Differential Diagnosis

The patient presents with a history of persistent bleeding after a tooth extraction, recurrent severe nosebleeds, and a family history of similar bleeding problems. Laboratory studies show a low Factor VIII level, normal platelet count and aggregation, and prolonged partial thromboplastin time.

• Single most likely diagnosis

  • E) von Willebrand disease: This condition is characterized by a deficiency or dysfunction of von Willebrand factor, which is essential for platelet adhesion and protection of factor VIII from degradation. The patient's symptoms, including mucocutaneous bleeding (nosebleeds) and bleeding after a tooth extraction, along with the low factor VIII level and normal platelet aggregation, are consistent with von Willebrand disease. The family history also supports this diagnosis, as von Willebrand disease is often inherited in an autosomal dominant pattern.

• Other Likely diagnoses

  • B) Hemophilia A: Although the factor VIII level is low, which could suggest Hemophilia A, the patient's bleeding pattern (mucocutaneous bleeding) and the fact that the factor VIII level is not severely deficient (as typically seen in Hemophilia A) make this less likely. Hemophilia A usually presents with more severe bleeding into joints and muscles.
  • C) Hemophilia B: This condition involves a deficiency of factor IX, not factor VIII, which is low in this patient. However, the clinical presentation could be considered, but the specific factor deficiency would need to match.

• Do Not Miss diagnoses

  • A) Activated protein C resistance: This condition, often associated with factor V Leiden mutation, typically presents with venous thrombosis rather than bleeding. However, it's crucial to consider in any coagulation disorder evaluation due to its implications for thrombotic risk.
  • D) Vitamin C deficiency (Scurvy): While vitamin C deficiency can cause bleeding gums and other bleeding issues due to its role in collagen synthesis and thus vessel wall integrity, it would not typically cause the specific coagulation abnormalities seen here, such as low factor VIII levels.

• Rare diagnoses

  • Other rare bleeding disorders, such as factor XI deficiency or afibrinogenemia, could present with similar laboratory findings but would be less likely given the clinical context and family history provided. These conditions might be considered if the initial diagnoses are ruled out or if additional specific symptoms or laboratory findings suggest them.