Vitamin D status in hospitalized black children under 2 years of age.

The apparent decline over the last decade of vitamin D deficiency rickets among black infants in South Africa has suggested a significant improvement in their vitamin D status. Levels of serum 25-hydroxy-vitamin D, calcium, phosphorus and alkaline phosphatase, together with a radiograph of the left wrist, were obtained in 114 hospitalized black infants under the age of 2 years in order to establish the frequency of infants with or at risk of vitamin D deficiency. Mean 25-hydroxyvitamin D levels were found to be in the low normal range and showed no correlation with either age or season. Vitamin D stores were depleted in 7% and relatively deficient in 20,7% with suggestive radiological features of rickets in only 2 patients. The high prevalence of malnutrition and infection made a biochemical assessment of rickets impossible. The significance of these suboptimal vitamin D levels is uncertain, but the available literature would suggest that these infants are at increased risk of developing vitamin D deficiency rickets.

Is craniotabes a pathognomonic sign of rickets in 3-month-old infants?

Fifty-eight well Black infants between the ages of 10 and 15 weeks were examined for the presence of craniotabes and investigated for the presence of vitamin D deficiency and rickets. Thirty-five infants were found to have craniotabes and 5 of these had radiological evidence of rickets. No difference in dietary history, birth weight, weight gain, length or skull circumference was found between those with and those without craniotabes. Significantly more females than males had craniotabes. The majority of infants with craniotabes had normal biochemical values. Craniotabes is a common finding in 3-month-old infants and is of no help in diagnosing rickets in this age group.