In terms of the accuracy of FC in detecting IBD, a study involving 139 patients who underwent a diagnostic ileocolonoscopy revealed significantly higher fecal levels of lactoferrin (Lf), Cal, PMN-e, and serum CRP in individuals with UC or CD with active inflammation compared to those with inactive inflammation and patients with irritable bowel syndrome (IBS) (all p < 0.05). This evidence concerns the gene CRP and irritable bowel syndrome.