Presence Of Cholesterol Crystals Research Articles

A report on five cases of cholesterol granulomas in the thymus

BackgroundCholesterol granuloma (CG) is a benign entity characterized by the presence of cholesterol crystals and foreign body giant cells. This condition can be attributed to cholesterol crystals that are deposited in the tissues and react with foreign body giant cells, resulting in granuloma formation. Lesions commonly develop in the otolaryngeal region, such as the middle ear. However, crystals rarely form in the thymus, accounting for 1% of all mediastinal tumors. Herein, we present five cases of mediastinal CG.Case presentationThe patients were aged 49–61 (mean, 55.4) years. Among them, three were men and two women. One patient had fever, and four patients were asymptomatic. The patients’ lesions were detected during follow-up of other diseases or medical examinations showing the presence of abnormal chest shadows. The patients did not have a history of trauma or surgery. All lesions were located within the thymus gland. Three patients presented with multifocal lesions and two with a single lesion. Four patients had contrast effect on computed tomography scan. Four patients had abnormal fluorodeoxyglucose accumulation (mean maximum standardized uptake value, 4.67) on positron emission tomography-computed tomography. Four patients underwent complete surgical resection. The size of the resected lesions ranged from 1.8 to 5.1 (mean, 3.24) cm. Histologically, all patients presented with small nodules with cholesterol clefts and foreign body giant cells and histiocyte infiltration within the thymic tissue. The postoperative course was excellent. None of the patients who underwent complete resection presented with recurrence. Moreover, the patient who underwent partial resection did not have lesion enlargement.ConclusionsCG in the thymus is clinically challenging to differentiate from malignant lesions, and histologic diagnosis via surgical resection is required.

Cholesterol Crystals – A Beautiful Incidental Finding in Pleural Fluid

Chyliform (pseudochylous) pleural effusions build up over time as a result of the breakdown of cellular lipids in long-lasting pleural effusions such as those caused by tuberculosis and rheumatoid arthritis. Due to the high quantities of cholesterol in the pleural fluid and the presence of cholesterol crystals, these are also known as cholesterol effusions. We present the case report of a 62-year-old man who visited the outpatient pulmonary medicine clinic with a complaint of cough, hemoptysis, and shortness of breath. On radiological examination, a pleural effusion on the left side was found. A diagnosis of pseudochylous effusion was determined on the basis of the distinctive cytological features in the pleural fluid.

P62 SEASON VARIABILITY IN ATHEROSCLEROSIS COMPOSITION: INSIGHTS FROM 1848 NON–CULPRIT CORONARY PLAQUES

Abstract Background Several environmental and seasonal factors are thought to be crucial in the risk of acute coronary syndromes (ACS), including temperature, latitude, longitude, atmospheric air pressure, wind velocity and circadian period. However differences in coronary plaque composition according to season variation is still poorly understood. Purpose. Our study aims to analyse the characteristics of non–culprit coronary plaques in patients undergoing optical coherence tomography evaluation (OCT) evaluation of the left anterior descending artery. Methods We included 1848 non–culprit coronary plaques from 1003 patients of the CLIMA registry. The season of OCT pullback acquisition was collected for each patient. Results Overall, median age was 66 years (56–74), with 24.6% of women and 53.4% of ACS. At patient–level analysis, patients admitted in summer were less frequently affected by hypertension (59.8% vs 69.4% in autumn, 68.5% in winter and 72% in spring; p=0.027) and chronic kidney disease (14.8% vs 15.9% in autumn, 10.3% in winter and 19.4% in spring; p=0.037) in. At lesion–level analysis, similar values of fibrous cap thickness, maximum lipid arc, length of plaques and presence of macrophages were observed (Table 1). Summer plaques had a smaller minimum lumen area than spring plaques (5.7±3.1 vs 5.1±239; p=0.044) and also a less frequent superficial macrophage infiltration (23% vs 36.1% in autumn, 30.5% in winter and 30.6% in spring; p=0.030) and presence of cholesterol crystals (16.7% vs 23.8% in autumn, 28.4% in winter and 22.1% in spring; p=0.037 than three other season). Conclusions Coronary plaques during summer had less local sign of inflammation such superficial macrophage infiltration and cholesterol crystals. Further studies are needed to confirm these results and investigate clinical implications.

