Today's approach to the critically ill patient with acute kidney injury.

The present review describes recent evidence on all aspects relating to acute kidney injury (AKI): epidemiology, definition, diagnosis, medical and extracorporeal therapy. AKI is often underrecognized, but its outcome still remains unfavorable. In this light, definition, classification and diagnosis of AKI are fundamental today and may be reliably based on recently proposed RIFLE (risk, injury, failure, loss of function, end-stage kidney disease) classification. Pharmacological therapy of AKI is still scarcely effective, but renal replacement therapy has progressed to a more accurate and safe treatment and new interesting high-level trials and observational studies have been performed and are reviewed and commented. In the near future, however, only increased awareness of AKI incidence and early treatment or prevention of kidney injury progression will hopefully improve outcome of critically ill patients with renal failure.