Abstract Background Reliable early biomarkers that predict long-term outcomes of advanced therapies in ulcerative colitis (UC) remain an unmet clinical need. We previously developed a deep learning stool image model (DLSUC) capable of predicting endoscopic activity based on smartphone-captured stool photographs. This study evaluated whether DLSUC can serve as an early predictive indicator of clinical outcomes in patients initiating advanced therapies. Methods Patients with moderate to severe UC who started biologic agents or small-molecule therapies were prospectively enrolled. Participants submitted weekly smartphone stool photographs for three months after treatment initiation. Clinical relapse during follow-up was assessed using Kaplan–Meier analysis, comparing relapse risk between groups classified as active versus inactive by DLSUC at 3 months. Results Fifty-six patients were included (mean age 40 ± 14.5 years; 67.9% male). Baseline fecal calprotectin (Fcal) and C-reactive protein (CRP) levels were 1305 mg/kg (median, IQR 521–3343) and 0.5 mg/dL (median, IQR 0.17–2.26), respectively. The median ulcerative colitis endoscopic index of severity (UCEIS) was 5 (IQR 4–6). Infliximab was the most commonly initiated therapy, followed by JAK inhibitors, vedolizumab, ustekinumab, and ozanimod. Over a median follow-up of 9 months, 22 patients (39.3%) experienced clinical relapse. Patients categorized as active by DLSUC using 3-month stool images had a significantly higher relapse risk than inactive patients (log-rank p 0.0001, Fig. 1). Fcal at 3 months also differentiated relapse risk (log-rank p 0.0001), whereas CRP did not (log-rank p 0.05). Conclusion A deep learning model applied to smartphone stool images may provide a practical, noninvasive tool to predict early clinical outcomes in UC patients initiating advanced therapies. This approach could complement established biomarkers and enhance personalized treatment monitoring. Reference: 1. Lee JW, Woo D, Kim KO, et al. Deep Learning Model Using Stool Pictures for Predicting EndoscopicMucosal Inflammation in Patients With Ulcerative Colitis. Am J Gastroenterol 2025;120:213-224. Conflict of interest: Prof. Dr. Kim, Eun Soo: No conflict of interest Lee, Hyun Seok: No conflict of interest Kim, Sung-Kook: No conflict of interest Kim, Kyeong Ok: No conflict of interest Jang, Byung Ik: No conflict of interest Lee, Yoo Jin: No conflict of interest Chung, Yun Jin: No conflict of interest Bae, June Hwa: No conflict of interest Kim, Eun Young: No conflict of interest
Kim et al. (Thu,) studied this question.