A 4-year-old boy presents with intermittent epistaxis for 2 years, with approximately 3 to 4 episodes per month, each lasting for between 20 to 30 minutes. His mother states that he has had mild bruising following vaccination in the past, and that she has occasionally observed bruises in his extremities, which she attributed to his being an active child. His surgical history is significant for prolonged postoperative bleeding following a tonsillectomy. He has never been transfused with blood or blood products. His family history is negative for bleeding disorders, and he has a healthy sister who is 10 years old. His birth and developmental histories are unremarkable. A liver profile, renal profile, serum electrolyte assay, and erythrocyte sedimentation rate are found to be within normal parameters.