Endocrine Abstracts

Background: Fractures are reported in 1/3 of children who have been abused. The Royal College of Paediatrics and Child Health (RCPCH) recommends that assessment of fractures where there is suspicion of physical abuse should include bone biochemistry: calcium (Ca), phosphate (Ph), alkaline phosphatase (ALP), parathyroid hormone (PTH) and Vitamin D (VitD).

Objectives: To describe the pattern of bone biochemistry in children with fractures when non-accidental injury (NAI) is suspected.

Methods: A retrospective review of case notes, electronic results database, and radiology records over a ten-year period (2012- 2021) at the Royal Hospital for Children, Glasgow (RHCG). Children who were under two years of age who had undergone a skeletal survey as part of a child protection investigation where one or more fractures were identified were included. Established criteria to classify NAI were used to distinguish confirmed NAI from non-NAI. Bone biochemical markers were classified as normal or abnormal using local reference ranges. VitD deficiency was classified as VitD <25nmol/l and insufficiency as 25-50nmol/l.

Results: One hundred and twenty children were identified, of whom 107 (89.2%) had bone biochemistry performed. Twenty-nine children (24.2%) had injuries that were classified as confirmed NAI. The remainder were classified as highly suspicious of NAI (n=7,5.8%), suspicious of NAI (n=14,11.7%), unexplained (n=16,13.3%) and accidental (n=54,45%). Forty-three (40.2%) children[am1] were identified as having either one or more abnormal bone biochemical markers. One child was found to be vitD deficient, a further 27/107 (25%) were found to be insufficient. In cases where NAI was confirmed either at case conference or by criminal conviction 14/29 (48.3[am²] %) had one or more abnormal bone biochemical markers. None of the children displayed clinical or radiological evidence of rickets.

Conclusion: Children undergoing investigation of a fracture in suspected NAI often have a vitD in the deficient or insufficient range in the absence of clinical, radiological, or biochemical evidence of rickets. Other bone biochemical markers are frequently outside the normal reference ranges in this population.