Vitamin D prophylaxis in children with a single dose of 150000 IU of vitamin D.
OBJECTIVE
To determine the efficacy of a single oral dose of 150,000 IU of vitamin D2 at the beginning of autumn for preventing winter vitamin D deficiency in children in Ushuaia (55 degrees S).


METHODS
The study was prospective.


METHODS
79 children clinically healthy with 8.6 +/- 1.4 y of age (X +/- s.d.).


METHODS
Fasting serum venous samples and 2 h urine samples were obtained immediately before and 6 w and 5 mon after the vitamin D dose. Parents informed consent was obtained previous to the study. In a subgroup of 30 children serum levels of calcium (sCa), phosphorus (sP), total alkaline phosphatase (TAP), 25 hydroxyvitamin D (25 OHD), parathyroid hormone (PTH) and the urine calcium/creatinine ratio in a 2 h urine sample (UCa/UCreat) were measured. In the whole group sCa and the ratio uCa/ucreat were measured.


RESULTS
After 150,000 IU of vitamin D2 administration, serum 25 OHD levels at the end of winter (17.0 +/- 9.4 ng/ml) were similar to those at the beginning of autumn (18.7 +/- 10.7 ng/ml), but significantly higher from those obtained in a previous study without vitamin D (9.8 +/- 3.8 ng/ml, P < 0.001). PTH levels were higher at the end of winter (P < 0.02), but this augmentation was lower than the increment observed without vitamin D. Plasma calcium levels and the urine calcium/creatinine ratio were lower at 5 months after vitamin D2 dose (P < 0.02 and P < 0.05 respectively). In the total group the serum calcium was lower after the fifth month (P < 0.05). The Uca/Ucreat ratio was lower at 6 w and 5 mon (P < 0.05 and P < 0.001).


CONCLUSIONS
A single dose of 150,000 IU of vitamin D maintained appropriate levels of 25 OHD without inducing hypercalcemia nor hypercalciuria, but a winter increment of PTH (smaller than in the group without vitamin D) was not inhibited.
Oliveri
B
B
Sección Osteopatías Médicas, Hospital de Clinicas, Universidad de Buenos Aires, Argentina.
Cassinelli
H
H
Mautalen
C
C
Ayala
M
M
D000469:Alkaline Phosphatase / Q000097:blood; D001118:Argentina; D002112:Calcifediol / Q000097:blood; D002118:Calcium / Q000097:blood / Q000652:urine; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000652:urine; D004872:Ergocalciferols / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D011446:Prospective Studies; D012621:Seasons; D014808:Vitamin D Deficiency / Q000517:prevention & control*
D004872:Ergocalciferols; D010281:Parathyroid Hormone; D010758:Phosphorus; D003404:Creatinine; D000469:Alkaline Phosphatase; D002112:Calcifediol; D002118:Calcium