Lesión pulmonar aguda como consecuencia de la transfusión de plasma fresco congelado en un paciente con déficit de factor XII / Acute lung injury as a consequence of fresh frozen plasma administration in a patient with factor XII deficiency

Los test de coagulación son, junto con el hemograma, las pruebas de laboratorio más solicitadas a los pacientes antes de una intervención quirúrgica. El tiempo de tromboplastina parcial activado (TTPA) cuantifica la vía intrínseca y común de la coagulación, incluyendo los factores XII, XI, IX, VIII, X, V y II. El déficit de factor XII se asocia a un alargamiento del TTPA y a un aumento de los fenómenos tromboembólicos sin incrementar el riesgo de hemorragia intraoperatoria. A un varón de 20 años con déficit de factor XII se le administraron dos unidades de plasma fresco congelado ante un valor de TTPA de 100 segundos con intención de corregir una posible alteración de la coagulación ante una cirugía de urgencias y el temor de un sangrado intraoperatorio. A la hora del inicio de la trasfusión el paciente desarrolló un cuadro de lesión pulmonar aguda compatible con el diagnóstico de TRALI (transfusión related acute lung injury). La cirugía trascurrió con normalidad y el paciente permaneció ingresado en la unidad de reanimación 72 horas durante las que precisó soporte respiratorio. Ante una prolongación del TTPA en ausencia de sangrado se debe descartar la presencia de un anticoagulante circulante inespecífico, un déficit de factor XI, un déficit de factor XII y un déficit de factor VIII asociado a la enfermedad de von Willebrand. Por lo tanto, en el caso que presentamos fue innecesaria la administración de hemoderivados al paciente pudiendo tener consecuencias tan graves como la que presentó, la aparición de una lesión pulmonar aguda asociada a la trasfusión (AU)

Along with the complete blood count, the coagulation tests are those most demanded before a surgical procedure. The activated partial thromboplastin time (APPT) quantifies the intrinsic and common coagulation pathways, including factors XII, XI, IX, VIII, X, V and II. Factor XII deficiency is associated with a prolonged APPT and an increase in thromboembolic phenomena, without increasing the intraoperative bleeding risk. A 20 year old man with factor XII deficiency was receiving two units of fresh frozen plasma because of an APPT of 100 seconds, with the intention of normalizing it before an urgent surgery procedure, and the fear of intraoperative bleeding. An hour after starting the transfusion the patient developed an acute lung injury (ALI) compatible with the diagnosis of a transfusion related acute lung injury (TRALI). The surgery continued without complications, and the patient was admitted to the resuscitation unit for 72h, needing respiratory support. If the APTT is prolonged in the absence of bleeding, the presence of a non-specific circulating anticoagulant, a deficiency of factor XI, XII and VIII (associated to Von Willebrand disease) must be ruled out. Therefore, in the case presented here, the administration of hemoderivatives was unnecessary and can have consequences as serious as the one that the patient presented, a transfusion related acute lung injury (AU)

Pronóstico materno y perinatal en el embarazo con deficiencia del factor XII / Maternal and perinatal prognosis in pregnancy with factor XII deficiency

ANTECEDENTES: El déficit de factor XII es una enfermedad poco frecuente, relacionada con trombosis y abortos a repetición. OBJETIVO: Evaluar el resultado materno y perinatal en 25 embarazadas con déficit del factor XII. MÉTODOS: Estudio observacional descriptivo de 25 embarazadas (27 gestaciones) con esta patología desde enero 2005 a junio de 2011. RESULTADOS: La asociación de alteración del factor XII con otras trombofilias hereditarias o adquiridas es frecuente. En 24 mujeres se obtuvieron gestaciones exitosas, con sólo 3 abortos. Hubo 20 partos a término, con recién nacidos con peso y Apgar adecuado. Se registró un caso de restricción de crecimiento intrauterino. No hubo complicaciones médicas. Se utilizaron en todas las embarazadas antiagregantes y/o antitrombóticos como tratamiento. El fármaco utilizado más frecuente fue la heparina de bajo peso molecular, asociada en ocasiones al ácido acetilsalicílico. No hubo complicaciones por el uso de heparina de bajo peso molecular. CONCLUSIONES: El control multidisciplinar del embarazo y el tratamiento individualizado ha conseguido en esta patología buenos resultados maternos y neonatales.

