Can different types of retinal emboli be reliably differentiated from one another? An inter- and intraobserver agreement study

OBJECTIVE

To determine whether ophthalmologists can agree on the qualitative assessment of visible retinal emboli.

DESIGN

Inter- and intraobserver agreement study.

SETTING

The retina and vitreous subspecialty session at the 1996 Canadian Ophthalmological Society meeting.

SUBJECTS

A total of 42 observers, of whom 30 were retinal specialists.

OUTCOME MEASURES

The observers viewed 17 fundus photographs of 11 patients with embolic acute retinal artery occlusion and classified the visible retinal emboli into one of three groups: cholesterol, calcific or other.

RESULTS

Overall, there was slight agreement for the 17 observations (mean kappa = 0.063). The kappa statistic for all cases ranged from slight to fair agreement. Slight interobserver agreement for the six unique photographs was observed (mean kappa = 0.073). Slight intraobserver agreement was found for the three photographs that were shown in different orientations (mean kappa = 0.041) and for the two photographs shown with differing magnification (mean kappa = 0.102).

CONCLUSIONS

Overall both intraobserver and interobserver agreement on the qualitative assessment of retinal emboli was poor. With only slight agreement on the classification of emboli, systemic evaluation of acute retinal artery occlusion should not be based on qualitative assessment of retinal emboli.

[Livedo reticularis, acral necroses and renal failure. Cholesterol crystal embolisms]

In a 67 year old patient with multiple cardiovascular risk factors a livedo reticularis, ischemic acral lesions as well as deterioration of renal function five weeks after cardiac catheterism and aorto-coronary bypass surgery led to suspicion of cholesterol embolism. Fundoscopy revealed cholesterol crystals in retinal vascular branches thus delivering important diagnostic information. Atheromatous lesions of the entire aorta and the ilio-femoral arteries were possible sources for embolism. The outcome was favorable. The lesions of the toes regressed and renal failure did not progress to dialysis. The diagnostic steps taken, the clinical picture of cholesterol embolism, the use of imaging and therapeutic options are discussed.

Cholesterol crystal embolism. Case report

A 60-year-old man presented with a cholesterol crystal embolism that gave a rather confusing clinical picture. An immediate multidisciplinary approach established the diagnosis and the rapid, dramatic skin loss that exposed vital structures over his thigh and lower leg was reconstructed by an ipsilateral inferior pedicled rectus abdominis musculocutaneous flap with a lateral oblique cephalad fasciocutaneal component. The case, which a plastic surgeon would rarely encounter, is interesting because of the diagnostic approach and the management.

Use of a prostacyclin analogue in cholesterol crystal embolism

The prognosis of cholesterol embolism is often poor, and no treatment is presently available. We report the use of a stable prostacyclin analogue in treating cholesterol embolism in a diabetic patient with arteriopathy. As a sole therapy, it improved cutaneous manifestations and pain, in parallel with an increased transcutaneous oxymetry. We think that prostacyclin analogues are novel candidates for the treatment of cholesterol embolism.

Pulmonary cholesterol crystal embolization

BACKGROUND

Cholesterol crystal embolization (CCE) has been documented to affect nearly every organ system. However, CCE involving the lung is distinctly uncommon and has been documented only in the setting of an aortocaval fistula.

DESIGN

A case at the Massachusetts General Hospital and a MEDLINE search of English-language medical articles published between 1966 and 1997 provide the basis for this report.

RESULTS

The precipitants of CCE include invasive vascular procedures, anticoagulant therapy, and thrombolysis. The most common symptoms include claudication of the calf, gastrointestinal bleeding, and weight loss. The most common signs include livedo reticularis, gangrene, and ulcers. Azotemia, proteinuria, normocytic anemia, and eosinophilia often are found. Herein is described the first pathologically confirmed case of CCE to the lung in the absence of an arteriovenous fistula.

CONCLUSION

Pulmonary hemorrhage should now be included in the diverse list of presenting signs of CCE. Moreover, CCE should be considered in the differential diagnosis of pulmonary-renal syndromes.

