Pulmonary cholesterol crystal embolization

Cholesterol embolization syndrome and intra-abdominal bleeding immediately after initiation of hemodialysis: a case report with literature review

Background

Cholesterol embolization syndrome (CES) is a disease associating with the systemic cholesterol crystal embolism and end-organ dysfunction due to the atherosclerotic plaque rupture, which is dominantly triggered by the intravascular intervention. There is no consensus for which types of anticoagulants we should use during the hemodialysis in patients with CES and end-stage renal disease.

Case presentation

We had a 68-year-old man with CES due to intravascular intervention, who suffered the omental bleeding, instead of the embolism, immediately after the initiation of hemodialysis with heparinization. An emergent laparotomy found active bleeding from the omentum, which was surgically repaired. The histopathological analysis showed the embolization of cholesterol crystal clefts in the omentum artery and the injury of arterial wall structure accompanied by the infiltration of inflammatory cells. We preferred nafamostat mesylate during hemodialysis and he had no adverse events following the surgery.

Conclusions

It should be noticed that, in addition to the embolic events, bleeding events can develop in patients with CES, particularly following the initiation of hemodialysis with anticoagulation therapy.

Cholesterol-embolization syndrome: current perspectives

Cholesterol-embolization syndrome (CES) is a multisystemic disease with various clinical manifestations. CES is caused by embolization of cholesterol crystals (CCs) from atherosclerotic plaques located in the major arteries, and is induced mostly iatrogenically by interventional and surgical procedures; however, it may also occur spontaneously. Embolized CCs lead to both ischemic and inflammatory damage to the target organ. Therefore, anti-inflammatory agents, such as corticosteroids and cyclophosphamide, have been investigated as treatment for CES in several studies, with conflicting results. Recent research has revealed that CES is actually a kind of autoinflammatory disease in which inflammasome pathways, such as NLRP3 and IL1, are induced by CCs. These recent findings may have clinical implications such that colchicine and IL1 inhibitors, namely canakinumab, may be beneficial in the early stages of CES.

Atheromatous embolization

Atheromatous embolization is a multisystem disease complicating advanced atherosclerosis. It occurs most often as a complication of angiography, an endovascular procedure or cardiovascular surgery. Atheromatous embolization can present in a subtle manner where it is often under-recognized, or with catastrophic results including myocardial infarction, strake or acute renal failure. It may mimic other disease processes and often goes underdiagnosed and undertreated. A high clinical suspicion is the key to diagnosis. Atheromatous embolization results in significant morbidity and mortality; therefore, early recognition followed by aggressive management may help to prevent end-organ damage and improve overall clinical outcomes. Management strategies should include risk factor modification, prevention of further insults by discontinuing or avoiding predisposing factors, supportive treatment and interventional or surgical approaches to remove the atheroembolic source. Atheromatous embolization is expected to increase as our population ages and the epidemics of diabetes mellitus and obesity increase.

Giant Cell Lesions of Lungs: A Histopathological and Morphometric Study of Seven Autopsy Cases

INTRODUCTION

Macrophages undergo fusion to form multinucleated giant cells (MGC) in several pathologic conditions. The exact mechanism of their generation is still unclear. MGC are a common feature of granulomas that develop during various inflammatory reactions.

AIM

To study the histopathological features of giant cell lesions in lungs and correlate the characteristics of giant cells with other histopathological findings. Also, to determine the utility of morphometry to differentiate foreign body and Langhans MGC.

MATERIALS AND METHODS

Seven cases were analysed. Specimen of lungs was grossed, sectioned and processed. Routinely, tissue sections were stained by Haematoxylin and Eosin (H&E) stain. Polarizing microscopy and special stains were employed in selected cases. Granulomas and MGC were counted and measured. Several other parameters like location, distribution, type and number of MGC, associated predominant inflammatory component and nature of granulomas were analysed.

RESULTS

Five patterns of lesions were observed in seven cases. Aspiration pneumonia was seen in three cases (42.85%) and constituted the most common pattern. However, aspiration pneumonia as the only cause of MGC was seen in only one case (14.28%). Pulmonary tuberculosis and asteroid bodies constituted two cases (28.57%) each. Cryptococcal pneumonia and cholesterol clefts constituted one case (14.28%) each. Crypococci were demonstrated to be positively birefringent by polarized microscopy on Ziehl-Neelsen stained sections. Based on statistical analysis of morphometric data, a new index (NP index) was proposed to statistically categorize MGC into foreign body type and Langhans type. NP index value of ≤0.016 was found to be statistically significant (p<0.005) in foreign body MGC. It had high sensitivity and efficacy.

CONCLUSION

MGC may not be always associated with granulomas. The mechanisms that lead to the occurrence of MGC, independent of granuloma needs to be elucidated. Morphometry may serve as a useful aid. But a pathologist has to rely on the morphological details to categorize MGC.

