Bone turnover in children with vitamin D deficiency rickets before and during treatment

Biochemical markers of bone formation [alkaline phosphatase, osteocalcin, and carboxyterminal propeptide of type I procollagen (PICP)] and bone resorption [cross-linked carboxyterminal telopeptide of type I collagen (ICTP) and cross-linked N-telopeptides of type I collagen (NTX)] were measured in 14 children aged 8.5-10.5 mo with vitamin D deficiency rickets before and longitudinally during vitamin D treatment (3000-4000 IU/daily). Forty-four healthy children aged 8-10.5 mo were enrolled as sex- and age-matched controls. Before treatment, serum levels of alkaline phosphatase, PICP, and ICTP, and urinary excretion values of NTX were significantly higher, and serum osteocalcin levels significantly lower than controls (31.4 +/- 3.5 microkat/L and 9.8 +/- 2.9 microkat/L, p < 0.001; 1025 +/- 89 microg/L and 952 +/- 97.4 microg/L, p < 0.02; 15.6 +/- 2.6 microg/L and 14.2 +/- 1.3 microg/L, p < 0.01; 370.7 +/- 109.4 nmol BCE and 201.8 +/- 69.2 nmol BCE, p < 0.001: 17.6 +/- 9.1 microg/L and 22.5 +/- 7.6 microg/L, p < 0.05, respectively). During treatment, serum alkaline phosphatase levels progressively declined in association with the radiographic healing of the skeletal lesions. Serum levels of osteocalcin, PICP, and ICTP, and urinary excretion values of NTX showed a transient but significant (p < 0.05 to p < 0.001) increase in comparison with baseline values during the first 2-4 wk of treatment, and decreased slowly thereafter. They were within the mean +/- 2 SD of controls before the recovery of the skeletal lesions. CONCLUSIONS: These findings suggest that children with vitamin D deficiency rickets have increased bone turnover before and during the first weeks of treatment. Alkaline phosphatase is a more reliable marker than osteocalcin, PICP, ICTP and NTX for diagnosing and monitoring these patients.     

Serum beta-carotene, retinol, and alpha-tocopherol levels during mineral oil therapy for constipation

Twenty-five children with chronic constipation underwent serial monitoring of serum beta-carotene, retinol (vitamin A1), and alpha-tocopherol (vitamin E) levels during mineral oil therapy. Mineral oil was administered between meals. Patients were monitored for up to four months of therapy. Mean serum beta-carotene levels fell from 1.0 +/- 0.5 mumol/L (55.7 +/- 26.0 micrograms/dL) to 0.7 +/- 0.4 mumol/L (35.9 +/- 22.1 micrograms/dL) after the first month of mineral oil therapy and remained depressed throughout the remainder of the study. Serum alpha-tocopherol levels remained unchanged throughout the observation period. There was a modest increase in serum retinol levels during the study, especially after three months (from 1.48 +/- 0.84 mumol/L [42.3 +/- 24.1 micrograms/dL] to 2.22 +/- 0.77 mumol/L [63.5 +/- 22.1 micrograms/dL]). We conclude that while a short course of mineral oil can induce a reduction in the serum level of beta-carotene, the treatment has no adverse effect on serum levels of retinol and alpha-tocopherol.     

The relationship between osteocalcin levels and sexual stages of puberty in male children

