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/m², 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.