Predictive value of fibrinogen in identifying inflammatory bowel disease in active stage

BACKGROUND: We aimed to externally validate for the first time the diagnostic ability of fibrinogen to identify active inflammatory bowel disease (IBD). METHODS: The research totally involved 788 patients with IBD, consisted of 245 ulcerative colitis (UC) and 543 Crohn’ s disease (CD). The Mayo score and Crohn disease activity index (CDAI) assessed disease activity of UC and CD respectively. The independent association between fibrinogen and disease activity of patients with UC or CD was investigated by multivariate logistic regression analyses. Area under the receiver operating characteristic curve (AUROC) assessed the performance of various biomarkers in discriminating disease states. RESULTS: The fibrinogen levels in active patients with IBD significantly increased compared with those in remission stage (P < 0.001). Fibrinogen was an independent predictor to distinguish disease activity of UC (odds ratio: 2.247, 95% confidence interval: 1.428–3.537, P < 0.001) and CD (odds ratio: 2.124, 95% confidence interval: 1.433–3.148, P < 0.001). Fibrinogen was positively correlated with the Mayo score (r = 0.529, P < 0.001) and CDAI (r = 0.625, P < 0.001). Fibrinogen had a high discriminative capacity for both active UC (AUROC: 0.806, 95% confidence interval: 0.751–0.861) and CD (AUROC: 0.869, 95% confidence interval: 0.839–0.899). The optimum cut-off values of fibrinogen 3.22 was 70% sensitive and 77% specific for active UC, and 3.87 was 77% sensitive and 81% specific for active CD respectively. CONCLUSIONS: Fibrinogen is a convenient and practical biomarker to identify active IBD.