Early response to vitamin D2 in children with calcium deficiency rickets.

Abstract

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.

• Authors: Tom D Thacher, Philip R Fischer, Christian O Isichei, John M Pettifor
• Journal: The Journal of pediatrics (J Pediatr) Vol. 149 Issue 6 Pg. 840-4 (Dec 2006) ISSN: 0022-3476 [Print] United States
• PMID: 17137904 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Ergocalciferols
• Vitamins
• Vitamin D
• 1,25-dihydroxyvitamin D
• Calcium

Topics

• Administration, Oral
• Calcium (deficiency)
• Child, Preschool
• Deficiency Diseases (drug therapy)
• Ergocalciferols (administration & dosage)
• Female
• Humans
• Infant
• Male
• Rickets (drug therapy)
• Time Factors
• Vitamin D (analogs & derivatives, blood)
• Vitamins (administration & dosage)