Cholesterol Emboli SyndromeDz

Synonyms: Multiple cholesterol emboli syndrome, pseudovasculitis.

ICD-9 Code: 445.0; affecting the kidney, 593.83.

Definition: Cholesterol emboli syndrome is an uncommon complication of atherosclerosis with obstruction of small arteries and arterioles by cholesterol crystals. Symptoms are caused by embolization from ulcerated or denuded large vessel plaques and may mimic systemic necrotizing vasculitis.

Demographics: Cholesterol emboli syndrome occurs in adults (>50 years of age) with advanced atherosclerotic vascular disease, frequently after angiographic or other invasive vascular procedures. It may also follow anticoagulation or thrombolytic therapy. The lower aorta is the most common source of emboli.

Cardinal Findings: Skin and renal manifestations predominate. Skin manifestations include livedo reticularis, “blue toes,” splinter hemorrhages, ulcerations, purpura/petechiae of the lower extremities, or gangrene. Renal impairment may initially be subacute but can progress over weeks to months to severe renal insufficiency. As many as 40% of patients may require dialysis. Less common clinical features include ischemia of the gut leading to perforation or hemorrhage and CNS involvement manifest as amaurosis fugax or stroke. Constitutional symptoms such as fever, weight loss, myalgias, and fatigue are occasionally seen and add to the difficulty in differentiating this entity from systemic necrotizing vasculitis.

Diagnostic Testing: Laboratory test findings are nonspecific and include elevated acute-phase reactants (ESR and CRP) and eosinophilia. Urine may reveal granular or hyaline casts, proteinuria, and eosinophiluria. Skin, muscle, or, less commonly, renal biopsy specimens show pathognomonic findings of cholesterol clefts in the lumina of small vessels. Arteritis varies from a mild inflammatory response to obliterative endarteritis. Diagnosis is made premortem in only 30% to 40% of cases.

Therapy: Anticoagulation is contraindicated and, if already initiated, should likely be discontinued. It may be helpful to locate and resect the source of emboli. A role of steroid therapy has not been established. Treatment is largely supportive. Mortality may be as high as 60% to 90% because of renal involvement and frequent comorbidities.

BIBLIOGRAPHY

Hauben M, Norwich J, Shapiro E, et al. Multiple cholesterol emboli syndrome—six cases identified through the spontaneous reporting system. Angiology 1995;46:779–784.PMID:7661380

Scolari F, Tardanico R, Zani R, et al. Cholesterol crystal embolism: a recognizable cause of renal disease. Am J Kidney Dis 2000;36:1089–1109.PMID:11096032