1例D-二聚体远高于FDP原因分析

D-二聚体(D-dimer)水平的增高反映了体内血栓形成和纤溶活性增强,为临床继发性纤溶亢进的标志物.但在检测过程中受到一些因素的影响,从而造成D-二聚体假性增高,常见原因为类风湿因子(rheumatoid factor,RF)、异嗜性抗体等.现报道一例可能由大分子免疫球蛋白IgM影响,导致患者血浆中的D-二聚体检测结...     

不同抗干扰能力STA-Liatest D-Di试剂盒检测类风湿患者D-二聚体水平效果比较研究

目的 分析比较不同抗干扰能力STA-Liatest D-Di试剂盒检测类风湿患者D-二聚体水平的效果.方法 本研究选取本院就诊的确诊类风湿患者104例,使用STA-Liatest D-Di试剂盒进行DD120CN的检测,并与标准免疫比浊法检测结果进行比较,同时对两种试剂盒的灵敏度与特异性进行比较和评价.结果 本研究中,纳入研究的受试对象包含女性80例,男性24例,对于RF水平小于50 IU/mL的49例患者进行检测,STA-Liatest D-Di 1000IU/mL试剂盒检测的D-二聚体水平为8.59±1.16 ng/mL,STA-Liatest D-Di 50IU/mL试剂盒检测结果为8.65±1.21ng/mL,两种试剂盒间差异无统计学意义.对于RF水平大于50 IU/mL的55例患者进行检测,STA-Latest D-Di 50IU/mL试剂盒检测结果更高,P＜0.01.在女性受试对象中STA-Liatest D-Di 1000IU/mL试剂盒检测的特异度更高,P＜0.05.在男性受试对象中,两种试剂盒检测的灵敏度均为90.00％,STA-Latest D-Di 1000IU/mL试剂盒检测的特异性更高,P＜0.01.结论 检测工作中,对于RF水平大于50 IU/mL的患者来说STA-Liatest D-Di 50IU/mL更显优势.且无论对于男性还是女性患者,STA-Liatest D-Di 50IU/mL试剂盒和STA-Liatest D-Di 1000 IU/mL试剂盒对于检测风湿患者D-二聚体水平的灵敏度均较高;STA-Liatest D-Di 1000 IU/mL试剂盒的检测特异性则稍高于STA-Latest D-Di 50IU/mL试剂盒.     

血浆D-二聚体、FDP、和尿ALB/Cr联合检测对早期糖尿病肾病临床诊断的价值

目的 探究血浆D-二聚体、FDP和尿ALB/Cr联合检测对早期糖尿病肾病临床诊断的价值.方法 选取我院2019年1月至2020年10月收治的113例早期糖尿病肾病患者作为EDN组,另选取50例单纯2型糖尿病患者作为T2DM组,并选取50例健康体检者作为健康对照组,检测三组受试者血浆D-二聚体、FDP的水平和尿ALB/Cr比值,并比较单个指标检测与联合检测对早期糖尿病肾病诊断的价值.结果 EDN组血浆D-二聚体和FDP均高于T2DM组和健康对照组,尿ALB/Cr比值低于T2DM组和健康对照组,差异有统计学意义(P<0.05),血浆D-二聚体、FDP和尿ALB/Cr联合检测诊断早期糖尿病肾病的特异性与灵敏度分别为95.38％和96.21％,较单个指标检测高.结论 血浆D-二聚体、FDP和尿ALB/Cr联合检测对早期糖尿病肾病的临床诊断具有一定的参考价值.     

卵巢癌患者外周血D-二聚体、FIB水平与IL-6动态变化的研究

目的:探讨卵巢癌患者血浆D-二聚体、纤维蛋白原(FIB)、白细胞介素6(IL-6)动态变化及其对卵巢癌诊断中的价值和临床意义。方法:选择卵巢癌患者65例、35例卵巢良性肿瘤患者和30例健康体检者做对照,取卵巢癌患者和对照组的血清及血浆,用胶乳凝集法测定血浆中的D-二聚体、FIB含量,用ELISA法测定IL-6水平。结果:卵巢癌患者FIB、IL-6、D-二聚体水平明显高于对照组和卵巢良性肿瘤组,差异有显著统计学意义(P<0.05);卵巢良性肿瘤患者FIB、IL-6、D-二聚体水平与正常对照组无显著差异(P>0.05),癌症组FIB、IL-6、D-二聚体随着临床分期的升高而递增,相关性分析表明,FIB与IL-6、D-二聚体呈正相关(r=0.31,r=0.56)。结论:FIB、IL-6、D-二聚体联合检测对于卵巢癌的早期诊断、分期及判断预后具有重要的临床价值。     

