Soru

An outpatient evaluation is conducted for a 26-year-old female who reports a lifelong history of recurrent epistaxis and menorrhagia. Her menstrual periods typically last $8$ to $10$ days and require changing a highly absorbent pad every $2$ hours. One month ago, she required suturing and localized thrombin application for persistent oozing following a routine dental extraction. The patient takes an oral contraceptive pill and an over-the-counter iron supplement. Family history is notable for a mother who underwent a hysterectomy at age $40$ for heavy uterine bleeding.

Vital signs are normal. Physical examination reveals scattered, small ecchymoses on the shins but is otherwise unremarkable; there are no petechiae or joint effusions.

Initial laboratory studies reveal:
Complete blood count:
Hemoglobin: $10.8 \text{ g/dL}$
Mean corpuscular volume: $76 \text{ fL}$
Platelet count: $285,000 /\mu\text{L}$

Coagulation profile:
Prothrombin time (PT): $12.5 \text{ seconds}$ (Reference: $11-15 \text{ seconds}$)
Activated partial thromboplastin time (aPTT): $52 \text{ seconds}$ (Reference: $25-40 \text{ seconds}$)
aPTT mixing study (1:1 with normal plasma): $31 \text{ seconds}$

Further hemostatic testing:
Platelet Function Analyzer (PFA-100) closure times:
Collagen/Epinephrine: $185 \text{ seconds}$ (Reference: $84-160 \text{ seconds}$)
Collagen/ADP: $142 \text{ seconds}$ (Reference: $68-121 \text{ seconds}$)
Factor VIII activity: $35\%$ (Reference: $50-150\%$)

Based on the interpretation of these laboratory findings, which of the following is the most likely diagnosis?