Differential Diagnosis for Easy Bruising

The patient's lab results show elevated levels of von Willebrand factor antigen, ristocetin cofactor, and factor VIII activity, which can be associated with various bleeding disorders. Here is a differential diagnosis organized into categories:

• Single Most Likely Diagnosis
  • Von Willebrand Disease (VWD): The patient's elevated von Willebrand factor antigen and ristocetin cofactor levels, along with easy bruising, suggest VWD as a likely diagnosis. VWD is a common inherited bleeding disorder characterized by a deficiency or dysfunction of von Willebrand factor.
• Other Likely Diagnoses
  • Hemophilia A: Although the patient's factor VIII activity is elevated, hemophilia A (a deficiency in factor VIII) can sometimes present with elevated factor VIII levels due to chronic inflammation or other factors. However, this is less likely given the patient's easy bruising and elevated von Willebrand factor levels.
  • Other Bleeding Disorders: Other bleeding disorders, such as platelet function disorders or fibrinogen disorders, could also be considered, although the patient's lab results do not specifically suggest these conditions.
• Do Not Miss Diagnoses
  • Thrombotic Thrombocytopenic Purpura (TTP): Although TTP is a rare condition, it can present with easy bruising and thrombocytopenia. The patient's platelet count is within the normal range, but TTP can sometimes present with normal platelet counts. Missing this diagnosis could be deadly, as TTP requires prompt treatment.
  • Disseminated Intravascular Coagulation (DIC): DIC is a life-threatening condition that can present with easy bruising, thrombocytopenia, and coagulopathy. Although the patient's lab results do not specifically suggest DIC, it is essential to consider this diagnosis due to its high mortality rate.
• Rare Diagnoses
  • Factor VIII Inhibitor: A rare condition characterized by the development of antibodies against factor VIII, which can lead to bleeding complications. Although the patient's factor VIII activity is elevated, a factor VIII inhibitor could be considered in the differential diagnosis.
  • Glanzmann's Thrombasthenia: A rare platelet function disorder characterized by a deficiency in platelet glycoproteins. Although the patient's platelet count is within the normal range, Glanzmann's thrombasthenia could be considered in the differential diagnosis due to its association with easy bruising.