Clinical Images: Cholesterol crystals bursitis.

The patient, a 45-year-old woman, was referred to the outpatient clinic with an effusion of her right olecranon bursa. She had a history of systemic sclerosis, liver cirrhosis, and autoimmune hepatitis that was treated with mycophenolate mofetil and prednisone. About 3 years ago, she started to develop an effusion of the right olecranon bursa. More recently she noticed white skin nodules, which turned out to be calcinosis cutis. There were no signs of arthritis on either clinical examination or imaging. An ultrasound of the right olecranon bursa was performed and revealed a tissue mass with hyperechogenic lesions within, which is compatible with crystal depositions (A). Analysis of the aspirate with the polarization microscope indicated the presence of cholesterol crystals (B; left: original magnification × 40; right: original magnification × 10). These crystals usually look like plates of glass, sometimes with a notch out of a corner. They are variably and mildly birefringent. Under polarized light, they may exhibit a stained-glass effect. Most cases of cholesterol crystals are associated with hyperlipidemia, yet our patient had normal lipoprotein levels and did not use cholesterol-lowering medication. Instead, increased local cell degeneration and/or increased lipid permeability in response to chronic inflammation might have contributed to the formation of cholesterol crystals in the olecranon bursa of our patient. Cholesterol crystals have been described previously just once in a patient with scleroderma, in the subcutis, mimicking calcinosis cutis (1). After failing local corticosteroid injections, the patient was finally referred to the orthopedic surgeon for surgical synovectomy. Cholesterol crystals in bursal fluid of a patient with scleroderma has not been previously reported, as most of the cases reported so far in patients with rheumatic diseases are concerning patients with rheumatoid arthritis (2). Disclosure Form Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

42 SEASON VARIABILITY IN ATHEROSCLEROSIS COMPOSITION: INSIGHTS FROM 1848 NON-CULPRIT CORONARY PLQUES

Abstract Background Several environmental and seasonal factors are thought to be crucial in the risk of acute coronary syndromes (ACS), including temperature, latitude, longitude, atmospheric air pressure, wind velocity and circadian period. However differences in coronary plaque composition according to season variation is still poorly understood. Purpose Our study aims to analyse the characteristics of non-culprit coronary plaques in patients undergoing optical coherence tomography evaluation (OCT) evaluation of the left anterior descending artery. Methods We included 1848 non-culprit coronary plaques from 1003 patients of the CLIMA registry. The season of OCT pullback acquisition was collected for each patient. Results Overall, median age was 66 years (56-74), with 24.6% of women and 53.4% of ACS. At patient-level analysis, patients admitted in summer were less frequently affected by hypertension (59.8% vs 69.4% in autumn, 68.5% in winter and 72% in spring; p=0.027) and chronic kidney disease (14.8% vs 15.9% in autumn, 10.3% in winter and 19.4% in spring; p=0.037) in. At lesion-level analysis, similar values of fibrous cap thickness, maximum lipid arc, length of plaques and presence of macrophages were observed (Table 1). Summer plaques had a smaller minimum lumen area than spring plaques (5.7±3.1 vs 5.1±239; p=0.044) and also a less frequent superficial macrophage infiltration (23% vs 36.1% in autumn, 30.5% in winter and 30.6% in spring; p=0.030) and presence of cholesterol crystals (16.7% vs 23.8% in autumn, 28.4% in winter and 22.1% in spring; p=0.037 than three other season). Table 1 Conclusions Coronary plaques during summer had less local sign of inflammation such superficial macrophage infiltration and cholesterol crystals. Further studies are needed to confirm these results and investigate clinical implications.

