Confocal Endomicroscopy Intestinal Epithelial Barrier Abnormalities in Individuals Without Documented Gastro-Intestinal Disease.

Background And Aims: Probe-based confocal endomicroscopy (pCLE) allows real-time microscopic visualization of the intestinal mucosa surface layers. Despite remission achieved through anti-tumor necrosis factor or vedolizumab therapy, anomalies in the intestinal epithelial barrier are observed in inflammatory bowel disease (IBD) patients. Our study aimed to assess these abnormalities in non-IBD individuals and compare them with IBD patients in endoscopic remission to identify the associated factors.

Methods: The study involved 84 patients, 40 with IBD under biologic therapy for over 6 months and in endoscopic remission, and 44 without IBD or irritable bowel syndrome (IBS) undergoing colorectal screening colonoscopy. White light endoscopy and probe-based confocal laser endomicroscopy were performed in the ileum, right colon, transverse colon, left colon, and rectum. Demographic, clinical, biological, and morphological factors were examined.

Results: pCLE revealed abnormalities in both non-IBD individuals and those with IBD in endoscopic remission, such as fluorescein leakage, blood vessel dilatation, and hypervascularization across all segments, as well as epithelial gaps in the ileum, and crypt dilatation in the colon. Comparing the two groups, IBD patients exhibited slightly more gaps in the ileum, increased fluorescein leakage in the transverse colon, and fewer vessel dilatation in the transverse colon. Abnormalities were more frequent in cases of hypertension (p = 0.03), dyslipidemia (p = 0.02), female gender (p = 0.02), selective serotonin reuptake inhibitor (p = 0.03), and family history of IBD (p = 0.04) or colorectal cancer (p = 0.03).

Conclusion: Confocal endomicroscopy abnormalities are present in both non-IBD individuals undergoing colorectal cancer screening colonoscopy as in those with IBD in endoscopic remission. Further research is needed to understand the pathophysiological mechanisms of these abnormalities and their clinical impact.