血浆D-二聚体检测对急性缺血性脑卒中的临床意义

目的:分析血浆D-二聚体对急性缺血性脑卒中患者的诊断价值。方法:对113例住院急性缺血性脑卒中患者(卒中组),应用颗粒增强型免疫浊度法检测血浆D-二聚体水平,并与100例正常体检者(对照组)比较。通过绘制ROC曲线确定D-二聚体最佳临界值,并计算其对急性缺血性脑卒中诊断的敏感度和特异度。结果:卒中组血浆D-二聚体水平(1.97±0.13mg/L)明显高于对照组(0.34±0.09mg/L),差异有统计学意义(P0.05)。血浆D-二聚体诊断急性缺血性脑卒中最佳临界值为1.53mg/L,此时的敏感度为83.26%,特异度为66.32%。结论:血浆D-二聚体水平检测对诊断急性缺血性脑卒中有一定临床意义。     

D-二聚体与急性心肌梗死溶栓治疗的关系

目的探讨D-二聚体在急性心肌梗死溶栓治疗中的动态变化情况。方法选取急性心肌梗死(acute myocardial infarction,AMI)患者50例为实验组,以同期健康体检者30名为正常对照组,分别检测AMI组及对照组的D-二聚体基础水平;AMI组根据是否进行溶栓治疗分为溶栓组及非溶栓组,根据ST段是否抬高分为ST段抬高型心肌梗死(ST-segment elevation myocardial infarction,STEMI)组与非ST段抬高型心肌梗死(non-ST-segment elevation myocardial infarction,NSTEMI)组,分别检测各组治疗前及治疗后6h、12h、24h的D-二聚体水平,对各组数据间差异进行统计学分析。结果基础状态AMI组D-二聚体水平高于对照组,但差异不具有统计学意义(P>0.05);溶栓组与非溶栓组治疗前血浆D-二聚体水平差异无统计学意义(P>0.05);溶栓组与非溶栓组治疗后6h、12h、24h血浆D-二聚体水平与治疗前相比均有显著性差异(P<0.05);STEMI组治疗前血浆D-二聚体水平高于NSTEM组,但差异无统计学意义(P>0.05);STEMI组与NSTEMI组治疗后6h、12h、24h血浆D-二聚体水平与治疗前相比均有显著性差异(P<0.05)。结论 D-二聚体检测能显示AMI溶栓治疗的动态变化,对AMI的诊断、治疗和预后有较好的指导意义。     

吕梁地区健康孕妇不同孕期D-二聚体的参考区间建立

目的 1.观察就诊于我院的孕妇血浆D-二聚体水平的变化趋向,明确妊娠因素对孕妇血浆D-二聚体水平的影响。2.建立吕梁市健康孕妇不同孕期D-二聚体的参考区间。3.探讨本研究所确立的参考区间对产科凝血止血相关疾病诊疗的指导意义。方法选取2016年7月至2017年2月就诊于山西省汾阳医院的健康孕产妇632例、健康非孕妇女100例、DIC孕妇10例、静脉血栓孕妇15例,运用胶乳免疫比浊法定量检测其血浆D-二聚体的浓度。以健康孕妇的检测数据制定D-二聚体的相应参考区间,并和所选健康非孕妇女、DIC孕妇、静脉血栓孕妇的检测数据进行比对分析。结果 1.孕妇血浆D-二聚体水平显著高于非孕妇女人群,现阶段临床检验科室所使用的D-二聚体疾病界定值主要针对的是非孕人群,不适用于孕妇群体;孕妇血浆D-二聚体水平随孕周增加而逐渐增高。2.吕梁市健康孕妇人群血浆D-二聚体的95%参考区间为:≤13w:≤0.835 mg/L;14-27w:≤1.87 mg/L;≥28w:≤2.91mg/L。3.采用本研究所制定的参考区间来评估10例DIC孕妇和15例静脉血栓孕妇的D-二聚体检测值,均判断为为阳性结果,初步验证了本研究所制定的参考区间的有效性。结论本研究初步建立了基于胶乳免疫比浊法的吕梁市孕妇血浆D-二聚体参考区间。运用该参考区间可以提高D-二聚体对孕妇人群凝血止血相关疾病的诊断价值。     

