Although serum S100A12 was significantly increased in the children with CD (median 239 (27–14,810) ng/mL), the median level was higher in those with UC (median 750 (247–1391) ng/mL) and not elevated in the IBD unclassified group (median 94 (40–294) ng/mL). Here, S100A12 is linked to inflammatory bowel disease.