6327 An audit evaluating the appropriate use of vitamin D testing in children and adolescents at Alder Hey Children’s Hospital

Objectives Vitamin D is an important nutrient for bone health and growth.1 Deficiency can lead to rickets and bone deformities therefore Public Health England recommend vitamin D supplementation from birth to age four.2 A review has concluded that asymptomatic vitamin D testing has no role in adult populations3 however this has not been evaluated in paediatric patients. The primary audit aim was to review vitamin D testing at Alder Hey Children's Hospital against national and local guidelines, with a secondary aim assessing the clinical outcomes in patients with insufficient/deficient results. Methods Two cohorts aged 0–16 years were reviewed to represent seasonal variation of vitamin D testing practice: January 2022 (Winter) and July 2022 (Summer). The audit proforma combined local and national guidance from the Royal College of Paediatrics and Child Health and National Institute for Health and Care Excellence. Vitamin D results were classified as deficient (≤25nmol/L), insufficient (25–50nmol/L) or sufficient (≥50nmol/L). Test indications were categorised and assessed for appropriateness via the proforma, with all inappropriate indications categorised as asymptomatic tests. The clinical outcomes in insufficient/deficient patients were evaluated. Data was collected via the MediTech eNotes system. General practice requests, duplicate and control tests were excluded. Results Similar numbers of vitamin D tests were assessed within Winter (n= 453) and Summer (n=425) after exclusions. Insufficient/deficient vitamin D levels were detected in 29.4% of tests (n=125) in Summer compared to 61.1% (n=277) in Winter. Most patients were asymptomatic during testing at 56.5% in Winter (n=256) and 62.6% in Summer (n=266). For patients with appropriate indications, the largest categories were a) conditions affecting metabolism/absorption of vitamin D (Winter n=114; Summer n=79), b) abnormal associated investigations (Winter n=22; Summer n=26) and c) symptoms/signs of rickets/osteomalacia (Winter n=21; Summer n=10). In those with insufficient/deficient results (Winter n=277; Summer n=125), 65.7% in Winter and 56.0% in Summer received appropriate supplementation/treatment with vitamin D. Results were unacknowledged within the eNotes or prescription record for 28.9% of patients in Winter and 40.0% in Summer, notably in those receiving annual routine bloods. Conclusion Vitamin D results varied by season, but test indications remained reasonably consistent. This audit demonstrates a large proportion of asymptomatic tests, suggesting closer adherence to approved guidelines could avoid upsetting procedures for paediatric patients alongside cost saving. We suggest a review of inclusion of vitamin D testing in routine annual bloods by relevant specialist teams, discrete indication categories on electronic requests systems and departmental education. References Arundel P, Shaw N. 'Vitamin D and Bone Health: A Practical Clinical Guideline for Patient Management in Children and Young People' National Osteoporosis Society, 2018. National Institute for Health and Care Excellence 'Vitamin D deficiency in children'. 2022. McChesney C, Singer A, Duquette D, Forouhi NG, Levinson W. 'Do not routinely test for vitamin D' The British Medical Journal. 2022.