TM、PIC、D-二聚体联合诊断骨外伤术后静脉血栓的价值分析

目的 探讨TM、PIC、D-二聚体在诊断骨外伤术后患者静脉血栓形成中的价值分析.方法 选择2016年2月1日至2017年2月1日我院收治的创伤性四肢骨折患者96例作为研究对象,所有患者均接受骨折内固定手术.术后4～5d进行彩色多普勒结合静脉造影检查,诊断出术后静脉血栓形成患者48例,作为观察组,术后未出现静脉血栓形成患者48例,作为对照组.观察两组患者术后的血栓调节蛋白(TM)、纤溶酶-抗纤溶酶复合物(PIC)和D-二聚体.结果 术后观察组患者的TM(9.12 ±2.09 IU/mL)、PIC(1.21 ±0.71 μg/mL)和D-二聚体(5.37±2.14 ng/mL)含量均显著高于对照组TM(7.21±1.68IU/mL)、PIC(0.92 ±0.24 μg/mL)和D-二聚体(2.34 ±0.66ng/mL),差异具有统计学意义(P＜0.05).回归分析显示D-二聚体、TM、PIC均与术后血栓的形成具有相关性(P均＜0.05);三者联合诊断对静脉血栓诊断受试者工作曲线下面积为0.903,诊断灵敏度为87.31％,特异性也高达85.05％.三者联合检测的灵敏度87.31％高于TM、PIC和D-二聚体单一检测(22.96％、35.85％、49.79％) (P ＜0.05);三者联合检测的准确度86.39％高于TM、PIC和D-二聚体单一检测(49.38％、58.38％、72.27％) (P ＜0.05).结论 检测骨外伤患者术后TM、PIC、D-二聚体指标含量的变化,联合检测有助于早期诊断静脉血栓形成,对预警静脉血栓形成有重要价值.     

不同肺部疾病患者血小板计数和血浆D-二聚体水平分析

目的:检测分析不同肺部疾病患者血小板计数和血浆D-二聚体水平变化。方法:测定95例涂阳肺结核、110例结核性胸膜炎、38例肺炎及45例肺癌患者入院治疗前血小板计数及血浆D-二聚体水平,比较不同疾病组之间以及与健康对照组测定水平的差异。结果:涂阳肺结核、结核性胸膜炎和肺癌组血小板计数明显高于健康对照组,差异有统计学意义(P0.05);涂阳肺结核、结核性胸膜炎明显高于肺癌组(P0.05)。所有疾病组的血浆D-二聚体水平均明显高于健康对照组,差异有统计学意义(P0.05),以结核性胸膜炎组最高;结核性胸膜炎组和肺癌组高于细菌性肺炎组和肺结核组(P0.05)。结论:血小板计数和血浆D-二聚体水平测定有利于临床医师了解上述患者凝血功能和/或血栓性病变。     

急性期脑梗死患者血浆纤溶指标水平变化

目的:检测分析急性期脑梗死患者纤溶指标的血浆水平变化。方法:测定40例急性期脑梗死患者(病例组)血浆纤维蛋白原(FIB)、纤维蛋白降解产物(FDP)、D-二聚体(D-Dimer)、纤溶酶原活性(PLG:A)等指标水平,并与30例健康人群(对照组)进行统计学比较。结果:病例组FIB、FDP和D-Dimer水平明显高于对照组(P0.01);PLG:A活性明显降低于对照组(P0.05)。结论:急性期脑梗死患者呈现高凝及纤溶激活状态。     

Measurement of plasma fibrin D-dimer levels with the use of a monoclonal antibody coupled to latex beads

