thrombophilia

Question 1

what are the two types of thrombophilia ?

Answer 1

inherited and acquired

Question 2

what are the different causes of inherited thrombophilia?

Answer 2

1- deficiency of natural anticoagulants
2- prothrombin mutation
3- defect in fibrinolytic system
4- hyper-homocysteinemia

Question 3

what are the types of acquired thrombophilia ?

Answer 3

lupus anticoagulant
myeloproliferative disease : polycythemia
heparin induced thrombocytopenia and thrombosis

Question 4

what are the different deficiencies of natural coagulants ?

Answer 4

anti thrombin 3 deficiency
heparin cofactor 2 deficiency
protein C or S deficiency
factor V leiden

Question 5

what happens with factors V leiden ?

Answer 5

resistance to activated protein C

Question 6

when do we suspect anti-thrombin deficiency ?

Answer 6

1- in young patients
2- pregnancy related VT
3- therapeutic heparin in excess with no prolongation in PTT
suggestive of heparin resistance

Question 7

what are the acquired conditions associated with anti thrombin deficiency ?

Answer 7

nephrotic syndrome
DIC
severe liver disease

Question 8

what is the genetic inheritance associated with antithrombin deficiency ?

Answer 8

autosomal dominant

Question 9

what is the function of protein C ?

Answer 9

cleavage of factor 8 and factor 5

Question 10

what is the end result of protein C deficiency ?

Answer 10

associated with hypercoaguable state

Question 11

what are the vitamin K dependent factors ?

Answer 11

protein s
protein C
factor 2,7,9,10

Question 12

what testing is used for protein C ?

Answer 12

functional assay oor antigenic assay
ELISA
immunoelectrophoresis

Question 13

what is the most common inherited thrombophilia ?

Answer 13

factor V leiden
activated protein c resistance

Question 14

what is factor V deactivated by ?

Answer 14

protein C , if it cannot be cleaved it makes it more likely for the formation of VTE

Question 15

what happens in prothrombin mutations ?

Answer 15

increase in prothrombin levels , increases thrombotic risk

Question 16

what does a mutation in MTHFR cause ?

Answer 16

homocystenuria

Question 17

what is the diagnostic criteria for APL ?

Answer 17

lab criteria :
anticardiolipin
anti b2 Glycoprotein
lupus anticoagulant
all positive , on 2 separate occasions 12 weeks apart

clinical criteria :
vascular thrombosis
pregnancy complications

Question 18

what happens in heparin indued thrombocytopenia ?

Answer 18

before heparin therapy perform platelet count
if the platelete count decreases , this is HIT

Question 19

elevation of RBC and thrombophilia ?

Answer 19

polycythemia vera

Question 20

prolonged PTT not corrected by the addition of normal plasma ( mixing study) suggests ?

Answer 20

lupus anticoagulant or acquired inhibitors

Question 21

who should be tested for inherited thrombophilia ?

Answer 21

increased risk of recurrence in early ages
patients with a positive family history

Question 22

what are the tests for inherited thrombophilia ?

Answer 22

factor V leiden
Protein C and protein S deficiency
antithrombin 3 deficiency
prothrombin mutation
MTHFR mutation

Question 23

what is the best time for performing thrombophilia testing ?

Answer 23

1- usually best delayed until at least 1 month after completion of a course of anticoag therapy
2- should be avoided in pregnancy or if thee patient is on the pill

Question 24

what type of heparin is associated with HITT ?

Answer 24

unfractionated or heavy weight heparin

Question 25

what does persistant high level 1 month after stoppage of warfarin suggest ?

Answer 25

may predict recurrence

Question 26

what tests can be used to detect defective fibrinolytic system ?

Answer 26

plasminogen
PA
PAI

Question 27

what tests can be performed to detect increased platelet activity ?

Answer 27

increased PF4
PFA-100 decreased closure time

Question 28

what is the thrombophilia panel by PCR ?

Answer 28

Factor V G1691A (Leiden)
Factor II Prothrombin G20210A
MTHFR C677T/A1298C

Question 29

relationship between protein c and protein s?

Answer 29

PS increases the affinity off PC to bind to thee phospholipid on the surface of platelets

Question 30

what is the inactive form of protein S ?

Answer 30

C4b bound PS

Question 31

if everything is high except fibrinogen and platelets what is the most likely diagnosis ?

Answer 31

DIC