P527 Leucine-rich alpha 2 glycoprotein- A useful biomarker to discriminate mucosal healing in CRP-negative ulcerative colitis. (30th January 2023) - Tanaka, A
Abstract: Background: The long-term treatment goals for inflammatory bowel disease including ulcerative colitis (UC) have shifted from clinical remission to mucosal healing. However, frequent endoscopies are a great burden on the patients. Leucine-rich alpha 2 glycoprotein (LRG) is produced by hepatocytes, neutrophils, and the intestinal epithelium. Therefore, it is speculated to be more gut-specific than C-reactive protein (CRP) level. This study examined whether LRG could be used as a biomarker to determine the presence or absence of mucosal healing in patients with CRP-negative UC. Furthermore, we examined whether it was useful for each type of lesion extension. Methods: The subjects of this study were CRP-negative UC patients who visited our department from May 2021 to October 2022, had their LRG measured, and underwent imaging evaluation by colonoscopy. We analysed the patients' clinical background, the ROC-AUC of LRG for mucosal healing, the cut-off value of LRG to discriminate mucosal healing, and the cut-off value of LRG to discriminate mucosal healing by the type of extension of lesions. Endoscopic evaluation was performed within 3 months before and after the LRG measurement. The upper limit of the normal CRP value was set to <3 mg/L. Results: A total of 57 cases were analysed; 30 (53%) were men. The median age (range) of onset was 31.1 years (8-67 years). The median disease duration (range) was 6.8 years (0-40). Pancolitis occurred in 41 (72%) cases. Left-sided colitis and proctitis occurred in 16 (28%) patients. The median (range) LRG was 11.2 μg/ml (6.5-34.4 μg/ml). The ROC-AUC of LRG for mucosal healing was 0.576 (95% confidence interval 0.441-0.711). The cut-off value of LRG for discriminating mucosal healing was 12.6 μg/ml (sensitivity 0.373, specificity 0.913). 3) The cut-off value for pancolitis was 12.6 (0.857, 0.439), and that for left-sided colitis or proctitis was 9.4 (0.556, 0.800). Conclusion: In CRP-negative UC patients, LRG can be used as a biomarker for discriminating between the presence and absence of mucosal healing. It may also help distinguish types of extension.