Patient case (clinical description): A 20-year-old man comes to the emergency due to bleeding after a tooth extraction.  The bleeding has persisted for approximately 30 minutes despite constant direct pressure.  He is a known case of Hemophilia type A treated with FVIII. Blood pressure is 95/60 mm Hg and pulse is 105/min. His weight is 70 Kg. Family history is positive for Hemophilia type A in his maternal uncle. He also has a lipoma on his left arm which he plans to remove surgically. His FVIII activity is 40%.

Patient's own account: I got my tooth extracted and I could not stop bleeding for 30 min. I'm a 20 yo dude but I have Hemophilia type A treated with FVIII. My blood pressure was 95/60 and my pulse 105/min. I'm 70 kg. My uncle on my mom's side also has type A hemophilia. I also have a fatty swelling on my left arm and I was supposed to remove it. My FVIII activity was 40%.

Clinical trial: Acquired Hemophilia A and Autoimmunity. Study of Lymphocyte Populations and Myeloid-Derived Suppressor Cells

Eligibility criteria:
Inclusion Criteria:

          1. Patient population with acquired hemophilia A:

             Adult patients with a diagnosis of acquired hemophilia A and with a social security
             system. Obtaining oral non-opposition from the patient to participate in the study
             following the submission of an information note relating to the project.

             Obtaining signed and written informed consent for biocollection consent.

          2. Population of Patients with constitutional hemophilia A:

             Adult patients over 50 years of age with severe or moderate constitutional hemophilia
             A, with no history of autoimmune disease, and with a social security system.

             Obtaining oral non-opposition from the patient to participate in the study following
             the submission of an information note relating to the project.

             Obtaining signed and written informed consent for biocollection consent.

          3. Population of control subjects:

             Adult patients, over the age of 60, without a coagulation abnormality, with no history
             of autoimmune disease, and with a social security system.

             Obtaining oral non-opposition from the patient to participate in the study following
             the submission of an information note relating to the project.

             Obtaining signed and written informed consent for biocollection consent.

          4. Patient population with inflammatory pathology:

        Adult patients over the age of 50 with an inflammatory pathology likely to be associated
        with acquired hemophilia A, and with a social security system.

        Obtaining oral non-opposition from the patient to participate in the study following the
        submission of an information note relating to the project.

        Obtaining signed and written informed consent for biocollection consent.

        Exclusion Criteria:

        For the 4 groups:

          -  Minor patient, under guardianship or curatorship.

          -  Pregnant and lactating women.

          -  Blood transfusion less than 7 days old.

          -  Treatment with corticosteroids in the 7 days preceding inclusion or any other
             immunomodulatory or immunosuppressive treatment in the 4 weeks preceding inclusion.
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 18 Years old.


Eligibility (NLI label): Contradiction