Early change in serum leucine-rich α-2-glycoprotein predicts clinical and endoscopic response in ulcerative colitis.

Background/aims: Leucine-rich α-2-glycoprotein (LRG) is a new serum biomarker reflecting the disease activity of ulcerative colitis (UC), but its change during the acute phase has not been enough investigated.

Methods: Patients with UC who initiated the induction therapy with steroid or advanced therapy (biologics or Janus kinase inhibitors) were prospectively enrolled. Associations of LRG, C-reactive protein (CRP) and fecal calprotectin (FC) at baseline, week 1, and week 8 with clinical remission at week 8 and subsequent endoscopic improvement within 1 year (Mayo endoscopic subscore of 0 or 1) were assessed.

Results: A total of 143 patients with UC were included. LRG and CRP at week 1 were significantly lower in the clinical remission group than in the non-remission group (LRG, 20.6 μg/mL vs. 28.4 μg/mL, P< 0.001; CRP, 0.9 mg/dL vs. 2.3 mg/dL, P< 0.001) while FC demonstrated the difference between groups only at week 8. The area under the curves of week 1 LRG, CRP, and FC for week 8 clinical remission using the receiver operating characteristic curves analysis were 0.68, 0.71, and 0.57, respectively. Furthermore, LRG and CRP predicted subsequent endoscopic improvement as early as week 1, while FC was predictive only at week 8.

Conclusions: LRG can be an early-phase biomarker predicting subsequent clinical and endoscopic response to induction therapy.