D-二聚体与肺泡-动脉氧分压差测定在肺栓塞诊断中的应用

目的探讨D-二聚体(D-dimer, DD)与肺泡-动脉氧分压差(A-aDO2)测定在肺栓塞诊断中的应用价值.方法采用法国AST-compact血凝分析仪与丹麦Radiometer-ABL 520血气分析仪测定患者血浆中DD与A-aDO2指标,并对肺栓塞可疑患者与对照组进行两指标测定.结果共有86例患者与30例对照者进行检测,有28例患者(32.5%)的DD检测值<500 ng/ml,58例(67.5%)的DD检测值>500 ng/ml;有36例患者(41.8%)的A-aDO2检测值<2.6 kPa,50例患者(58.2%)的A-aDO2>2.6 kPa;86例患者组中有12例经肺通气-灌注扫描证实为肺栓塞.DD与A-aDO2联合检测诊断肺栓塞灵敏度为100%,阴性预测值为100%.结论 DD与A-aDO2联合检测可作为排除诊断肺栓塞的首选筛选试验.     

D-二聚体与肺泡-动脉氧分压差测定在肺栓塞诊断中的应用

目的　探讨D 二聚体 (D dimer,DD)与肺泡 动脉氧分压差 (A aDO2 )测定在肺栓塞诊断中的应用价值。方法　采用法国AST compact血凝分析仪与丹麦Radiometer ABL 5 2 0血气分析仪测定患者血浆中DD与A aDO2 指标 ,并对肺栓塞可疑患者与对照组进行两指标测定。结果　共有 86例患者与 30例对照者进行检测 ,有 2 8例患者 (32 .5 % )的DD检测值 <5 0 0ng/ml,5 8例 (6 7.5 % )的DD检测值 >5 0 0ng/ml;有 36例患者 (41.8% )的A aDO2 检测值 <2 .6kPa ,5 0例患者 (5 8.2 % )的A aDO2 >2 .6kPa ;86例患者组中有 12例经肺通气 灌注扫描证实为肺栓塞。DD与A aDO2 联合检测诊断肺栓塞灵敏度为 10 0 % ,阴性预测值为 10 0 %。结论　DD与A aDO2 联合检测可作为排除诊断肺栓塞的首选筛选试验。     

血浆D-二聚体含量测定在诊断继发性纤溶疾病中的意义

目的：通过对各种肿瘤、胶原病及肾病患者血浆D－二聚体水平的检测。证实体内继发纤溶的发生，从而为临床提供预防早期弥散性血管内凝血（DIC）发生的实验室依据。方法：采用乳胶凝集法（半定量法）。结果：白血病及各种实体瘤患者血浆D－二聚体含量显著增高，系统性红斑狼疮（SLE）及各种肾炎患者不仅血浆中D－二聚体含量增高，而且尿中也增高。结论：D－二聚体测定可作为临床DIC发生的早期实验室诊断依据。     

D-二聚体测定在肺栓塞诊断中的应用价值

近年来随着生活水平的提高和生活方式的改变 ,我国的肺栓塞发病率也呈现逐年升高趋势 ,其病死率仅次于心肌梗塞和肿瘤。及时准确诊断为肺栓塞者 ,其死亡仅为 7% ,反之其死亡率为 6 0 % ,其中 33%在发病后第 1小时内死亡。所以早期诊断肺栓塞是临床医生极为关注的问题。[1] 用全自动免疫系统 (VIDAS)DD法检测D 二聚体在诊断肺栓塞中有一定的应用价值。现将本实验的情况报道如下 :1　材料和方法1.1　材料1.1.1　对象选择 2 0 0 1年 11月～ 2 0 0 3年 1月可疑肺栓塞患者 98例 ,其中男 5 8例 ,女 4 0例 ,患者平均年龄为 5 9岁 (范围为 2 0～…     

血浆纤维蛋白原测定及D—二聚体检测在妊高征中的意义

目的：探讨妊高征患者血浆纤维蛋白原在D－二聚体的变化及临床意义。方法：以24例妊高征者（妊高征组，其中重度妊高征15例，轻、中度妊高征9例），和正常妊娠妇女20例（对照组）为观察，采用PT导出纤维蛋白原测定法（PT－der法）定量检测血浆纤维蛋白原；采用乳胶凝集法半定量测定血浆D－二聚体。结果：重度妊高征患者血浆纤维蛋白原水平和D－二聚体检测阳性率明显增高（P＜0．05），但轻、中度妊高征患者与正常妊娠妇女间差异无显著性。结论：血浆纤维蛋白原水平和D－二聚体检测阳性率在妊高征患者明显升高，并与疾病严重程度相一致。     

