Disorder - Factor XII deficiency

Organ Systems Involved
Cardiovascular

Alternative disorders described within LIDA

Factor VIII deficiency (Haemophilia A); Factor IX deficiency (Haemophilia B); Factor X deficiency; Factor XI deficiency (Haemophilia C); Contact activation defect

Alternative Names
Hageman trait; Hageman factor deficiency

Presenting Signs

The normal clotting of blood is the result of a complex train, or cascade of reactions. This involves platelets (tiny blood cells responsible for clotting) and various proteins. When there is bleeding, the clotting cascade is activated and leads to the formation of a plug to fill the hole in the blood vessel wall. Factor XII is a protein that is important in the clotting cascade. In other clotting factor deficiencies, the cat will present with excessive bleeding and bruising following relatively minor injuries. Factor XII deficiency, however, does not lead to excessive haemorrhage, as long as there enough of the other clotting factors to compensate. In fact in cats, the deficiency of factor XII is often found coincidentally when routine clotting tests are carried out. It typically causes no clinical signs. Affected cats can live normally and never show any signs of a bleeding disorder.

Cats at Risk

Female cats are more likely to be affected than males. It is inherited as a recessive trait that can be either fully expressed (homozygous) or partially expressed (heterozygous).

Treatment

None or medical: treatment is generally not required, since this deficiency is typically not associated with any clinical signs. Short term treatment may be possible with a blood transfusion.

PubMed References
Factor XII deficiency

Contributor
Sarah Michael