Crystal-induced acute renal failure

Several medications-notably acyclovir, sulfonamides, methotrexate, indinavi r, and triamterene-are associated with the production of crystals that are insoluble in human urine. Intratubular precipitation of these crystals can lead to acute renal insufficiency. Many patients who require treatment with these medications have additional risk factors, such as true or effective intravascular volume depletion and underlying renal insufficiency, that inc rease the likelihood of drug-induced intrarenal crystal deposition. Acute r enal failure in this setting may be preventable if it is anticipated by app ropriate drug dosing, volume expansion with high urinary flow, and alkalini zation of the urine when appropriate. Renal failure may be reversible if th e drug is discontinued, and by volume repletion and alkalinization of the u rine when appropriate. Management of established renal insufficiency includ es volume repletion, dialytic support if necessary, adjustment of drug dose s, and avoidance of further exposure to nephrotoxins. (C) 1999 by Excerpta Medica, Inc.