Home About us Contact
|
Home About us Contact | ||
|
|
||
D-dimer
Terms modified by D-dimer Selected AbstractsPlasma hemostatic factors and endothelial markers in four racial/ethnic groups: the MESA studyJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2006P. L. LUTSEY Summary.,Background:,Hemostatic factors and endothelial markers may play some role in racial/ethnic differences in cardiovascular disease (CVD) rates. However, little information exists on hemostatic factors and endothelial markers across racial/ethnic groups. Objectives:,To describe, in four American racial/ethnic groups (Caucasian, Black, Hispanic, and Chinese), mean levels of selected hemostatic factors and endothelial markers. Patients and methods:,Multi-ethnic Study of Atherosclerosis baseline data were used (participant age: 45,84 years). Sex-specific analysis of covariance models, and t -tests for pairwise comparisons, were used to compare means of factors and markers. Adjustments were made for demographics and traditional CVD risk factors. Differences were significant at P < 0.05. Results:,Blacks had the highest levels of factor VIII, D-Dimer, plasmin,antiplasmin (PAP), and von Willebrand factor, among the highest levels of fibrinogen and E-selectin (women only), but among the lowest levels of intercellular adhesion molecule 1 (ICAM-1), and, in men, the lowest levels of plasminogen activator inhibitor-1 (PAI-1). Whites and Hispanics tended to have intermediate levels of factors and markers, although they had the highest levels of ICAM-1, and Hispanics had the highest mean levels of fibrinogen and E-selectin (women only). Chinese participants had among the highest levels of PAI-1, but the lowest, or among the lowest, of all other factors and markers. No soluble thrombomodulin differences were observed. Conclusions:,In this large cohort, hemostatic factor and endothelial marker mean levels varied by race/ethnicity, even after adjustment for traditional CVD risk factors. [source] Prospective study of hemostatic alterations in children with acute lymphoblastic leukemia,AMERICAN JOURNAL OF HEMATOLOGY, Issue 5 2010Paola Giordano In a group of newly diagnosed acute lymphocytic leukemia (ALL) children we evaluated a number of hemostatic and inflammatory markers at diagnosis and at different time points during chemotherapy for the remission induction to identify alterations in the plasma levels of prothrombotic markers before and during the course of chemotherapy. The following plasma markers were evaluated: thrombin-antithrombin complex (TAT), D-Dimer, plasminogen activator inhibitor 1 (PAI-1), antithrombin, fibrinogen, von Willebrand factor (VWF) antigen and high molecular weight VWF (HMW-VWF) multimers, P-selectin, tumor necrosis factor alpha (TNF-,), and interleukin 6 (IL-6). Plasma samples were collected at the following time points: at T0 (baseline) and T1 (+24 days of therapy), T2 (+36 days therapy), and T3 (+64 days therapy). The results show that, at diagnosis, ALL children presented with laboratory signs of increased thrombin generation and fibrin formation (i.e. high TAT and D-dimer levels), fibrinolysis inhibition (i.e. high PAI-1 level), endothelial activation (i.e., high HMW-VWF and soluble P-selectin levels) and inflammation (i.e. high TNF-alpha and IL-6 levels). After starting induction therapy, the thrombin generation markers and inflammatory cytokines significantly decreased. To the opposite, PAI-1 and P-selectin significantly increased, suggesting an insult by chemotherapy on the vascular endothelium. These effects were more evident during steroid administration. Symptomatic venous thromboembolism (VTE) episodes developed in two cases during induction therapy, which did not allow the evaluation of the predictive value for VTE of laboratory markers. Am. J. Hematol., 2010. © 2010 Wiley-Liss, Inc. [source] The Probability of Pulmonary Embolism Is a Function of the Diagnoses Considered Most Likely Before TestingACADEMIC EMERGENCY MEDICINE, Issue 4 2006Christopher Kabrhel MD Abstract Objectives: To determine the frequency of pulmonary embolism (PE) diagnosis when different alternative diagnoses were considered most likely before testing, because the relationship between specific alternative diagnoses and the diagnosis of PE has not been explored. Methods: This study was a preplanned secondary analysis of a prospective study of the diagnosis of pulmonary embolism conducted in the emergency department (ED) of an urban university hospital. Physicians were queried as to their most likely pretest diagnosis when they ordered any of the following tests to evaluate possible PE: D-dimer, contrast-enhanced computed tomography of the chest, ventilation,perfusion lung scan, or pulmonary angiogram. To compare the frequency of PE diagnosis across alternative diagnoses, risk ratios, 95% confidence intervals (CI), and p-values using Fisher's exact test were calculated. Results: Six hundred seven patients were enrolled, and 61 had PE. Physicians thought PE was the most likely pretest diagnosis in 162 (26.7%) patients, and 20.4% (95% CI = 14.4% to 27.4%) of these patients had PE. For four alternative diagnoses, PE was diagnosed less frequently than when PE was considered most likely: musculoskeletal pain (2.2%, 95% CI = 0.4% to 6.2%), anxiety (1.7%, 95% CI = 0.0 to 9.2%), asthma or chronic obstructive pulmonary disease (0, 95% CI = 0.0 to 10.9%), and viral syndrome (0, 95% CI = 0.0 to 14.3%). Conclusions: The frequency of PE is related to the most likely pretest alternative diagnosis. PE is diagnosed infrequently when anxiety, asthma or chronic obstructive pulmonary disease, musculoskeletal pain, or viral syndrome is the most likely alternative diagnosis. [source] Disseminated intravascular coagulation in acute leukemia: clinical and laboratory features at presentationEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2006Masamitsu Yanada Abstract:,Background:,Although there are two major scoring systems for the clinical diagnosis of disseminated intravascular coagulation (DIC), the validity of these systems for leukemia-associated DIC remains to be confirmed. Methods:,By analyzing 125 newly diagnosed acute leukemia patients, we investigated clinical and laboratory features of leukemia-associated DIC, and determined the validity of the two established criteria. Results:,A total of 36 patients (29%) were diagnosed with DIC according to expert opinion, a method regarded as the de facto gold standard. Leukemia-associated DIC is characterized by rare manifestation of organ failure because of thrombosis and