A 24-year-old man presented to the hematology clinic for follow-up after a recent hospitalization for excessive bleeding from an accidental knife cut.

A 24-year-old man presented to the hematology clinic for follow-up after a recent hospitalization for excessive bleeding from an accidental knife cut. The patient reported a history of prolonged bleeding after tooth extraction, an upper gastrointestinal bleed 3 years previously, and excessive bruising since childhood. He denied hemarthroses but reported chronic pain in his ankles and joints. The patient reported having been treated with fresh frozen plasma (FFP) and factor VIII during past hospitalizations. The patient’s family history is noteworthy for a sister who also experienced excessive bleeding, although her diagnosis was uncertain. Initial laboratory test results included a normal complete blood count, including platelets, a prolonged activated partial thromboplastin time, and a prolonged prothrombin time. • Fibrinogen activity was normal. • Corrected Mixing Studies • Factor VIII:C Assay 5% • Factor IX Assay 38% • Factor IX Assay 88% What condition does the patient likely have? • Moderate Hemophilia B • VWD • Mild Hemophilia A • Moderate Hemophilia A