Impact of small dense low-density lipoprotein cholesterol on cholesterol crystals in patients with acute coronary syndrome: An optical coherence tomography study

The presence of cholesterol crystals (CCs) is recognized as a component of vulnerable atherosclerotic plaques at risk of rupture. The phagocytosis of atherogenic lipid factors by macrophages precedes and promotes the formation of vulnerable plaques, but it is not clear how these factors affect the formation of CC. This study aimed to evaluate the relationship between lipid biomarkers such as small dense low-density lipoprotein cholesterol (sd-LDL-c) and CC detected by optical coherence tomography (OCT) in patients with acute coronary syndrome (ACS). Serum samples were collected immediately before coronary angiography in consecutive 174 patients with ACS who did not take statins and underwent OCT imaging of the culprit lesion. The sd-LDL-c levels were measured using a direct homogenous assay. CC was defined as a thin linear structure with high reflectivity and low signal attenuation on the OCT images. CC was identified in 85 patients (48.9%). The prevalence of CC was significantly higher in lesions with ruptured plaques and greater macrophage grade. The sd-LDL-c levels were significantly higher in the patients with CC (41.6 vs. 31.2 mg/dL, p=0.01) although there were no significant differences in the levels of LDL-c and apolipoprotein B. The CC group also had higher levels of apolipoprotein C3 and HbA1c levels. In multiple logistic regression analysis, sd-LDL-c was an independent risk factor of CC (odds ratio, 1.19 per 10 mg/dL; p=0.03). sd-LDL may play an important role in the presence of CC in patients with ACS.

Mopping up crystals to keep the blood flowing.

Despite substantial progress in the prevention and treatment of cardiovascular diseases, mortality and morbidity remain unacceptably high; stroke and myocardial infarction are still one of the biggest killers worldwide.1 One hallmark of a ruptured atherosclerotic plaque causing a clinical event is the presence of cholesterol crystals (CC) that are fuelled by high plasma cholesterol levels. These deposits are extremely pro-inflammatory which contributes to plaque inflammation, instability and rupture.

Low endothelial shear stress, microcalcification activity and high-risk plaque features: merging computational flow modelling, OCT and 18F-NaF PET/CT

Abstract Background Endothelial shear stress (ESS) has a critical role in endothelial function. Abnormal shear stress leads to endothelial dysfunction, which contributes to arterial plaque initiation and development. Four dimensional magnetic resonance can determine shear stress in the larger arteries but cannot resolve the detail needed to calculate shear stress in the coronary arteries and thus methods such as computational fluid dynamics (CFD) are required. Additionally, a key feature of biologically active plaques is microcalcification activity, and this can be detected using 18F-sodium fluoride (18F-NaF) positron emission tomography (PET). Furthermore, using high resolution optical coherence tomography (OCT), the high-risk features plaques can be visualized and quantified. We aimed to merge these three techniques to investigate if low ESS is associated with high-risk plaque features and active microcalcifications in acute coronary syndrome. Methods We began by merging OCT images with CTCA images to obtain detailed 3D reconstructions of the target vessel. We then simulated blood flow and calculated the ESS, from which we extracted the area of low ESS (<0.4 Pa). We quantified plaque features using OCT and measured the maximum 18F-NaF uptake, and compared data at both the coronary segment and whole artery level (Figure 1). Results We investigated 20 arteries from 18 patients which we obtained 38 coronary segments according to the SCCT guidelines. We found that areas of low ESS were were significantly and positively associated with high-risk plaque features: macrophage infiltration (segment, rs=0.33, p=0.043; artery, rs=0.46, p=0.041) and presence of cholesterol crystals (segment, rs=0.45, p=0.005; artery, rs=0.58, p=0.007). Vessel segments with thin-capped fibroatheroma had greater area of low ESS (20 vs 4%). The uptake of 18F-NaF was positively associated with the area of low ESS (segment, rs=0.52, p=0.001; artery, rs=0.64, p=0.002). We found that there were typically more plaque features found in regions of low ESS (Table 1). Conclusion Here we provide the first data associating low ESS with both high-risk plaque features and active microcalcifications in patients with acute coronary syndrome. Although our sample size is small, these data are encouraging and could lead to better understanding of how best to deem a plaque “high risk”. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Royal Perth Hospital Medical Research Foundation Figure 1Table 1

