Differential Diagnosis for Abnormal Bleeding with Normal Prothrombin Time

• Single Most Likely Diagnosis
  • (d) von Willebrand’s disease: This condition is characterized by a deficiency or dysfunction of von Willebrand factor, which is crucial for platelet adhesion and protection of factor VIII from degradation. It leads to abnormal bleeding, particularly mucocutaneous bleeding, and has a normal prothrombin time (PT) because PT measures the extrinsic and common coagulation pathways, not the function of von Willebrand factor or platelets.
• Other Likely Diagnoses
  • (c) hemophilia: Hemophilia A and B are due to deficiencies of factor VIII and factor IX, respectively. While they primarily affect the intrinsic pathway and thus the partial thromboplastin time (PTT), patients with hemophilia can experience bleeding complications. However, the PT is typically normal because the defect lies in the intrinsic pathway, not the extrinsic pathway measured by PT.
  • (a) heparin overdose: Heparin primarily affects the intrinsic and common coagulation pathways, leading to an elevated PTT. However, in cases of heparin overdose, the PT can be normal or slightly elevated, but significant bleeding can occur due to the anticoagulant effect.
• Do Not Miss Diagnoses
  • (b) cirrhosis: While cirrhosis can lead to coagulopathy due to decreased production of clotting factors by the liver, it often affects both PT and PTT. However, early or mild cases might present with a normal PT, and it's crucial not to miss cirrhosis due to its significant implications on liver function and overall patient management.
• Rare Diagnoses
  • Other rare bleeding disorders such as factor XIII deficiency, or disorders affecting fibrinogen (like afibrinogenemia or dysfibrinogenemia), could present with abnormal bleeding and a normal PT, especially if the defect does not significantly impact the extrinsic pathway. These conditions are less common and might require specific tests for diagnosis.