Background: Osteoprotegerin (OPG) may have proinflammatory roles in addition to its contribution to the maintenance of bone mass. Exclusive enteral nutrition (EEN) is an established therapy for the induction of remission in Crohn's disease (CD). The aims of this study were to ascertain serum, fecal, and mucosal expression of OPG in children with CD and to investigate the effects of EEN on OPG expression.
Methods: OPG was measured by enzyme-linked immunosorbent assay in serum, mucosal, and fecal samples collected from children with CD and controls. Fecal and Serum OPG was measured prior to and following 6-8 weeks of EEN therapy.
Results: Children with CD (n=82) and controls (n=45) were included. Mucosal and fecal OPG levels were elevated in CD compared to controls (P=0.018 and P<0.0001, respectively). Serum OPG was elevated in children with severe CD (P=0.005). Serum and fecal OPG levels dropped significantly following EEN therapy (P=0.0001 and P=0.002, respectively).
Conclusions: Increased serum and fecal OPG are seen in active CD and likely originate from the inflamed gut. Fecal and serum OPG decrease following EEN therapy. Further investigation of OPG and related proteins in the setting of IBD is now required.