Hemophilia B
Hemophilia B is a hereditary disease with a disturbed blood coagulation caused by the lack of the coagulation factor IX (also called Christmas factor).
Because hemophilia is an X-linked recessive mutation, the disease mainly affects men. Patients suffer from repeated and hardly stoppable, external and internal bleeding, which in the worst case, ends fatally.
In particular, joint bleeding, muscle bleeding, and spontaneous subcutaneous hematomas occur. Depending on the severity of the lacking coagulation factors, the course of the disease varies greatly.