6,502
edits
Changes
→Activated Partial Thromboplastin Time
Conditions in which APTT is prolonged include inherited disorders, such as haemophilia A and B and other congential absences of intrinsic and common factors. Acquired factor deficiency also occurs, for example with vitamin K deficiency, liver dysfunction, prolonged bleeding or disseminated intravascular coagulation. The most common inhibitors found to prolong APTT are the antithrombins, which inhibit the activity of thrombin on the conversion of fibrinogen to fibrin. Examples include heparin and fibrin degradation products.
Conditions in which APTT is prolonged include inherited disorders, such as haemophilia A and B and other congential absences of intrinsic and common factors. Acquired factor deficiency also occurs, for example with vitamin K deficiency, liver dysfunction, prolonged bleeding or disseminated intravascular coagulation. The most common inhibitors found to prolong APTT are the antithrombins, which inhibit the activity of thrombin on the conversion of fibrinogen to fibrin. Examples include heparin and fibrin degradation products.
Occasionally, a shortened APTT is seen. This may reflect increased levels of activated factors in a hypercoagulable state, for example in the earlu stages of DIC<sup>3</sup>.
Occasionally, a shortened APTT is seen. This may reflect increased levels of activated factors in a hypercoagulable state, for example in the early stages of DIC<sup>3</sup>.
===Prothrombin Time===
===Prothrombin Time===