Cholesterol emboli syndrome--uncommon or unrecognized?

Cholesterol emboli syndrome is a multisystem disorder that can be precipitated by angiographic procedures. We report 5 cases in which the presentation was renal failure. All patients had undergone angiography, but the temporal relation of the procedure to the clinical presentation was highly variable, the interval ranging from one day to four months. With the increase in diagnostic and therapeutic uses of angiography, the cholesterol emboli syndrome is likely to become more frequent and needs to be recognized.

[Atheroembolic disease (cholesterol crystal embolism)]

The atheroembolic disease, often non recognized and fatal in the elderly, is a complication of atherosclerosis characterized by obstruction of multiple small arteries by cholesterol crystals. It may occur spontaneously or after aortic wall trauma, latter usually following angiography or cardiovascular surgery, and the use of anticoagulants. Renal failure, livedo reticularis and acrocyanosis of the lower extremities have been frequently described. In some cases the clinical picture may resembling a vasculitis. The diagnosis can be confirmed by skin, muscle or kidney biopsy. In practice, the treatment is symptomatic. The most effective measure is prevention.

[Cholesterol crystal embolisms: an exciting search for "pearls"]

This article is meant to increase the interest in an often forgotten clinical entity. Cholesterol emboli are in the majority of cases only diagnosed at post-mortem examination. Even though the triad livedo reticularis, renal failure and eosinophilia constitutes its most prominent feature, the variable clinical manifestations of this disorder with multiorgan involvement ("pseudovasculitis") make the search for cholesterol crystals particularly exciting. The discovery of 10 cases of cholesterol emboli over 2 years in a regional hospital's internal medicine department demonstrates that this occurrence is not rarely and that its accurate identification can be particularly relevant. It is important to recognize this disease since it is often iatrogenic, affects elderly people with atherosclerosis of the large vessels and causes high morbidity and mortality.

Cholesterol emboli: a common cause of renal failure

Cholesterol embolization (CE), usually occurring in males in their sixth or seventh decade of life, can affect multiple organ systems, including the kidney. Interventive diagnostic procedures and aortic surgery greatly increase the risk of CE. Rapid or insidious progression of renal failure in association with surgical or diagnostic radiologic procedures should suggest this diagnosis. Progressive renal insufficiency in older patients with generalized arterial disease should suggest ischemic nephropathy secondary to bilateral renal artery stenosis, renal CE, or both. Recent worsening of hypertension is characteristic of either diagnosis. A number of clinical conditions can simulate renal CE, and final differentiation may be possible only by renal biopsy. Aggressive, supportive management of renal CE is warranted because renal function may stabilize and, in a limited number of cases, may even improve.

Nephrotic-range proteinuria in renal atheroembolic disease: report of four cases

The protean clinical manifestations of atheroembolic disease (AED) mimic systemic disorders with kidney involvement. Acute or chronic renal failure develops spontaneously or more frequently after an inciting event in patients with AED. Significant proteinuria and nephrotic syndrome, however, constitute uncommon findings. We present four patients with AED documented histopathologically who developed nephrotic-range proteinuria. The mechanisms of proteinuria are discussed, and it is suggested that AED be considered in the differential diagnosis of nephrotic syndrome in elderly patients with serious vascular disease.

Evaluation and management of cholesterol embolization and the blue toe syndrome

The blue toe syndrome is characterized by tissue ischemia secondary to cholesterol crystal or atherothrombotic embolization leading to occlusion of small vessels. Embolization occurs typically from an ulcerated atherosclerotic plaque located in the aorto-iliac-femoral arterial system. Clinical presentation can range from a cyanotic toe to a diffuse multiorgan systemic disease that can mimic other systemic illness. Mortality can be higher than 70% depending on the scope of the illness. Embolization can occur spontaneously or from a variety of insults such as invasive vascular procedures, anticoagulation, or thrombolytic therapy. Angiography, duplex ultrasonography, computerized tomographic scanning, and magnetic resonance imaging have been used to image the offending lesions, with angiography considered the "gold standard" despite its inherent risks. Recently, transesophageal echocardiography has been shown to be a helpful tool in imaging the thoracic aorta and delineating in great detail the anatomy of the aortic atheroma. At present, surgery remains the most viable treatment option. However, we look to the future for large randomized trials to help predict embolization and thus the proper medical therapy.

