Acute renal failure: clinical aspects and pathophysiology.

Acute renal failure may be caused by multiple conditions including those which are due to some direct hemodynamic or nephrotoxic insult. In considering the pathophysiology of these entities, it seems appropriate to differentiate between the initiating and the maintenance phase of the disorder. In the former, renal ischemia and/or a direct effect of a given nephrotoxic agent seems to be the basis for the underlying renal damage. In the maintenance phase, renal functional impairment is maintained by a number of factors which include persistent renal vasoconstriction, tubular obstruction, a leakage of filtrate across damaged tubular epithelium, and a reduction in glomerular capillary permeability. The therapy and possible preventive aspects of these entities are discussed.