Endocrine Abstracts

Retrospective data collection was performed for all of the paediatric vitamin D (25-hydroxycolecalciferol) serum samples analysed over the preceding 13 months. Around 300 requests were made for vitamin D sampling by various medical professionals including paediatricians (72%), general practitioners (13%), and orthopaedic surgeons (16%). 231 samples, costing £9 per sample, were analysed on 200 patients, predominantly for clinical indications such as growing pains, tuberculosis, and growth failure, amongst others.

Of the 200 patients 112 (56%) were vitamin D insufficient (≤50 nmol/l), of which 25 (22%) were severely deficient (≤20 nmol/l). A significant majority of the vitamin D insufficient patients are of Asian origin (58%), from the inner city, and from deprived areas (full analysis awaited). Bone profiles were sent with vitamin D analysis in the majority of patients: corrected calcium (Ca: n=81; 72%), inorganic phosphate (IPH: n=62; 55%), alkaline phosphatase (ALP: n=80; 71%). 8 of 81 (10%) patients with vitamin D insufficiency had hypocalcaemia; phosphate was normal in all patients. ALP was raised in 4 of 80 (5%) patients, of which only 1 was associated with hypocalcaemia. There was no difference in Ca, IPH or ALP between the insufficient and severely deficient group.

This analysis has demonstrated significant levels of vitamin D deficiency and insufficiency in the paediatric population of Peterborough. The cost implications of testing and management of vitamin D insufficiency is likely to be significantly higher than prevention through supplementation.

There is increasing evidence demonstrating involvement of vitamin D in immunity – particularly in relation to tuberculosis, carcinogenesis, and autoimmunity. It is imperative that a consensus is reached by paediatric endocrinologists regarding definition and treatment of vitamin D insufficiency, and more widely, prevention of insufficiency by supplementation or fortification.