RELATIONSHIP BETWEEN THE PRESENCE OF CLEFTS OF CHOLESTEROL CRYSTALS IN PERIAPICAL LESIONS AND SERUM CHOLESTEROL LEVEL

Introduction: According to some studies, the source of cholesterol inside periapical lesions may be partially from the condensation and crystallization of cholesterol in the cyst wall. Further, the cholesterol can be derived from local metabolic products or the vascular circulation. Objective: This study aimed to analyze the relationship between the clefts of cholesterol crystals found in periapical lesions and cholesterol levels in the blood circulation. Study Design: An observational study of a descriptive nature that included 70 patients with periapical lesions (according to radiographic examination). These patients underwent extraction of the affected tooth unit and removal of the periapical lesion, which were then sent for pathologic examination. Further, the lipid profile and serum cholesterol level of the patients were assessed. Results: From all 70 participants, only 3 (4.3%) had clefts of cholesterol crystals that were present only in cysts (larger than 1.5 cm in diameter, approximately) and the rate of cholesterol serum levels in large and old injuries. Conclusion: The presence of cholesterol crystals is rare in periapical lesions. The study suggests a relationship between the presence of cholesterol crystals and the rate of cholesterol serum levels in large and old injuries.

Cholesterol Crystals in Embolic Debris are Associated with Postoperative Cerebral Embolism after Carotid Artery Stenting

Object: We investigated possible associations among the presence of cholesterol crystals in embolic debris, the proportions of debris components, and postoperative cerebral embolism in patients undergoing carotid artery stenting (CAS). Methods: Sixty-seven consecutive procedures were performed for internal carotid artery stenosis with CAS at our hospital between November 2015 and February 2018. Procedures for emergency CAS for stroke in evolution or crescendo transient ischemic attack were excluded (n = 12). The embolic debris from remaining procedures (n = 55) was stained with hematoxylin-eosin and the red blood cells, white blood cells, and fibrin were quantified by color-based segmentation. Cholesterol crystals and calcification were examined histopathologically. Diffusion-weighted imaging (DWI) was performed 1–3 days after CAS, and the images were used to classify procedures according to the presence of new lesions. Results: Of the 55 CAS procedures, new DWI lesions were identified after 32. One patient had symptomatic cerebral embolism. Higher proportions of patients with cholesterol crystals in embolic debris (17 vs. 78%, p < 0.001) and higher proportion of white blood cells (mean 2.3 [0–9.9] vs. 4.2% [0–29.9%], p < 0.01) were observed in the embolic debris of procedures with and without new DWI lesions. Conclusions: Cholesterol crystals were common in the embolic debris from patients with postoperative ischemic lesions after CAS. These results suggest that inflammatory destabilization of the intraplaque lipid component is related to postprocedural DWI lesions.

Cholesterol crystals in periapical lesions of root filled teeth.

To determine the prevalence of cholesterol crystals in periapical biopsies and to evaluate the correlation between cholesterol crystals in periapical biopsies and age, gender, location of the periapical lesion, pathologic diagnosis and lesion size. The biopsy report database (Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand) during 2005-2014 was reviewed. The prevalence of cholesterol crystals in the periapical lesions of root filled teeth was determined. Pathological diagnosis, patients' age, gender and the location (maxilla or mandible) of the periapical lesion were obtained from treatment records. The area of the lesion from the periapical radiograph before surgery was calculated using ImageJ software. Univariate and multivariate logistic regression analyses were used to determine the association between independent variables and the presence of cholesterol crystals. The overall prevalence of cholesterol crystals was 20.31%. The periapical biopsies >100mm2 in size on periapical films had a significantly greater prevalence of cholesterol crystals than those <100mm2 (P=0.005). The biopsies diagnosed as radicular cysts had a significantly greater prevalence of cholesterol crystals than the biopsies with other diagnoses (P<0.001). A pathological diagnosis of radicular cyst was the variable with the strongest association with the presence of cholesterol crystals (P<0.001; adjusted OR, 12.39). Presence of cholesterol crystals was associated with periapical lesion diagnosed as a radicular cyst and lesion >100mm2 in area. Age, gender and location of the lesion did not influence the presence of cholesterol crystals.

