Snapshot A 3-year-old boy is seen at his annual pediatrician’s visit with a concern for prolonged nosebleeds. Ever since he was about 2 years old, he has had multiple episodes of nosebleeds that stopped only after hours. On physical exam, his right elbow is slightly swollen and tender to palpation. On further question, there is a family history of unexplained bleeding in the patient’s maternal uncle. Lab results reveal increased PTT that corrects after mixing studies. Introduction Hereditary deficiencies in coagulation factors Hemophilia A and B are clinically indistinguishable Think HIV in older hemophiliacs due to lack of blood screening for HIV with given transfusions Epidemiology Almost exclusively in males Genetics login to view 1 more bullet etiology Pathogenesis login to view 6 more bullets Presentation Symptoms are similar in both hemophilia A and B login to view 5 more bullets Physical exam login to view 2 more bullets studies ↑ PTT login to view 4 more bullets normal PT normal bleeding time most specific test login to view 1 more bullet Differential Diagnosis DIC von Willebrand disease Platelet function disorders Treatment Prevention login to view 1 more bullet For mild cases login to view 2 more bullets Severe cases login to view 1 more bullet Complications Musculoskeletal complications login to view 3 more bullets Prognosis Normal mortality