Clopidogrel-induced acquired haemophilia A in a post-TAVR patient: a case report and literature review.

Background: Acquired haemophilia A is a rare bleeding disorder characterized by spontaneous bleeding. Apart from diagnosing and treating it promptly, finding the causative factor for acquired haemophilia A, if any, is equally important. Case summary: In this case report, we discuss a 63-year-old female who underwent a recent transcatheter aortic valve replacement and presented to the emergency department with posterior thigh pain, where she was found to have a haematoma. She was ultimately diagnosed with acquired haemophilia A secondary to clopidogrel. In addition to discontinuing clopidogrel, the patient received immunosuppressive therapy, including cyclosporine, prednisone, intravenous immunoglobulins, rituximab, and recombinant factor VIIa. Discussion: Clopidogrel, one of the most commonly used medications in cardiology, is recognized as one of the leading drugs associated with acquired haemophilia A. In this case report, a review of the literature on ticagrelor and clopidogrel-induced acquired haemophilia A is also included, emphasizing the need for extreme vigilance in patients on antiplatelet therapy who present with unexplained bleeding.