Recently, monoclonal antibody (DD-3B6) to fibrin D-dimer was prepared and coupled to latex beads to provide a specific test (Dimertest) for fibrinolysis. The purpose of this study was to evaluate the Dimertest assay as a clinical laboratory test for the measurement of plasma fibrin D-dimer derivatives. The Dimer-test assay specifically detected 2 micrograms/mL of purified fibrin D-dimer or fibrin D-dimer/fragment E complex added to afibrinogenemic plasma but did not detect 500 micrograms/mL of either fibrinogen fragments X, D, E, or 160 micrograms/mL cross-linked fibrinogen. The fibrin(ogen) degradation product (FDP) assays of American Dade or Wellcome Diagnostics detected 5.0 micrograms/mL of fibrin D-dimer and from 1 to 10 micrograms/mL of the other FDPs. Twenty-eight percent of 150 random plasma samples assayed from hospitalized patients were positive for fibrin D-dimer derivatives. Plasma samples from 152 patients suspected of having disseminated intravascular coagulation (DIC) were assayed for serum FDP (Wellcome Diagnostics) and plasma fibrin D-dimer derivatives. Samples from 69% of patients with serum FDP levels less than 10 micrograms/mL, and more than 90% of those with serum FDP levels greater than 10 micrograms/mL, were positive for fibrin D-dimer derivatives. Dimertest results were not modified by heparin, streptokinase, freeze-thawing, or clotting plasma. Serum fibrinogen-related antigens were immunoadsorbed from Dimer-test positive sera by anti-fibrinogen antibody and formalin-fixed Cowan I strain Staphylococcus aureus. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein blotting with the use of monoclonal antibody DD-3B6 demonstrated a protein band with similar mobility to purified D-dimer. The measurement of plasma fibrin D-dimer derivatives by the Dimertest assay is a rapid, sensitive, and specific laboratory test for fibrinolysis. The Dimertest assay has proven to be a useful addition to the clinical laboratory and should be helpful in the diagnosis and management of patients with diseases associated with fibrinolysis.     

Incidence and possible reasons for discordant results between positive FDP and negative D-dimer latex assays in clinical specimens.

In general, FDP and D-dimer values have a correlation in clinical conditions associated with disseminated intravascular coagulation(DIC) or coagulation activation. However, there are some patients with discordant results who demonstrate elevated FDP and negative D-dimer results by latex agglutination assays. The incidence and possible reasons for the discordance between FDP and D-dimer results were investigated through simultaneous measurements (n = 763) from clinical patients with suspected DIC or coagulation activation. 24.8% (189/763) of samples with elevated FDP were negative for D-dimer assays by the latex agglutination method. Further detailed analysis on randomly-selected discordant samples (n = 41) revealed that the most common reason for the discordance was the lower sensitivity of the semiquantitative latex agglutination method for D-dimer, compared with quantitative enzyme or other latex immunoassay. The other contributing factors to the discordance were accelerated fibrinogenolysis without secondary fibrinolysis, elevated soluble fibrin monomer and rheumatoid factor.     

Clinical usefulness of the measurement of plasma D-dimer levels

To evaluate the clinical usefulness of D-dimer, various effects on the measurement of D-dimer were examined. Although both fibrinolytic and fibrinogenolytic products were detected by the measurement of FDP, only fibrinolytic products were detected by the measurement of D-dimer. In patients with DIC and other thrombo-embolic diseases, plasma D-dimer levels were significantly higher than in normal persons. A significant positive correlation between plasma D-dimer and serum FDP was found in DIC patients. In patients with DIC associated with acute promyelocytic leukemia, which is thought to be an increased fibrinogenolysis state, serum FDP was higher than the plasma D-dimer which suggests that increased fibrinogenolysis affects the result of serum FDP measurement. Plasma D-dimer significantly increased 5 minutes after endoscopic embolization with thrombin in the patients with esophageal varices. However serum FDP increased 30 minutes after the treatment, which suggests that the D-dimer is more useful for rapid detection of coagulo-fibrinolytic change than serum FDP. Plasma D-dimer was significantly higher in patients with cerebral infarction and increased with age. These finding suggest the usefulness of plasma D-dimer measurement for the specific and rapid evaluation of coagulo-fibrinolytic activation and thrombo-embolic state.     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

