Cholesterol embolisation after thrombolytic therapy

Cholesterol Embolization Syndrome After Kidney Transplantation: A Case Series and Systematic Review

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Background.

Cholesterol embolization syndrome (CES) is an uncommon but well-known cause of renal failure in native kidneys, but little is known about CES in kidney transplant recipients. The aim of this study was to determine the incidence, clinical characteristics, histopathology, and prognosis of CES after kidney transplantation.

Methods.

CES cases in both transplanted and native kidneys (control group) were identified by searching the databases of the divisions of Nephrology and Pathology of our institution. Clinical data were retrospectively collected. Biopsies were classified according to the latest Banff 2019 Update. Second, a systematic literature search was performed (December 01, 2020) of Ovid MEDLINE, EMBASE, the Cochrane Central Register of controlled trials, Google Scholar, and Web of Science.

Results.

CES was observed in for-cause biopsies of 11 out of 2350 (0.47%) kidney transplant recipients transplanted between January 1, 2006, and December 31, 2018 (0.0009 cases per person-year). All patients had ≥1 cardiovascular risk factor, and 9 donors were expanded criteria donors. Graft loss occurred in 27.3% of the patients diagnosed with CES. Eight transplant biopsies with CES were also classified as biopsy-proven acute rejection. Transplant biopsies showed signs of inflammation (arteritis, n = 7; interstitial inflammation, n = 5; tubulitis, n = 7). One patient with CES in a native kidney was identified. The biopsy of the native kidney only showed arteritis and classified as an isolated “v” lesion. The literature search resulted in 188 unique articles of which 20 were included. A total of 47 cases of CES after kidney transplantation was reported. Cholesterol emboli were found in <1% of all kidney transplant biopsies. In 57.8% of the kidney transplant biopsies with CES described in literature, concomitant inflammation was present.

Conclusions.

CES is an uncommon cause of kidney transplant failure, although the incidence of CES may be underestimated. CES may mimic rejection as it can be accompanied by arteritis.

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.

Lack of association between dialysis modality and outcomes in atheroembolic renal disease

BACKGROUND AND OBJECTIVES

Atheroembolic renal disease (AERD) can require dialytic support. Because anticoagulation may trigger atheroembolization, peritoneal dialysis may be preferred to hemodialysis. However, the effect of dialysis modality on renal and patient outcomes in AERD is unknown.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

A subcohort of 111 subjects who developed acute/subacute renal failure requiring dialysis was identified from a larger longitudinal study of AERD. The main exposure of interest was dialysis modality (peritoneal versus extracorporeal therapies). Logistic regression was used to study the probability of renal function recovery. Times from dialysis initiation to death were studied using Cox's regression.

RESULTS

Eighty-six patients received hemodialysis and 25 received peritoneal dialysis. The probability of renal function recovery was similar by dialysis modality (25% among hemodialysis patients and 24% among peritoneal dialysis patients; P = 0.873). During follow-up, 58 patients died, 14 among peritoneal patients and 44 among hemodialysis patients (P = 0.705). In multivariable analysis, gastrointestinal tract involvement and use of statins maintained an independent effect on the risk of patient death.

CONCLUSIONS

This study does not support the notion that one dialysis modality is superior to the other. However, the observational nature of the data precludes any firm conclusions.

Cholesterol embolization syndrome induced by thrombolytic therapy

Cholesterol embolization syndrome (CES) induced by thrombolytic therapy is a rare syndrome with a high incidence of morbidity and mortality. The variability in clinical presentations may cause a delay in diagnosis of CES. This article presents a comprehensive review of the English literature from January 1980 to December 2007 identifying all published case reports of CES induced by thrombolytic therapy. Multiple electronic databases were searched and relevant reference lists were hand searched to identify all case reports. Thirty cases of thrombolytic-induced CES were identified. Indications for thrombolysis were acute myocardial infarction (28 patients) and deep venous thrombosis (two patients). Skin and renal involvement were the most common presentations. Skin manifestations included livedo reticularis, rash, and skin mottling. Other clinical symptoms included cyanotic toes, gastrointestinal bleeding, or perforation, myalgias, retinal emboli, and CNS involvement. Morbidity and mortality were high. Outcomes included chronic hemodialysis in eight patients, four patients underwent amputations, seven patients developed or had progression of their chronic kidney disease, and seven deaths occurred.CES presents as multiorgan dysfunction and should be considered in the differential diagnosis of the symptom complex that may develop after thrombolytic therapy. Diagnosis of CES can be difficult as a result of the variable clinical presentations. A thorough clinical history and physical examination are essential first steps in establishing a diagnosis. Confirmatory diagnosis requires biopsy of the target organs. Measures to reduce the likelihood of recurrence should be taken and include avoidance of anticoagulation therapy and vascular procedures. Unfortunately, therapy remains supportive and the outcome is invariably poor.

Livedo reticularis: An update

Livedo reticularis (LR) is a well-known, relatively common physical finding consisting of macular, violaceous, connecting rings that form a netlike pattern (Fig 1). In most cases, it is a completely benign finding related to cold exposure. However, there are many potential causes (Table I), and this can make the evaluation of a patient presenting with this finding very difficult. An excellent review of the topic by Fleischer and Resnick was published in 1990. We have endeavored to update the literature and provide clinicians with guidance regarding the evaluation and treatment of patients presenting with LR.

Livedo Reticularis: An Underutilized Diagnostic Clue in Cholesterol Embolization Syndrome

BACKGROUND

Cholesterol embolization syndrome (CES) is an increasingly recognized cause of acute renal insufficiency, which must be differentiated from other forms of systemic vasculitis by histologic examination of biopsies from involved organs. This report describes the optimal methods for detection and biopsy of areas of skin involved with livedo reticularis to confirm the diagnosis of CES.

METHODS

This report describes 8 patients with unexplained acute renal insufficiency in whom the diagnosis of CES was suspected based on their clinical history.

RESULTS

A detailed skin examination performed in both supine and upright postures demonstrated the presence of previously unrecognized livedo reticularis, which was more evident during upright posture in all subjects. In 2 subjects, questionable areas of livedo reticularis noted in supine posture became readily demonstrable during upright posture. Livedo reticularis was apparent only during upright posture in 2 subjects. Biopsies of areas of skin involved with livedo reticularis demonstrated cholesterol emboli in 6 of 8 patients and were normal in the remaining 2 patients. One patient progressed to end-stage renal disease and one was lost to follow-up. In the remaining 6 patients, renal insufficiency initially progressed but did not require dialytic therapy. Renal function returned to baseline levels and livedo reticularis resolved without recurrence in these patients. No subjects developed clinical or laboratory evidence of systemic vasculitis.

CONCLUSIONS

Livedo reticularis is a common but often unrecognized finding in CES that may not be evident during routine examination performed in the supine posture. Deep cutaneous biopsy of areas of livedo reticularis can be safely used to confirm the presence of cholesterol emboli, thus avoiding the increased morbidity of biopsy of either pregangrenous skin lesions or visceral organs. Many patients with CES regain renal function during long-term follow-up.

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.

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.