Coagulation Case Studies

An 18 year old male has right knee arthroscopy with a diagnosis of hemarthrosis. His own history is insignificant for bleeding, no epistaxis, gum bleeding, non bleeding at circumcision. The family history -- father had a prolonged APTT pre-operatively in his 40's, treated with DDAVP and diagnosed with von Willebrand's disease, grandfather is in his 80's with no history of bleeding, half-sister has a strong history of menorrhagia but is negative for von Willebrand disease.

Physical examination reveals joint laxity.

Coagulation testing results as follows:
PT= 13.7 sec (10.5-13.0)
1:1 mix = 11.2 sec
Control = 11.0 sec
APTT= 33.9 sec (24.5-34.5)
Fibrinogen= 282 mg/dL (180-400)

Fac VII = 33% (50-150%)
Fac 8 = 99% (50-150%)
vWF activity = 59% (50-150%)
vWF antigen = 78% (50-150%)
PFA/ADP = 68 sec (56-128 sec)
PFA/EPI = 139 sec ( 74-186 sec)

• Does this patient have von Willebrand Disease?
• What is the most obvious diagnosis?
• What might be alternative diagnosis?
• What is the significance of joint laxity?
• What would be the final diagnosis and how would you treat this?