fibrinogen

FIBRINOGEN ASSAYS GUIDELINES UK 2003



FIBRINOGEN STANDARD 2ND



http://atvb.ahajournals.org/cgi/content/abstract/28/4/758

FIBRINOGEN HAPLOTYPES -NO CAD KOCH2008

GWAS FRAMINGHAM 2007



fibrinogen minutes 2006 XXXXX

ISTH 2008





FBG INTRAINDIVIDUAL VARIABILITY ROUVIER 2002

FIBRINOGEN STUDIES COLLABORATION JAMA 2005



Variability in fibrinogen measurements: an obstacle to cardiovascular risk stratification

rosenson 2001



http://www.clinchem.org/cgi/content/full/50/11/2150



Effect of Specimen Collection on Routine Coagulation Assays and D-Dimer Measurement LIPPI 2004

Among routine coagulation assays, fibrinogen and D-dimer measurements are thought to be more susceptible to variations introduced in the preanalytical phase (2)(3)(4). The term "D-dimer" usually refers to a heterogeneous class of end-stage degradation products of cross-linked fibrin that occur in vivo with a wide range of molecular weights and contain various numbers of the D-dimer motif (5). The strong heterogeneity of D-dimer in plasma might be reflected by most immunoassays (the monoclonal antibodies show variable reactivity with different molecular forms) because the various forms occur naturally in the plasma of patients. This might be particularly true when evaluating D-dimer after continuous blood-sampling because it is conceivable that different samples from the same patients might contain heterogeneous D-dimer isoforms. Some recommended procedures for acquiring samples for coagulation analysis, especially those involving the measurement of D-dimer and fibrinogen by the Clauss method, mandate that the first sample be discarded because tissue thromboplastin released by the trauma of venipuncture could interfere with coagulation assays by activating intrinsic pathway (2). However, in agreement with the earlier report by Rosenson et al. (6), our results demonstrate that a standardized procedure for blood collection does not influence the reliability of in vitro routine coagulation testing. This is particularly true for fibrinogen and D-dimer measurements, as it had been speculated previously that discrepancies might arise from different specimens collected simultaneously from the same patient (2)(6).


atorvastatin on fibrinogen 1998





Immunonephelometric determination of fibrinogen on citrated or heparinized plasma: comparison with functional Clauss method.



As a result, the immunonephelometric method shows reliable performance and clinical sample measurements are not affected by the method used, validating the use of heparinized plasma samples for fibrinogen antigen determination with Dade Behring reagents.




Kinetic Fibrinogen Assay (KFA), a method based on the kinetic reaction of the developing fibrin clot, was used to determine fibrinogen concentration in plasma. Two other methods employing different quantification principles were used for comparison: the von Clauss method and the procedure measuring protein concentration in an isolated and washed plasma clot (World Health Organization [WHO] method). All three methods quantified functional thrombin-coagulable fibrinogen. Tan Am J Clin Path 1995




