Objective: S100A12 is a pro-inflammatory protein which is secreted by granulocytes. S100A12 serum levels increase during inflammatory bowel disease (IBD). We performed the first study analyzing fecal S100A12 in adults with signs of intestinal inflammation.
Methods: Fecal S100A12 was determined by ELISA in fecal specimens of 171 consecutive patients and 24 healthy controls. Patients either suffered from infectious gastroenteritis proven by stool analysis (65 bacterial, 23 viral) or underwent endoscopic and histological investigation (32 with Crohn`s disease, 27 with ulcerative colitis, 24 with irritable bowel syndrome; IBS). Intestinal S100A12 expression was analyzed in biopsies obtained from all patients. Fecal calprotectin was used as an additional noninvasive surrogate marker.
Results: Fecal S100A12 was significantly higher in patients with active IBD (2.45 ±1.15 mg/kg) compared to healthy controls (0.006 ±0.03 mg/kg; p <0.001) or patients with IBS (0.05 ±0.11 mg/kg; p <0.001). Fecal S100A12 distinguished active IBD from healthy controls with a sensitivity of 86% and a specificity of 100%. We also found excellent sensitivity of 86% and specificity of 96% for distinguishing IBD from IBS. Fecal S100A12 was also elevated in bacterial enteritis but not in viral gastroenteritis. Fecal S100A12 correlated better to intestinal inflammation than fecal calprotectin or other biomarkers.
Conclusions: Fecal S100A12 is a novel noninvasive marker distinguishing IBD from IBS or healthy individuals with a high sensitivity and specificity. Furthermore, S100A12 reflects inflammatory activity of chronic IBD. As a marker for neutrophil activation, fecal S100A12 may significantly improve our arsenal of noninvasive biomarkers of intestinal inflammation.
- disease activity
- fecal markers