Acquired hemophilia

Acquired hemophilia (AH) is a rare autoimmune disorder characterized by bleeding that occurs in patients with a personal and family history negative for hemorrhages. Autoimmune disorders occur when the body’s immune system mistakenly attacks healthy cells or tissue. In AH, the body produces antibodies (known as inhibitors) that attack clotting factors, most often factor VIII. Clotting factors are specialized proteins required for the blood to clot normally. Consequently, affected individuals develop complications associated with abnormal, uncontrolled bleeding into the muscles, skin and soft tissue and during surgery or following trauma. Specific symptoms can include nosebleeds (epistaxis), bruising throughout the body, solid swellings of congealed blood (hematomas), blood in the urine (hematuria) and gastrointestinal or urogenital bleeding. AH can potentially cause severe, life-threatening bleeding complications in severe cases. In approximately 50% of patients, there is an identifiable underlying clinical condition; in the other 50% no cause is known (idiopathic).