Coagulation Case Studies

Little girl with multiple problems, has a PT and APTT performed-
PT= 32 seconds
APTT =76 seconds
1:1 mix= PT= 12.1
APTT = 32.1 seconds correct into normal range
Factor deficiency?
Common pathway: II, V, and X all normal
VIII, IX, XI and XII all normal

What do these results mean?

ANSWERS TO CASE STUDIES:

We know the disorder is in the common pathway-
and that it is a factor deficiency. Both the PT and APTT correct into the normal range-
large correction- this little girl has a fibrinogen deficiency.
A thrombin time should also be performed should be prolonged-
A reptilase time will be prolonged, this will confirm no heparin on board and truly a fibrinogen deficiency.
Also, if there was heparin on board the mixing study would not correct (remember heparin is an inhibitor)
The next step is to see if this is due to a quantitative or qualitative defect of fibrinogen. If antigen testing is normal and activity is abnormal this is a dsyfunctional molecule or a qualitative defect. If both are decreased there would be a quantitative defect.
The FDA just approved treatment with fibrinogen concentrates, prior to that the treatment was cryoprecipitate.