Wahl TS, et al. - Researchers conducted a retrospective, population-based study in a cohort of patients with and without known preoperative renal dysfunction to evaluate preoperative urine protein levels as a biomarker for adverse surgical outcomes. An association was found between proteinuria and postoperative acute kidney injury (AKI) and 30-day unplanned readmission independent of preoperative estimated glomerular filtration rate (eGFR). Findings suggested that simple urine assessment for proteinuria might identify subjects at higher risk of AKI and readmission to guide perioperative management.