Related Experiment Video
Updated: Jul 5, 2025

Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice
Published on: September 30, 2021
Acquired Hemophilia A After Multiple Transfusions Following Trauma
Krisha G Hidalgo1,2, Danielle Z Azani2, Robert Fincher3
1Clinical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, USA.
Abstract:
Acquired hemophilia A (AHA) is a coagulative disorder that is caused by the presence of inhibitors of factor VIII (FVIII). The presence of coagulation factor inhibitors can lead to severe episodes of bleeding in patients with no previous history of bleeding conditions. We present the clinical case of a man with severe bleeding two weeks after falling from a bicycle. The patient denied any previous history of bleeding disorders. The case clinically presented with a large retroperitoneal hematoma and continued to show signs of active bleeding even after multiple transfusions were administered. Coagulation studies showed an elevated inhibitor titer of 24.4 BU/mL (normal range is below 5 BU/mL) and a reduced FVIII activity level of 2% (normal range is between 50% to 150%), providing evidence of AHA. Hemostatic and immunosuppressive agents were then administered to the patient, whose condition improved in response to the treatments.
Related Concept Videos
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Blood Transfusion and Agglutination
History
The history of blood transfusion dates back to the 17th century, when early attempts were made in animals. In 1818 James Blundell, a British doctor, performed the first successful human blood transfusion. Later in 1900, Karl...
Introduction to Hemostasis
The three phases of hemostasis involve many clotting factors present in plasma and several substances released by platelets and injured tissue cells. It is a fast, localized,...
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
Blood Transfusion
Blood Transfusion Overview
A blood transfusion is a medical procedure used to replace blood lost due to injury, surgery, or to treat conditions such as anemia or cancer. During a transfusion, donor blood is...
Anticoagulant Drugs: Low-Molecular-Weight Heparins