no relevance of the platelet count for the diagnosis. The results of receiver operating characteristics analysis favored fibrin degradation product (FDP) rather than D-dimer as the fibrin-related marker test. Although prothrombin time, plasma fibrinogen, and serum FDP levels were significantly different for patients with and without DIC, multivariate analysis identified FDP levels to be the only factor associated with DIC diagnosis. The cut-off level of 15 ,g/mL for FDP was found to be the most effective to differentiate DIC from non-DIC, resulting in diagnostic sensitivity and specificity of 92% and 96%, respectively. The diagnostic results for our patients produced with this FDP-based system were at least comparable with or superior to those obtained with the two currently available scoring systems. Conclusions:,Our findings suggest that an FDP-based criterion may be applicable for the diagnosis of leukemia-associated DIC. Although it appears to be simple and practicable enough for clinical use, prospective validation of this criterion is needed. [source] Correlation of a high D-dimer level with poor outcome in traumatic intracranial hemorrhageEUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2007J.-R. Kuo The correlations between D-dimer and Glasgow Coma Scale (GCS), pupillary light reflex, distance of midline shift on brain computed tomography (CT), and Glasgow Outcome Score (GOS) in patients with trauma/non-trauma intracranial hemorrhage (ICH) are not consistent in studies. Ninety-eight traumatic and 59 non-traumatic ICH patients were studied. Pre-existing venous thrombosis, recent surgery, drug use (aspirin or coumadin), or malignancy, were excluded. D-dimer level was estimated within hours after acute insult, and statistical analyses were used for comparisons between groups. Traumatic ICH patients had higher D-dimer levels than controls (2984 vs. 256 ,g/l; P = 0.001). The GCS, midline shift on brain CT, pupillary reflex, and GOS at 3 months were significantly correlated with high D-dimer value in traumatic patients (individual P < 0.001), but not in the non-traumatic group. Using receiver-operating characteristic curve (ROC), the cutoff point was 1496 ,g/l, with sensitivity and specificity of 100% and 83%, respectively. D-dimer ,1496 ,g/l predicted a poor outcome [adjusted odds ratio (OR) 14.44, 95% CI 1.16,179.27; P = 0.038]. A high D-dimer level is associated with a poor outcome in patients with traumatic ICH. It can be used in addition to neurological assessment to predict the outcome. [source] Utility of an Initial D-dimer Assay in Screening for Traumatic or Spontaneous Intracranial HemorrhageACADEMIC EMERGENCY MEDICINE, Issue 9 2001Mark E. Hoffmann MD Abstract Objective: To evaluate the sensitivity of a D-dimer assay as a screening tool for possible traumatic or spontaneous intracranial hemorrhage. If adequately sensitive, the D-dimer assay may potentially permit omission of a more expensive computed tomography (CT) scan of the head when such hemorrhage is clinically suspected. Methods: Prospective, consecutive, blinded study of patients (age > 16 years) requiring a CT scan of the head for suspected intracranial hemorrhage over a five-month period at a university, Level I trauma center. All study patients had a serum D-dimer assay obtained prior to their CT scans. Sensitivity and specificity, with 95% confidence intervals (95% CIs), of the enzyme-linked immunosorbent assay (ELISA) D-dimer assay for the detection of intracranial hemorrhage were calculated. Results: Of the 319 patients entered in the study, 25 (7.8%) had a CT scan positive for intracranial hemorrhage. Patients with intracranial hemorrhage were more likely to have a positive D-dimer assay (chi-square ? 13.075, p < 0.001). The D-dimer assay had 21 true-positive and four false-negative tests, resulting in a sensitivity of 84.0% (95% CI ? 63.7% to 95.5%) and a specificity of 55.8% (95% CI ? 55.5% to 55.9%). The four false-negative cases included one small intraparenchymal hemorrhage, one small subarachnoid hemorrhage, one moderate-sized intraparenchymal hemorrhage with mid-line shift, and one large subdural hematoma requiring emergent surgery. Conclusions: Due to the catastrophic nature of missing an intracranial hemorrhage in the emergency department, the D-dimer assay is not adequately sensitive or predictive to use as a screening tool to allow routine omission of head CT scanning. [source] Role of the Peripheral Intravenous Catheter in False-positive D-dimer TestingACADEMIC EMERGENCY MEDICINE, Issue 2 2001Alan C. Heffner MD Abstract. Objective: To determine whether inserting a peripheral intravenous catheter (IV) can significantly increase the circulating D-dimer concentration. Methods: Twenty healthy young adult volunteers underwent cannulation of an antecubital vein with a 20-gauge Teflon IV. Time 0 venous blood was drawn during IV insertion. The IV was salinelocked and left in place for 90 minutes, at which time a second venipuncture was performed in a contralateral antecubital vein (+90 min). A qualitative D-dimer assay [erythrocyte-agglutination assay, SimpliRED (SRDD)] and a quantitative spectrophotometric assay [enzyme-linked immunosorbent assay (EIA), Dimertest Gold] were performed on all samples. Time 0 means (±SD) were compared with +90 min means by paired t-test, and SRDD pairs were compared with McNemar's test. Results: Time 0 initial venipuncture blood samples yielded a mean D-dimer concentration of 15 ± 24 ng/mL, with 2/20 SRDD tests read as positive (95% CI = 1% to 32%). At +90 min, the D-dimer concentration was 33 ± 21 ng/mL (p = 0.04 vs time 0), with 5/20 SRDD tests read as positive (95% CI = 9% to 49%, p = 0.248). Conclusions: Insertion of an IV increased the circulating D-dimer concentration (determined by EIA), but did not lead to a significant increase in false-positive conversion of the SRDD. An effort should be made to perform D-dimer testing on "first-stick" blood to optimize specificity. However, a strongly positive D-dimer reaction cannot be ascribed to the presence of an IV. [source] Does an alteration of dialyzer design and geometry affect biocompatibility parameters?HEMODIALYSIS INTERNATIONAL, Issue 2 2006Karel OPATRNÝ Jr. Abstract The aim of the study was to assess the biocompatibility profile of a newly developed high-flux polysulfone dialyzer type (FX-class dialyzer). The new class of dialyzers incorporates a number of novel design features (including a new membrane) that have been developed specifically in order to enhance the removal of small- and middle-size