Ischemic acute tubular injury describes a lesion of simplification of the tubules, which commonly manifests clinically as a rapid loss of glomerular filtration rate, often with oliguria, granular casts, and low-level proteinuria. Ischemic acute tubular injury may occur at any age, with varying underlying causality. Isolated acute tubular injury is often recoverable; however, the prognosis is poor if part of multiorgan failure. Episodes of ischemic acute tubular injury are now recognized to increase risk of chronic kidney disease long-term.