Patient case (clinical description): A 23-year-old female has prolonged oral bleeding immediately after a tooth extraction.  Despite several interventions, the bleeding persists for hours and stops only after desmopressin (DDAVP) administration.  The patient has heavy menstrual cycles each month.  She has no other medical problems and takes no medications.  Her mother and grandmother have also had excessive bleeding during menstrual period.  Review of systems is positive for mild bruising on his legs. Laboratory findings reveal a normal platelet count and an abnormal ristocetin cofactor assay, as well as CB <= 0.30 IU/mL and FVIII:C <= 0.40 IU/mL.

Patient's own account: I'm a 23 woman and I went to the ER because of non-stop bleeding after my tooth extraction. I tried to make the bleeding stop but it just kept going for hours and it finally stopped when I took some medication called DDAVP. I usually have heavy periods, just like my mom and grandma had. I don't have any other medical condition and I don't take any other medication. The doctor noticed the bruises on my legs. I had to do some lab tests. I had a normal platelet count but an abnormal ristocetin cofactor assay. I had low CB and FVIII:C levels.

Clinical trial: DDAVP vs. Exercise in Patients With Mild Hemophilia A

Eligibility criteria:
Inclusion Criteria:

          -  Patients ≥13 years of age and ≤21 years of age with Mild Hemophilia A (MHA), with a
             historical baseline FVIII:C level of ≥5% to ≤40% followed at either the Hospital for
             Sick Children or St. Michael's Hospital (Toronto).

          -  Patients ≥13 years of age and ≤21 years of age with genetically confirmed Mild
             Hemophilia A (MHA), with FVIII:C level of ≥5% to ≤50% followed at either the Hospital
             for Sick Children or St. Michael's Hospital (Toronto).

        Exclusion Criteria:

          -  A currently circulating or history of a previous inhibitor ( ≥0.5 BU) within the past
             5 years. As inhibitor development in MHA is rare, it is not expected that any patient
             will be excluded for this reason.

          -  Any FVIII infusion or DDAVP use in the preceding week. This is to avoid an residual
             FVIII still being present in a patient who has taken an extended half-life FVIII.

          -  Co-existence of a congenital bleeding disorder other than MHA (e.g. VWD).

          -  Prior history of coronary artery disease or pulmonary disease, severe arthropathy
             interfering with ability to exercise.

          -  Patients on beta-blockers, anti-platelet agents or regular non-steroidal
             anti-inflammatory medications (e.g. Celebrex).

          -  Patients with an active infectious or inflammatory condition. This includes HIV,
             active hepatitis B or C as reflected in elevated AST, ALT, RNA positivity for
             hepatitis B or C.

          -  Patients who are active (defined as smoking daily) smokers (cigarettes, marijuana).
             This exclusion is put into place as we do not know if daily smoking will impact on the
             hemostatic response to either exercise or DDAVP.

          -  Patients with limited exercise tolerance for any reason.

          -  Patients with a history of a recent bleed (in preceding 2 weeks) in any location, or a
             joint/muscle bleed in the lower limbs in the preceding 4 weeks.

          -  Patients who for medical reasons should not receive DDAVP [those with renal or CNS
             disease (e.g. brain tumor)] or have previously experienced adverse events with DDAVP
             (e.g. hypotensive event; seizure).
Male
No healthy subjects accepted to join the trial.
Subject must be at least 13 Years old.
Subject must be at most 21 Years

Eligibility (NLI label): Contradiction