D D-Dimer DEFINITION Protein fragments that are formed from the degradation of cross-linked fibrin. They are specific for fibrin degradation products (fibrinolysis). This is a specific method of detecting active coagulation and fibrinolysis. TYPICAL NORMAL RANGE 0.02-0.28 mg/mL PHYSIOLOGY D-dimers form when plasmin digests cross-linked fibrin; the test is more specific than fibrinogen degradation products (FDPs) and indicates both thrombin and plasmin generation. CLINICAL APPLICATIONS CAUSES OF ABNORMALLY HIGH LEVELS: Increased fibrinolysis or decreased clearance of fibrin degradation products by the liver or mononuclear phagocytic system; specific causes include local and disseminated intravascular coagulation, internal hemorrhage, liver disease, chronic renal failure. NEXT DIAGNOSTIC STEP TO CONSIDER IF LEVELS HIGH: Evaluation of the coagulation system: platelet count, antithrombin III, activated coagulation time (ACT) or activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen. If clinical suspicion of pulmonary thromboembolism exists, further evaluation (ultrasound, thoracic radiography and arterial blood gas measurement; possibly angiography) may be indicated. SPECIMEN AND PROCESSING CONSIDERATIONS SPECIMEN: Citrate (blue top) tubes are used; it is important that traumatic venipuncture be avoided to prevent activation of platelets and the coagulation systems; blood and anticoagulant should be mixed thoroughly immediately after collection. Tubes should be completely filled. RELATIVE COST: $$ PEARLS Assays for D-dimers are still being evaluated for their usefulness in veterinary medicine. Quantitive assays are replacing semiquantitative assays, allowing precise monitoring and early detection of thrombosis. AUTHOR: DEBORAH G. DAVIS< div class='tao-gold-member'> Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: D Y G N Stay updated, free articles. Join our Telegram channel Join Tags: Clinical Veterinary Advisor Dogs and Cats Jul 24, 2016 | Posted by admin in SMALL ANIMAL | Comments Off on D Full access? Get Clinical Tree
D D-Dimer DEFINITION Protein fragments that are formed from the degradation of cross-linked fibrin. They are specific for fibrin degradation products (fibrinolysis). This is a specific method of detecting active coagulation and fibrinolysis. TYPICAL NORMAL RANGE 0.02-0.28 mg/mL PHYSIOLOGY D-dimers form when plasmin digests cross-linked fibrin; the test is more specific than fibrinogen degradation products (FDPs) and indicates both thrombin and plasmin generation. CLINICAL APPLICATIONS CAUSES OF ABNORMALLY HIGH LEVELS: Increased fibrinolysis or decreased clearance of fibrin degradation products by the liver or mononuclear phagocytic system; specific causes include local and disseminated intravascular coagulation, internal hemorrhage, liver disease, chronic renal failure. NEXT DIAGNOSTIC STEP TO CONSIDER IF LEVELS HIGH: Evaluation of the coagulation system: platelet count, antithrombin III, activated coagulation time (ACT) or activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen. If clinical suspicion of pulmonary thromboembolism exists, further evaluation (ultrasound, thoracic radiography and arterial blood gas measurement; possibly angiography) may be indicated. SPECIMEN AND PROCESSING CONSIDERATIONS SPECIMEN: Citrate (blue top) tubes are used; it is important that traumatic venipuncture be avoided to prevent activation of platelets and the coagulation systems; blood and anticoagulant should be mixed thoroughly immediately after collection. Tubes should be completely filled. RELATIVE COST: $$ PEARLS Assays for D-dimers are still being evaluated for their usefulness in veterinary medicine. Quantitive assays are replacing semiquantitative assays, allowing precise monitoring and early detection of thrombosis. AUTHOR: DEBORAH G. DAVIS< div class='tao-gold-member'> Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: D Y G N Stay updated, free articles. Join our Telegram channel Join