Cholesterol emboli may mimic systemic vasculitis

Images

Microembolization from atheroembolic disease or aneurysm. A case study

Cyanosis of the digits may have several etiologies ranging from trauma to connective tissue disease; however, the most common cause of the so-called blue toe syndrome is atheroembolic disease or aneurysm and is frequently misdiagnosed on initial presentation. Pedal pulses are often palpable which may misdirect the physician from a diagnosis of vascular pathology. Furthermore, the proximal source of embolic shower may be far from the sight of symptoms. Noninvasive vascular testing, peripheral angiography, abdominal and popliteal ultrasonography, and echocardiography are all techniques that may be beneficial in discovering the origin of emboli. Atheroembolisms and aneurysms can be limb-threatening or life-threatening and hence early diagnosis is imperative.

Redefining the incidence of clinically detectable atheroembolism

BACKGROUND AND OBJECTIVES

Atheroembolism, caused by peripheral embolization of small cholesterol crystals that fracture off of ruptured atherosclerotic plaques in the major vessels, leads to multifocal ischemic lesions and progressive tissue loss. The end result is often ischemic injury in the skin, kidney, brain, myocardium, and intestine, but any organ distal to the culprit lesion may be affected. The precise incidence of this serious clinical syndrome has been difficult to ascertain from the available literature, but it appears to be much more common than has been assumed. The objective of the present study is to clarify the incidence of atheroembolism among inpatients in an acute hospital setting.

PATIENTS AND METHODS

We surveyed inpatient nephrology consultations during a 7-month period from January through July 1994. From a pool of 402 consultation charts, 99 were identified with two or more substantive risk factors for atheroembolism. The records of 85 of these patients were available for careful review. More than 300 additional patients were found to have ICD-9 discharge codes for other vascular conditions, but we were unable to confirm that any of these were in fact cases of atheroembolism, since there is no specific ICD-9 discharge code for this entity. In the 85 cases reviewed, a diagnosis of atheroembolism was made only if the patient had identifiable substantive risk factors, suggestive physical findings, and supporting laboratory results.

RESULTS

Eleven of the 85 surveyed records documented strong evidence supporting a "probable" diagnosis of atheroembolism. Tissue was examined in 4 of these 11, resulting in definitive histologic confirmation in 3. Another 5 of the 85 surveyed records were "suggestive" of atheroembolism. Altogether, atheroembolism was a likely diagnosis in a total of 16 cases during this 7-month period, or 1 case in every 2 weeks. These cases comprised 19% of nephrology consultations in which 2 or more risk factors were present, or 4% or all nephrology consultations. The patients' records confirmed the serious implications of clinically detectable atheroembolism. Several patients underwent lower extremity amputation, nearly half required acute or chronic dialysis, and more than half died within several months of diagnosis

CONCLUSIONS

The present study suggests that at least 4% of all inpatient nephrology consultations, representing approximately 5% to 10% of the acute renal failure encountered, involve clinically significant atheroembolism. Patients with atheroembolism appear at a rate of at least 1 case every 2 weeks. They often have identifiable substantive risk factors at initial consultation, and probably represent only the most severe cases of atheroembolism. In view of the serious implications of this basically untreatable syndrome, heightened awareness and preventive maneuvers in the population at risk are essential.

Cholesterol crystal embolization in the Netherlands

OBJECTIVE

To clarify the incidence and clinical features of cholesterol crystal embolization (CCE).

METHODS

Analysis of the relevant data of 842 diagnosed cases of CCE filed in the Dutch National Pathology Information System from 1973 through 1994.

