Cholesterol crystal embolization causing acute renal failure

Acute renal failure due to cholesterol embolization is a complication of severe generalized arteriosclerotic disease. It occurs spontaneously, or more often, as a complication of major medical or surgical procedures such as angiography and vascular surgery. The demonstration of characteristic cholesterol crystals in tissue biopsy specimens is a pathognomonic finding. However, renal cholesterol embolism may be clinically diagnosed when renal failure develops after known inciting factors or together with systemic manifestations of atheromatous embolization such as lower extremity livedo reticularis and focal digital ischemia. We report two cases of acute renal failure in which cholesterol embolization was found in skin and renal biopsies. One patient's renal function stabilized, but not to the basal level and the other patient developed end-stage renal disease.