molecules. The new FX dialyzer series was compared with the classical routinely used high-flux polysulfone F series of dialyzers. In an open prospective, randomized, crossover clinical study, concentrations of the C5a complement component, and leukocyte count in blood and various thrombogenicity parameters were evaluated before, and at 15 and 60 min of hemodialysis at both dialyzer inlet and outlet in 9 long-term hemodialysis patients using the FX60S dialyzers and, after crossover, the classical F60S, while in another 9 patients, the evaluation was made with the dialyzers used in reverse order. The comparison of dialyzers based on evaluation of the group including all procedures with the FX60S and the group including procedures with the F60S did not reveal significant differences in platelet count, activated partial thromboplastin times, plasma heparin levels, platelet factor-4, D-dimer, C5a, and leukocyte count at any point of the collecting period. Both dialyzer types showed a significant increase in the plasma levels of the thrombin-antithrombin III complexes; however, the measured levels were only slightly elevated compared with the upper end of the normal range. Biocompatibility parameters reflecting the behavior of platelets, fibrinolysis, complement activation, and leukopenia do not differ during dialysis with either the FX60S or the F60S despite their large differences in design and geometry features. Although coagulation activation, as evaluated by one of the parameters used, was slightly higher with the FX60S, it was still within the range seen with other highly biocompatible dialyzers and therefore is not indicative of any appreciable activation of the coagulation system. Thus, the incorporation of various performance-enhancing design features into the new FX class of dialyzers does not result in a deterioration of their biocompatibility profile, which is comparable to that of the classical F series of dialyzers. [source] ORIGINAL ARTICLE: Comparison of a point of care device against current laboratory methodology using citrated and EDTA samples for the determination of D-dimers in the exclusion of proximal deep vein thrombosisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2010P. M. BAKER Summary D-dimer estimation is a routine part of diagnostic algorithms for the exclusion of venous thromboembolism (VTE). We evaluated a point of care device, Biosite Triage (Inverness Medical UK, Cheshire, UK) for the estimation of D-dimers in both samples taken into citrate and EDTA against our routine laboratory D-dimer (Liatest D-dimer, Diagnostica Stago, Reading, UK) performed on the STA-R Evolution. With informed consent, 102 consecutive patients presenting with possible deep vein thrombosis (DVT) were enrolled and D-dimers along with Wells scores and compression ultrasonography (CUS) were recorded. Using the manufacturers' recommended cut offs of 500 ,g/l fibrinogen equivalent units and 400 ,g/l for the Stago and Triage, respectively, sensitivity, specificity, positive and negative predictive values were calculated. These were 1.00, 0.42, 0.17, and 1.00 for the Triage machine using citrate samples, 1.00, 0.32, 0.14, and 1.00 using EDTA samples and 1.00, 0.29, 0.16, and 1.00 for the Stago Liatest assay, respectively. Three patients had significantly higher results for the Stago Liatest D-dimer assay compared with the Biosite Triage device although ultrasound scans were negative. Conclusion: The Biosite Triage D-dimer assay performed on either citrate or EDTA samples is comparable with the Stago Liatest laboratory D-dimer assay when used in conjunction with clinical pretest probability scoring and CUS for the exclusion of DVT. [source] Influence of temperature and time before centrifugation of specimens for routine coagulation testingINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2009G. L. SALVAGNO Summary The accurate standardization of the preanalytical phase is of pivotal importance for achieving reliable results of coagulation tests. Because information on the suitable storage conditions for coagulation testing is controversial, we aimed at investigating the sample stability with regard to the temperature and time before centrifugation. The activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen and D-dimer were assayed in specimens collected from 26 consecutive patients on antivitamin K therapy on the ACL TOP analyzer. Three primary 3.6-ml siliconized evacuated tubes containing 0.109 mol/l buffered trisodium citrate were sequentially collected from each patient. These three tubes were mixed, pooled and divided into seven identical aliquots. The first aliquot was immediately centrifuged according to the standard protocol [1500 g for 15 min at room temperature (RT)] and analyzed. The other aliquots were left for 3, 6 and 24 h, respectively, at RT or 4 °C, and then centrifuged and analyzed. Test results were compared with those obtained on the reference specimen. Statistically significant prolongations were observed for aPTT in all the samples. Such differences exceeded the analytical quality specifications for desirable bias in the samples stored for 24 h. A significant reduction, yet comprised within the desirable bias, was observed for PT and fibrinogen in uncentrifuged specimens stored at RT for 3 and 6 h. No significant biases could be recorded in D-dimer. In conclusion, a 6-h storage of uncentrifuged specimens at either RT or 4 °C may still be suitable to achieve results of routine coagulation testing comprised within the analytical quality specifications for desirable bias. [source] Hemostatic Defect in Baboons Autotransfused Treated Plasma to Simulate Shed BloodJOURNAL OF CARDIAC SURGERY, Issue 6 2006C. Robert Valeri M.D. This study was done to determine how autotransfusion of nontreated plasma and plasma treated with urokinase with and without aprotinin affected hemostasis in healthy baboons. Methods: A 500-mL volume of blood was collected from the baboon, a 250-mL volume of plasma was isolated, and the RBCs were reinfused. Three baboons were autotransfused untreated plasma. Four baboons received plasma that had been treated with 3000 IU/mL urokinase at +37°C for 30 minutes. Eight baboons received plasma that had been treated first with urokinase 3000 IU/mL at +37°C for 30 minutes and then with aprotinin (1000 KIU/mL). Bleeding time, fibrinogen degradation products (FDP), D-dimer, and alpha-2 antiplasmin levels were measured. Results: During the 4-hour period following autotransfusion of the urokinase-aprotinin-treated plasma, the levels of