[A case of cholesterol embolization syndrome with cognitive impairment and pulmonary hemorrhage]

A seventy-year-old man developed color change in his left toes and was treated for frostbite. Eight months later, he developed cognitive impairment and was admitted to our hospital. A remarkable increase of eosinophils was observed in peripheral blood. Brain MRI revealed abnormal lesions in the fornix, corpus callosum, basal ganglia and frontal lobe. Steroid therapy ameliorated his symptom temporarily, but he suddenly developed cardiopulmonary arrest. His autopsy revealed severe pulmonary hemorrhage with alveolar vasculitis and cholesterol crystals in the brain, kidneys, liver, and the other organs. It was possible that cholesterol embolization to multiple organs including the brain induced systemic vasculitis that caused pulmonary hemorrhage and his critical prognosis. Cholesterol embolization should be considered when we see a patient with brain lesions accompanied with eosinophilia.

Fatal pulmonary embolism after hemodialysis vascular access declotting

Patient: Male, 59

Final Diagnosis: Pulmonary embolism

Symptoms: Cardiac arrest • chest pain • dyspnea

Medication: —

Clinical Procedure: Angioplasty

Specialty: Nephrology

Pulmonary Embolic Disorders

Deaths due to pulmonary thromboemboli are frequently encountered by the forensic pathologist and account for a significant percentage of sudden, unexpected deaths. Diagnosing these straightforward cases is often not a challenge, but unfortunately some cases in which a thromboembolism is expected can become complicated. Occasionally, a postmortem clot may mimic a thromboembolism and lead to a mistaken diagnosis, and in other situations it may become paramount to attempt to age a thrombus as part of a medicolegal lawsuit. Additionally, many individuals use the less specific term, “pulmonary emboli”, when referring to these cases in which a portion of a thrombus, usually originating in the deep veins of the lower extremities, breaks off and travels to the pulmonary vasculature bed where it occludes vessels and leads to a rapid demise. One must remember, though, that several other materials and tissues including fat, amniotic fluid, air, tumors, solid organs, synthetic materials, and parasites may be displaced and embolize to the lungs and cause significant disease. In the following pages we will provide a thorough review of pulmonary embolic disorders, focusing on those diseases most likely to be encountered by the forensic pathologist. The aim of this review is to aid the pathologist in using proper terminology, diagnosing various types of embolic disorders, and recognizing potential mimics.

Atheroembolic renal disease with rapid progression and fatal outcome

Atheroembolic renal disease is caused by foreign-body reaction to cholesterol crystals flushed from the atherosclerotic plaques into the small-vessel system of the kidneys. It is an underdiagnosed entity, mostly related to vascular procedures and/or anticoagulation, and prognosis is considered to be poor. Besides the benefit of aggressive medical prevention of further embolic events, use of steroid therapy has been associated with greater survival. Here we report a case of a patient with a multisystemic presentation of the disease days after performance of percutaneous coronary intervention and anticoagulation initiation due to an episode of myocardial infarction. Renal, cutaneous, ophthalmic, neurological, and possibly muscular and mesenteric involvement was diagnosed. Although medical treatment with corticosteroids and avoidance of further anticoagulation was applied, the patient rapidly progressed to end-stage renal disease requiring hemodialysis and died 6 months after diagnosis. This is a case of catastrophic progression of the disease resistant to therapeutic measures. Focus on diagnosis and more efficient preventive and therapeutic protocols are therefore needed.

Atheroembolic renal disease

Atheroembolic renal disease develops when atheromatous aortic plaques rupture, releasing cholesterol crystals into the small renal arteries. Embolisation often affects other organs, such as the skin, gastrointestinal system, and brain. Although the disease can develop spontaneously, it usually develops after vascular surgery, catheterisation, or anticoagulation. The systemic nature of atheroembolism makes diagnosis difficult. The classic triad of a precipitating event, acute or subacute renal failure, and skin lesions, are strongly suggestive of the disorder. Eosinophilia further supports the diagnosis, usually confirmed by biopsy of an affected organ or by the fundoscopic finding of cholesterol crystals in the retinal circulation. Renal and patient prognosis are poor. Treatment is mostly preventive, based on avoidance of further precipitating factors, and symptomatic, aimed to the optimum treatment of hypertension and cardiac and renal failure. Statins, which stabilise atherosclerotic plaques, should be offered to all patients. Steroids might have a role in acute or subacute progressive forms with systemic inflammation.

Pulmonary Vascular Disease

The pulmonary vasculature is an anatomic compartment that is frequently overlooked in the histologic review of lung biopsy samples, other than those obtained specifically to assess pulmonary vascular disease.1 Though often of a nonspecific nature, the histologic pattern of vascular remodeling may at times suggest its underlying pathogenesis and provide clues to the cause of pulmonary hypertension.2 Disproportionately severe vascular pathology may further indicate alternate disease processes, such as congestive heart failure or thromboemboli, contributing to the patient’s overall respiratory condition.

