Acute kidney injury

Acute kidney injury (AKI) is defined as an acute deterioration of renal function within 7 days. It rarely occurs in an outpatient setting but is relatively common in hospitalized patients. An AKI leads to high short-termand also long-term mortality. Other relevant consequences of AKI include a higher risk of developing chronic kidney disease (CKD), arterial hypertension, heart failure and peripheral arterial occlusive disease. Many different causes can lead to AKI; the etiology is classically categorized into prerenal, renal and postrenal causes, depending on the origin. For some of these causes specific treatment exists (e.g. relieving urinary tract obstruction by urine drainage or immunosuppressive therapy in autoimmune-related AKI). In contrast, there is no causal treatment for acute tubular damage, which is the typical consequence of reduced renal perfusion due to hemodynamic instability. In these cases treatment is merely supportive.