Osteocalcin is a specific and reliable marker which increases with rapid bone turnover and gives data about bone metabolism. The pubertal growth spurt is also known as a good example of rapid bone turnover. The aim of this study was to determine whether osteocalcin is a useful marker for the pubertal growth spurt period. In this study, osteocalcin levels in male adolescents were examined in relation to their sexual maturation stage and age. The osteocalcin levels and alkaline phosphatase levels were compared during the pubertal growth spurt. Serum osteocalcin and alkaline phosphatase levels were evaluated in 100 eligible healthy male children and adolescents (aged 10 to 17 years). Five groups (n: 20 each) of children and adolescents were formed according to their sexual maturation stages. Finally, the subjects were divided into three main groups in relation to the pubertal growth spurt and sexual maturation stages. Data were evaluated and compared among these three groups: First group = Stage 1 (prepuberty) + Stage 2 (early puberty) consisted of 40 (20 + 20) children and adolescents. Their mean osteocalcin value was 17.2 +/- 6.3 ng/ml and alkaline phosphatase 573.8 +/- 143.9 IU/L. Second group: Stage 3 + Stage 4 consisted of 40 (20 + 20) children and adolescents. These groups were known as the pubertal growth spurt groups. Their mean osteocalcin value was 29.4 +/- 10.6 ng/ml and alkaline phosphatase 728.4 +/- 233.9 IU/L. Third group: In this group, there were 20 children and adolescents who reached Stage 5 of sexual maturation and whose pubertal growth spurt was slowing. Their mean osteocalcin value was 15.3 +/- 5.8 ng/ml and alkaline phosphatase 435.8 +/- 184.8 IU/L. During the pubertal growth spurt, there is a relationship between bone remodelling and increasing osteocalcin and alkaline phosphatase levels. When sexual maturation reaches Stage 4 at 14 years old, osteocalcin and alkaline phosphatase levels make a peak, associated with the rapid growth in height. As sexual maturation reaches Stage 5, osteocalcin and alkaline phosphatase levels gradually decrease with growth maturation and their levels decline to the level of adults at the completion of this period. Our study showed that osteocalcin and alkaline phosphatase levels can be used as markers for evaluation of the growth spurt period.     

反复呼吸道感染患儿IgG亚类及维生素A水平的关联研究

目的：反复呼吸道感染（RRTI）是儿科的常见病之一。目前研究发现其发病与维生素A缺乏,免疫功能异常有关。该研究检测了RRTI患儿IgG 亚类及维生素A水平,并对该类病人维生素A缺乏与IgG亚类缺陷之间的关系进行了初步的探讨。方法：采用ELISA方法检测血清IgG 亚类;采用高效液相色谱分析Miller改良法进行维生素A的测定。结果：RRTI患者血清IgG2,4水平及维生素A水平均低于健康对照组,差异具有显著性（P<0.05）。结论：RRTI患者虽IgG正常,但是可能存在IgG亚类异常。RRTI患者存在维生素A水平低于正常儿童,而且IgG2,4水平的降低可能与维生素A水平有关。［中国当代儿科杂志,2007,9（6）：557-558］     

Maternal vitamin D deficiency and vitamin D supplementation in healthy infants

The objective of this study was to evaluate the common effects of maternal vitamin D deficiency, various doses of vitamin D given to newborns and the effects of these on vitamin D status in early childhood. Seventy-eight pregnant women and 65 infants who were followed up in various health centers were included in the sudy. 25-hydroxyvitamin-D (25-OHvitD), calcium (Ca), phosphorus (P) and alkaline phosphatase levels were measured in blood samples drawn from pregnant women in the last trimester. Infants born to these mothers were given 400 or 800 IU of vitamin D subsequently at the start of the second week. 25-OHvitD, Ca, P and alkaline phosphatase levels of the 65 infants who were brought in for controls (May-September 2000) were measured and hand-wrist X-rays were evaluated. We analyzed the relationship between vitamin D status of the mothers and infants and socio-economic status; mothers' dressing habits (covered vs uncovered), educational level, and number of pregnancies; and sunlight exposure of the house. Covered as a dressing habit meant covering the hair and sometimes part of the face and wearing dresses that completely cover the arms and legs. In 40 infants who were breast-fed and received the recommended doses of vitamin D on a regular basis, the relationship between serum vitamin D levels and supplementation doses given was analyzed. Serum 25-OHvitD level of the mothers was 17.50 +/- 10.30 and 94.8% of the mothers had a 25-OHvitD level below 40 nmol/L (below 25 nmol/L in 79.5%). The risk factors associated with low maternal 25-OHvitD were low educational level (p = 0.042), insufficient intake of vitamin D within diet (p = 0.020) and "covered" dressing habits (p = 0.012). 25-OHvitD level of the infants was 83.70 +/- 53.70 nmol/L, and 24.6% of the infants had 25-OHvitD levels lower than 40 nmol/L. Risk factors for low 25-OHvitD levels in infants were a) not receiving recommended doses of vitamin D regularly (p = 0.002) and b) insufficient sunlight exposure of the house (p = 0.033). There was a pour but significant correlation between maternal vitamin D levels and infants' 25-OHvitD levels at four months (r = 0.365, p < 0.05). No significant correlation was found between 25-OHvitD levels and supplementation doses of vitamin D (19 infants were supplemented with 400 IU/day and 21 with 800 IU/day of vitamin D) (p = 0.873). Severe maternal vitamin D deficiency remains a commonly seen problem in Turkey. However, vitamin D deficiency can be prevented by supplementation of vitamin D to newborns (at least 400 IU). Supplementation of 800 IU vitamin D in the areas of maternal vitamin D deficiency has no greater benefits for the infants.     