D-dimer and FDP were significantly higher and fibrinogen and alpha-2 antiplasmin levels were significantly lower than those levels seen after the autotransfusion of nontreated plasma. FDP and D-dimer levels showed significant positive correlations with prothrombin time (PT) and activated partial thromboplastin time (aPTT). A significant negative correlation was observed between thrombin time (TT) and fibrinogen level. A significant positive correlation was observed between bleeding time and D-dimer level and a significant negative correlation between the bleeding time and the fibrinogen level. Conclusions: The infusion of a volume of urokinase or urokinase-aprotinin treated autologous plasma equivalent to 15% of the blood volume was not associated with a bleeding diathesis in healthy baboons. [source] Periodontal health improves systemic inflammatory and haemostatic status in subjects with coronary heart diseaseJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2005L. Montebugnoli Abstract Objectives: A relationship between poor oral health and coronary heart disease (CHD) and systemic inflammatory and haemostatic factors has been recently documented in an Italian population. The present study was performed to assess whether intensive dental care may produce a periodontal improvement along with a change in systemic inflammatory and haemostatic factors. Material and Methods: The study population consisted of 18 males aged 40,65 years with proven CHD and elevated values of systemic inflammatory and haemostatic factors. A detailed description of their oral status was given by using two different dental indices (clinical periodontal sum score and clinical and radiographic sum score). Blood samples were taken for measurement of the following systemic markers of inflammation [(C-reactive protein (CRP), leucocytes, fibrinogen)] and haemostatic factors [(von Willebrand factor, fibrin D-dimer and oxidized-low density lipoprotein (Ox-LDL)]. All parameters were determined in each subject at baseline, after 4 months as a control and 3 months after an intensive protocol of scaling and root planing. anova for repeated measures was used for the statistical analysis. Results: No statistical difference was found between values at baseline and at the 4-month-control. All oral indexes showed a significant decrease (p<.01) 3 months after periodontal treatment. All systemic inflammatory indexes decreased but only the decrease in CRP reached statistical significance (p<.05). A significant decrease (p<.01) was also found as regards Ox-LDL among haemostatic factors. Conclusions: Preliminary results from the present study suggest an association between poor oral status and CHD, and provide evidence that the improvement of periodontal status may influence the systemic inflammatory and haemostatic situation. [source] Prospective Evaluation of Real-time Use of the Pulmonary Embolism Rule-out Criteria in an Academic Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 9 2010Jeffrey A. Kline MD Abstract Objectives:, The pulmonary embolism rule-out criteria (PERC rule) is a nine-component decision rule derived to exclude pulmonary embolism (PE) without the use of formal diagnostic testing (D-dimer, computed tomography pulmonary angiography, ventilation,perfusion lung scanning, or venous ultrasonography) when all nine components are negative ("PERC negative"). This study examined whether clinicians who document PERC negative also document results of all nine components of the PERC rule. Methods:, This was a pilot study at a single-center, urban teaching emergency department (ED) with a residency program in emergency medicine. Patients were over 17 years of age with at least one of nine predefined chief complaints. Clinicians were asked three questions regarding suspicion for PE, intent to use the PERC rule, and the result. Charts were independently reviewed by two authors for fidelity of the nine PERC components. Patients were followed for PE outcome at 14 days. Results:, The study examined 526 patients cared for by 82 clinicians, who indicated suspicion for PE in 183 of 526 (35%) and intent to use the PERC rule in 115 of 526 (22%) cases, of whom 65 of 115 were documented as PERC negative. No formal test for PE was ordered in 49 of 65 (75%), and 46 of 49 had incomplete documentation to support PERC negative. The most common deficiency was omission of two risk factors for PE in the rule (prior venous thromboembolism or recent surgery). Six patients had PE diagnosed within 14 days, but none of these had been deemed PERC negative. Conclusions:, Clinicians seldom document all nine data elements of the PERC rule in patients they deem PERC negative. These data suggest the need for paper or electronic aids to support use of the PERC rule. ACADEMIC EMERGENCY MEDICINE 2010; 17:1016,1019 © 2010 by the Society for Academic Emergency Medicine [source] High D-dimer levels increase the likelihood of pulmonary embolismJOURNAL OF INTERNAL MEDICINE, Issue 2 2008L. W. Tick Abstract. Objective., To determine the utility of high quantitative D-dimer levels in the diagnosis of pulmonary embolism. Methods., D-dimer testing was performed in consecutive patients with suspected pulmonary embolism. We included patients with suspected pulmonary embolism with a high risk for venous thromboembolism, i.e. hospitalized patients, patients older than 80 years, with malignancy or previous surgery. Presence of pulmonary embolism was based on a diagnostic management strategy using a clinical decision rule (CDR), D-dimer testing and computed tomography. Results., A total of 1515 patients were included with an overall pulmonary embolism prevalence of 21%. The pulmonary embolism prevalence was strongly associated with the height of the D-dimer level, and increased fourfold with D-dimer levels greater than 4000 ng mL,1 compared to levels between 500 and 1000 ng mL,1. Patients with D-dimer levels higher than 2000 ng mL,1 and an unlikely CDR had a pulmonary embolism prevalence of 36%. This prevalence is comparable to the pulmonary embolism likely CDR group. When D-dimer levels were above 4000 ng mL,1, the observed pulmonary embolism prevalence was very high, independent of CDR score. Conclusion., Strongly elevated D-dimer levels substantially increase the likelihood of pulmonary embolism. Whether this should translate into more intensive diagnostic and therapeutic measures in patients with high D-dimer levels irrespective of CDR remains to be studied. [source] Cardiac troponin I and plasma D-dimer are related to proximal and bilateral