Step I Hematology - DIC Question

[docjohn101]

DIC: Why are Factors V and VIII low?

 

[shan564]

All of the factors are low because they're getting used up so quickly. I think we particularly look at V and VIII just because we commonly test for those two.

 

[alternatego]

From what I could find in Goljan's RR p. 261, its because fibrin thrombi consume factors I, II, V and VIII when they form in the microcirculation.

 

[Phloston]

Wait, Shan, I think docjohn is onto something. I remember having heard somewhere that factors V and VIII are unique in that they're not serine-proteases. Antithrombin-III normally inhibits the serine-proteases efficaciously, but we need proteins C (and S, Z) to inactivate V and VIII particularly.

(I'm not 100% about that, but could someone else help out here....)

 

[RedSoxSuck]

Wait, Shan, I think docjohn is onto something. I remember having heard somewhere that factors V and VIII are unique in that they're not serine-proteases. Antithrombin-III normally inhibits the serine-proteases efficaciously, but we need proteins C (and S, Z) to inactivate V and VIII particularly.

(I'm not 100% about that, but could someone else help out here....)

Protein C and S are needed to inactivate factor 5 and 8.

I feel smart just by commenting on Phloston's post. lol

 

[Morsetlis]

Wait, Shan, I think docjohn is onto something. I remember having heard somewhere that factors V and VIII are unique in that they're not serine-proteases. Antithrombin-III normally inhibits the serine-proteases efficaciously, but we need proteins C (and S, Z) to inactivate V and VIII particularly.

(I'm not 100% about that, but could someone else help out here....)

Omg how do you know these things.

 

[Phloston]

DIC: Why are Factors V and VIII low?

Today was a good push. I managed to get 225 questions done from FA Q&A.

Anyway, one of them was on DIC, and it actually said in the explanation that Proteins C & S are consumed rapidly (as well as fibrinogen [when it goes to fibrin]); that explains why factors V and VIII would be low, given that they're specifically regenerated by proteins C/S.