血浆降钙素原与D-二聚体水平在判断急性胆管炎病情严重程度中的临床价值

目的探讨急性胆管炎患者血浆降钙素原(PCT)及D二聚体(DD)水平在判断病情严重程度方面的临床价值。方法回顾性收集2018年1月至2019年2月首都医科大学附属北京友谊医院收治的113例急性胆管炎患者,在初次就诊时进行血浆PCT及DD检测。根据急性胆管炎的严重程度将患者分为三组:轻度急性胆管炎48例(42. 48%),中度急性胆管炎42例(37. 17%),重度急性胆管炎23例(20. 35%)。比较三组患者PCT、DD水平与胆管炎严重程度的相关性。结果 PCT和DD与急性胆管炎患者的严重程度分级相关,PCT的相关系数为0. 667,DD的相关系数为0. 692,重度急性胆管炎患者的PCT及DD水平均高于中度急性胆管炎患者(11. 97 ng/ml vs. 3. 84 ng/ml,11. 87mg/L vs. 3. 54 mg/L,P=0. 000,P=0. 000)及轻度急性胆管炎患者(11. 97 ng/ml vs. 1. 09 ng/ml,11. 87 mg/L vs. 1. 65mg/L,P=0. 000,P=0. 000),PCT诊断重度急性胆管炎的临界值为3. 72 ng/ml(敏感性为87%,特异性为81%),DD诊断重度急性胆管炎的临界值为3. 50 mg/L(敏感性为87%,特异性为79%)。结论血浆PCT及DD水平可作为预测重度急性胆管炎的指标,因此,两者可作为紧急胆道减压的辅助生物标记物。     

肾病综合征患者血浆D—二聚体检测的临床意义

为了探讨肾病综合征（NS）血栓形成及溶解情况，采用ELISA双抗体夹心法对121例NS患者检测血浆D－二聚体（D-dimer）含量。结果表明，初诊为NS的患者其血中含量为2．27±094（mg／L），明显高于正常对照组（P＜0．001），阳性率为94．2％；经治疗缓解后D－二聚体含量明显下降。提示NS患者临床上虽无明显的血栓形成的症状，但绝大多数患者体内有微血栓形成；血浆D－二聚体检测是判断NS患者高凝、血栓形成、血栓溶解等情况一个较好的指标。     

超声、多层螺旋CT及血浆D-二聚体在重症肺栓塞中的诊断价值

目的:探讨超声、多层螺旋CT成像技术及血浆D-二聚体(DD)浓度检测在重症肺栓塞中的诊断价值.方法:随机抽选广东医科大学附属第三医院2018年9月-2020年5月收治的接受超声、多层螺旋CT成像技术及血浆DD浓度检测的重症肺栓塞57例患者的临床资料,以CT造影检查为金标准,比较超声检查、血浆DD浓度检测及超声联合DD检...     

血浆D—二聚体含量与脑卒中类型、病期的相关性研究

目的：探讨血浆D－二聚3体与脑卒中类型及病期之间的关系。方法：运用乳胶颗粒法对354例脑卒中患者的血浆D－二聚体含量进行检测,并与正常对照组比较,结果：脑卒中急性期和恢复期患者的血浆D－二聚体含量均显著高于正常对照组（P＜0．01）,脑梗死恢复期患者的血浆D－二聚体含量显著低于急性期患者（P＜0．05）。结论：脑卒中患者存在高凝状态和纤溶功能亢进,血浆D－二聚体含量可作为观察其病情演变,判断其聚后的指标。     

血浆D-二聚体在鉴别大面积肺栓塞与非大面积肺栓塞中的价值

目的 探讨肺栓塞(PE)患者血浆D二聚体变化规律及在鉴别大面积肺栓塞与非大面积肺栓塞中的价值.方法 入选研究对象84例,均经CTPA确诊为肺栓塞,探讨其血浆D-聚体结果及变化规律.结果 54例患者D-二聚体高于500 ng/ml(64.3％),大面积、次大面积PE患者D二聚体明显高于非大面积组.结论 血浆D-二聚体仍作为诊断和鉴别诊断PE的首要手段之一,对鉴别大面积肺栓塞与非大面积肺栓塞有重要价值.     

