P170 Faecal osteoprotegerin correlates with disease activity and predicts disease relapse in paediatric inflammatory bowel disease
F. De Voogd*1, L. Burgess2, R. Gearry3, A. Day2
1University of Otago, Paediatrics/Gastroenterology, Christchurch, New Zealand, 2University of Otago, Paediatrics, Christchurch, New Zealand, 3University of Otago, Gastroenterology, Christchurch, New Zealand
In addition to a key role in bone turnover, osteoprotegerin (OPG) also contributes directly to inflammatory processes. Work has shown that faecal OPG measurements reflect intestinal inflammation in inflammatory bowel disease (IBD). This study aimed to ascertain the relationships between faecal OPG and standard indicators of active inflammation in paediatric IBD and to elucidate the potential role of OPG in prediction of disease relapse in the following months.
Children aged 18 years or less with known IBD were recruited prospectively (n = 70). Disease activity index scores (n = 279), blood samples (n = 261), and stool samples (n = 316) were collected at baseline and then every 3 months. Standard disease activity index scores and serum inflammatory markers were ascertained at each time-point. An enzyme-linked immunoassay was used to measure OPG in stool samples.
Overall mean faecal OPG levels were greater in patients with active Crohn’s disease (CD) than in patients in remission (997 ± 1 630 v s 366 ± 739 pg/mL; p = 0.0006). Further, in these children, faecal levels of OPG correlated significantly with ESR (r = 0.3528, p < 0.0001), platelet count (r = 0.3417, p < 0.0001), and albumin (r = −0.1914, p = 0.004). Children in remission with faecal OPG levels of 83 pg/ml or greater had a higher risk of relapse in the subsequent 6 months (HR 3.025, p = 0.0135). In contrast, no significant correlation was found between UC disease activity index scores and faecal OPG concentrations.
This study demonstrated significant correlations between faecal OPG and disease activity in children with CD. Further, assessment of faecal OPG levels assist in the prediction of subsequent disease relapse. Additional studies are required to investigate further correlations between faecal OPG and other indicators of disease activity before the inclusion of faecal OPG measurement in clinical settings.