Factor XIII Deficiency

Factor XIII deficiency is the rarest of factor deficiencies, with an estimated incidence of 1 in 5 million births. It is inherited in an autosomal recessive fashion, which means it is equally likely to affect men and women. The deficiency affects no specific racial or ethnic group.

Factor XIII is the protein responsible for stabilizing the formation of a blood clot. In the absence of factor XIII, a clot will still develop, but it will be unstable. When someone has factor XIII deficiency, the unstable clot will eventually break down, so recurrent bleeds are common. The prolonged bleeding seen in factor XIII deficiency is usually associated with trauma.

Patients with a severe form of factor XIII deficiency have a high risk of head bleeds with or without trauma. Bleeding immediately after surgery is usually not excessive but can be delayed. Pregnant women who go untreated face a risk of spontaneous abortion. Men with the deficiency may show signs of infertility. Common signs of the deficiency include soft tissue bleeds, menorrhagia, joint bleeding and persistent bleeding during circumcision or at the site of the umbilical cord.

Diagnosis is made by normal coagulation screening tests and a detailed family history. Specific factor XIII assays can be employed to confirm the diagnosis. The condition can also be defined by a clot solubility test.

Treatment

There are currently two commercially produced factor XIII concentrates produced in Europe. One is manufactured by Bio Products Laboratory (BPL) and is only available in the United Kingdom. The other product is manufactured by CSL Behring GMBH in Germany. It is only available under IND or through clinical trial in the United States. Neither product is approved for use in the United States. The current treatments for factor XIII deficiency in the United States is cryoprecipitate or fresh-frozen plasma.