Long-term influence of calcitriol (1,25-dihydroxyvitamin D) and supplemental phosphate in X-linked hypophosphatemic rickets

Ten patients with hypophosphatemic rickets (eight with X-linked familial form) were treated with vitamin D2 (10,000 to 75,000 units per day) and oral phosphate (1.5 to 3.6 gm) for a total of 438 treatment months. Therapy was then changed to calcitriol (17 to 34 ng/kg/day) and the same phosphate dose. Patients served as their own controls, and significant biochemical changes noted were an increase in immunoreactive parathyroid hormone from 29 +/- 9 (SD) microliters Eq/ml (pre-phosphate) to 62 +/- 34 on vitamin D2 plus PO4, then decreasing to 40 +/- 20 on a regimen of 1,25-dihydroxyvitamin D (1,25(OH)2D) plus PO4; serum PO4 rose from 2.44 +/- 0.45 (SD) mg/100 ml to 3.06 +/- 0.79 and then to 3.43 +/- 0.76; alkaline phosphatase activity decreased from 677 +/- 298 (SD) IU/liter to 457 +/- 183 to 290 +/- 176. Serum calcium and creatinine levels were unchanged. Both urinary calcium excretion and calcium-creatinine ratio decreased after therapy with 1,25(OH)2D. Urinary phosphate excretion was higher after calcitriol administration. Serum 1,25(OH)2D levels were low in these vitamin D2-treated patients, and an inverse relationship between serum 25(OH)D and 1,25(OH)2D was found. Improved bone mineralization was evident from serial assessment by photon absorptiometry, and radial bone mineral content rose from 75.3% +/- 2.2% of expected to 82.2% +/- 1.4% (P less than .005). Stature was improved when assessed by standard deviation for chronologic age but did not reach statistical significance. Long-term 1,25(OH)2D plus phosphate therapy appears to be more efficacious than vitamin D2 in this form of rickets, particularly in improving phosphate homeostasis.     

Alendronate treatment in children with osteogenesis imperfecta

BACKGROUND: Recent studies reported beneficial effect of cyclical intravenous administration of pamidronate in children and adolescents with osteogenesis imperfecta (OI). However, this treatment requires frequent hospital admissions and is relatively expensive. Alendronate is an oral bisphosphonate effectively used in adults with osteoporosis. Experience with alendronate treatment in children with OI is limited. AIMS: To report our experience with alendronate in children with OI. METHODS: 12 children with OI (7 with type I, 4 with type III and 1 with type IV; 7 boys, 5 girls) aged 1.8 to 15.4 years (7.9+/-; 4.4 yrs) were included in this retrospective study. The patients were treated with alendronate in a dose of 5-10 mg/day along with calcium (500 mg/day) and vitamin D (400-1000 IU/day) supplements for 19.8+/-11.3 months (range: 7-46 months). Serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), osteocalcin (OC), pyrilinks-D and urinary Ca/Cr ratio were studied 3 monthly and bone mineral density (BMD) by DXA on 6-12 monthly basis. RESULTS: Fracture rate of the patients significantly decreased after treatment (1.2+/-1.5 vs. 0.16+/-0.32 per year, P<0.05). Treatment improved bone density in each individual case. Z-scores of lumbar DXA (L2-L4) significantly increased during treatment (-4.60+/-1.30 vs - 2.47+/-1.52, P< 0.05). Urinary pyrilinks-D decreased with treatment (90.8+/-136.3 vs. 35.1+/-29.9, P< 0.05). Serum Ca, P, ALP, OC and urinary Ca/Cr did not change significantly during treatment. CONCLUSION: We conclude that alendronate is effective, safe and practical alternative to intravenous bisphosphonates in treatment of children with OI.     

