Coagulation factor XIII

General Information

Coagulation factor XIII or fibrin stabilizing factor is a tetrameric molecule that is synthesized in hepatocytes and megakaryocytes. It is activated by thrombin in the presence of calcium ions (XIIIa – activated factor XIII).

Functionally, factor FXIIIa is a transglutaminase that forms cross-links between fibrin monomers. This increases the stability of the formed clot to fibrinolytic activity. Also, factor XIIIa promotes the proliferation of fibroblasts and the processes of restoring the damaged endothelium of blood vessels. It is necessary to maintain pregnancy.

Genetic deficiency of factor XIII is transmitted in an autosomal recessive manner and is quite rare in the population. Deficiency of factor 13 is suspected when significant bleeding occurs despite normal values ​​of activated partial thromboplastin time (APTT) and thrombin time.

Heterogeneous (having only 1 copy of the abnormal gene) individuals have no symptoms. In homozygotes (having 2 copies of the pathological gene), the clinical picture of bleeding is always revealed:

• Bruises at the level of the navel
• Ecchymoses and hemorrhages in the skin and mucous membranes
• Intracranial hemorrhage as a result of minor trauma

Bleeding or bruising usually develops a little later, 12-36 hours after the injury. Post-operative wounds are usually complicated by bleeding, wound healing processes are prolonged, and pathological scars are formed. Spontaneous lethal intracerebral hemorrhages have also been described in such patients.

In homozygous individuals, spontaneous abortions in women and infertility in men are also common.

Treatment of hemorrhagic processes includes control of FXIII and cryoprecipitate. Thanks to the long half-life of factor 13, prophylactic treatment can be administered in 2-6 weeks.

Acquired deficiency of factor 13 may occur in the following conditions: multiple myeloma, chronic lead poisoning, sickle cell anemia, vasculitis, burns, Henoch's purpura (an autoimmune disease), acute leukemia, polycythemia vera (a tumor of the hematopoietic system in which red blood cells are produced excessively), radiotherapy , liver diseases, inflammatory bowel disease, kidney diseases, neoplasms. The formation of autoantibodies to factor 13 may occur when taking such drugs as: ozoniazid, penicillin, phenytoin.

Preliminary preparation: The study is conducted on an empty stomach.

Material for examination: Venous blood.

Reference norms: 70-130%