Changes of leucine-rich alpha 2 glycoprotein could be a marker of changes of endoscopic and histologic activity of ulcerative colitis

Leucine-rich alpha 2 glycoprotein (LRG) is one of the serum biomarkers for disease activity of ulcerative colitis (UC). We focused on the correlation between the changes of LRG and the changes of endoscopic and histologic activity of UC, in comparison to the changes of fecal calprotectin (Fcal), fecal immunochemical test (FIT), and C-reactive protein (CRP). Seventy-nine patients with two or more colonoscopies were enrolled, and 123 paired colonoscopies and 121 paired biopsies were examined. With regard to the change of endoscopic/histologic activity between the preceding and subsequent colonoscopy, there was improvement (n = 29/45), unchanging (n = 63/36), and worsening (n = 31/40). The correlations between the changes of marker levels and endoscopic/histologic activity were Fcal; r = 0.50/0.39 and FIT; r = 0.41/0.40, LRG; r = 0.42/0.40 and CRP; r = 0.22/0.17. Furthermore, when the correlation between the changes of LRG levels and the changes of endoscopic/histological activity was compared with those of other markers, the correlation of LRG tended to be superior to those of CRP (CRP vs. LRG; p = 0.08/0.01). LRG is equivalent to fecal markers and superior to CRP, when inferring changes in disease activity of UC based on changes in its level.