Recommendations for vitamin D supplementation for subjets between 2 and 18 years offer strong sequential doses of vitamin D: 2 times 100 000 units in spaced winter period of 3 months. Data from the literature show a further increase in the incidence of oxalo-calcium stones in children and adolescents associated with hypercalciuria with training Randall plates, essential step lithogenesis calcium oxalate. Knowing the links between vitamin D and urinary calcium excretion, these data lead to the question of increased sensitivity in some children with vitamin D, sensitivity could explain these situations with hypercalciuria increase the gallstone risk. This increased sensitivity to vitamin D may unmask particularly if inputs of high doses of vitamin responsible then a transient hypercalciuria with development of microcrystals.

Inclusion Criteria:

• Children aged 2 to 17 years included
• Obtaining informed consent of the parents signed
• Participants aged 18 years included