Laboratory diagnosis of pulmonary embolism: value of increased levels of plasma D-dimer and thrombin--antithrombin III complexes

Plasma D-dimer (DD) and thrombin--antithrombin III complex (TAT) were measured with ELISAs in 99 patients investigated by 102 ventilation--perfusion lung scintigraphy because of suspected pulmonary embolism. High-probability lung scan was associated with increased DD (more than 500 ng/ml) and TAT (more than 4.1 ng/ml) levels (sensitivity of 100 and 70%, respectively). The corresponding figures of specificity were 81 and 42%. In the 56 patients with low-probability or indeterminate probability scans, 31 (55%) had DD concentrations of less than 500 ng/ml. These preliminary data suggest that a plasma DD concentration of less than 500 ng/ml might rule out the diagnosis of pulmonary embolism in suspected patients with an inconclusive lung scanning.     

The predictive characteristics of D-dimer testing in outpatients with suspected venous thromboembolism: a Bayesian approach

BACKGROUND: Despite the widespread use of quantitative methods to measure D-dimer, clinical decisions commonly are based only on binary test information (positive/negative). This study aimed to determine the significance of quantitative D-dimer results in the evaluation of venous thromboembolism (VTE) by means of a differentiated Bayesian approach. METHODS: Prospective study in 118 outpatients referred for workup of suspected pulmonary embolism (n = 75) or deep vein thrombosis (n = 43). The sensitivity and specificity of D-dimer results obtained by DD VIDAS (Biomerieux, France), STA Liatest (Diagnostica Stago, France), and D-dimer plus (Dade, US) were assessed for five different cut-offs. Further, predictive values and multilevel likelihood ratios were calculated in order to assess the operative test characteristics in excluding or confirming VTE. RESULTS: At a cut-off of 500 ng/ml and pretest probabilities < 47%, the VIDAS provides a negative predictive value (NPV) > 95%, whereas a positive predictive value (PPV) > 95% is obtained in patients with a D-dimer > 10,000 ng/ml and pretest probabilities > 50%. At a cut-off of 500 ng/ml and pretest probabilities < 33%, the Liatest exhibits a NPV > 95%, whereas a PPV > 95% is obtained in patients with a D-dimer >10,000 ng/ml and pretest probabilities > 37%. Finally, with the D-dimer plus, a NPV > 95% is seen at a cut-off of 150 ng/ml and pretest probabilities < 30%, whereas a PPV > 95% is obtained at a cut-off > 1000 ng/ml and pretest probabilities > 67%. CONCLUSIONS: D-dimer measurements in outpatients cannot only allow for exclusion but, in some situations, also for confirmation of venous thromboembolism. It is therefore advisable to conduct a quantitative interpretation of D-dimer results.     

血浆D-二聚体在肺栓塞患者中的诊断意义

目的:探讨快速定量检测D-二聚体在诊断肺栓塞患者中的临床价值。方法:检测、分析21例经螺旋CT或肺动脉造影确诊的肺栓塞患者及19例健康人(对照组)的血浆D-二聚体含量。结果:与对照组比较,肺栓塞组D-二聚体含量明显升高,有显著性差异(P<0.01)。结论:肺栓塞患者D-二聚体含量明显升高,敏感性为100%,阴性预测值为100%,检测D-二聚体可作为诊断肺栓塞的首选筛选试验。     

Clinical effects of antiplatelet drugs and statins on D‐dimer levels

Background

Acute pulmonary embolism may be ruled out by combining nonhigh clinical probability and a normal D‐dimer level. Both antiplatelet drugs and HMG‐CoA reductase inhibitors (statins) have been associated with effects on thrombus formation, potentially influencing D‐dimer levels in this setting, leading to a higher rate of false‐negative tests. Therefore, we determined whether D‐dimer levels in patients with suspected pulmonary embolism are affected by concomitant use of antiplatelet drugs and/or statins and evaluated whether the effect of antiplatelet drugs or statins might affect diagnostic accuracy.

Materials and methods

We performed a posthoc analysis in the YEARS diagnostic study, comparing age‐ and sex‐adjusted D‐dimer levels among users of antiplatelet drugs, statins and nonusers. We then reclassified patients within the YEARS algorithm by developing a model in which we adjusted D‐dimer cut‐offs for statin use and evaluated diagnostic accuracy.

Results

We included 156 statins users, 147 antiplatelet drugs users and 726 nonusers of either drugs, all with suspected pulmonary embolism . Use of antiplatelet drugs did not have a significant effect, whereas statin use was associated with 15% decrease in D‐dimer levels (95% CI, ?28% to ?0.6%). An algorithm with lower D‐dimer thresholds in statin users yielded lower specificity (0.42 compared to 0.33) with no difference in false‐negative tests.