RESULTS

No report of CCE was recorded from 1973 through 1979. Since then, its incidence rose from 0.9 case per million population in 1980 to 6.0 cases per million population in 1985, but stabilized thereafter. Among autopsy reports, the relative percentage of CCE was similar over the years, with 0.35% in 1982 and 0.30% in 1994 (mean 0.31% range, 0.20% to 0.42%). Nine patients in whom CCE was found in their renal transplant were excluded from the study. Thus, among a total of 833 elderly (mean age, 72.1 years), predominantly male (73.9%) patients, 1066 CCE sites were found in 323 biopsy reports, 264 resection reports, and 287 autopsy reports.

CONCLUSION

In the Dutch population, CCE is reported steadily, with an average frequency of 6.2 cases per million population per year since 1985. It occurs predominantly in elderly men with a history of atherosclerotic disease and hypertension. Symptoms may be absent, go unrecognized, or mimic other disease processes. It can also be a coincidental finding. The primary CCE site is the kidney, followed by the skin and gastrointestinal tract.

Cholesterol crystal embolisation to the alimentary tract

The features of cholesterol crystal embolisation (CCE) to the alimentary tract were studied by retrospective analysis of the clinical and pathological data of 96 patients (70 men, 26 women, mean age 73.8 (58-95) years) with this diagnosis in the Dutch national pathology information system (Pathologisch Anatomisch Landelijk Geautomatiseerd Archief (PALGA)) from 1973-92. In the 96 patients, 130 CCE sites were found throughout the alimentary tract, mostly in the colon (42.3%). Most patients had a history of atherosclerotic disease and presented with abdominal pain, diarrhoea, or gastrointestinal bleeding, sometimes after surgical or radiological vascular procedures. A number were taking oral anticoagulant treatment. The diagnosis of CCE had been considered before the histological diagnosis in only 11 patients. In the remaining cases, ischaemic colitis, tumour, and inflammatory bowel disease were suggested in the differential diagnosis. A premortem diagnosis of CCE was made in 70.8% of the cases. In 24 of the 35 necropsy examinations, CCE seemed to be directly or indirectly related to the cause of death. It is concluded that in this unselected, homogenous group of patients, CCE sites were most frequently found in the colon. They generally presented with abdominal pain, diarrhoea, and gastrointestinal blood loss. CCE often mimicked common gastrointestinal disease, leading to incorrect diagnosis.

Renal vascular lesions in the elderly: nephrosclerosis or atheromatous renal disease?

In white Europeans, renal size and function decline with age. This phenomenon has long been attributed to nephrosclerosis, i.e. primary vascular lesions associated with glomerular obsolescence, tubulointerstitial lesions and fibrosis. The part played by ageing and by pre-existing hypertension is still a matter of debate. Nephrosclerosis is a diagnosis of exclusion when no renal histology is available. As renal biopsy is rarely carried out in an elderly patient with atrophic kidneys, a long history of hypertension and only microalbuminuria or no proteinuria, the diagnosis of nephrosclerosis is generally overestimated. Even when renal histology is available, only subtle differences in vascular lesions have been claimed to distinguish those due to ageing from those due to hypertension. At any rate, meticulous control of blood pressure is certainly the most efficient means of protecting the renal vessels from further deterioration. Atheromatous renal disease has more recently been recognized as a major cause of progressive renal failure in the elderly. Renal artery stenoses due to atheromatous plaques might well be the cause of 10-15% of end-stage renal failure in whites aged > 50 and be the fourth cause of uraemia in this age group. Such stenoses are usually bilateral and developing. Present imaging methods, such as duplex ultrasound scanning and renal scintigraphy, are valuable means of diagnosis. Renal angioplasty can halt the the pace of renal insufficiency, or even durably improve it in nearly half of the cases. Finally, aorto-renal atheroma is a common and underestimated cause of cholesterol embolism. Minor, spontaneous forms thereof are indistinguishable from nephrosclerosis. Massive embolism entails a dismal prognosis, in terms of both renal function and patient survival. In conclusion, renal vascular lesions in the elderly remain a major concern. Improving non-invasive diagnostic procedures and applying preventative as well as curative measures should significantly reduce the incidence of end-stage renal disease is such patients.

