Chapter 67 - Vitamin D Deficiency and Nutritional Rickets in Children

Abstract

Nutritional rickets remains a global public health problem, despite effective and inexpensive means to prevent and treat the disease. It is most prevalent in the infant/toddler age groups and the adolescent, but vitamin D deficiency is also prevalent in women of child bearing age, resulting in babies being born with low vitamin D stores and the mothers having inadequate vitamin D in breast milk, thus exacerbating the risk for rickets in these infants. In a number of subtropical developing countries, rickets appears to be due to low-dietary calcium intakes (∼200mg/day) rather than vitamin D deficiency. Biochemically these children are differentiated from those with vitamin D deficiency by having markedly elevated serum 1,25-dihydroxyvitamin D concentrations and high fractional intestinal calcium absorption. Nutritional rickets represents the outcome of a spectrum of causes ranging from vitamin D deficiency on one hand to dietary calcium deficiency on the other, while in between low dietary intakes and vitamin D insufficiency combine to cause the disease.