Hemophilia A vs von Willebrand disease?

[Dr.NickRiviera]

increased PTT and bleeding time
aggregation of platelets with ristocetin absent
factor VIII decreased

with these findings, how do I differentiate between hemophilia A and vW disease?

[haga]

factor 8 by itself is purely a coagulation factor, so its deficiency will only affect the intrinsic pathway.

vWd is a combined platelet and coagulation factor deficiency as it is the carrier for factor 8. It's deficiency will affect platelet function AND the intrinsic pathway.


Since we know that BT is increased there is a platelet defect. Since PTT is increased there is a coagulation defect. Since aggregation of platelets is defective we know that vWF is missing since it initiates the aggregation process.

Combined platelet (increased bleeding time) and coagulation factor (increased PTT) coupled with aggregation problem can only mean vWD.


If it had said that only PTT was increased with a decrease in factor 8 then you know its Hemophilia A.

[haga]

The basic concept here is that if the BT is increased then it HAS to be something that causes a platelet defect even if the PT or PTT are increased.

Coagulation defects alone will ONLY affect PT or PTT without any affect on BT.

If you get the chance you should listen to Goljan's audio lectures. He is amazing at clearing concepts. If you need the link to download them let me know.

[Dr.NickRiviera]

Originally Posted by haga

The basic concept here is that if the BT is increased then it HAS to be something that causes a platelet defect even if the PT or PTT are increased.

Coagulation defects alone will ONLY affect PT or PTT without any affect on BT.

If you get the chance you should listen to Goljan's audio lectures. He is amazing at clearing concepts. If you need the link to download them let me know.

awesome, thats what i thought but wasnt sure
thanks alot!

[Master shifu]

Originally Posted by haga

The basic concept here is that if the BT is increased then it HAS to be something that causes a platelet defect even if the PT or PTT are increased.

Coagulation defects alone will ONLY affect PT or PTT without any affect on BT.

If you get the chance you should listen to Goljan's audio lectures. He is amazing at clearing concepts. If you need the link to download them let me know.

Hey....Bosss.....you have mentioned in your post about link of Goljan audio lecture.........Is it for free download....If then please send me through PM if you like to send................i would be thankful to you

[roshan dinparast]

in addition to comprehensive answers above, the clinical manifestation also differs in Hemophillia and VW disease.in hemophilia patient has deep tissue bleeding(hemarthrosis), but in VW disease, the patient has menorrhagia,or other forms of mucosal bleeding(GI bleeding, Hematuria,...)