extension of clots and right cardiac dysfunction in patients with pulmonary embolismJOURNAL OF INTERNAL MEDICINE, Issue 5 2007L. Masotti No abstract is available for this article. [source] Evaluation of D-dimer during pregnancyJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 4 2009Ayano Nishii Abstract Aim:, The purpose of the present study was to elucidate the change of D-dimer and the possibility of deep vein thrombosis screening by D-dimer during pregnancy. Methods:, One thousand, one hundred and thirty-one pregnant women were enrolled in the study from April 2006 to March 2007. D-dimer was measured by latex immunoassay at 6 to 14 and 30 to 36 weeks of gestation, respectively, and the veins of the lower extremities were examined by ultrasound at 30 to 36 weeks of gestation. Results:, The mean and standard error of D-dimer was 1.1 ± 1.0 µg/mL in the first trimester and 2.2 ± 1.1 µg/mL in the third trimester, and both values were significantly higher than adult values. In addition, D-dimer significantly increased during pregnancy. D-dimer was not significantly different between singleton and twin pregnancies in the first trimester, but in the third trimester, the values of twin pregnancies were higher than singleton pregnancies (2.2 ± 1.6 vs 3.7 ± 2.5 µg/mL). The mean value of D-dimer of ultrasonographically positive women was 2.6 ± 2.0 µg/mL, which was significantly higher than the value for negative woman during the third trimester (2.2 ± 1.6 µg/mL). The positive predictive value was 7.4% and negative predictive value was 95.5% for ultrasonographically positive women when D-dimer was set at 3.2 µg/mL. Conclusion:, We clearly found a change of D-dimer during pregnancy. When D-dimer was higher than 3.2 µg/mL, the percentage of ultrasonographically positive women was high. We propose that women with D-dimer higher than 3.2 µg/mL are closely monitored for prevention of pulmonary thromboembolism. [source] Effect of oral melatonin on the procoagulant response to acute psychosocial stress in healthy men: a randomized placebo-controlled studyJOURNAL OF PINEAL RESEARCH, Issue 4 2008Petra H. Wirtz Abstract:, Acute mental stress is a potent trigger of acute coronary syndromes. Catecholamine-induced hypercoagulability with acute stress contributes to thrombus growth after coronary plaque rupture. Melatonin may diminish catecholamine activity. We hypothesized that melatonin mitigates the acute procoagulant stress response and that this effect is accompanied by a decrease in the stress-induced catecholamine surge. Forty-five healthy young men received a single oral dose of either 3 mg melatonin (n = 24) or placebo medication (n = 21). One hour thereafter, they underwent a standardized short-term psychosocial stressor. Plasma levels of clotting factor VII activity (FVII:C), FVIII:C, fibrinogen, D-dimer, and catecholamines were measured at rest, immediately after stress, and 20 min and 60 min post-stress. The integrated change in D-dimer levels from rest to 60 min post-stress differed between medication groups controlling for demographic and metabolic factors (P = 0.047, = 0.195). Compared with the melatonin group, the placebo group showed a greater increase in absolute D-dimer levels from rest to immediately post-stress (P = 0.13; = 0.060) and significant recovery of D-dimer levels from immediately post-stress to 60 min thereafter (P = 0.007; = 0.174). Stress-induced changes in FVII:C, FVIII:C, fibrinogen, and catecholamines did not significantly differ between groups. Oral melatonin attenuated the stress-induced elevation in the sensitive coagulation activation marker D-dimer without affecting catecholamine activity. The finding provides preliminary support for a protective effect of melatonin in reducing the atherothrombotic risk with acute mental stress. [source] Oral melatonin reduces blood coagulation activity: a placebo-controlled study in healthy young menJOURNAL OF PINEAL RESEARCH, Issue 2 2008Petra H. Wirtz Abstract:, Melatonin has previously been suggested to affect hemostatic function but studies on the issue are scant. We hypothesized that, in humans, oral administration of melatonin is associated with decreased plasma levels of procoagulant hemostatic measures compared with placebo medication and that plasma melatonin concentration shows an inverse association with procoagulant measures. Forty-six healthy men (mean age 25 ± 4 yr) were randomized, single-blinded, to either 3 mg of oral melatonin (n = 25) or placebo medication (n = 21). One hour thereafter, levels of melatonin, fibrinogen, and D-dimer as well as activities of coagulation factor VII (FVII:C) and VIII (FVIII:C) were measured in plasma. Multivariate analysis of covariance and regression analysis controlled for age, body mass index, mean arterial blood pressure, heart rate, and norepinephrine plasma level. Subjects on melatonin had significantly lower mean levels of FVIII:C (81%, 95% CI 71,92 versus 103%, 95% CI 90,119; P = 0.018) and of fibrinogen (1.92 g/L, 95% CI 1.76,2.08 versus 2.26 g/L, 95% CI 2.09,2.43; P = 0.007) than those on placebo explaining 14 and 17% of the respective variance. In all subjects, increased plasma melatonin concentration independently predicted lower levels of FVIII:C (P = 0.037) and fibrinogen (P = 0.022) explaining 9 and 11% of the respective variance. Melatonin medication and plasma concentration were not significantly associated with FVII:C and D-dimer levels. A single dose of oral melatonin was associated with lower plasma levels of procoagulant factors 60 min later. There might be a dose,response relationship between the plasma concentration of melatonin and coagulation activity. [source] Sex, age and normal post-anticoagulation D-dimer as risk factors for recurrence after idiopathic venous thromboembolism in the Prolong study extensionJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 9 2010B. COSMI Summary.,Background:,The PROLONG randomized study showed that patients with an abnormal D-dimer after anticoagulation suspension for a first unprovoked episode of venous thromboembolism (VTE) benefited from anticoagulation resumption. Patients with normal D-dimer after anticoagulation suspension had a low recurrence rate (4.4% patient,years) but their anticoagulation optimal duration remained uncertain. Objectives:,To assess whether sex and age, in combination with normal D-dimer, are risk factors for VTE recurrence in patients enrolled in the PROLONG study extended follow-up. Methods:,D-dimer was measured at 1 month after anticoagulation suspension. Patients with a normal