Conclusions

We conclude that use of statins but not of antiplatelet agents is associated with a modest decrease in D‐dimer levels. Adjusting D‐dimer cut‐offs for statin use did, however, not result in a safer diagnostic strategy in our cohort.

     

Accuracy of d-dimer/fibrinogen ratio to predict pulmonary embolism: a prospective diagnostic study

Summary. d ‐Dimer and fibrinogen are elevated in many diseases presenting signs and symptoms similar to those seen in patients with pulmonary embolism (PE). We tested the hypothesis that patients with PE have lower fibrinogen and higher d ‐dimer values than patients in whom the diagnosis is suspected but safely excluded. One hundred and ninety‐one consecutive patients with suspected acute PE (85 positive, 106 negative) were investigated with a diagnostic strategy including d ‐dimer, pretest probability, and helical computed tomography as first‐line tests. In 38 of 40 patients with suspected PE and d ‐dimer <500 µg L^?1, PE was excluded without further testing. During a 3‐month follow‐up, there was no clinical PE among these 38 and the 68 patients with a negative helical CT. In 151 patients with d ‐dimer >500 µg L^?1, d ‐dimer, fibrinogen, and d ‐dimer/fibrinogen ratio (D/F ratio) were different in PE‐positive compared with PE‐negative patients [medians (and ranges) for d ‐dimer: 3793 (780 – 42 195) vs. 992 (621–6957) µg L^?1, fibrinogen: 3.8 (0.4–6.2) vs. 4.7 (2.2–8.4) g L^?1, and D/F ratio: 1.22 (0.15–85.45) 10³ vs. 0.25 (0.09–1.03) × 10³; P < 0.0001, respectively). The true positive rate was almost twice as high using D/F ratio >1.04 × 10³ (49 of 85 patients; 57.6%) compared with d ‐dimer >7000 µg L^?1 (25 of 85 patients; 29.4%). Patients with acute PE have lower fibrinogen values than patients with suspected but excluded PE. D/F ratio >10³ is highly specific for the presence of acute PE, and causes a doubling of the diagnostic rate compared with d ‐dimer testing alone.     

Reducing the use of diagnostic imaging in patients with suspected pulmonary embolism: validation of a risk assessment strategy

Objectives: The aims of this study were to measure the: (i) effects of implementation of a new risk assessment strategy for patients with suspected pulmonary embolism (PE) on the use of imaging and D‐dimer assay; (ii) negative predictive value for PE of a combination of low risk and negative D‐dimer assay; and (iii) compliance of ED clinicians with the strategy. Methods: A non‐randomized clinical trial was conducted in the ED of a 720‐bed teaching hospital between November 2002 and August 2003. Study subjects with suspected PE were compared with 191 randomly selected historical controls. The risk assessment strategy of Kline et al. was disseminated and implemented. Results: The negative predictive value for PE was 99% (95% confidence interval [CI] = 97–100%) in 114 patients with low risk and negative D‐dimer. There was a 21% absolute reduction in the rate of imaging following the implementation of the risk assessment strategy (56% vs 77%, P < 0.001). Conclusion: Low risk combined with a negative D‐dimer result may allow exclusion of PE without imaging.     

D‐dimer threshold increase with pretest probability unlikely for pulmonary embolism to decrease unnecessary computerized tomographic pulmonary angiography

Summary. Background: Increasing the threshold to define a positive D‐dimer could reduce unnecessary computed tomographic pulmonary angiography (CTPA) for a suspected pulmonary embolism (PE) but might increase rates of a missed PE and missed pneumonia, the most common non‐thromboembolic diagnosis seen on CTPA. Objective: Measure the effect of doubling the standard D‐dimer threshold for ‘PE unlikely’ Revised Geneva (RGS) or Wells’ scores on the exclusion rate, frequency and size of a missed PE and missed pneumonia. Methods: Patients evaluated for a suspected PE with 64‐channel CTPA were prospectively enrolled from emergency departments (EDs) and inpatient units of four hospitals. Pretest probability data were collected in real time and the D‐dimer was measured in a central laboratory. Criterion standard was CPTA interpretation by two independent radiologists combined with clinical outcome at 30 days. Results: Of 678 patients enrolled, 126 (19%) were PE+ and 93 (14%) had pneumonia. Use of either Wells’ ≤ 4 or RGS ≤ 6 produced similar results. For example, with RGS ≤ 6 and standard threshold (< 500 ng mL^?1), D‐dimer was negative in 110/678 (16%), and 4/110 were PE+ (posterior probability 3.8%) and 9/110 (8.2%) had pneumonia. With RGS ≤ 6 and a threshold < 1000 ng mL^?1, D‐dimer was negative in 208/678 (31%) and 11/208 (5.3%) were PE+, but 10/11 missed PEs were subsegmental and none had concomitant DVT. Pneumonia was found in 12/208 (5.4%) with RGS ≤ 6 and D‐dimer < 1000 ng mL^?1. Conclusions: Doubling the threshold for a positive D‐dimer with a PE unlikely pretest probability could reduce CTPA scanning with a slightly increased risk of missed isolated subsegmental PE, and no increase in rate of missed pneumonia.     