Malabsorption of liposoluble vitamins in a child with bile acid deficiency

A male born to first cousins presented at 12 months with hypocalcemic convulsions, rickets, epistaxis due to vitamin K deficiency, and extremely low serum levels of beta-carotene and vitamin A. Liver function was altered moderately (glutamic-oxaloacetic transaminase, 55 U/L; glutamic-pyruvic transaminase, 37 U/L; lactate dehydrogenase, 255 U/L; alkaline phosphatase, 437 U/L). To correct the deficiencies, 8,000 IU vitamin D/day, 10,000 IU vitamin A/day, and intramuscular administration of vitamin K1 were required. At 9 years, he presented signs of neuromuscular affection, and the serum vitamin E level (measured for the first time) was extremely low. Classic lipid malabsorption syndromes (abetalipoproteinemia, chronic cholestasis, mucoviscidosis, coeliac disease, Whipple's disease) were excluded by appropriate examinations. Composition of duodenal bile acids was characterized by undetectable levels of cholic acid metabolites, and only chenodeoxycholic acid metabolites were present. Serum total bile acid concentration was normal, with an atypical low cholic acid/chenodeoxycholic acid ratio and abnormal presence of 3 beta-OH-delta 5-cholenic acid and 6-OH-bile acids. Urinary bile acid composition was also characterized by elevated 6-OH-bile acids. Known enzymopathies of the bile acid synthetic pathway were excluded (cerebrotendinous xanthomatosis, cerebro-hepato-renal syndrome of Zellweger, coprostanic acidemia). Bile acid pool sizes were determined by using stable isotopes: cholic acid pool size [2.90 (N, 32 +/- 16) microM/kg] and chenodeoxycholic acid pool size [10.8 (N, 32.6 +/- 9.9) microM/kg] were extremely low; fractional turnover rates of both bile acids were in a normal range.(ABSTRACT TRUNCATED AT 250 WORDS)     

哮喘患儿血清IL 12 TGFβ1 与IgE 水平变化的研究

目的：检测哮喘患儿不同病期的白细胞介素12 ( IL-12) 、转化生长因子β1 ( TGFβ1 ) 与免疫球蛋白E( IgE) 水平变化的规律,并探讨不同病期IL-12,TGFβ1水平与IgE水平的相关性,据此阐述它们在哮喘中的临床意义。方法：采用ELISA 方法检测85例哮喘患儿及30例正常儿童的血清IL-12,TGFβ1与总IgE 水平。结果：哮喘组血清IL-12,TGFβ1水平明显低于对照组,而IgE 水平则哮喘组明显高于对照组,且发作期IL-12,TGFβ1 水平（28.42±10.73 ng/L,40.25±11.73 pg/mL）明显低于缓解期（40.42±15.26 ng/L,65.41±22.38 pg/mL）,差异有显著性 (P< 0. 01),缓解期血清IL-12,TGFβ1 水平明显低于对照组（67.42±20.58 ng/L,178.54±90.56 pg/mL）,差异有显著性(P<0.01),发作期血清IgE 水平（280.35±80.54 IU/mL）明显高于缓解期（145.67±51.25 IU/mL）, 差异有显著性(P< 0.01), 缓解期血清IgE 水平明显高于对照组（53.61±13.32 IU/mL）, 差异有显著性(P<0.01),哮喘患儿血清IL-12,TGFβ1水平与IgE呈负相关(P< 0.01)。结论：哮喘患儿存在IL-12,TGFβ1及IgE 水平失衡,提示IL-12,TGFβ1 在哮喘的发病中起着重要作用,检测它们的水平可为哮喘的诊断及判断病情提供依据。     

Unique form of rickets with low serum 25-hydroxyvitamin D in two normally nourished children

