Tranexamic Acid for Congenital Afibrinogenemia
Tranexamic acid (TXA) can be used in patients with congenital afibrinogenemia, particularly as an adjunct therapy to fibrinogen replacement during bleeding episodes, surgical procedures, or postpartum management. 1
Mechanism and Rationale
- TXA is a synthetic lysine analogue that competitively inhibits plasmin and plasminogen, preventing fibrin degradation and stabilizing clots 2
- In afibrinogenemia, the primary treatment is fibrinogen replacement, but TXA can provide additional hemostatic support by preventing breakdown of the formed clots 1
- The plasma half-life of TXA is approximately 120 minutes, requiring multiple daily doses or continuous infusion to maintain therapeutic levels 2
Recommended Dosing for Afibrinogenemia
- For acute bleeding episodes: TXA 10-15 mg/kg followed by an infusion of 1-5 mg/kg per hour 1
- For surgical procedures: TXA can be administered prophylactically at the time of delivery or surgery in patients with a bleeding phenotype 1
- For pregnancy loss management: TXA is recommended in conjunction with fibrinogen replacement targeting levels ≥1.5 g/L for 3 days 1
Clinical Scenarios for TXA Use in Afibrinogenemia
Pregnancy and Delivery
- TXA is specifically recommended for women with afibrinogenemia during delivery to reduce bleeding risk 1
- For postpartum hemorrhage prevention: TXA may be considered to prevent secondary postpartum hemorrhage and prolonged or heavy lochia 1
- For pregnancy loss: Surgical management with fibrinogen replacement and TXA is recommended to avoid excessive bleeding 1
Surgical Procedures
- TXA should be used as prophylaxis at the time of surgery in patients with afibrinogenemia who have a bleeding phenotype 1
- Fibrinogen replacement remains the primary therapy, with TXA serving as an adjunctive treatment 1
Important Considerations and Precautions
- TXA should always be used in conjunction with fibrinogen replacement in afibrinogenemia, not as monotherapy 1
- Target fibrinogen levels should be ≥1.5 g/L during acute bleeding episodes or surgical procedures 1
- The thrombotic risk must be carefully assessed before administering TXA, particularly in patients with a history of thrombosis 1, 3
- In patients receiving fibrinogen replacement who have additional thrombotic risk factors, the concurrent use of thromboprophylaxis with low molecular weight heparin may be necessary 1
Monitoring and Duration of Therapy
- TXA therapy should be stopped once bleeding has been adequately controlled 1
- Regular monitoring of fibrinogen levels is essential throughout treatment 1
- For surgical procedures, TXA can be continued for 3-5 days postoperatively, depending on the bleeding risk 1
Special Populations
- In pediatric patients with afibrinogenemia, TXA dosing should be adjusted based on weight 1
- In pregnant women with afibrinogenemia, TXA use depends on the thrombotic risk profile 1
TXA represents a valuable adjunctive therapy in the management of congenital afibrinogenemia, particularly during high-risk bleeding episodes, surgical procedures, and obstetric complications. However, it should always be used in conjunction with appropriate fibrinogen replacement therapy to achieve optimal hemostasis 1.