S100A12 and irritable bowel syndrome: Both S100A12 (median 55.2 mg/kg) and calprotectin (1265 mg/kg) were elevated in the children with active IBD (n = 31) in contrast to the children without any inflammatory changes present (n = 30) (S100A12 median 1.1 mg/kg, P < 0.0001; calprotectin median 30.5 mg/kg; P < 0.0001).