We present an unusual type of rickets involving two children: a 2 year old boy and a 15 month old boy, who presented with marked bowing of the lower extremities and bulging of costochondral junctions. Both children had normal growth, with their height and body weight greater than the 50th and 97th percentile for age. Roentgenograms of their extremities showed the typical changes of vitamin D refractory rickets. Serum alkaline phosphatase levels were elevated and serum levels of calcium and phosphate were both within the normal range. No primary cause for the rickets, including nutritional deficiencies, was found in the two patients. Characteristic findings were persistently low serum 25-hydroxyvitamin D (25-OH-D) and normal 1,25-dihydroxyvitamin D (1,25-(OH)2-D). Improvements in clinical and X-ray findings were observed after either oral administration of 1 α-(OH)-D3 (9–15 μg per day) or massive vitamin D2 therapy (600 000 IU single injection). The low serum levels of 25-OH-D did not increase unless massive vitamin D2 therapy was also given. These two cases represent a unique form of rickets that does not meet the criteria for any type of previously known rickets.     

d-Alpha-tocopheryl polyethylene glycol-1000 succinate enhances the absorption of vitamin D in chronic cholestatic liver disease of infancy and childhood.

Rickets and osteopenia, common problems in chronic childhood cholestasis, have been attributed to vitamin D malabsorption leading to reduced serum levels of 25(OH)-vitamin D. d-alpha-Tocopheryl polyethylene glycol-1000 succinate (TPGS), a water-soluble form of vitamin E, forms micelles at low concentration. We evaluated the potential role of TPGS in enhancing vitamin D absorption in eight children (aged 5 mo to 19 y) with severe chronic cholestasis (three extrahepatic biliary atresia, three nonsyndromic intrahepatic cholestasis, and two Alagille syndrome). To evaluate vitamin D absorption, the subjects received vitamin D3 1000 IU/kg (maximum dose of 50,000 IU); they then received the same dose of vitamin D3 mixed with TPGS (25 IU/kg). Serial serum vitamin D3 levels and areas under the curve were measured. All patients had enhanced absorption of vitamin D when it was administered in a mixture with TPGS. Mean area under the curve for serum vitamin D3 was 403.0 +/- 83.1 nmol x h/L (155.6 +/- 32.1 ng x h/mL), with a mean rise above baseline of 13.5 +/- 1.8 nmol/L (5.2 +/- 0.7 ng/mL) with vitamin D/TPGS compared with no rise when vitamin D was given alone (both p less than 0.001). Seven patients have been followed for at least 3 mo while receiving the vitamin D/TPGS combination. Those with initially low serum 25(OH)-vitamin D levels (less than 37.5 nmol/L or 15 ng/mL) had normalization (range 37.5-146 nmol/L) within 1 mo, whereas those with initially normal levels remained normal. While the patients were receiving vitamin D/TPGS, serum vitamin E to total lipid ratio either normalized or remained normal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Asymptomatic rickets in adolescent girls

Objective Inadequate sunlight exposure and calcium intake during rapid growth at puberty lead to hypocalcemia, hypovitaminosis D and eventually to overt rickets. To determine serum biochemical findings of rickets in healthy 11–15 yr old girls, the effect of sunlight exposure and oral vitamin D supplementation on serum 25-hydroxy vitamin D and calcium administration in girls with abnormal findings during December 2002 through March 2003 in Tehran, Iran. Methods Healthy middle school girls were selected for estimation of vitamin D, calcium and phosphorus intake by a three-day food recall. And measurement of serum calcium, phosphorus, parathyroid hormone, alkaline-phosphatase and 25-hydroxyvitamin D concentration. The girls with abnormal findings divided in two groups. Hypovitaminosis D girls subdivided into two groups, supplementary sunlight exposure and vitamin-D administrated for them and calcium administration for the second group for 20 days. Results Of 414 girls, the mean daily vitamin D acquirment and calcium intake were 119 ± 52 IU and 360 ± 350 mg among all girls respectively. Mean serum 25-hydroxyvitamin D with two or more abnormal biochemical findings in 15 (3.6%) girls (group I) were 7.8 ng/ml and alkaline phosphatse with normal or low calcium in 29 (7%) girls (group II) was 1187 IU/L. Mean serum calcium was 8.2 mg % in 8 of 29 girls. Serum 25-hydroxyvitamin D before and after sunlight exposure was 7.1 ± 1.9 ng/ml and 13.9 ± 2.4 ng/ml and vitamin D administration was 7.4 ± 1.8 ng/ml (group la) and 27.9 ± 4.2ng/ml (group lb) respectively. Serum alkaline phosphatase before and after calcium administration were 1187 IU/L and 666 IU/L respectively. Conclusion We conclude that low daily calcium intake, and vitamin D acquirement are two important problems in Iranian girls during rapid growth at puberty; therefore, for prevention of overt rickets calcium and vitamin D Supplementation appear to be necessary.     

