Decreased serum iron concentration and total iron binding capacity are associated with serious Crohn's disease.

This study aimed to investigate whether serum indicators related to iron stores in the body are associated with clinical and endoscopic disease severity. Eighty-four patients with Crohn's disease (CD) and twenty-four healthy volunteers were included. The indicators related to iron stores were detected within one week after endoscopic and CT enterography examinations. Patients were divided into three groups according to the CDAI(Crohn's disease activity index)scores. Serum iron levels were decreased in all groups (p < 0.05), and the values of remission group were higher than those of moderate group (p < 0.001). The total iron binding capacity(TIBC)values of the moderate group were lower than those of the controls and the other groups (p < 0.05). None of the indicators differed significantly among the patients classified by SES-CD (p > 0.05). Underweight, decreased serum iron and TIBC were independent risk factors for moderate clinical disease. Combined detection of decreased serum iron and TIBC was helpful in differentiating severe patients. The sensitivity and specificity were 32.7% and 100%, respectively (AUC = 0.812, p < 0.01). Decreases in serum iron and TIBC were associated with the clinical activity of CD. Combined detection of the two indicators was conducive to screening serious disease.