Acute renal failure from multiple myeloma precipitated by ACE inhibitors

Renal failure in multiple myeloma can be precipitated during hemodynamic perturbances of renal blood flow, as seen secondary to volume depletion, radiocontrast dye, and nonsteroidal anti-inflammatory agents. We report two cases of acute renal failure that developed suddenly after initiation of angiotensin-converting enzyme (ACE) inhibitor, both with biopsy-proven cast nephropathy. ACE inhibitors may contribute to the intratubular light chain cast formation and acute "myeloma kidney" in susceptible patients.