Endoscopic indigo carmine spraying for evaluation of intestinal mucosal permeability: A prospective pilot study

• Published in: Endoscopy International Open
• Main Authors: Hirokazu Fukui, Shojiro Kikuchi, Noriyuki Ojima, Tomonori Yokoyama, Masataka Ikeda, Shinichiro Shinzaki
• Format: Journal Article
• Language: English
• Published: Georg Thieme Verlag KG
• ISSN: 2364-3722; 2196-9736
• DOI: 10.1055/a-2697-7599

Background ‘Leaky gut’, caused by increased mucosal permeability, plays a pivotal role in various diseases. However, few methods are available to evaluate intestinal mucosal permeability in the living human body. We established a novel method for evaluation of mucosal permeability using indigo carmine (IC). Methods Subjects undergoing colonic endoscopy for screening of colon polyps or evaluation of ulcerative colitis (UC) severity were enrolled. IC was endoscopically sprayed in the cecum, and blood samples were obtained before spraying and at 30 and 60 min after. The level of serum IC was analyzed by LC/MS equipped with a Nexera HPLC system. Results In both the control (subjects screened for colon polyps) and UC groups, all subjects showed their highest serum IC levels at 30 min after spraying. The serum IC level was significantly higher in UC patients than in the controls at both 30 min and 60 min after spraying. In the UC group, serum IC levels at both 30 min and 60 min were significantly higher in patients with a Mayo endoscopic subscore (MES) 1 at the cecum than in those with MES 0 in the same area. Conclusions Endoscopic spraying with IC is useful for evaluation of intestinal mucosal permeability.