Rare Bleeding Disorders
Factor XII (Hageman factor) deficiency
is a rare inherited disorder that affects a special protein that helps in the clotting process. A lack of factor XII does not cause abnormal bleeding, and there are usually no noticeable symptoms. For this reason, factor XII deficiency is usually found only as a byproduct of routine blood testing, as the blood takes longer to clot in a test tube.1
Factor XII deficiency is sometimes classified as having no clinical significance, and treatment is usually not needed. The outlook is usually good and there are usually no complications.1
- Factor XII (Hageman factor) deficiency. MedlinePlus website. http://www.nlm.nih.gov/medlineplus/ency/article/000545.htm. Accessed December 17, 2014.