The signal intensity of coronary culprit lesions on T1-weighted magnetic resonance imaging is directly correlated with the accumulation of vulnerable morphologies

BackgroundIn the magnetic resonance T1-weighted imaging, some investigators have shown that coronary artery high-intensity signals (HISs) are associated with vulnerable plaque morphology and an increased risk of future cardiac events. Although previous studies used different PMR (the ratio between the signal intensities of coronary plaque and cardiac muscle) cutoff values to detect HIS, the association between PMR itself and plaque morphology has not been fully investigated. Methods and ResultsWe prospectively investigated the association between PMR values and plaque morphology detected by optical coherence tomography in consecutive 106 patients with angina pectoris. The lesions with almost all of the vulnerable features such as lipid-rich, thin-cap fibroatheroma, plaque rupture, thrombus, macrophage infiltrations, intimal vasculature, and absence of calcification had significantly higher PMR; the only exception was the presence of cholesterol crystals. PMR increases linearly with the number of vulnerable features (p<0.0001, Rho=0.504). Stepwise multiple linear regression analysis revealed that the absence of calcification (p=0.0027), and the presence of thrombus (p=0.0071) and intimal vasculature (p=0.019) were independently associated with higher log-transformed PMR. There was a stepwise increase in PMR of the culprit lesions in proportion to the accumulation of the number of adverse plaque characteristics defined as non-calcified plaque, thrombus, and/or intimal vasculature. ConclusionThese results suggest that not only the presence of HIS, but also the elevated PMR itself may be used as a quantitative marker of plaque vulnerability in clinical evaluation.

Characteristics of patients with pseudochylothorax-a systematic review.

Pseudochylothorax (PCT) (cholesterol pleurisy or chyliform effusion) is a cholesterol-rich pleural effusion (PE) that is commonly associated with chronic inflammatory disorders. Nevertheless, the characteristics of patients with PCT are poorly defined. A systematic review was performed across two electronic databases searching for studies reporting clinical findings, PE characteristics, and the most effective treatment of PCT. Case descriptions and retrospective studies were included. The review consisted of 62 studies with a total of 104 patients. Median age was 58 years, the male/female ratio was 2.6/1, and in the 88.5% of cases the etiology was tuberculosis (TB) or rheumatoid arthritis (RA). PE was usually unilateral (88%) and occupied greater than one-third of the hemithorax (96.3%). There was no evidence of pleural thickening in 20.6% of patients, and 14 patients had a previous PE. The pleural fluid (PF) was an exudate, usually milky (94%) and with a predominance of lymphocytes (61.1%). The most sensitive tests to establish the diagnosis were the cholesterol/triglycerides ratio (CHOL/TG ratio) >1, and the presence of cholesterol crystals (97.4% and 89.7%, respectively). PF culture for TB was positive in the 34.1% of patients. Favorable outcomes with medical treatment, therapeutic thoracentesis, decortication/pleurectomy, pleurodesis, thoracic drainage and thoracoscopic drainage were achieved in 78.9%, 47.8%, 86.7%, 66.6%, 37.5% and 42.9%, respectively. PCT is usually tuberculous or rheumatoid, unilateral and the PF is a milky exudate. The presence of cholesterol crystals and a CHOL/TG ratio >1 are the most sensitive test for the diagnosis. The lack of pleural thickening does not rule out PCT. Treatment should be sequential, treating the underlying causes, and assessing the need for interventional techniques.

Percutaneous coronary interventions in the diabetic patient: where do we stand?

