Hematology Flashcards
What does thrombin time test?
Assesses presence and function of fibrinogen
Factor XII deficiency
Elevated PTT, but no bleeding symptoms
Vit K factors
2, 7, 9, 10 and protein S/C
Timing of vit K def bleeding
Early = first 24hrs, classical = 2-7 days, Late = 1-6 months out
Shortest t1/2 factor
7
vWD type 1
Quantitative defect
vWD type 2A
Loss of large multimers
vWD type 2B
Gain of function, vWF too adherent to platelets
vWD type 2M
Loss of function, vWF does not bind well to platelets
vWD type 2N
vWF cannot bind to factor VIII
vWD type 3
Only AR one! Complete quantitative defect
Factors high in newborns (most low)
vWF and F8
Factors normal in newborns (most low)
fibrinogen or factor 8 (sometimes)
Factor with longest t1/2
Factor XIII = 10 days
Molecular basis of hemophilia A - severe
intron 22 inversion
Molecular basis of hemophilia A - mild/mod
point mutations in the factor VIII coding sequence
Molecular basis of hemophilia B - severe
small/large deletions
Molecular basis of hemophilia B - mild/mod
missense mutations