FACTOR IX

Hemophilia B / Christmas disease (Factor IX deficiency) is a severe congenital X- linked bleeding disorder affecting 1:25,000 to 30,000 males. The disease is characterized by hemarthrosis, soft tissue hematomas, easy bruising, excessive bleeding during surgery, dental extraction and poor wound healing. Factor IX activity levels during childhood remain at about 75% of adult levels. There is a 25% increment in Factor IX expression that begins at puberty in both sexes.