Leither MD, et al. - Whether outpatient acute kidney injury (AKI), defined by a 50% increase in creatinine (Cr), is related to increased mortality and renal events, was determined herein. The reported prevalence of outpatient AKI was more, relative to inpatient AKI. Moreover, outpatient AKI was recognized as a risk factor for all-cause mortality and renal events, even among those who recover kidney function.