Other Coagulation Disorders

Question 1

christmas factor

Answer 1

factor IX

Question 2

the production of this is impaired by warfarin therapy

Answer 2

factors with vitamin k dependent activity

Question 3

Hemophilia B

Answer 3

• Christmas disease
• X-linked recessive
• males usually affected; females are carriers
• anatomic, soft tissue bleeding
• mild to severe depending on sevrity of deficiency

Question 4

treatment for hemophilia B

Answer 4

• factor IX concentrates
  > recombinant factor IX
  > prothrombin complex concentrates = vit K dependent coag factors
• small percentage = develop an inhibitor/antibody

Question 5

factor XI

Answer 5

• produced in liver
• circulates plasma complexed with HMWK
• contact factor in intrinsic pathway
  > activated by XIIa and HMWK
• only contact factor associate with bleeding problems

Question 6

Hemophilia C

Answer 6

• AKA Rosenthal syndrome
• autosomal inheritance; can be dom or rec depending on gene mutation
• more common in Ashkenazi Jewish population
• symptoms do not correlate with FXI deficiency (not linear)
  > usually mild bleeding
  > lab monitoring not useful
• treatment = plasma transfusions or FXI concentrates

Question 7

T or F. Acquired coagulation disorders are more common than inherited disorders

Answer 7

T!

usually involve multiple coagulation factor deficiencies

Question 8

Fibrinogen disorders

Answer 8

• Afibrinogenemia
• Hypofribrinogenemia
• Dysfibrinogenemia

Question 9

Afibrinogenemia

Answer 9

• rare; severe fibrinogen def or absence of fibrinogen

- severe bleeding after slight trauma/poor wound healing, hemarthroses (bleeding into joints)

Question 10

hypofibrinogenemia

Answer 10

• fibrinogenbelow ref range (<1.0g/L)

- bleeding mild to moderate

Question 11

dysfibrinogenemia

Answer 11

• alteration in fibrinogen structure leading to nonfunctional molecule
• variable bleeding
• variable coag results

Question 12

treatment for fibrinogen disorders

Answer 12

fibrinogen concentrate = prophylaxis, prior to surgical procedures, after trauma

blood products: plasma or cryoprecipitate; for active bleeds

Question 13

factor XIII deficiency

Answer 13

• AKA fibrin stabilizing factor
• poor wound healing (initial clot formed but starts bleeding again)
• bleeding from umbilical cord stump
• bleeding into soft tissues
• bruising
• CNS bleeding
• recurrent spontaneous abortion

Question 14

FXIII deficiency treatment

Answer 14

FXIII concentrate

Question 15

contact factors deficiencies

Answer 15

• no bleeding, but thrombosis is possible with FXII deficiency
  > role in activation of fibrinolysis
• aPTT prolonged
• PT normal
• not required for in vivo coagulation (XII, PK, HMWK)

Question 16

causes of acquired coag disorders

Answer 16

• abnormal or inadequate production (vit K deficiency, liver disease)
• increased use and or destruction (DIC, fibrinolysis)
• pathological inhibitors
• others = renal failure, acute trauma

Question 17

sources of vitamin K

Answer 17

• exogenous = diet (leafy greens)

- endogenous = synthesis by gut flora

Question 18

causes of factor deficiencies (vit K def)

Answer 18

• premature infant
• hospitalization and parenteral therapy
• malabsorption
• drugs: antibiotics, warfarin
• congenital vitamin K deficiency

Question 19

what is vitamin K’s role in coagulation?

Answer 19

gamma-carboxylation of II, VII, IX, X (not all serine proteases)

Question 20

diagnosis for vit K deficiency and treatment

Answer 20

aPTT and PT prolonged; supplements (oral or IV)

Question 21

thrombopoietin

Answer 21

Thrombopoietin is a glycoprotein hormone produced by the liver and kidney which regulates the production of platelets. It stimulates the production and differentiation of megakaryocytes, the bone marrow cells that bud off large numbers of platelets

Question 22

liver disease results in multiple hemostatic abnormalities

Answer 22

• decreased platelets: decreased thrombopoietin; splenic sequestration
• inadequate production of several coag factors
• inadequate production of regulatory proteins = antiplasmins, antithrombin, plasminogen, protein C and S
• abnormal factors (dysfibrinogenemia)
• defective clearance of hemostatic debris
• may result in DIC