D-dimer did not resume anticoagulants, whereas patients with an abnormal D-dimer were randomized either to resume or not anticoagulants. Primary outcome was recurrent VTE. Results:,After excluding patients resuming anticoagulants for abnormal D-dimer, recurrences were higher in males than females [7.4% patient-years , 47/639 vs. 4.3% patient-years , 27/626; hazard ratio (HR) = 1.7; P = 0.027] and in patients aged 65 or older than in younger patients (8.4% patient-years , 50/598 vs. 3.6% patient-years , 24/667; HR = 2.1; P = 0.003). In patients with normal D-dimer and younger than 65, recurrences were higher in males than in females (5.1% vs. 0.4% patient,years; adjusted HR = 10.6; P = 0.023) and both females and males aged 65 years or older had more recurrences (6.6% and 8.1% patient-years, respectively, adjusted HR: 16.0; P = 0.008 and 16.0; P = 0.008, respectively) than females younger than 65. Conclusions:,In patients with idiopathic VTE and a normal D-dimer at 1 month after anticoagulation suspension, females younger than 65 had a very low risk of recurrence. [source] Evaluation of a new quantitative highly sensitive D-dimer assay for exclusion of venous thromboembolismJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 9 2009P. DE MOERLOOSE [source] Response of fractional synthesis rate (FSR) of fibrinogen, concentration of D-dimer and fibrinolytic balance to physical activity-based intervention in obese childrenJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2008P. BALAGOPAL Summary.,Background:,Physical activity-induced reduction in obesity-related hyperfibrinogenemia in children has been reported. The underlying mechanisms remain elusive. Further, the effect of such interventions on fibrinolysis in children is scarce. Objectives: To investigate in obese children, before and after a physical activity-based intervention: (i) the mechanistic role of fractional synthesis rate (FSR) of fibrinogen in the reduction of hyperfibrinogenemia; and (ii) the changes in fibrinolytic factors. Methods:,Subjects included 21 (age > 14 < 18 years; Tanner stage, IV,V) children (15 obese, BMI >95%tile for age and sex and six lean, BMI <85%tile). After baseline measurements of FSR of fibrinogen, and concentrations of fibrinogen, D-dimer, PAI-1 and t-PA in all children, studies were repeated after a 3-month randomized controlled physical activity-based lifestyle intervention in obese children only. Results:,FSR of fibrinogen was higher (P = 0.002) in the obese (vs. lean) group, which was reduced (P = 0.001) after intervention. This almost completely accounted for the reduction in obesity-related hyperfibrinogenemia. High levels of D-dimer decreased (P = 0.001) after intervention, whereas fibrinolysis was not enhanced. Conclusions:,The direct reduction in the FSR of fibrinogen and the remarkable correlation between the magnitudes of reduction in fibrinogen FSR and concentration signify a mechanistic role for FSR in the regulation of physical activity-induced reversal of hyperfibrinogenemia in obese children. The congruent reductions in the FSR of fibrinogen and the concentrations of fibrinogen and D-dimer in response to intervention despite depressed fibrinolysis suggest an overall improvement in the hypercoagulable state in obese children with physical activity-based lifestyle intervention. [source] Common genetic variants associated with plasma fibrin D-dimer concentration in older European- and African-American adultsJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2008L. A. LANGE Summary.,Background and Objectives:,D-dimer is a hemostasis marker that reflects ongoing fibrin formation and degradation. There is significant inter-individual and inter-population variability in D-dimer concentration, but whether genetic factors underlie these differences is largely unknown. We hypothesized that common coagulation gene variants contribute to differences in circulating D-dimer concentration. Methods:,The setting was European-American (EA; n = 1858) and African-American (AA; n = 327) unrelated older adults from the Cardiovascular Health Study (CHS), in which we genotyped SNPs in 42 genes related to blood coagulation and fibrinolysis. Results:,Several fibrinogen gene polymorphisms, including the Thr312Ala A, chain variant and the FGG-10034 C/T variant, were associated with ,20% higher plasma D-dimer levels in EA (false discovery rate < 5% for covariate-adjusted model). There was also some evidence that a Pro41Leu variant of the PLAU gene encoding urinary plasminogen activator and non-coding polymorphism of the plasminogen activator inhibitor type 1 gene (SERPINE1) were associated with higher plasma D-dimer in EA. There were no significant associations between the studied coagulation or fibrinolysis gene SNPs and plasma D-dimer levels in the smaller AA sample. However, each standard deviation increase in European ancestry assessed by ancestry-informative gene markers was associated with ,10% lower mean D-dimer levels in AA. Conclusions:,Together, common coagulation/fibrinolysis gene SNPs explained only ,2% of the variance in plasma D-dimer levels in EA. These findings suggest that the association of D-dimer with risk of vascular outcomes may be mediated largely by environmental factors, other genes, and/or genetic interactions. [source] Diagnostic accuracy of D-dimer test for exclusion of venous thromboembolism: a systematic reviewJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2 2007M. DI NISIO Summary.,Background: The reported diagnostic accuracy of the D-dimer test for exclusion of deep vein thrombosis (DVT) and pulmonary embolism (PE) varies. It is unknown to what extent this is due to differences in study design or patient groups, or to genuine differences between D-dimer assays. Methods: Studies evaluating the diagnostic accuracy of the D-dimer test in the diagnosis of venous thromboembolism were systematically searched for in the MEDLINE and EMBASE databases up to March 2005. Reference lists of all included studies and of reviews related to the topic of the present meta-analysis were manually searched for other additional potentially eligible studies. Two reviewers independently extracted study characteristics using standardized forms. Results: In total, 217 D-dimer test evaluations for DVT and 111 for PE were analyzed. Several study design characteristics were associated with systematic differences in diagnostic accuracy. After adjustment for these features, the sensitivities of the D-dimer enzyme-linked immunofluorescence assay (ELFA) (DVT 96%; PE 97%), microplate