Clinical observations made during the past 20 years have suggested that patients with diabetes mellitus (DM) have suboptimal outcomes after percutaneous coronary interventions (PCIs).1–4 During the same time period, mechanistic studies have provided insights into the cardiovascular risk of DM. In this report, we attempt to synthesize observations made in the experimental laboratory with those made in the clinical setting to identify how diabetic traits may compromise the success of PCI (Figure 1). Figure 1. Diabetic traits potentially compromising the success of percutaneous coronary intervention. The hallmarks of DM are hyperglycemia, insulin resistance or an absolute lack of endogenous insulin, and hyperinsulinemia. These metabolic derangements may lead to premature atherosclerosis, cardiomyocyte dysfunction, and renal failure through several mechanisms. ### Diabetic Arteriopathy In an early stage of atherogenesis, the presence of cholesterol crystals may induce the formation of small hydroxyapatite mineral clefts, which are also called microcalcifications, in the intima or media.5 In DM, medial calcification develops independently of hypercholesterolemia and may cause sheet-like calcific deposits that reduce vascular compliance.6 In the presence of hyperglycemia, medial calcification may be mediated by a glycosylation process, in which N-acetylglucosamine (O-GlcNAc) binds to serine and threonine residues of vascular proteins.7 In a drug-induced mouse model of type 1 DM, Heath et al6 found a strong increase in vascular O-GlcNAcylation after the onset of increased blood glucose levels, along with a significant increase in aortic calcium content and vascular stiffness. The connection between O-GlcNAcylation and the development of a mineralized matrix was confirmed in an experimental model of vascular smooth muscle cells cultured in osteogenic differentiation media along with an inhibitor of N-acetylglucosaminidase.6 The formation of vulnerable atherosclerotic lesions may be related to hyperglycemia8 or insulin resistance.9 Kuroda et al8 observed that daily glucose fluctuations, measured as the …

Feasibility of the assessment of cholesterol crystals in human macrophages using micro optical coherence tomography.

The presence of cholesterol crystals is a hallmark of atherosclerosis, but until recently, such crystals have been considered to be passive components of necrotic plaque cores. Recent studies have demonstrated that phagocytosis of cholesterol crystals by macrophages may actively precipitate plaque progression via an inflammatory pathway, emphasizing the need for methods to study the interaction between macrophages and crystalline cholesterol. In this study, we demonstrate the feasibility of detecting cholesterol in macrophages in situ using Micro-Optical Coherence Tomography (µOCT), an imaging modality we have recently developed with 1-µm resolution. Macrophages containing cholesterol crystals frequently demonstrated highly scattering constituents in their cytoplasm on µOCT imaging, and µOCT was able to evaluate cholesterol crystals in cultured macrophage cells. Our results suggest that µOCT may be useful for the detection and characterization of inflammatory activity associated with cholesterol crystals in the coronary artery.

Cholesterol Granuloma of the Maxillary Sinüs: A Case Report

Cholesterol granuloma is a description of the reaction of different tissues to the presence of cholesterol crystals. It can be found in several areas of the body, including middle ear, mastoid process, breast, sella turcica, pontocerebelline angle, testis, lungs, brain, and kidneys, and in the apex of the temporal bone pyramid. Maxillary sinus localization is rare. A 24-yearold woman presented with symptoms of nasal obstruction and headache. Computed tomography scan of the paranasal sinuses showed a lesion of soft tissue density occupying the right maxillary sinus. The lesion, localized in the right maxillary antrum, was excised. Histopathological examination revealed an intact mucosa with a large number of submucosal cholesterol clefts surrounded by foreign body granulation tissue. These findings led us to the diagnosis of cholesterol granuloma. Cholesterol granuloma should be considered in the differential diagnosis of sinus lesions. Complete excision would provide a good prognosis.

Surgical treatment of recurrent pseudochylothorax occurring after therapy of tuberculous pleurisy

Pseudochylothorax is an uncommon pleural effusion disease characterized by the presence of cholesterol crystals or high lipid content not resulting from a disrupted thoracic duct. Most of the cases reported so far had been found in patients with long-standing pleural effusion due to a chronic inflammatory disease such as old tuberculous pleurisy or chronic rheumatoid pleurisy. Authors encountered a case of pseudochylothorax in a 45-year-old man who had been treated for tuberculous pleurisy 6 years before his visit to authors’ hospital. After that, he had visited the emergency department many times for removal of pleural effusion. The patient’s chest X-ray revealed dyspnea and large left-sided pleural effusion. Although a large amount of pleural fluid was removed with a drainage catheter, massive pleural effusion was likely to recur, and the underlying lung was able to fully re-expand. Accordingly, decortication was done, and the patient’s symptom was improved without postoperative complications.

