Renal cholesterol embolism: Analysis of two spontaneous autopsy cases

Abstract

Two cases of spontaneous cholesterol embolism, which followed different clinical courses, acute and chronic renal failure, are presented and histopathological lesions are compared. Both cases were diagnosed as cholesterol embolism post-mortem. Case 1 (a 66-year-old man) had acute onset of illness with fever, leucocytosis and renal failure, diagnosed as vasculitis, and died of rupture of an abdominal aortic aneurysm. Case 2 (an 84-year-old man) had eosinophilia of unknown aetiology for 7 years with intermittent worsening of renal function and died of sepsis. Case 1 had diffuse cholesterol crystal emboli in the interlobular arteries and arterioles of the kidney, but case 2 had patchy cholesterol emboli in the interlobular arteries of the kidney. The aorta of case 1 was diffusely ulcerated, which is in contrast to that of case 2, who had limited ulceration in thoracic aorta, which might have contributed to the long duration of illness. Immunohistochemically, the number of macrophages and T cells that infiltrated around cholesterol emboli in the arteries was more in case 1 (macrophages 27.7, T cells 36.1/mm(2)) than in case 2 (2.7, 1.38/mm(2)). Focal interstitial inflammation occurred in both cases. In case 1, marked tubulitis was observed. Case 2 had rather severe atrophy of the tubules and fibrotic interstitium where mast cells were rich (31.9/mm(2)). The number of B cells and eosinophils was few in case 2 (11.35, 0.7/mm(2)) compared with case 1 (101.9, 16.15/mm(2)). These results suggest that in acute lesions of renal cholesterol embolism, macrophages and T cells accumulate around cholesterol crystals and cause tubulointerstitial inflammatory lesions with other inflammatory cells. In chronic lesions, macrophages, T cells and mast cells are the major inflammatory cells present in the interstitium.

Spontaneous cholesterol embolisation causing acute renal failure

“…While there have been reported cases in the literature of spontaneous embolisation causing bowel infarction, 3 pulmonary fat embolism, 4 and cerebral infarction, 5 there were no reports on the occurrence of acute renal failure in those instances. Ehara et al 6 did, however, report on two autopsy cases of renal cholesterol embolism in patients who had presented with premortem acute renal failure. Similarly, Tanaka et al 7 found multiple cholesterol embolisation in a postmortem renal sample in a patient who died following presentation with severe hyperreninemic hypertension and renal insuffi ciency.…”

Colour-Doppler US evaluation of patients with hypertension and nephropathy

“…Indeed, most patients studied had severe impairment of renal circulation. These patients carry a poor prognosis, with 1-year mortality rates between 64% and 87%, and monitoring by imaging may certainly help the clinician deal with this complex disease given that angiography is strongly contraindicated both because it is an interventional manoeuvre and because it requires heparin administration [31][32][33]34].…”

“…Infatti, nella maggior parte dei pazienti giunti alla nostra osservazione era presente una severa compromissione del circolo renale. Questi sono pazienti a prognosi infausta con mortalità ad 1 anno variabile dal 64% all'87% in cui il monitoraggio strumentale può essere certamente di ausilio al clinico nell'affrontare una così complessa patologia, dal momento che in tali pazienti è fortemente controindicata l'angiografia, sia perché manovra interventistica sia per la somministrazione di eparina [31][32][33]34]. Nella paziente con la middle aortic syndrome l'ECD ha svelato l'alterazione emodinamica a livello renale, giustificando il ricorso a metodiche più panoramiche come l'angio-TC che ha rilevato la complessa situazione anatomica da cui era affetta [22][23][24].…”

Cholesterol embolization syndrome: report of two cases

“…Increased inflammation and eosinophilia may explain the efficacy of corticosteroid treatment reported in several cases. [18,19] Nevertheless, increased mortality with corticosteroid therapy has also been reported. [4] Another point of discussion in the management of CES is the safety and efficacy of anticoagulant and antiplatelet treatments.…”