Acute renal failure.

Acute renal failure is most commonly associated with renal ischemia, although nephrotoxins such as antibiotics, radiographic contrast media and anesthetic agents have become important causes. Although the pathophysiology has not been completely explained, renal vasoconstriction appears to be an important factor. Oliguria, isosthenuria and a urinary sodium concentration over 25 mEq per L are characteristic features. Control of volume and avoidance of metabolic disequilibrium can be accomplished by careful management and dialysis. The major causes of death are infection and the primary disease itself.