English

Thyroid lesions are found in 3-7% of population worldwide. The overwhelming majority of thyroid nodules are benign in nature. Thyroid cancers are rare; however thyroid carcinoma is the most common malignancy involving the endocrine glands and is responsible for approximately 1.5% of new cancer cases annually. The clinical challenge is to distinguish the few clinically significant malignant nodules from the many benign nodules because malignant thyroid lesions shows good long term prognosis after surgical excision. Aims : To Assess the sensitivity and specificity of sonographic findings in differentiation of benign and malignant thyroid lesion. Method: A hospital based prospective study was done on 100 patients with palpable thyroid nodules using high resolution ultrasonography and findings correlated with fine needle aspiration cytology. Result: Sensitivity and Specificity of sonography to differentiate benign and malignant thyroid lesions (FNAC correlation) was 70.59 % & 96.39 % respectively. Presence of non shadowing echogenic cholesterol crystals showed high sensitivity of 58.70 % and specificity of 83.33 % for benign thyroid nodules. Sensitivity and Specificity of absence of thin peripheral halo around malignant lesions were 70.4 % & 65.8% respectively. Sensitivity and Specificity of hypoechogenicity for malignant lesions were 64.71 % and 98.80 %.Presence of fine calcification was showing high Sensitivity & Specificity of 64.71 % and 93.98 % respectively in malignant lesions. Predominant intra-nodular colour flow pattern in solid nodules was predictive of malignancy with Sensitivity 82.35 and Specificity 84.34 %. Higher RI value (greater than 0.77) were significantly found in malignant lesions with sensitivity of 78.57 % and specificity of 92.31%. Solid and predominantly solid lesions show high Sensitivity, Specificity for being a malignant lesion 70.59 % & 55.42 respectively but less Positive Predictive Value of24.49 %. Conclusion: Sonographic characteristics of marked hypoechoic echotexture, solid and predominantly solid nature, absence of peripheral halo, presence of cholesterol crystals, fine calcification, and internal vascularity with high resistive index show high diagnostic accuracy to differentiate benign and malignant lesions.

Original article Circulated CD4 + CD28 - lymphocytes rate and their cytotoxicity and morphological parameters of internal carotid artery atheromatous plaques in patients with atherosclerosis-related ischemic stroke

The question about the role of CD4+CD28- lymphocytes in the pathogenesis of atherosclerosis-related ischemic stroke is still open. The study included patients, who underwent endarterectomy of internal carotid arteries. The group consisted of patients after stroke and ones without previous stroke. The histopathologic examination of obtained plaques has been performed. The percentage of CD4+CD28- lymphocytes in peripheral blood and their cytotoxicity has been assessed for each patient. The global percentage of CD4+CD28- lymphocytes in blood was higher in the group of patients with plaques where connective tissue fibers consisted significantly of collagen fibers. The cytotoxicity of analysed cells related to less plaques calcification and presence of cholesterol crystals in the plaque. A multifactor regression of dependent variable presented the last relationship above as a only strong. CD4+CD28- cytotoxic lymphocytes seem to be involved in carotid atherosclerotic plaques development. Intraplaque cholesterol deposits may contribute to this process.

Massive Pericardial Effusion with Cardiac Tamponade Secundary to Cholesterol Pericarditis

The presence of cholesterol crystals in the pericardial fluid is a very rare finding of unknown pathogenesis with no more than 100 reported cases in literature. Patients with cholesterol pericarditis usually have large volume spills of slow development that are well tolerated, rarely causing cardiac tamponade or constrictive pericarditis. We report a case of cholesterol pericarditis with a severe pericardial effusion and cardiac tamponade in a patient with an uncertain diagnosis of tuberculosis.