Fecal beta-defensin-2 in children with inflammatory bowel diseases.

Defensins, endogenous antibiotic peptides, are part of the intestinal epithelial barrier. In this pilot study we analyzed the possibility of measuring fecal beta-defensin-2 (HBD2) in comparing inflammatory and noninflammatory conditions. In samples from healthy control individuals, low levels of HBD2 were detectable, which markedly rose under inflammatory conditions (P = 0.0002 vs normal control individuals), the highest levels being observed in patients with ulcerative colitis (median 356 ng/g, range 40-527). Despite frank inflammation, Crohn disease patients with colitis had significantly lower, albeit enhanced, HBD2 levels than did ulcerative colitis patients. These data confirm the possibility of quantifying HBD2 in feces and indicate that colitis in Crohn disease and colitis in ulcerative colitis differ from each other with respect to their ability to secrete HBD2.