Coagulation Disorders At A Glance

The main causes for acquired coagulation disorders are

Abnormal bleeding can be caused by disorders of the coagulation system, platelet or blood vessels. Blood clotting disorders are either acquired or hereditary conditions. The main causes for acquired coagulation disorders are vitamin K deficiency Leberer disease Disseminated intravascular coagulation development of circulating anticoagulants A severe liver disease (eg. As cirrhosis, fulminant hepatitis, acute fatty liver in pregnant women) can lead to disturbance of hemostasis and synthesis of coagulation factors. Since all clotting factors are synthesized in the liver, both the prothrombin time (PT) and the thromboplastin time (PTT) are elevated in severe liver diseases. (The PT is usually represented as INR). Occasionally, a decompensated liver disease results due to decreased synthesis of alpha-2-antiplasmin to excessive fibrinolysis and bleeding. The most common hereditary disorder of hemostasis is von Willebrand disease (VWD) Congenital coagulation disorders most common are Haemophilia Testing patients for whom a bleeding disorder is suspected, an analysis in the laboratory require starting with prothrombin time (PT) and partial thromboplastin time (PTT). For initial diagnosis, a blood count with platelet counts and peripheral blood smears should be made. The results of these test results restrict the diagnostic possibilities and thus conduct further investigations. Main results of the first tests exclude many poor circulation. Among the main exceptions include the von Willebrand disease and hereditary hemorrhagic telangiectasia. When von Willebrand syndrome, a common disease, the factor VIII deficiency is often very pronounced in order to prolong the PTT. Patients with normal test results, but with symptoms or signs of bleeding, and a positive family history should be tested for the von Willebrand disease; to this, the von Willebrand-factor (vWF) antigen, ristocetin cofactor activity are determined (indirect test on large vWF multimers), the vWF multimer and the factor VIII levels. In thrombocytopenia, the peripheral blood smear often provides clues to the cause. If the smear normal, should be tested for HIV infection. If the HIV test is negative, not pregnant, and no drugs have been ingested, the cause platelet degradation, idiopathic thrombocytopenia is likely. If signs of hemolysis (fragmented erythrocytes in the smear, falling hemoglobin) is suspected thrombotic thrombocytopenia (TTP) or hemolytic uremic syndrome (HUS); However, other hemolytic diseases can show the same results. HUS occurs with hemorrhagic colitis in patients. An “atypical” form of HUS occurs unusually, in people with congenital anomalies of the alternative complement pathway. In TTP and HUS the Coombs test is negative. When the blood and the peripheral blood smear show other cytopenias or abnormal leukocytes, a hematological abnormality of several cell types may be present; in this case, a bone marrow aspiration aspiration and biopsy for diagnosis are necessary. For hemophilia A or B a prolonged thromboplastin time (PTT) speaks (PT) in normal platelets and normal prothrombin time. Factor VIII and Factor IX tests are displayed. Among the PTT prolonging inhibitors include an autoantibody against factor VIII and antibodies to the protein-phospholipid complex. If after mixing with normal plasma in the ratio 1: further a prolonged PTT is 1, one of these inhibitors is believed to be the cause. Prolonged PT with normal platelets and normal PTTweist indicate a factor VII deficiency. The congenital Factor VII deficiency is rare; However, the short half-life of Factor VII results in plasma that the Factor VII values ??decrease more quickly than those of other vitamin K-dependent coagulation factors in patients that start with Warfarinantikoagulation or in patients with early liver disease). Prolonged PT and PTT with thrombocytopenia indicate a disseminated intravascular coagulation, especially in connection with pregnancy complications, sepsis, malignant tumors or shock. Using multiple tests can be suspected by elevated D-dimer levels (or fibrin) and decreasing plasma fibrinogen levels are confirmed. A prolonged PT or PTT with normal platelet count occurs in liver disease, vitamin K deficiency or during anticoagulation with warfarin, unfractionated heparin or the newer orally taken thrombin or Factor Xa. A suspected diagnosis of liver diseases is provided on the basis of medical history and confirmed by increases in serum transaminases and bilirubin; a test for hepatitis is recommended.

Leave a Reply