enzyme-linked immunosorbent assay (ELISA) (DVT 94%; PE 95%), and latex quantitative assay (DVT 93%; PE 95%) were superior to those of the whole-blood D-dimer assay (DVT 83%; PE 87%), latex semiquantitative assay (DVT 85%; PE 88%) and latex qualitative assay (DVT 69%; PE 75%). The latex qualitative and whole-blood D-dimer assays had the highest specificities (DVT 99%, 71%; PE 99%, 69%). Conclusions: Compared to other D-dimer assays, the ELFA, microplate ELISA and latex quantitative assays have higher sensitivity but lower specificity, resulting in a more confident exclusion of the disease at the expense of more additional imaging testing. These conclusions are based on the most up-to-date and extensive systematic review of the topic area, including 184 articles, with 328 D-dimer test evaluations. [source] Clinical probability and alveolar dead space measurement for suspected pulmonary embolism in patients with an abnormal D-dimer test resultJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2006O. SANCHEZ Summary.,Background: Most patients with suspected pulmonary embolism (PE) have a positive D-dimer test and undergo diagnostic imaging. Additional non-invasive bedside tests are required to reduce the need for further diagnostic tests. Objectives: We aimed to determine whether a combination of clinical probability assessment and alveolar dead space fraction measurement can confirm or exclude PE in patients with an abnormal D-dimer test. Methods: We assessed clinical probability of PE and alveolar dead space fraction in 270 consecutive in- and outpatients with suspected PE and positive D-dimer. An alveolar dead space fraction < 0.15 was considered normal. PE was subsequently excluded or confirmed by venous compression ultrasonography, spiral computed tomography and a 3-month follow-up. Radiologists were unaware of the results of clinical probability and capnography. Results: PE was confirmed in 108 patients (40%). Capnography had a sensitivity of 68.5% (95% confidence interval [CI]: 58.9,77.1%) and a specificity of 81.5% (95% CI: 74.6,87.1%) for PE. Forty-five patients (16.6%) had both a low clinical probability and normal capnography (sensitivity: 99.1%, 95% CI: 94.9,100%) and 34 patients (12.6%) had both a high clinical probability and abnormal capnography (specificity: 100%, 95% CI: 97.7,100%). Conclusion: Capnography alone does not exclude PE accurately. The combination of clinical probability and capnography accurately excludes or confirms PE and avoids further testing in up to 30% of patients. [source] Thrombin generation during reperfusion after coronary artery bypass surgery associates with postoperative myocardial damageJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2006P. RAIVIO Summary.,Background: Cardiopulmonary bypass and coronary artery bypass grafting (CABG) result in significant thrombin generation and activation of fibrinolysis. Thrombin contributes to myocardial ischemia,reperfusion injury in animal studies, but the role of thrombin in myocardial damage after CABG is unknown. Objectives: We measured thrombin generation and fibrin turnover during reperfusion after CABG to evaluate their associations with postoperative hemodynamic changes and myocardial damage. Methods: One hundred patients undergoing primary, elective, on-pump CABG were prospectively enrolled. Plasma prothrombin fragment F1+2 and D-dimer were measured preoperatively and at seven time points thereafter. Mass of the Mb fraction of creatine kinase (Ck-Mbm) and troponin T (TnT) were measured on the first postoperative day. Results: Reperfusion induced an escalation of thrombin generation and fibrin turnover despite full heparinization. F1+2 during early reperfusion associated with postoperative pulmonary vascular resistance index. F1+2 at 6 h after protamine administration correlated with Ck-Mbm (r = 0.40, P < 0.001) and TnT (r = 0.44, P < 0.001) at 18 h postoperatively. Patients with evidence of myocardial damage (highest quintiles of plasma Ck-Mbm and TnT) had significantly higher F1+2 during reperfusion than others (P < 0.002). Logistic regression models identified F1+2 during reperfusion to independently associate with postoperative myocardial damage (odds ratios 2.5,4.4, 95% confidence intervals 1.04,15.7). Conclusions: Reperfusion caused a burst in thrombin generation and fibrin turnover despite generous heparinization. Thrombin generation during reperfusion after CABG associated with pulmonary vascular resistance and postoperative myocardial damage. [source] Elevated levels of soluble fibrin or D-dimer indicate high risk of thrombosisJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2006H. WADA Summary.,Background:,Fibrin-related markers such as soluble fibrin (SF) and D-dimer are considered useful for the diagnosis of thrombosis. However, the evidence for diagnosis of thrombosis by fibrin-related markers is not well-established. Objective:,To evaluate the cutoff values of D-dimer and SF in the diagnosis of thrombosis. Patients and Methods:,Plasma concentrations of SF and D-dimer were measured in 784 inpatients suspected of having thrombosis between 1 August 2003 and 31 December 2004, and then correlated with thrombosis. Results and Conclusions:,Plasma concentrations of D-dimer and SF were significantly higher in patients with disseminated intravascular coagulation (DIC), deep vein thrombosis (DVT) and cerebral thrombosis, compared with those in patients without thrombosis. When cutoff values of > 3.0 ,g mL,1 for D-dimer and > 6.0 ,g mL,1 for SF were used for the diagnosis, more than 50% of patients (with the exception of liver transplant patients and postoperative patients) had thrombosis. Receiver operating characteristic analysis showed that SF was more useful than D-dimer for the diagnosis of thrombosis (i.e. DVT and DIC). The cutoff value of D-dimer (7.87 ,g mL,1) was the same for DVT and DIC, while that of SF was slightly lower for DVT (7.05 ,g mL,1) than for DIC (8.60 ,g mL,1). Our findings suggest that high levels of plasma fibrin-related markers reflect high risk for thrombosis. [source] Combined use of clinical pretest probability and D-dimer test in cancer patients with clinically suspected deep venous thrombosisJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2006M. DI NISIO Summary.,Background: The value of the D-dimer (DD) test in combination with the clinical pretest probability (PTP) has not been evaluated in cancer patients with suspected deep vein thrombosis (DVT), whereas this group of patients usually accounts for 10,25% of clinically suspected