Two cases of cholesterol crystal embolism nephropathy and literature review

To analyze the clinical and pathological characteristics of two patients with cholesterol crystal embolism nephropathy (CCEN) following vascular interventional procedures, and to explore its diagnosis and individualized management strategies. Case 1: A 75-year-old male presented with significantly elevated serum creatinine levels 7 months after endovascular repair of an abdominal aortic aneurysm. This was accompanied by marked eosinophilia and purpuric lesions on the soles. A skin biopsy revealed cholesterol crystals within the dermal arteries, confirming the diagnosis of cholesterol crystal embolism (CCE). Given concomitant right peroneal vein thrombosis, anticoagulation with rivaroxaban was initiated alongside anti-inflammatory glucocorticoid therapy. Following treatment, the skin lesions resolved and renal function stabilized. Case 2: A 70-year-old male developed gradually increasing serum creatinine levels after endovascular repair of an aortic arch aneurysm, accompanied by eosinophilia, systemic edema, and plantar livedo reticularis. A renal biopsy demonstrated cholesterol crystals in the arterioles, confirming CCEN. Glucocorticoid treatment was discontinued due to the onset of gastrointestinal bleeding; nevertheless, the cutaneous embolic signs subsequently subsided and renal function stabilized. These two cases suggest that the development of subacute renal impairment after vascular intervention, particularly when accompanied by eosinophilia and cutaneous embolic signs, is highly suggestive of CCE. Tissue biopsy remains the cornerstone for definitive diagnosis. The mainstay of treatment involves the early initiation of glucocorticoid therapy, the application of which should be individualized to carefully balance potential benefits against the risks of bleeding and the management of comorbidities.