From Ning Tang: Hi, George, I come from a clinical laboratory in China. We met a confusing case today and want to get your suggestion: A patient had a prolonged prothrombin time (PT, 20s), partial thromboplastin time (APTT, PTT, 52s) and thrombin time (TT, 127s). Fibrinogen activity is within reference interval (by both Clauss method and TEG), also the patient shows slight bleeding symptoms, is this dysfibrinogenemia? How to confirm it? Thanks for your help!
Hello, Ning Tang, and thank you for your question. From the symptoms and laboratory assay results, I would suggest the patient has disseminated intravascular coagulation (DIC), which is often diagnosed secondary to a number of serious chronic conditions. Though the fibrinogen concentration is usually decreased to below the lower limit of the reference interval, it may remain within the interval or even become slightly elevated because it is an acute phase reactant.
You may confirm DIC by checking for thrombocytopenia and acute hemolytic anemia characterized by the presence of schistocytes on the peripheral blood film. Most importantly, the D-dimer assay is markedly elevated. Dysfibrinogenemia would most likely cause a decreased Clauss fibrinogen assay result and primary fibrinolysis would only slightly prolong the PT and PTT, though it would be associated with an elevated D-dimer. Some secondary tests that parallel the D-dimer are the time-honored fibrin degradation products (FDP) assay and the soluble fibrin monomer assay.