Plasma zinc and growth status in preadolescent children with cystic fibrosis

OBJECTIVE: To investigate plasma zinc status in relation to dietary and supplemental zinc intake, growth and pulmonary status in preadolescent children with cystic fibrosis (CF) and pancreatic insufficiency (PI). METHODS: Fasting plasma zinc was assessed in children (age, 8-11 years) with CF and PI. Food (7-day weighed records) and supplemental zinc intake, serum alkaline phosphatase and albumin, pulmonary function (spirometry), coefficient of fat absorption (%COA, 72-hour fecal fat) and growth status [height adjusted for genetic potential (AHAZ), weight (WAZ) and BMI Z scores (BMIZ)] were assessed. RESULTS: For the 62 children (32 males), mean plasma zinc (+/-SD) was 16.8 +/- 3.1 micromol/L (110 +/- 20 ug/dL). Sixty-five percent of the subjects had levels above the study reference range of 9.2 to 15.3 micromol/L (60-100 ug/dL); no subjects had low zinc levels. Median (range) total daily zinc intake was 279% (83-988%) recommended dietary allowance, growth status was suboptimal (mean +/- SD: AHAZ, -0.8 +/- 1.0; WAZ, -0.5 +/- 1.2; BMIZ, -0.2 +/- 1.1), and forced expiratory volume at 1 second (FEV1) was 92 +/- 13% predicted. Plasma zinc was not correlated with growth, pulmonary or alkaline phosphatase status. Plasma zinc was correlated with serum albumin (r = 0.25, P < 0.05) and was inversely correlated with coefficient of fat absorption (as %; r = -0.30, P = 0.02). CONCLUSIONS: Under current patterns of care in CF Centers, total zinc intake and plasma zinc status were adequate. These findings suggest that zinc was not a limiting micronutrient for preadolescent children with CF and PI and mild-to-moderate lung disease, and not likely contributing to their suboptimal growth status.     

Vitamin A supplementation in acute diarrhea

BACKGROUND: Vitamin A supplementation reduces the severity of subsequent diarrheal episodes. This study was conducted to examine the effect of single oral high-dose vitamin A supplementation on the duration of acute diarrhea in 6- to 12-month-old infants who are not malnourished. METHOD: In this double-blind, randomized, placebo-controlled study, infants who were admitted to Hacettepe University Ihsan Dogramaci Children's Hospital Diarrheal Diseases Training and Treatment Unit with acute diarrhea were randomly assigned either to a group receiving a single oral dose of 100,000 IU vitamin A or placebo. There were 60 infants in each group. All infants were followed up until the diarrheal episode ended. Serum vitamin A levels were determined both at admission and 2 weeks later. RESULTS: No effect of vitamin A supplementation could be demonstrated on either the total duration of diarrhea (7.4 +/- 3.2 days in the treatment group vs. 7.8 +/- 3.1 days in the placebo group) or on its duration after intervention (3.8 +/- 2.3 days in the treatment group vs. 3.9 +/- 1.9 days in the placebo group; P > 0.05 for both comparisons). Serum vitamin A levels were not significantly different at admission (23.5 +/- 9.7 microg/dL in the treatment group vs. 24.1 +/- 9.7 microg/dL in the placebo group; P > 0.05) nor at the end of a follow-up period of 2 weeks (treatment: 33.3 +/- 13.7 microg/dL, placebo: 35.2 +/- 11.2 microg/dL; P > 0.05). However, the increase in serum vitamin A levels at the end of the 2-week follow-up interval for infants in both the treatment and placebo groups were found to be significant compared with levels at admission (P < 0.01). The mean weight gain in both groups were similar by the end of the first month (6.9 +/- 5.0% in the treatment group vs. 6.3 +/- 4.2% in the placebo group; P > 0.05). CONCLUSION: No effect of oral vitamin A supplementation on serum vitamin A levels, duration of diarrhea, or weight gain during an acute diarrheal episode could be demonstrated in our study group of infants between 6 and 12 months of age who had no malnutrition.     

