童青少年是否存在PTH进入平台期的血清25OHD拐点值。方法河北医科大学第二医院儿科生长发育门诊于2011年6~8月及2012年6~8月向社会招募4月龄至14岁健康儿童青少年。分为1岁、~3岁、~6岁、~10岁和~14岁组。分别采用酶联免疫法和化学发光免疫分析法测定血清25OHD和全段PTH水平。对血清25OHD与PTH水平的关系分别行直线、二次多项式、指数和对数拟合等,计算血清PTH水平进入平台期的血清25OHD阈值。结果共招募632名健康儿童青少年,男童372名,女童260名。1血清25OHD和PTH水平的中位数(P25,P75)分别为56.7(42.2,76.4)nmol·L-1和2.5(2.0,3.3)pmol·L-1。2血清25OHD与PTH在除~10岁组外的其余年龄组中均呈负相关。3二次多项式回归方程能较好反映血清25OHD和PTH之间的曲线关系。回归方程为PTH(pmol·L-1)=4.2698-0.0352·25OHD+0.0002·25OHD2,R2=0.0684。PTH进入平台期时血清25OHD的拐点值为88 nmol·L-1,对应的PTH值为2.72 pmol·L-1。结论 4月龄至14岁汉族儿童青少年的血清25OHD和PTH水平呈负相关,且理想的血清25OHD水平可能为88 nmol·L-1。     

Parathyroid function in different stages of vitamin D deficiency rickets

Direct measurements of parathyroid activity are available in only small numbers of children with vitamin D deficiency rickets (VDR). Therefore serum immunoreactive parathyroid hormone (iPTH) and the urinary cyclic adenosine-3,5-monophosphate excretion (UcAMP) were measured together with other important indices of calcium metabolism in 24 patients (aged 2–42 months) with VDR before vitamin D treatment. iPTH and UcAMP were significantly elevated in comparison to age-matched controls. In patients there was a highly significant positive correlation between iPTH and UcAMP and a negative relationship between both indices of parathyroid activity to serum phosphate and urine calcium, respectively, indicating that the simple measurement of serum phosphate and/or urine cAMP and Ca provides a reliable tool for the assessment of secondary hyperparathyroidism in VDR. In two patients classified as being in the early stage of VDR the parathyroid activity was not elevated despite hypocalcemia indicating relative hypoparathyroidism.Twelve patients with VDR were followed during vitamin D therapy: Within the first 2 weeks of treatment UcAMP slightly increased and thereafter decreased in most patients, but was still elevated in three patients even after 7 weeks, whereas iPTH became normal within 3 weeks of treatment. This favors the concept that vitamin D deficiency diminishes the activation of renal adenylate cyclase by PTH which is overcome by the highly increased PTH secretion in the advanced stages of rickets.The basal and calcium-stimulated serum calcitonin (CT) levels, determined in some of the patients, were normal, ruling out a significant disturbance of CT secretion in VDR.Dedicated to Prof. Dr. H. Bickel on the occasion of his 65th birthday     

Therapeutic and collateral effects of 25-hydroxycholecalciferol in vitamin D deficiency

The clinical and biochemical response to 25-hydroxycholecalciferol (25-HCC) and vitamin D₃, 150 g/day for 20 days has been compared in infants aged 3–18 months with nutritional rickets. The infants were allocated at random to Group I (11 infants) treated with 25-HCC and Group II (9 infants) treated with vitamin D₃. In addition 15 matched control children without rickets were allocated to Group III and received 25-HCC 75 g/day for 20 days. Preliminary studies showed that plasma calcium, phosphorus, alkaline phosphatase and urine pH all differed significantly between the rachitic and control groups. The biochemical parameters in both groups of rachitic children became normal after treatment with the exception of plasma alkaline phosphatase which remained elevated. The control group showed a significant increase in plasma and urine calcium values in spite of the low dose of 25-HCC. The findings suggest that 25-HCC is as effective as vitamin D₃ in the treatment of rickets but did not demonstrate any therapeutic advantage.     

Ultraviolet B radiation improves serum levels of vitamin D in patients with cystic fibrosis

Background: Ultraviolet B (UVB) radiation can be used in the prevention and treatment of vitamin D deficiency. Aim: To investigate, in a controlled study of patients with cystic fibrosis (CF), whether regular UVB radiation would improve serum levels of calcidiol during the dark season (October-April). Methods: Thirty patients with mild to moderate disease were included (aged 9-40 y). All patients had cholecalciferol supplementation. One group (15 patients) was given UVB one to three times a week for 6 mo and one group (15 sex- and age-matched patients) served as controls. The radiation source consisted of three TL 12/40W UVB fluorescent lamps. Initial treatment duration was 1 min, subsequently increased by 0.5-1 min/treatment to a maximum of 10 min. Results: The mean initial serum calcidiol levels were 21 ng/ml in the controls and 22 ng/ml in the intervention group. Serum calcidiol levels increased to 44 ng/ml after 8 wk and to 50 ng/ml after 24 wk of UVB radiation; the corresponding serum levels in the controls were 19 and 25 ng/ml, respectively. The mean serum calcitriol levels increased in the treated group and were unaltered in the control group.

