By measuring the serum concentration of hepcidin by ELISA, we observed that the concentrations of hepcidin were higher in the sera of active IBD patients compared with those in remitted IBD patients (P < 0.0001 in A-UC vs. R-UC and P < 0.0001 in A-CD vs. R-CD) and healthy controls (HC) (P < 0.0001 in A-UC vs. HC, and P < 0.0001 in A-CD vs HC), while no difference in serum hepcidin was detected between IBD patients in remission stage and healthy controls (Figure 1(a)). This evidence concerns the gene HAMP and inflammatory bowel disease.