Colorectal ESD and acute kidney injury: a rare but clinically relevant adverse event, a cohort study of 1,537 patients.

Background and aims Colorectal endoscopic submucosal dissection (ESD) is increasingly used as a curative treatment for large neoplastic lesions. Although bleeding and perforation are well described, the risk of acute kidney injury (AKI) after colorectal ESD remains unknown. We aimed to evaluate the incidence, risk factors and outcomes of AKI following colorectal ESD in a large single-centre cohort. Methods All colorectal ESD procedures performed in our Unit between January 2017 and December 2024 were prospectively recorded. Demographic, lesion-related, and procedural data were collected at the time of intervention. Comorbidities, chronic medications (including angiotensin-converting enzyme [ACE] inhibitors), peri-procedural fluid management, intra-procedural hypotension, and laboratory values (pre- and post-ESD serum creatinine) were retrospectively extracted from electronic health records. AKI was defined according to KDIGO criteria within 72 hours of ESD. Baseline characteristics, procedural variables, and outcomes were compared between patients with and without AKI. Variables with significant associations were entered into multivariable logistic regression to identify independent predictors of AKI. Results Among 1,537 patients (median age 70 years; 57.5% male), en bloc and R0 resection rates were 96.2% and 89.1%, respectively. AKI occurred in 20 patients (1.3%) within 72 hours of ESD. Compared with patients without AKI, those with AKI were older (median 74 vs. 70 years) and more frequently received ACE inhibitor therapy (40% vs. 13.6%). ASA score and other comorbidities were not significantly associated with AKI. Lesions in the AKI group were larger [100 (70–150) vs. 55 (45–70) mm] and more commonly located in the rectum (70% vs. 34%). AKI was also associated with longer procedure duration (181 vs. 55 minutes), higher perforation rates (35% vs. 10%), and increased bleeding (36% vs. 5%). On multivariable analysis, lesion diameter (OR 1.03 per mm increase) and pre-procedural ACE inhibitor therapy (OR 3.96) remained independently associated with AKI. Although all patients eventually recovered baseline renal function—with only one requiring short-term dialysis—AKI was associated with significantly longer hospital stays (median 9 vs. 1 day). Conclusions AKI following colorectal ESD is uncommon but clinically significant, leading to prolonged hospitalization. Larger lesion size, longer procedure duration, and pre-procedural ACE inhibitor therapy identify patients at higher risk. Preventive measures, including optimized peri-procedural hydration, careful monitoring of urine output, and temporary discontinuation of ACE inhibitors, should be considered, particularly for lengthy or complex procedures.