Antithrombin abnormalities and perinatal management.
Review published in Current drug targets (2005)
Abstract
Antithrombin (AT) is an important regulator of the coagulation cascade because of its ability to efficiently inhibit proteases such as Factor (F) Xa and thrombin. Type I hereditary AT deficiency is characterized by a quantitative deficiency in the antigen and activity of AT to about 50% of normal. Type II hereditary AT deficiency is characterized by a normal antigenic level of AT, with a low level of activity due to a dysfunctional protein. Impaired synthesis, consumptive coagulopathy including pregnancy-induced AT deficiency in multiple pregnancies, and urinary protein loss are associated with acquired AT deficiencies. Inherited thrombophilias are the leading cause of maternal thromboembolism and are associated with increased risk of second- and third-trimester fetal loss, abruptions, severe intrauterine growth restriction, and early-onset severe preeclampsia. Among thrombophilias, AT deficiency has long been associated with a significant thrombotic tendency throughout gestation and the puerperium. Treatment for this disorder includes antithrombotic therapy with unfractionated heparin or low molecular weight heparin, followed by an oral vitamin K antagonist, such as warfarin. Some patients with very low AT levels may be resistant to heparin therapy and may require increased doses of heparin or AT concentrates. In addition, an acquired decrease of AT plasma levels is a common finding in patients with preeclampsia. It is suggested that the administration of AT concentrates improves uteroplacental circulation and influence the pathophysiology of preeclampsia. Furthermore, it has been demonstrated that hereditary AT deficiency is associated with fetal loss. In women with a severe thrombotic tendency and recurrent fetal loss, thromboprophylaxis may offer more benefits.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Resumen
Antithrombin (AT) is an important regulator of the coagulation cascade because of its ability to efficiently inhibit proteases such as Factor (F) Xa and thrombin. Type I hereditary AT deficiency is characterized by a quantitative deficiency in the antigen and activity of AT to about 50% of normal.
Por qué esto importa para la hirudoterapia
Esta revisión examina las deficiencias hereditarias y adquiridas de antitrombina (AT), centrándose en su asociación con tromboembolismo materno, pérdida fetal y preeclampsia durante el embarazo y el período perinatal. Discute estrategias de manejo clínico que involucran heparina no fraccionada, heparinas de bajo peso molecular, antagonistas orales de la vitamina K y concentrados de AT para tratar estos trastornos trombofílicos graves. Si bien comprender los anticoagulantes fisiológicos como la antitrombina es valioso para el campo más amplio de la trombosis y la hemostasia, este artículo no tiene un vínculo directo con la hirudoterapia. El resumen se centra por completo en la medicina maternofetal humana y el manejo farmacológico estándar, sin ninguna mención de sanguijuelas, hirudina o terapias derivadas de sanguijuela.
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Añadido a la biblioteca ASH: May 28, 2026 · Última actualización del sitio: 18 de junio de 2026