Pulmonary atheroembolism via an AV shunt

Although cholesterol crystal embolism can present with diffuse visceral involvement, lung lesions do not occur unless there is left to right circulatory shunting. Pulmonary atheroembolism was confirmed by histology in an elderly male with recent end-stage renal failure (ESRF) due to atheroembolic renal disease, who presented with massive hemoptysis and intractable respiratory failure. At autopsy, atheromatous degeneration of the aorta was observed and acute cholesterol emboli found in the kidneys, spleen, liver, stomach and lung. Cholesterol clefts were seen in pulmonary arterioles, and ischemic alveolar damage was present. The pulmonary arteries had no atheromatous changes. Intrapulmonary, intracardiac, and aortocaval shunting were not present. Pulmonary atheroembolism arising from a dialysis fistula has not been previously reported.

Cholesterol crystal embolism: diagnosis and treatment

Cholesterol crystal embolization (CCE) is a dreaded complication of radiology, vascular surgery, and/or anticoagulation in patients with atherosclerosis and ulcerated aortic plaques. It also represents a cause of early graft failure and of poor results of renal artery surgery. Crystals lodge in small caliber renal arteries, where they induce early, transitory thrombosis followed by delayed, definitive obstruction by endarteritis, accompanied by evidence of inflammation and eosinophilia. Massive CCE leads to early oligoanuria. In subacute forms, renal insufficiency is often delayed by weeks or months following the triggering event. A third, chronic subset of CCE is easily mistaken for atherosclerotic renal ischemia and/or nephrosclerosis. The kidney is rarely the sole organ involved in acute/subacute forms, in which the central nervous system, the coronary arteries, the spinal cord, and the mesenteric and pancreatic blood supply compromise represent the main causes of death. Cutaneous, retinal, and muscle involvement allow diagnosis by inspection or scarcely invasive biopsies in about 80% of cases, whereas renal biopsy as the only diagnostic procedure is required in 20% of cases. Prevention is based on avoidance of endovascular radiology maneuvers, vascular surgery, and excess anticoagulation in atherosclerotic patients. Treatment of acute/subacute forms of renal insufficiency consisting of stopping anticoagulation and forbidding any new radiologic and/or vascular surgery procedure; treating hypertension with angiotensin 2 antagonists and vasodilators, strict volemic control by loop diuretics and ultrafiltration, along with parenteral nutrition and prednisone, has been credited with improved outcome. Iloprost may obtain favorable results. Statins definitely ameliorate the renal and patient's prognosis.

Cholesterol crystal embolization (CCE) after cardiac catheterization: a case report and a review of 36 cases in the Japanese literature

Cholesterol crystal embolization (CCE) is a complication of atherosclerosis. A 67-year-old Japanese man underwent coronary artery bypass grafting. After the surgery, he underwent coronary angiography via the right femoral artery. Twelve days later, he suddenly developed acalculous cholecystitis and was treated with antibiotics. Gradual deterioration in renal function, purplish discoloration of the distal portion of his toes, and eosinophilia were noted. We performed a skin biopsy and made a diagnosis of CCE. Cilostazol and intravenous heparin improved the symptoms and decreased the creatinine level. We retrospectively studied the clinical features of 36 cases registered with a diagnosis of CCE in the Japanese literature.

Cholesterol crystal embolization: an atherosclerotic disease with frequent and varied cutaneous manifestations

In this paper the basic pathogenesis of cholesterol crystal embolization (CCE) is described, its clinical characteristics are presented and diagnosis and therapy are discussed. The main focus will be on the cutaneous manifestations; however, considering that CCE is a systemic illness, findings in other organs will also be highlighted, particularly the commonly involved renal and gastrointestinal systems.

Apheresis in the treatment of cholesterol embolic disease

Cholesterol embolic disease is a devastating complication of atherosclerosis. Universally recommended treatment is lacking thus far. Recent data suggest that a therapeutic protocol aimed at specifically combating three causes of mortality, recurrent bouts of cholesterol embolism, cardiac failure, and cahexia, were associated with a favorable clinical outcome. As for drug therapy, corticosteroid has been reported to be beneficial in reducing local and general inflammatory responses. Concerning apheresis, combined therapy consisting of plasma exchange and low to intermediate-dose corticosteroid therapy has been shown to be effective in multivisceral cholesterol embolism. Low density lipoprotein (LDL) apheresis has been reported to be beneficial for cholesterol embolism-induced damage to the skin and brain.