DVT. Methods: A cohort of 2066 consecutive patients with clinically suspected DVT was investigated. Patients were judged to be positive or negative for DVT according to the outcomes of serial compression ultrasound and a 3-month follow-up period with imaging test verification of the symptomatic cases. Diagnostic accuracy indices of the DD test according to the PTP score were assessed in patients with and without cancer. Results: Of the cohort, 244 (11%) were known to have cancer at presentation. A venous thromboembolic event was diagnosed in 41% of the patients with cancer and in 22% of the patients without malignancy. Among the cancer patients, 17% were considered to have a low PTP, 35% a moderate and 41% a high PTP. The negative predictive value (NPV) of the DD test was 100% (95%CI, 85,100) and 97% (95% CI, 88,99) among cancer patients with low PTP or low-moderate PTP. In the absence of malignancy, the corresponding NPV were 98% and 97%, respectively. The specificity of the DD test progressively decreased moving from the low to the higher PTP. Conclusions: In cancer patients with clinically suspected DVT, a negative DD might be useful in excluding the diagnosis within the low or low-moderate PTP groups. More studies are warranted to confirm these findings. [source] Management studies using a combination of D-dimer test result and clinical probability to rule out venous thromboembolism: a systematic reviewJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 11 2005A. J. TEN CATE-HOEK Summary.,Background:,While the number of patients with suspected venous thromboembolism (VTE) referred to hospital emergency units increases, the proportion in whom the diagnosis can be confirmed is decreasing. A more efficient but safe diagnostic strategy is needed. Objective:,To evaluate the safety of withholding anticoagulant therapy in patients suspected of VTE based on a diagnostic work-up that combines a clinical decision rule (CDR) with a D-dimer test result without performing additional diagnostic tests. Patients/methods:,We searched Medline (January 1996,December 2004)-related articles and reference lists of studies in English for prospective clinical studies that managed consecutive patients suspected of VTE and used a D-dimer assay combined with an explicit CDR or implicit clinical judgment. Results:,We identified 11 studies in which 6837 consecutive outpatients suspected of VTE were included. In the combined management studies, the overall rate of thromboembolic events was nine out of 2056 patients (0.44 %, 95% CI 0.2%,0.83%) in whom anticoagulants were withheld based on the D-dimer result and a low clinical score. Similar results were obtained with qualitative and quantitative D-dimer tests and with different decision rules. The rate of exclusion varied between 30% and 50% and was highest with a low incidence of VTE among those referred. Conclusion:,Withholding anticoagulant treatment in patients suspected of VTE on the basis of a work-up consisting of a low clinical probability combined with either a qualitative or quantitative D-dimer test result is safe. [source] D-Dimer test in cancer patients with suspected acute pulmonary embolismJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2005M. DI NISIO Summary.,Background:,The safety of a D-dimer (DD) measurement in cancer patients with clinically suspected pulmonary embolism (PE) is unclear. Objectives:,The aim of this study was to assess the accuracy of the DD test in consecutive patients with clinically suspected PE with and without cancer. Methods:,The diagnostic accuracy of DD (Tinaquant D-dimer) was first retrospectively assessed in an unselected group of patients referred for suspected PE (n = 350). Subsequently, the predictive value of the DD was validated in a group of consecutive inpatients and outpatients with clinically suspected PE prospectively enrolled in a management study (n = 519). The results of the DD test in cancer patients were assessed according to the final diagnosis of PE and the 3-month clinical follow-up. Results:,In the first study group, DD showed a sensitivity and a negative predictive value (NPV) of 100% and 100% in patients with cancer and 97% and 98% in those without malignancy, respectively. In the validation cohort, the sensitivity and NPV of DD were both 100% (95% CI 82%,100% and 72%,100%, respectively), whereas in patients without malignancy, the corresponding estimates were 93% (95% CI 87%,98%) and 97% (95% CI, 95%,99%), respectively. The specificity of DD was low in patients with (21%) and without cancer (53%). Conclusions:,A negative DD result safely excludes the diagnosis of PE in patients with cancer. Because of the low specificity, when testing 100 patients with suspected PE, a normal DD concentration safely excludes PE in 15 patients with cancer and in 43 patients without cancer. [source] D-dimer levels during delivery and the postpartumJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2 2005M. EPINEY Summary.,Background: D-dimer (DD) measurement has proved to be very useful to exclude venous thromboembolism (VTE) in outpatients. However, during pregnancy, the progressive increase as well as the interindividual variations of DD means that in this instance they are of poor value to rule out VTE. Only a few studies have reported measurements of DD levels in the postpartum. Objectives: To measure DD sequentially in the puerperium in order to determine when DD levels return to values obtained in non-pregnant women and can again be used in the exclusion of VTE. Patients and methods: After uncomplicated pregnancies, 150 women delivering at term either vaginally (n = 100) or by cesarean section (n = 50) were included. DD levels were measured immediately following delivery and next at days 1, 3, 10, 30 and 45. Results: There was a marked elevation of DD at delivery, especially when instrumental. All DD measurements were above 500 ng mL,1 at delivery, at day 1 and at day 3 postpartum. A sharp decrease in DD was observed between day 1 and day 3, followed by a slight increase at day 10. At day 30 and day 45, respectively, 79% and 93% of women in the vaginal delivery group and 70% and 83% in the cesarean group had levels below 500 ng mL,1. Bleeding, breastfeeding and heparin prophylaxis did not modify DD levels significantly. Conclusion: Using the Vidas DD new assay, our study provides reference intervals for DD in the postpartum period. Using a cut-off at 500 ng mL,1, DD measurement for ruling out VTE was found to be useful again 4 weeks after delivery. [source] | ||||||||||||||||||||||||||||