Comparison of Clauss fibrinogen and fibrinogen measurement derived from aPTT and PT in diabetes mellitus and correlations with markers of glycemic equilibration
Abstract number: P0278
Sobas* F., Hanss† M., Dechavanne* M., Riou* J. P., Drai‡ J., Negrier* C.
‡Centre Hospitalier, Lyon, France *Hôpital Edouard Herriot, Lyon, France; †Hop Cardiologique Lyon, France;
The consequences of fibrinogen glycosylation on fibrinogen polymerization are controversial in the literature. We have compared fibrinogen levels determined with Clauss, prothrombin time derived measurement of fibrinogen (PTd) and activated partial prothrombin time-derived measurement of fibrinogen (aPTTd) in 32 diabetic patients (Sobas et al. Blood Coagul Fibrinolysis, 2002; 13: 61–68) (7 type II and 10 type I diabetic patients without clinical complication, 11 type II and 4 type I diabetic patients with clinical complications, all patients presenting normal range of PT, aPTT and fibrinogen level). We have also correlated the differences between Clauss and derived methods with markers of glycemic equilibration such as glycemia, capillary glucose value and levels of hemoglobin A1C and fructosamine. All coagulation assays (PT, aPTT, Clauss fibrinogen) were performed on an MDA II coagulometer (bioMérieux). To allow comparison of fibrinogen measurements in diabetic samples (Clauss vs. PTd and aPTTd) reference curves were constructed from 30 control plasmas with normal range of PT, aPTT and fibrinogen level. In all the diabetic patients, fibrinogen was lower when using PTd and aPTTd measurements vs. the Clauss method (paired t-test for PTd: mean of differences = -0.49, P < 0.0001; for aPTTd: mean of differences = -0.39, P < 0.0001). In the 18 type II diabetic patients, there are significant correlation between (PTd-Clauss) difference and Glycemia (P = 0.013); Capillary glucose value (P = 0.008) and Haemoglobin A1C (P = 0.031). In the 14 type I diabetic patients, no correlation is observed. In the 11 type II diabetic patients with complications, no correlation is observed. In the 7 type II diabetic patients without complication (PTd-Clauss) difference is correlated with Glycemia (P = 0.034), with Capillary glucose value (P < 0.001) and with hemoglobin A1C (P = 0.023). (aPTTd-Clauss) difference is correlated with fructosamine (P = 0.048) in the 7 type II diabetic patients without complication. The fibrinogen polymerization is abnormal in aPTT and PT tests in diabetic patients when using MDA II coagulometer. The absence of correlation between markers of glycemic equilibration and difference (Clauss fibrinogen-fibrinogen derived methods) may be an help in finding diabetic patients with clinical complications. To cite this abstract use the following format: Journal of Thrombosis and Haemostasis 2003; 1 Supplement 1 July: abstract number







http://www.biomedexperts.com/Abstract.bme/15843224/Interferences_in_coagulation_tests--evaluation_of_the_570-nm_method_on_the_Dade_Behring_BCS_analyser

2005: Junker Ralf; Käse Margit; Schulte Helmut; Bäumer Ruth; Langer Claus; Nowak-Göttl UlrikeInterferences in coagulation tests--evaluation of the 570-nm method on the Dade Behring BCS analyser.Clinical chemistry and laboratory medicine : CCLM / FESCC 2005;43(2):244-52.
The Dade Behring BCS is a coagulation analyser with optical reaction detection (standard 405 nm). The present study was conducted to evaluate measurement at 570 nm for analyses in interfering plasma samples. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and D-dimer in normal (n=50), lipaemic (n=60), icteric (n=113), and haemolytic (n=58) samples were measured at 405 and 570 nm. As they are unaffected by the optical properties of the sample, the mechanical STAcompact analyser (Roche Diagnostics) and an ELISA technique were defined as the "comparison" methods. The percentage of valid PT results using the 570-nm method varied from 54% (lipaemic samples) to 97% (haemolytic samples). Valid aPTT measurements were found in 67% (lipaemic samples) up to 93% (icteric samples) of samples. Fibrinogen measurement revealed valid results in 58% (lipaemic samples) to 100% (haemolytic samples) of samples. The number of valid D-dimer results varied from 28% (lipaemic material) up to 100% (haemolytic material). Significant inter-method differences were found: aPTT in lipaemic (BCS 405 vs. 570 nm) and icteric samples (STAcompact vs. BCS 405 and 570 nm); fibrinogen in lipaemic (BCS 405 vs. 570 nm), icteric (BCS 405 vs. 570 nm; STAcompact vs. BCS 570 nm) and haemolytic samples (STAcompact vs. BCS 405 and 570 nm). Differences between the BCS 570-nm and the STAcompact methods were in most cases low and less pronounced than between the BCS 570- and 405-nm methods, making the BCS 570-nm method an alternative to measurement at 405 nm. Limitations have to be taken into account regarding lipaemic plasma.