Biomaterial Database

Automated nephelometry of fibrinogen: analytical performance and observations during thrombolytic therapy. 1988

J J Hoffmann, and M A Verhappen

Department of Clinical Laboratories, Catharina Hospital, Eindhoven, The Netherlands.

We evaluated the performance of an automated nephelometric determination of fibrinogen, which is an integral part of the prothrombin time assay, in a new coagulation analyzer, the ACL-810 (Instrumentation Laboratory). Results were compared with those by a total clottable protein assay and with the thrombin clotting time assay for fibrinogen. In normal and slightly abnormal plasma, the performance of the ACL method was quite satisfactory (CV 3-10%). However, in abnormal plasma (prolonged prothrombin times because of heparin or oral anticoagulants) the accuracy of the ACL method was poor. Nor could the instrument determine fibrinogen in clearly lipemic plasma. In plasma containing high concentrations of fibrin(ogen) degradation products (FDP), collected during thrombolytic therapy with streptokinase-containing drugs, the ACL method gave spuriously high values for fibrinogen concentration. We determined that this was mainly because of interference by intermediate FDP (fragment Y). Finally, we demonstrated that early FDP (fragment X) increased the ACL results for fibrinogen to the same extent as in the total clottable protein method and that late FDP (fragments D and E) affected the thrombin clotting time method, but not the ACL fibrinogen determination.

UI	MeSH Term	Description	Entries
D009391	Nephelometry and Turbidimetry	Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.	Turbidimetry,Nephelometry,Turbidimetry and Nephelometry
D005338	Fibrin Fibrinogen Degradation Products	Soluble protein fragments formed by the proteolytic action of plasmin on fibrin or fibrinogen. FDP and their complexes profoundly impair the hemostatic process and are a major cause of hemorrhage in intravascular coagulation and fibrinolysis.	Antithrombin VI,Fibrin Degradation Product,Fibrin Degradation Products,Fibrin Fibrinogen Split Products,Degradation Product, Fibrin,Degradation Products, Fibrin,Product, Fibrin Degradation
D005340	Fibrinogen	Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.	Coagulation Factor I,Factor I,Blood Coagulation Factor I,gamma-Fibrinogen,Factor I, Coagulation,gamma Fibrinogen
D005343	Fibrinolytic Agents	Fibrinolysin or agents that convert plasminogen to FIBRINOLYSIN.	Antithrombic Drug,Antithrombotic Agent,Antithrombotic Agents,Fibrinolytic Agent,Fibrinolytic Drug,Thrombolytic Agent,Thrombolytic Agents,Thrombolytic Drug,Antithrombic Drugs,Fibrinolytic Drugs,Thrombolytic Drugs,Agent, Antithrombotic,Agent, Fibrinolytic,Agent, Thrombolytic,Agents, Antithrombotic,Drug, Antithrombic,Drug, Fibrinolytic,Drug, Thrombolytic,Drugs, Antithrombic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001322	Autoanalysis	Method of analyzing chemicals using automation.	Autoanalyses