Vitamin D insufficiency in preadolescent African-American children

To determine the proportion of vitamin D insufficiency in 6- to 10-year-old preadolescent African-American children residing in Pittsburgh, Pennsylvania and to estimate their therapeutic response to vitamin D 400 IU/day for 1-month, an open-label pre- and post-comparison of vitamin D status following vitamin D 400 IU daily for 1 month during winter and early spring was conducted. Outcomes included serum calcium, phosphorus, albumin, 25 hydroxyvitamin D [25 (OH) D], 1, 25 dihydroxyvitamin D [1, 25 (OH) (2) D], parathyroid hormone (PTH), and markers of bone turnover (serum bone-specific alkaline phosphatase, osteocalcin, and urine n-telopeptide crosslinked collagen type 1 [NTX]). Dietary intake of vitamin D was assessed using a food frequency questionnaire. Forty-one of the 42 enrolled subjects (mean age: 8.9 +/- 1.2 yrs [SD]) were analyzed, and 20/41 (49%) were vitamin D insufficient. Vitamin D insufficient group had a suggestive trend of being older (9.2 +/- 1.0 years vs. 8.5 +/- 1.3 years, p = 0.06) and more pubertally advanced (Tanner II: 7/20 vs. Tanner II: 1/21, p = 0.02). Mean dietary intake of vitamin D was 277 ( 146 IU/day (n = 41). Adequate intake for vitamin D (200 IU/day) was not met in 16/41 (39%); however, the dietary intake of vitamin D was not significantly different between the vitamin D insufficient and vitamin D sufficient groups.     

25-Hydroxyvitamin D levels during breast-feeding with or without maternal or infantile supplementation of vitamin D

Serum 25-hydroxyvitamin D (25-OHD), calcium, phosphorus, magnesium, and alkaline phosphatase levels of breast-fed infants and their mothers were studied by following 100 healthy term mother-infant pairs with different supplementation protocols of vitamin D. A pilot study in winter revealed that six of eight breast-fed infants without vitamin D supplementation had serum 25-OHD levels below the risk limit for rickets (5 ng/ml) at the age of 8 weeks. In the main study in winter groups, it was found that the 25-OHD levels were low (5.6 +/- 3.7 ng/ml) at the age of 8 weeks in the unsupplemented breast-fed infants, whose mothers were given vitamin D supplementation of 1,000 IU/day during lactation (group I), compared with the levels of those infants receiving either 400 (18.0 +/- 8.4 ng/ml, group II) or 1,000 IU (22.8 +/- 11.2 ng/ml, group III) vitamin D (group I vs. group II or III, p less than 0.001; group II vs. group III, NS). In group I 10 of 18 infants had serum 25-OHD levels less than 5 ng/ml compared with none of the infants in groups II and III. Yet the infants with 25-OHD levels less than 5 ng/ml showed no signs of clinical or biochemical rickets at the age of 8 or 20 weeks. In summer at delivery the maternal 25-OHD levels were good, but decreased thereafter. Also in summer groups, the infantile 25-OHD concentrations decreased; however, because the levels at delivery were high, they stayed in the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of different doses of vitamin D on osteocalcin and deoxypyridinoline in preterm infants