D-二聚体在慢性肺源性心脏病患者中检测的临床意义

目的检测慢性肺源性心脏病急性加重期和临床缓解期患者血浆D-二聚体（D-dimer）含量的变化,分析其临床意义。方法慢性肺源性心脏病急性加重期和临床缓解期患者及正常对照组各30例,以ELISA法测定血浆D-dimer含量。结果慢性肺源性心脏病患者急性加重期和临床缓解期血浆D-dimer含量分别为（2.62±0.91）、（2.16±0.78）μg/L,均较正常对照者的（1.74±0.63）μg/L明显增高,差异有统计学意义（P〈0.05）;而急性加重期血浆D-dimer含量也明显高于缓解期（P〈0.05）。结论 D-dimer增高是慢性肺源性心脏病临床病理生理改变的结果,而且与疾病的严重程度有关。     

Analysis of antibody reactivity for FDP D-dimer fragments by Western blotting

We evaluated three test kits for fibrin degradation products (FDP) D-dimer. We found that six of 217 plasma sample values obtained by Nanopia test were markedly higher than the values obtained using the other two kits. The regression equation for 211 samples (excluding six) was y=0.64x+3.05 (y: Nanopia, x: LIAS AUTO) and the correlation coefficient was 0.915. Therefore, we classified these samples into three categories, namely correlated(y< 1.0x), incompatible (y= 1.0x-2.9x) and markedly incompatible (y> or =3.0x). Selected samples, eight correlated, four incompatible and four markedly incompatible, were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western blotting(WB). WB analysis using anti-fibrinogen antibody showed that both high molecular weight fragments of cross-linked fibrin (HMW-XDP) and DD/E fragments were present in the correlated samples, but there was less HMW-XDP than DD/E in the incompatible samples and mostly DD/E (HMW-XDP was significantly less than DD/E) in the markedly incompatible samples. These data suggest that plasma FDP samples that contain mostly DD/E and little HMW-XDP demonstrated markedly incompatible values using the three D-dimer test kits. These data was reflected by markedly elevated plasmin alpha2-plasmin inhibitor complex values in the incompatible and markedly incompatible samples. Unfortunately, we did not directly demonstrate these phenomena by WB analysis with two anti-D-dimer antibodies used Nanopia or LPIA reagent. In the near future, we expect that standardization of FDP D-dimer assay will be accomplished.     

Measurement of plasma D-dimer for diagnosis of deep venous thrombosis

Venography was performed on fifty-six patients suspected of having deep venous thrombosis (DVT) of the legs. The accuracy of the D-dimer measurement in plasma using two latex tests and an enzyme-linked immunosorbent assay (ELISA) was compared with that of usual determination of total fibrin(ogen) degradation products (FDPs) in serum with respect to the presence of DVT. The three D-dimer tests were clearly superior to the FDP assay, but only the ELISA could accurately rule out the diagnosis of DVT with a predictive value of 100% when plasma D-dimer level was less than 200 micrograms/L. However, this test cannot be used for positive diagnosis (false positive rate of 69%). Thus, plasma D-dimer measurement with ELISA allows identification of patients in whom further investigation by means of more specific tests (venography or plethysmography) is indicated in order to establish the diagnosis of DVT. In contrast to this, sensitivity of the two latex tests studied was low (60 and 76%, respectively), which makes them unsuitable for emergency screening. In addition, the potential of D-dimer dosage for diagnosis of DVT in hospitalized patients is hampered by the presence of associated conditions that are responsible for elevated plasma levels in most cases.     

Clinical significance of a new fibrinogen/fibrin degradation products(FDP) test using plasma samples for the diagnosis of fibrinogenolysis and fibrinolysis

