What laboratory tests should be ordered for a young adult with frequent epistaxis (nosebleeds)?

From the Guidelines

For a young adult with frequent nosebleeds, I recommend checking complete blood count (CBC), coagulation studies (PT/INR, PTT), and platelet function tests, as well as von Willebrand factor assay to rule out von Willebrand disease, which is the most common inherited bleeding disorder, as suggested by the most recent guidelines 1.

The CBC will assess for anemia and platelet count abnormalities, while coagulation studies evaluate the clotting cascade. Additional tests, such as von Willebrand factor assay, are essential to rule out underlying bleeding disorders. If there's a family history of bleeding disorders, factor assays (particularly for factors VIII and IX) may be appropriate. Liver function tests are also valuable since liver disease can impair clotting factor production. A basic metabolic panel can help identify kidney dysfunction that might contribute to bleeding tendencies.

These tests are essential because frequent nosebleeds in young adults may indicate an underlying hematologic disorder rather than just local nasal issues. While local causes like nasal dryness or trauma are common, persistent or severe epistaxis warrants laboratory evaluation to exclude systemic causes that could lead to more serious bleeding complications if left undiagnosed. The initial laboratory evaluation should include the "initial hemostasis tests" as suggested by the NHLBI VWD Guidelines, which include a complete blood count (CBC), prothrombin time (PT), and activated partial thromboplastin time (PTT) 1.

Key laboratory tests to order include:

• Complete blood count (CBC)
• Coagulation studies (PT/INR, PTT)
• Platelet function tests
• Von Willebrand factor assay
• Liver function tests
• Basic metabolic panel

It is crucial to note that the management of nosebleeds should be individualized, and the choice of laboratory tests may vary depending on the patient's clinical presentation and medical history. However, the above-mentioned tests provide a comprehensive initial evaluation for underlying bleeding disorders and systemic causes of epistaxis.

From the Research

Laboratory Tests for Epistaxis

To determine the appropriate laboratory tests for a young adult with frequent epistaxis, several factors should be considered, including clinical assessment, pertinent history, and family history 2. The following tests may be ordered:

• Complete blood cell count (CBC) to evaluate for anemia, thrombocytopenia, or other abnormalities 2, 3
• Platelet count to assess for thrombocytopenia or platelet function disorders 2, 4
• Prothrombin time (PT) and activated partial thromboplastin time (APTT) to evaluate coagulation pathways 2, 4, 5
• Evaluation of a peripheral blood sample to assess for morphological abnormalities 2

Specific Conditions to Consider

Certain conditions may be suspected based on laboratory results and clinical presentation, including:

• Von Willebrand disease, which may be suspected with a prolonged APTT and low levels of factor VIII 2, 6, 4
• Thrombocytopenia, which may result from idiopathic thrombocytopenic purpura, disseminated intravascular coagulation, or other conditions 2, 4
• Platelet function disorders, which may be suspected with a normal platelet count but abnormal bleeding history 6, 4

Indications for Coagulation Studies

Coagulation studies may be justified in certain situations, including:

• Patients with a known coagulopathy or chronic liver disease 5
• Patients receiving anticoagulant treatment 5
• Patients with a family history of bleeding disorders 4
• Patients with recurrent or severe epistaxis despite medical therapy 6