Background-Systemic exposure to lipopolysaccharide (LPS) has been linked to clinical disease activity in adults with IBD. We hypothesized that markers of LPS exposure and the acute phase response (APR) would be increased in pediatric IBD patients with growth failure, and that LPS signaling would be required for induction of the APR in murine colitis.

Patients with CD with elevated GM-CSF Ab exhibit an increase in bowel permeability relative to patients with CD with lower levels of GM-CSF Ab in the absence of differences in systemic or intestinal inflammation. Therapies that target the mucosal barrier may be of particular benefit in this subgroup of patients with CD.

Background-Growth failure remains a common complication of pediatric Crohn Disease (CD), and has been associated with small bowel involvement and need for surgery. We have reported that patients with elevated (≥ 1.6 mcg/mL) Granulocyte Macrophage Colony Stimulating Factor auto-antibodies (GM-CSF Ab) are more likely to experience complicated ileal disease requiring surgery. We hypothesized that concurrent GM-CSF Ab and CARD15 risk allele carriage (C15 + GMAb + ) would be associated with growth failure in CD, and growth hormone (GH) resistance in murine ileitis.