Cholesterol Embolic Renal Disease: Experience of a Large Healthcare System.

Context. To determine the clinical-pathological features associated with cholesterol embolic renal disease, and review of literature. Design. This retrospective case series includes patients with cholesterol embolic renal disease (10 of 3087 kidney biopsies) who were diagnosed at Northwell Health, New York, between July 2017 and October 2022. Results. Cholesterol embolic renal disease is a rare disease with a prevalence of 0.32%. Four of 10 patients had intravascular interventional radiology procedures within 6 months prior to kidney biopsy. Four patients had remote interventional radiology history (6 months to 4 years). Seven patients presented with acute kidney injury; 3 patients underwent renal biopsy due to proteinuria. The average baseline creatinine was 2.0 ± 0.9 mg/dL; the creatinine at kidney biopsy and at follow-up was 4.3 ± 3.0 mg/dL and 2.8 ± 1.3 mg/dL, respectively. Eight patients had elevated serum eosinophil counts. Three patients died (mortality rate 30%) in an average follow-up of 4 months (range: 1-10 months). One patient progressed to end-stage kidney disease. The presence of cholesterol clefts is a hallmark of atherosclerotic emboli. Cholesterol clefts were present on the specimen for light microscopy (H&E and special stains) in 9 biopsies; 7 patients had cholesterol clefts in vascular lumens and/or walls. Cholesterol clefts were present on semi-thin sections for electron microscopy examination in 4 biopsies. One patient had cholesterol clefts present in semi-thin sections only. Conclusions. The clinical manifestation of cholesterol embolic renal disease in patients without recent intravascular interventional radiology history can be indolent but is associated with high mortality. Careful examination of all levels with light microscopy, including the perirenal tissue, and semi-thin sections can increase the detection rate of cholesterol embolic renal disease.