Intestinal Fatty Acid Binding Protein (I-FABP) as a Promising Test for Crohn's Disease: A Preliminary Study

Background: Crohn's disease (CD) is a chronic inflammatory bowel disease that can affect any part of the gastrointestinal tract from the mouth to the anus. The clinical course presents with remissions and activations. Also, clinical findings or endoscopic activity do not always reflect the overall appropriate disease activity. This is why specific markers are always an issue of concern for the diagnosis, prediction of relapse, and monitoring of CD activity. Fatty acid binding proteins (FABPs) are intracellular proteins that are expressed abundantly in several tissues. Intestinal FABP (I-FABP) is a plasma and urine marker that indicates intestinal damage. In this preliminary study, we aimed to determine whether serum I-FABP levels are a useful marker for CD. Methods: Seventy-four patients with CD (41 active and 33 in remission) and 37 healthy controls were included in the study. The level of serum I-FABP was determined by ELISA. Crohn's disease activity index (CDAI) and CRP were used to assess the activity of Crohn's disease and to evaluate whether IFABP is a useful laboratory marker. Results: Serum I-FABP levels of patients with active disease were observed to be statistically higher than patients in the remission and control groups (p = 0.012 and p = 0.038, respectively). No statistically significant difference was observed among patients in the remission and control groups (p = 0.145). Correlation analysis showed a positive correlation between I-FABP and CDAI (r = 0.319, p = 0.006). In addition, a positive correlation was found between CRP and I-FABP levels. Conclusions: I-FABP seems to be a useful systemic marker for CD activity.