[Systemic cholesterol embolism]

The authors report two cases of cholesterol embolism and review the literature on this subject. Cholesterol crystal emboli are very serious complication of atheroma, generally situated in the aorta and usually in patients in their sixties. The frequency of cholesterol embolism is 20% in autopsy studies in this population. The embolic process accounts for the polymorphic clinical feature. Clinical signs are always delayed in relation to triggering factors. The symptoms can sometimes simulate a systemic disease. Cutaneous signs are present in 40 to 75% of cases. Acute renal failure is present in 30% of cases. Other signs may also be observed: alteration of the general state, fever, neurological disorders, pain of the lower limbs, myalgia, gastrointestinal haemorrhage or perforation, ischaemic colitis, pancreatitis, mesenteric or coronary angina. A triggering factor is revealed in 80% of cases: aortic surgery, retrograde aortic catheterization, fibrinolysis or oral anticoagulant treatment. The prognosis is poor due to the clinical context, the patient's age and the absence of any specific treatment. The short-term mortality is 60 to 80% according to various series. The best treatment is prevention: carefully assess the indication for an endovascular procedure in an atheromatous patient; if necessary, perform transoesophageal ultrasonography to evaluate the risk; whenever possible change the incision in vascular investigations or operative procedures in high-risk patients.

Multiple cholesterol emboli syndrome--six cases identified through the spontaneous reporting system

Six cases of suspected multiple cholesterol emboli syndrome were identified by a review of reports contained in the company's records of adverse event reports. Antecedent risk factors in these reports included cardiac catheterization, thrombolytic therapy, translumbar aortography, renal arteriography, subclavian arteriography, abdominal aortography, and heparinization. Unlike the commonly reported subacute presentation, onset occurred during or immediately after catheterization in 5 of the 6 patients reported. Acute renal failure; hypertension; back, leg, and/or abdominal pain; and livedo reticularis were the events most frequently reported. Angiographers should consider multiple cholesterol embolization when multiple organ system dysfunction occurs during or immediately after intraarterial catheterization.

Atheromatous embolism: an unusual case of acute lower extremity ischemia

A case is presented of lower extremity ischemia related to atheromatous embolization that presumably occurred as a result of passage of an angiographic catheter through the aorta. The patient presented with signs and symptoms pathognomonic for this entity. Emergency physicians need to be aware of this unusual etiology for an ischemic lower extremity.

[Cholesterol embolism in the lower limbs]

An atheromatous aorta may be the source of micro-emboli composed of cholesterol crystals. These cholesterol emboli presumably result from dislodgment of atheromatous material occurring either spontaneously, or consecutively to a coronary angiography, an aortic surgery or even an anticoagulant or thrombolytic treatment. Even if the best known clinical feature is the "blue toe" syndrome together with renal insufficiency, the spectrum of disease caused by cholesterol emboli ranges from asymptomatic to rapidly progressive multiple system failure. Therefore cholesterol embolism is a serious complication of aortic atherosclerosis and often holds a poor prognosis. Diagnosis is confirmed by skin or muscle biopsy and fundoscopic examination. The optimal treatment remains to be established.

[Cholesterol embolism: a heavy price to pay after successful fibrinolysis]

We attribute a case of acute irreversible renal failure associated with "blue toe syndrome" and eosinophilia to a cholesterol embolism after "successful" treatment of myocardial infarction with fibrinolysis. This case shows that CE can be caused not only by invasive arterial procedures but also by thrombolytic as well as by anticoagulant treatment. In modern medicine, the importance of this often fatal but usually undetected systemic affection is increasing. For patients with serious atherosclerosis it is essential to analyze the risks and benefits before undertaking arterial invasive procedures or fibrinolysis.

