Endocrine Abstracts

Background and aims: Rickets is a childhood condition resulting from impaired mineralisation of the growth plate, resulting in bony deformities. A retrospective survey was undertaken to identify causes of rickets in children treated at the Royal Manchester Children’s Hospital from 2009 to 2014.

Methods: Cases of rickets were identified through a search of all paediatric radiology reports containing the words ‘Rickets’ or ‘Osteomalacia’ and confirmed with reference to relevant biochemical tests. Those with serum 25OHD concentrations <50 nmol/l were classified as vitamin D deficiency rickets and those with 25OHD >50 nmol/l and a history of inadequate dietary calcium intake as calcium deficiency rickets.

Results: Seventy-nine cases of rickets were identified of which 68 patients had nutritional rickets. Four children had rickets due to dietary calcium deficiency and the rest of the cases of nutritional rickets were primarily due to vitamin D deficiency (mean 25OHD 10.8±10.3). Three of the cases with calcium deficiency rickets had cow’s milk protein allergy and the fourth disliked and avoided dairy products. The relevant biochemical data are shown in the Table below.

Conclusions: Rickets due to dietary calcium deficiency has been reported in South Africa, Northern Nigeria, Bangladesh, and parts of India. Whilst vitamin D was the commonest cause of nutritional rickets in our survey, we also identified four cases of rickets due to dietary calcium deficiency. This survey highlights the importance of providing adequate calcium supplements in children with food allergies/intolerances.