Readmission with Acute Kidney Injury Following Ileostomy: Patterns and Predictors of a Common Phenomenon

Purpose Ileostomy is associated with various complications, often necessitating rehospitalization. High-output ileostomy is common and may lead to acute kidney injury (AKI). Here we describe the temporal pattern of readmission with AKI following ileostomy formation and identify risk factors. Methods Patients that underwent formation of ileostomy between 2008 and 2021 were included in this study. Readmission with AKI with high output ileostomy was defined as readmission with serum creatinine > 1.5-fold compared to the level at discharge or latest baseline (at least stage-1 AKI according to Kidney Disease: Improving Global Outcome (KDIGO) criteria), accompanied by ileostomy output > 1000 ml in 24 h. Patient characteristics and perioperative course were assessed to identify predictors for readmission with AKI. Results Of 1191 patients who underwent ileostomy, 198 (16.6%) were readmitted with a high output stoma and AKI. The mean time to readmission with AKI was 98.97 ± 156.36 days. Eighty-six patients (43.4%) had early readmission (within 30 days), and 66 (33%) were readmitted after more than 90 days. Over 90% of patients had more than one readmission, and 110 patients (55%) had 5 or more. Patient-related predictors for readmission with AKI were age > 65, body mass index > 30 kg/m 2 , and hypertension. Factors related to the postoperative course were AKI with creatinine > 2 mg/dl, postoperative hemoglobin < 8 g/dl or blood transfusion, albumin < 20 g/dl, high output stoma and need for loperamide, and length of hospital stay > 20 days. Factors related to early versus late readmissions and multiple readmissions were also analyzed. Conclusions Readmission with AKI following ileostomy formation is a consequential event with distinct risk factors. Acknowledging these risk factors is the foundation for designing interventions aiming to reduce frequency of AKI readmissions in predisposed patient populations.