We have previously analyzed these fecal biomarkers in ELBW infants demonstrating (i) that fecal calprotectin (fCP) levels depend on gestational and postnatal age and have a lower limit [13], (ii) that fecal S100A12 has an improved sensitivity and specificity for the detection of NEC when compared to fCP [14], and (iii) that high fecal and intestinal hBD2 concentrations, reflecting a strong intestinal immune response, were associated with a moderate course of NEC in ELBW infants [15]. This evidence concerns the gene S100A12 and necrotizing enterocolitis.