Fecal calprotectin concentration has been reported to be increased in preterm infants with NEC and may be an accurate marker for early diagnosis of NEC [31], [32] Consistent with these reports, we found that ileal S100A9 expression was lower in both the LA and EG groups vs. EA group (Experiments 1 and 2). This evidence concerns the gene S100A9 and necrotizing enterocolitis.