Referent d-dimer enzyme-linked immunosorbent assay testing is of limited value in the exclusion of thromboembolic disease: result of a practical study in an ED

OBJECTIVE: The aim of this study was to assess in clinical practice the accuracy of a referent d-dimer enzyme-linked immunosorbent assay for the exclusion of venous thromboembolic disease (VTED). PATIENTS AND METHODS: An observational prospective study took place in an emergency department; 205 consecutive outpatients suspected of having VTED were included. Blood samples were collected at admission for VIDAS DD measurement. Venous thromboembolic disease was confirmed by standard clinical imaging. All patients were followed up at 3 months. RESULTS: Venous thromboembolic disease was confirmed in 57 patients (28%). The sensitivity and negative predictive value of a DD assay lower than 500 ng/mL were 78% (95% confidence interval = 67%-87%) and 84% (95% confidence interval = 73%-90%), respectively. Twelve patients had a false-negative DD with one or more of the following: (a) symptoms reported for more than 15 days (n = 2), (b) prior anticoagulation (n = 3), (c) distal VTED (n = 5), or (d) high clinical probability (n = 3). CONCLUSION: In our cohort of patients, DD was less accurate than previously reported, with an upper estimate of the sensitivity of only 87%.     

D‐dimer testing in the diagnosis of cerebral vein thrombosis: a systematic review and a meta‐analysis of the literature

Summary. Background: Quantitative measurement of circulating D‐dimer, a product of fibrin degradation, has been shown to be a very useful diagnostic tool in the management of patients with suspected deep vein thrombosis and/or pulmonary embolism. Whether D‐dimer can play a similar role in the diagnostic approach to patients with suspected cerebral vein thrombosis (CVT) remains controversial.Methods: Studies evaluating the diagnostic accuracy of the D‐dimer test in the diagnosis of CVT were systematically searched for in the MEDLINE and EMBASE databases (up to July 2011). Weighted mean sensitivity and specificity with 95% confidence intervals (CIs) were calculated with a bivariate random‐effects regression approach.Results: Fourteen studies, for a total of 1134 patients, were included. D‐dimer accuracy was good, with a resulting weighted mean sensitivity of 93.9% (95% CI 87.5–97.1) and weighted mean specificity of 89.7% (95% CI 86.5–92.2), calculated with a bivariate approach. Potential risk factors for false‐negative D‐dimer results included isolated headache, longer duration of symptoms, and limited sinus involvement.Conclusions: Our findings suggest that D‐dimer may be a useful diagnostic tool in the management of patients with suspected CVT. Future prospective studies are warranted to confirm our preliminary findings.     

D-二聚体、血管性假血友病因子抗原和凝血酶原断片对下肢深静血栓形成的诊断价值

目的 探讨血浆D二聚体(DD)、血管性假血友病因子抗原(vWF:Ag)和凝血酶原断片(Fl 2)对下肢深静血栓形成的诊断价值。方法 采用ELISA法检测108例下肢DVT患者及105例非DVT对照者血浆DD、vWF:Ag和Fl 2水平。结果三个指标单独及其各种组合对DVT的诊断灵敏度和阴性预示值为96~99％,和94~100％,三个指标单独或其两两组合诊断DVT的特异性和阳性预示值在45％~76.4％左右,三个指标组合对DVT的诊断灵敏度、特异性、阳性预示值、阴性预示值、试验有效率分别为99.1％、82.90％、85.6％、98.9％、91.1％。结论 三个指标单独及其各种组合都可以用于可疑DVT患者的排除诊断,三指标组合在保持高水平的灵敏度和阴性预示值同时,可以显著提高对DVT的诊断特异性和阳性预示值。