[Cholesterol embolism: a diagnostic puzzle and a therapeutic dilemma]

A well documented and histologically proven case of cholesterol embolism is discussed, and the recent literature is reviewed. This disorder is usually underdiagnosed and commonly detected only at autopsy. Elderly people with atherosclerotic vascular disease are predominantly affected. Cholesterol embolization can occur spontaneously, but it often results from medical interventions such as arterial invasive procedures, vascular surgery, anticoagulation or thrombolytic therapy. Clinical manifestations are manifold, and two distinct patterns are generally observed: a mild peripheral cutaneous form and a severe visceral form that frequently mimics other systemic diseases. Transient eosinophilia is an important laboratory finding, and it is present in about 80% of the cases. Cholesterol crystals are rarely found in retinal arteries, and premortem diagnosis is established most commonly by biopsy of the muscle, skin or kidney. The role of various therapeutic modalities is still controversial and does not seem to change the course of this frequently fatal disease. The treatment is symptomatic, and the surgical correction of the embolic source is recommended only in the case of peripherally embolizing stenotic lesions. The most effective measures are prevention and the identification of patients at risk. In these patients the aforementioned precipitating events should be avoided, or the potential risk must be carefully weighed against the possible benefits in this particularly fragile group of patients.

[Renal insufficiency due to cholesterol embolism. 4 cases]

Atheroembolic disease is a complication of atheromatous disease and is quite often misunderstood. A precise diagnosis can be made difficult, by the lack of specific tests. The first case, in which we identified this disease, resulted from a bladder biopsy, in the instance of a patient with a suspected carcinoma. The experience, with this initial patient, led us to identification of a further 3 cases, within our previous 2 years case histories. One must consider the possibility of atheroembolic disease during the differential diagnosis of acute renal failure in geriatric patients, given the serious prognosis.

Cholesterol-embolism: diagnosis by endoscopy

A case report is presented, concerning a 68-year-old woman, with gastro-intestinal complaints, six weeks after an aortic arteriography. On gastroscopy a duodenal ulcer was found and multiple purple discolourations. Biopsies show that these discolourations were caused by cholesterol-emboli. As the patient's complaints resided quickly after treatment for duodenal ulcer, the cholesterol-emboli can be seen as incidental findings. The gastroscopical biopsies were an important clue to the diagnosis of the cause of the rapid progressive renal failure in this patient.

[Cholesterol embolism]

Two patients with advanced atherosclerotic vascular disease developed multiple cholesterol emboli. In both patients the clinical presentation included livedo reticularis of the lower part of the body and purple toes with small areas of distal necrosis and ulceration. The predisposing factors are operative vascular procedures and the use of anticoagulants respectively. Biopsy of skin lesions revealed characteristic cholesterol clefts within atheromatous debris filling small, deep arterial lumen. Multiple cholesterol emboli should be suspected in presence of cutaneous lesions and confirmed histologically in the appropriate clinical setting.

Position dependent livedo reticularis in cholesterol emboli syndrome

We describe a case of a 64-year-old Filipino man who presented with cholesterol emboli syndrome manifesting as worsening hypertension, renal failure and livedo reticularis involving the upper legs and lower abdomen. The livedo reticularis became very prominent with the patient standing, but completely vanished after several minutes of lying supine. Deep cutaneous biopsy of an area of skin that was found to be consistently involved with livedo reticularis demonstrated cholesterol clefts in several vessels, thus establishing the diagnosis in this patient, and avoiding the more problematic option of biopsying an involved visceral organ.

[A cholesterol embolism during heparin treatment]

The cholesterol embolization is a rare complication of atherosclerosis. A direct implication of the treatment with anticoagulants in the etiology of the disease has been questioned, and now such therapy is considered more as an adjuvant factor with angiographic procedures than as a cause. A 60-year-old patient with an ischemic cardiomyopathy presented cholesterol embolization syndrome, confirmed by cutaneous biopsy histologic examination during treatment with heparin. Spontaneous evolution was favourable and only limited amputation of the lower limbs were required. The authors think that cholesterol emboli have a direct relationship to the treatment with heparin in this case, there being no other causes to justify its appearance.