Conclusions: UVB radiation was effective in increasing vitamin D levels in patients with CF. The study results imply that UVB radiation is valuable in chronic conditions associated with vitamin D deficiency.     

儿童特应性皮炎严重度与维生素D水平的相关性

目的探讨儿童特应性皮炎(AD)疾病严重程度与维生素D水平的相关性。方法纳入152例AD患儿,以AD严重程度评分(SCORAD)评估AD严重度,液相色谱-串联质谱法检测血清25-羟维生素D[25 (OH)D],分析AD严重程度与血清25(OH)D水平的相关性。结果 152例AD患儿中,男81例、女71例,中位年龄3.5岁。轻度、中度、重度AD患儿分别为51例(33.6%)、80例(52.6%)、19例(12.5%)。血清25(OH)D充足55例(36.2%),不足65例(42.8%),缺乏32例(21.1%)。AD患儿SCORAD评分与血清25(OH)D水平无显著相关性(r=-0.047,P=0.567),与血清总IgE呈显著正相关(r=0.244,P=0.003),与血嗜酸性粒细胞比例呈显著正相关(r=0.239,P=0.004)。结论 AD儿童中血清维生素D缺乏和不足者较多,但AD的严重程度与血清25(OH)D水平无显著相关性。     

晚期早产儿脐血维生素D水平及维生素D3补充对婴幼儿行为发育的前瞻性随机对照研究（英文翻译）

目的 探讨晚期早产儿25-羟维生素D［25-hydroxyvitamin D,25(OH)D］水平及维生素D₃补充对婴幼儿神经行为发育的影响。 方法 前瞻性选取2017年6月—2020年6月收治的晚期早产儿161例为研究对象,根据脐血25(OH)D水平分为充足组（52例）、不足组（53例）、缺乏组（56例）,每组按随机数字法分为A亚组（维生素D₃ 800 IU/d）、B亚组（个体化补充维生素D₃）。分析比较各组生后3个月25(OH)D水平、纠正胎龄10个月及纠正胎龄18个月25(OH)D水平及Gesell发育量表评分的差异。 结果 生后24 h内及3个月时,不足组、缺乏组25(OH)D水平低于充足组（P<0.05）,不足组25(OH)D水平高于缺乏组（P<0.05）;缺乏组生后3个月时B亚组25(OH)D水平高于A亚组（P<0.05）。不足组和缺乏组纠正胎龄10个月、纠正胎龄18个月时Gesell发育量表5个能区得分均低于充足组（P<0.05）;缺乏组纠正胎龄10个月时言语能、纠正胎龄18个月时粗大动作能得分低于不足组（P<0.05）。缺乏组B亚组纠正胎龄10个月时适应能、纠正胎龄18个月时适应能和应物能得分高于A亚组（P<0.05）。 结论 晚期早产儿脐血25(OH)D水平存在明显差异,个体化补充维生素D方案对于纠正维生素D缺乏更为有效。出生时及婴儿早期维生素D水平对神经行为发育有一定影响。     

早产儿维生素D两种补充方案的疗效对比：前瞻性随机对照研究

目的 探讨不同维生素D补充方案对出生胎龄 < 34周早产儿生后第28天维生素D营养状况的影响。方法 将59例2018年10月至2019年10月出生胎龄 < 34周的住院早产儿随机分为肌注组（n=30）和口服组（n=29）。肌注组单次肌内注射维生素D₃注射液（10 000 IU/kg）,口服组口服维生素D₃滴剂（900 IU/d）,持续25 d。采集两组患儿生后48 h内（维生素D₃补充前）及第28天静脉血,检测血清25-羟维生素D[25(OH) D]水平。结果 生后48 h内,59例早产儿维生素D缺乏（≤15 ng/mL）率为78%;两组血清25(OH) D水平及维生素D缺乏率比较差异无统计学意义（P > 0.05）。生后第28天,肌注组血清25(OH) D水平显著高于口服组（P < 0.05）,肌注组维生素D缺乏率显著低于口服组（P < 0.05）,且无维生素D过量或中毒病例。结论 单次肌内注射10 000 IU/kg维生素D₃可显著提升出生胎龄 < 34周早产儿生后第28天血清25(OH) D水平,且能安全并有效地降低维生素D缺乏率。