Deep Ulcers in Acute Ulcerative Colitis at Index Endoscopy Predict Corticosteroid Resistance

Background: Ulcerative Colitis (UC) is a chronic inflammatory disease affecting the colon. Its acute form can be life-threatening, necessitating hospital admission and intravenous (IV) corticosteroid treatment. This study aimed to predict IV corticosteroid response in acute UC patients based on endoscopic findings at admission. Methods: Individuals admitted to the hospital for acute UC for intravenous corticosteroid treatment were selected. Those with gastrointestinal infections and those without endoscopy at admission were excluded. Results: A retrospective analysis was conducted on a cohort of 62 patients, of which 25.8% did not respond to IV steroids. No significant associations were found between demographic, clinical, and laboratory parameters and corticosteroid response at admission. Rectosigmoidoscopy was performed for all patients upon hospitalization, and the Mayo Endoscopic Score (MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) were obtained. The results revealed significant differences in median UCEIS scores between non-responders and responders (7, IQR 3 vs. 5, IQR 1, p=0.011). Notably, a UCEIS score of ≥5 demonstrated a sensitivity of 100% in identifying patients who did not respond to corticosteroids, although with a lower specificity of 22.7%. Furthermore, the MES exhibited a statistically significant association with treatment response (p=0.002), with a MES≤2 having a negative predictive value of 92.9% for IV steroid resistance. Importantly, the presence and type (small vs. large) of ulcers at the initial endoscopy were found to be the most effective predictive factor for corticosteroid response (AUC=0.745; 95%CI=0.594-0.896; p=0.005), as 57.1% of patients with deep ulcers were non-responders. Conclusions: The importance of evaluating ulcer severity during endoscopic assessment in patients with acute ulcerative colitis is underscored by our findings. Specifically, the presence of deep mucosal ulcerations should prompt consideration for intensifying therapy.