Background: Metabolic bone disease of prematurity is a common problem in preterm infants. The aim of the present paper was to measure the effect of vitamin D, in order to see the relation between vitamin D and urinary excretion of deoxypyridinoline (DPD), serum osteocalcin (OC), calcium (Ca), inorganic phosphorus (P), and alkaline phosphatase (ALP). Methods: Three different doses of vitamin D, 200 IU/kg (group 1, 11 infants), 400 IU/kg (group 2, 15 infants) and 800 IU/kg bodyweight/day (group 3, 11 infants), were administered to a total of 37 preterm infants between 15th day of birth until the 30th day of birth. Results: There were no significant differences in levels of serum Ca and P before and after vitamin D supplementation in all groups. Serum ALP levels were increased in all but significantly only in groups 1 and 3. Serum OC levels were also increased in each group by the treatment. Urinary DPD excretion was increased gradually by the increase in vitamin D intake, but it was significant only in group 3. Conclusion: High dose of vitamin D supplementation might accelerate bone turnover and increased urinary DPD levels might reflect increased bone resorption. To the best of the authors’ knowledge this is the first study comparing the effects of different vitamin D dose, by the means of urinary collagen cross‐links, on bone turnover in preterm infants.     

Vitamin E status in children with cystic fibrosis and pancreatic insufficiency

Vitamin E status was compared in 69 children (7.0-10.0 years) with cystic fibrosis and pancreatic with the National Health and Nutrition Examination Survey III sample (6.0-11.9 years). With median vitamin E intakes of 6 mg/day (dietary) and 224 mg/day (supplemental), children with cystic fibrosis had higher serum alpha-tocopherol:cholesterol ratios, higher alpha-tocopherol, and lower cholesterol levels than in the National Health and Nutrition Examination Survey.     

Renal osteodystrophy in children undergoing continuous ambulatory peritoneal dialysis

This paper describes a retrospective evaluation of the course of renal bone disease in 14 children undergoing treatment with continuous ambulatory peritoneal dialysis (CAPD) for an average of 11.9 +/- 1.5 months (mean +/- SE). The patients were divided in two groups according to the changes in serum alkaline phosphatase activity during the period of observation: five patients had alkaline phosphatase activity that decreased or was relatively stable (group I), and nine patients exhibited a rising serum alkaline phosphatase activity (group II). Serial radiological examinations showed adequate control of renal osteodystrophy in the patients of group I, whereas the patients of group II had no improvement or worsening of their bone disease. Group I had higher serum calcium and lower parathyroid hormone levels than group II at the end of period of observation despite similar dosage of vitamin D metabolite. The progression of bone disease was not related to the duration of CAPD or type of previous treatment for end stage renal disease. The observation that the radiological manifestations of secondary hyperparathyroidism were prevented in patients whose serum calcium levels were frequently above 2.62 mmol/liter (group I) while serum calcium levels between 2.25 and 2.50 mmol/liter in group II patients failed to lead to regression of secondary hyperparathyroidism is consistent with the existence of altered "set-point" regulation of the parathyroid gland in children undergoing CAPD.     

Hypovitaminosis D and vitamin D deficiency in exclusively breast-feeding infants and their mothers in summer: a justification for vitamin D supplementation of breast-feeding infants

OBJECTIVE: To determine the prevalence of hypovitaminosis D in exclusively breast-feeding infants and their mothers in a community where maternal sunshine exposure is low. STUDY DESIGN: Serum levels of calcium, phosphate, alkaline phosphatase, 25-hydroxy vitamin D (25-OHD), and intact parathyroid hormone were measured in 90 unsupplemented healthy term breast-feeding Arab/South Asian infants and their mothers in summer. Maternal dietary vitamin D intake was also estimated. RESULTS: The median age of infants was 6 weeks. The median serum 25-OHD concentrations in mothers (8.6 ng/mL) and infants (4.6 ng/mL) were low, and 61% of the mothers and 82% of the 78 infants tested had hypovitaminosis D (serum 25-OHD <10 ng/mL). The infants with hypovitaminosis D had elevated serum alkaline phosphatase and a tendency to higher serum intact parathyroid hormone levels. The average daily maternal vitamin D intake from commercial milk was 88 IU. CONCLUSIONS: Hypovitaminosis D is common in summer in exclusively breast-feeding infants and their mothers. The results provide justification for vitamin D supplementation of breast-feeding infants and mothers in the United Arab Emirates. Low vitamin D intake probably contributed to low maternal vitamin D status.