Recently, a new fibrinogen/fibrin degradation products(FDP) test using monoclonal antibodies against FDP(LPIA FDP-P: FDP-P) has been developed, which is able to measure FDP directly in plasma. The objective of this study is to clarify clinical significance of the test in the diagnosis of fibrinogenolysis and fibrinolysis in comparison with a conventional FDP test using polyclonal antibodies against fibrinogen(FDP-S) and D-dimer test using monoclonal antibodies against D-dimer(D-D). The monoclonal antibodies used in FDP-P test was shown to recognize fragment X, Y and D1 derived from fibrinogen digested by urokinase, and was also to recognize XDP fragments, D-dimer and D derived from cross-linked fibrin digested by tissue plasminogen activator using SDS-PAGE and immunoblotting analysis. There was a good correlation of FDP levels between FDP-P test and FDP-S test. However, levels of FDP in both tests were discrepant in several samples. There was a tendency that the levels of FDP were higher in FDP-S test than in FDP-P test. Such discrepancy was suggesting that soluble fibrin monomer complex(FM) was recognized by the antibodies used in FDP-S test, but not recognized by the antibodies used in FDP-P test. There was also a good correlation of FDP levels between FDP-P test and D-D test. However, the levels of FDP in both tests were discrepant in several samples. The levels of FDP were higher in FDP-P test than in D-D test. These discrepant samples had lower levels of antiplasmin and higher levels of plasmin antiplasmin complex(PIC), and also showed XDP fragments, D-dimer, X, Y, and D1 by using SDS-PAGE. These observations suggest that D-D test measures only fibrinolytic fragments, while FDP-P test measures fibrinogenolytic fragments as well as fibrinolysis. In results, the FDP-P test was confirmed to be a useful tool to examine fibrinogenolysis as well as fibrinolysis more specifically than the conventional FDP test.     

类风湿患者DD和AT-Ⅲ检测的临床意义

目的检测类风湿关节炎（RA）患者血浆D-二聚体（DD）及抗凝血酶Ⅲ（AT-Ⅲ）表达水平,探讨其在RA中的临床意义。方法选择RA患者36例为RA组,正常对照组30例,测定其血浆DD、AT-III及血浆C反应蛋白（CRP）水平。结果 RA组患者血浆DD水平为（289.36±71.75）μg/L,显著高于正常对照组的（132.25±38.63）μg/L;血浆AT-III水平为（56.2±12.70）%,明显低于对照组的（92.40±3.80）%,差异均有统计学意义（P〈0.05）。相关性分析显示,RA组患者血浆DD、AT-III水平与DAS28评分具有相关性（r=0.32,P〈0.01;r=-0.72,P〈0.01）。RA组患者经治疗病情缓解后（DAS28〈2.6）血浆DD水平为（141.38±32.75）μg/L,显著低于治疗前的（289.36±71.75）μg/L,差异有统计学意义（P〈0.01）,与正常对照组比较差异无统计学意义（P〉0.05）;RA组患者经治疗病情缓解后血浆AT-III水平为（96.20±4.20）%,显著高于治疗前的（56.2±12.7）%,差异有统计学意义（P〈0.01）,与正常对照组比较差异无统计学意义（P〉0.05）。结论血浆DD及AT-III水平与RA患者的病情活动有关,可反映心血管病变危险性,对RA患者的病情判断及预后估计有重要的评判价值。     

Fibrin degradation product D-dimer in the diagnosis of pulmonary embolism

Summary The study objective was to determine the specificity and sensitivity of plasma concentrations of D-dimer, a fibrin degradation product, as a marker for ongoing thrombotic and thrombolytic events in pulmonary embolism. A prospective study was performed in 74 patients with suspected pulmonary embolism who appeared in the emergency room with dyspnea and/or chest pain.The presence of pulmonary embolism was established by positive findings either in pulmonary angiography or lung scan. D-dimer concentrations were determined in all patients. In 11 patients with positive pulmonary angiography, D-dimer concentrations were monitored for 6–12 days.D-dimer concentrations were determined by a quantitative enzyme-linked immunoassay. Plasma probes of 26 patients (16 with/10 without positive pulmonary angiography) were reassayed with a semiquantitative latex agglutination assay. D-dimer levels were significantly higher in patients with pulmonary embolism (>1000 ng/mL in 41 out of 43) than in those without (<1000 ng/mL in all 21 patients) (p<0.01).The sensitivity and specificity for the ELISA were found to be 95% and 100%, respectively, for establishing the diagnosis of pulmonary embolism. In the latex assay the values were 81% and 60%, respectively.It is concluded that in patients with dyspnea and/or chest pain, determination of D-dimer in plasma by ELISA adds a valuable tool to the noninvasive diagnostic procedure for pulmonary embolism. From the time-course of D-dimer values we conclude that this assay might be valuable up to at least 6 days after symptom onset. The assay, however, is unreliable in malignancies or after surgery.Abbreviations apPE angiographically proven pulmonary embolism - hpPE highly probable pulmonary embolism - imPE highly improbable pulmonary embolism - rPE pulmonary embolism ruled out - pPE possible pulmonary embolism