BACKGROUND: The factor XII deficiency is a rare disease related with thrombosis and recurrent pregnancy loss. OBJECTIVE: To evaluate maternal and perinatal outcome in 25 pregnant women with deficiency of factor XII. METHODS: An observational descriptive study of 25 women with factor XII deficiency and pregnancy (27 pregnancies) between January 2005 and March 2011. RESULTS: The association with other inherited or acquired thrombophilia is common. 24 women have achieved successful pregnancies and only 3 miscarriages. There were 20 women with deliveries at term, with appropiate birth weight and Apgar test. There was one case of intrauterine growth restriction. There were no medical complications. The treatment used was antiplatelet and/or antithrombotic agents in all cases. The most used drug was low molecular weight heparin, sometimes associated to acetylsalicylic acid. CONCLUSIONS: A multidisciplinary control of the pregnancy and an individualized treatment has achieved good maternal and neonatal outcomes.

Factor XI and XII as antithrombotic targets.

PURPOSE OF REVIEW: Arterial and venous thrombosis are major causes of morbidity and mortality, and the incidence of thromboembolic diseases increases as a population ages. Thrombi are formed by activated platelets and fibrin. The latter is a product of the plasma coagulation system. Currently available anticoagulants such as heparins, vitamin K antagonists and inhibitors of thrombin or factor Xa target enzymes of the coagulation cascade that are critical for fibrin formation. However, fibrin is also necessary for terminating blood loss at sites of vascular injury. As a result, anticoagulants currently in clinical use increase the risk of bleeding, partially offsetting the benefits of reduced thrombosis. This review focuses on new targets for anticoagulation that are associated with minimal or no therapy-associated increased bleeding. RECENT FINDINGS: Data from experimental models using mice and clinical studies of patients with hereditary deficiencies of coagulation factors XI or XII have shown that both of these clotting factors are important for thrombosis, while having minor or no apparent roles in processes that terminate blood loss (hemostasis). SUMMARY: Hereditary deficiency of factor XII (Hageman factor) or factor XI, plasma proteases that initiate the intrinsic pathway of coagulation, impairs thrombus formation and provides protection from vascular occlusive events, while having a minimal impact on hemostasis. As the factor XII-factor XI pathway contributes to thrombus formation to a greater extent than to normal hemostasis, pharmacological inhibition of these coagulation factors may offer the exciting possibility of anticoagulation therapies with minimal or no bleeding risk.

Factor XII deficiency and cardiopulmonary bypass.

Factor XII initiates the intrinsic coagulation cascade and may affect the fibrinolytic system. Routine coagulation tests used during cardiopulmonary bypass (CPB) are abnormal in factor-XII-deficient patients and are useless for monitoring anticoagulation in these patients. A factor-XII-deficient patient requiring CPB is described. The baseline celite activated clotting time (ACT) was greater than 1400 seconds and the thrombin time was 12.4 seconds (control, 11.9 seconds). Two units of plasma were given resulting in an ACT of 173 seconds. Following 300 units/kg of heparin and during CPB, the ACT ranged from 670-596 seconds with the thrombin time greater than 200 seconds. Plasma provides exogenous factor XII allowing an endpoint on the ACT test and may protect against possible postoperative hypofibrinolytic complications. A commercially available modified thrombin time may also be useful and provide an endpoint during high-dose heparinization.

[Recurrent venous thromboses in hypoplasia of the vena cava inferior and factor XII deficiency]. / Rezidivierende Venenthrombosen bei Vena-cava-inferior-Hypoplasie und Faktor-XII-Mangel.

The cause of recurrent pelvic and leg venous thromboses in a 24-year-old man was found to be a combination of two rare anomalies, hypoplasia of the hepatic, prerenal segment of the inferior vena cava and factor XII deficiency (factor XII activity 38%, its antigen 39% of normal), the latter considered a risk factor for thromboembolism. Subsequent fibrinolysis was not successful. No thromboembolic phenomena occurred during the following 16 months of oral anticoagulation with phenprocoumon. When this treatment was discontinued at the patient's behest, there was a recurrence on the contralateral side. Anticoagulation was resumed and has continued now for 1 1/2 years without recurrence. The patient has been largely free of symptoms. Permanent anticoagulation thus seems unavoidable in this case.