Pseudovasculitis: mechanisms of vascular injury and clinical spectrum

Pseudovasculitis, vasculitis-like syndromes, or mimics of vasculitis represent a heterogeneous collection of disorders that are capable of simulating a vasculitic disorder. Some conditions such as cardiac myxomas, cholesterol embolization, and fibromuscular dysplasia are more apt to cause confusion, but numerous other conditions can do so also. Inappropriate diagnosis leads to delay or absence of proper management and exposure to potentially deleterious treatment modalities such as corticosteroids and cytotoxic agents. The diagnosis of a pseudovasculitic disorder requires a high index of suspicion and should always be part of the differential diagnosis of vasculitis. The endothelium is thought to be pivotal in vascular injury; much has been learned using in vitro human umbilical vein endothelial cell cultures. Application of this knowledge to human disease and to vasculitic disorders and their imitators is still premature.

Cholesterol crystal embolization simulating focal myositis

Cholesterol crystal embolization usually produces characteristic skin lesions. We report a case responsible for myositis of the calf without suggestive skin lesions. The outcome in this 58-year-old patient was spontaneously favorable. Cholesterol crystal embolization can produce a range of clinical symptoms, with the skin, kidneys, and eyes being the most common targets. Generalized forms can result in systemic disease. The diagnosis rests on histological findings, and the treatment is symptomatic. Anticoagulants have been shown to worsen the manifestations, whereas antiplatelet therapy may be useful.

Cholesterol crystal embolism: A recognizable cause of renal disease

Cholesterol crystal embolism, sometimes separately designated atheroembolism, is an increasing and still underdiagnosed cause of renal dysfunction antemortem in elderly patients. Renal cholesterol crystal embolization, also known as atheroembolic renal disease, is caused by showers of cholesterol crystals from an atherosclerotic aorta that occlude small renal arteries. Although cholesterol crystal embolization can occur spontaneously, it is increasingly recognized as an iatrogenic complication from an invasive vascular procedure, such as manipulation of the aorta during angiography or vascular surgery, and after anticoagulant and fibrinolytic therapy. Cholesterol crystal embolism may give rise to different degrees of renal impairment. Some patients show only a moderate loss of renal function; in others, severe renal failure requiring dialysis ensues. An acute scenario with abrupt and sudden onset of renal failure may be observed. More frequently, a progressive loss of renal function occurs over weeks. A third clinical form of renal atheroemboli has been described, presenting as chronic, stable, and asymptomatic renal insufficiency. The renal outcome may be variable; some patients deteriorate or remain on dialysis, some improve, and some remain with chronic renal impairment. In addition to the kidneys, atheroembolization may involve the skin, gastrointestinal system, and central nervous system. Renal atheroembolic disease is a difficult and controversial diagnosis for the protean extrarenal manifestations of the disease. In the past, the diagnosis was often made postmortem. However, in the last decade, awareness of atheroembolic renal disease has improved, enabling us to make a correct premortem diagnosis in a number of patients. Correct diagnosis requires the clinician to be alert to the possibility. The typical patient is a white man aged older than 60 years with a baseline history of hypertension, smoking, and arterial disease. The presence of a classic triad characterized by a precipitating event, acute or subacute renal failure, and peripheral cholesterol crystal embolization strongly suggests the diagnosis. The confirmatory diagnosis can be made by means of biopsy of the target organs, including kidneys, skin, and the gastrointestinal system. Thus, Cinderella and her shoe now can be well matched during life. Patients with renal atheroemboli have a dismal outlook. A specific treatment is lacking. However, it is an important diagnosis to make because it may save the patient from inappropriate treatment. Finally, recent data suggest that an aggressive therapeutic approach with patient-tailored supportive measures may be associated with a favorable clinical outcome.

Thromboembolism in a patient with transient eosinophilia and thrombocytopenia

A 24-year-old woman with an unremarkable medical history who developed bilateral deep venous thrombosis and pulmonary emboli is presented. Associated findings were severe eosinophilia and moderate thrombocytopenia. Since the major acquired and hereditary thrombogenic disorders were ruled out in this case (including antiphospholipid syndrome and heparin-induced thrombocytopenia), we believe that the severe eosinophilia per se could be the pro-coagulant factor leading to thrombosis and embolism in our patient. The role of eosinophilia in thrombosis is discussed.

Do we really need to pay attention to the less common crystals?

In addition to monosodium urate, calcium pyrophosphate dihydrate, and apatite crystals, a wide variety of less common crystals, artifacts, and, occasionally, some unidentified birefringent materials may be seen in synovial fluids in association with acute or chronic arthritis. These unusual crystals and their associated musculoskeletal manifestations may be confused with the more common crystals and their manifestations and sometimes may provide the clue for systemic disease because they may present with a pseudovasculitis syndrome. Important advances in understanding the molecular aspect and management of primary hyperoxalurias as well as nephropathic cystinosis provide important general information to be applied in research and in the search for a more effective management of other common crystal-induced arthritis.