Bleeding Disorders

Question 1

Von willebrand disease

Answer 1

• most common bleeding disorder
• autosomal dominant disorder
• clinical findings: mild to moderate bleeding, nosebleeds, heavy menstruation, gingival bleeding, easy bruising
• vWF adheres platelets and acts as carrier for factor 8 resulting in low factor 8
• diagnosis: prolonged bleeding time and a normal or prolonged aPTT, vWF antigen level, vWF activity assay, factor 8 level, multimer study
• treatment: DDAVP for mild to moderate bleeding or before minor procedures, DO NOT use cryoprecipitate due to increased transfusion infection risk

Question 2

Lab findings in common bleeding disorders

Answer 2

• increased PT and aPTT: clotting factor deficiency
• increased PT and normal aPTT: factor VII def
• normal PT and increased aPTT that corrects mixing studies: factor def(VIII, IX, XI, or XII), UFH, factor more likely if no evidence of bleeding