Bleeding Disorders

Question 1

What factor is deficient in Hemophilia A?

Answer 1

factor VIII

Question 2

What factor is deficient in Hemophilia B?

Answer 2

factor IX

Question 3

What type of inheritance pattern is exhibited by Hemophilia A and B?

Answer 3

X-linked

Question 4

Factor activity for severe hemophiliacs and complications

Answer 4

<1%
spontaneous bleeds into joints and deep tissue
require factor replacement on ongoing basis

Question 5

Factor activity and complications in moderate hemophiliacs.

Answer 5

1-5%

similar bleeds, but more often precipitated by minor trauma

Question 6

factor activity and complications in mild hemophiliacs.

Answer 6

> 5%

may be asymptomatic until challenged by significant trauma or injury

Question 7

Describe factor XI deficiency.

Answer 7

somewhat variable, mild bleeding tendency

relatively present in Ashkenazi Jew population

Question 8

Describe factor XIII deficiency.

Answer 8

rare condition
classically presents with umbilical stump bleeding in the neonate
associated with defective wound healing and spontaneous abortion

Question 9

two types of deficiencies in von Willebrand Disease

Answer 9

quantitative or qualitative

Question 10

What factor is associated with vWF?

Answer 10

factor VIII

Question 11

what type of bleeding is common in von Willebrand Disease?

Answer 11

mucocutaneous bleeding
(bleeding is usually mild to moderate)
soft tissue/joint bleeding in more severe cases

Question 12

Inheritance pattern of most common type of von Willebrand disease.

Answer 12

autosomal dominant

characterized by a quantitative decrease in vWF

Question 13

which type of vWD is characterized by quantitative reduction?

Answer 13

type I vWD

treated with desmopressin which stimulates release of vWF from endothelial cells

Question 14

which type of vWD is characterized by qualitative, abnormal vWF protein?

Answer 14

type II vWD

treated with replacement therapy

Question 15

What receptor is affected by Glanzmann’s Thrombasthenia?

Answer 15

Gp IIb/IIIa

Question 16

what is main problem in Glanzmann’s Thrombasthenia?

Answer 16

defective platelet aggregation

Question 17

What receptor is affected by Bernard-Soulier syndrome?

Answer 17

Gp Ib V-IX

Question 18

what is main problem in Bernard-Soulier syndrome?

Answer 18

defective vWF-dependent adhesion by platelets

Question 19

What is the most common cause of isolated thrombocytopenia in otherwise healthy individuals?

Answer 19

Idiopathic (autoimmune) thrombocytopenic purpura (ITP)

Question 20

What characterizes idiopathic (autoimmune) thrombocytopenic purpura (ITP)?

Answer 20

anti-platelet antibodies, often directed against GP IIb/IIIa complexes, that result in antibody and Fc dependent platelet destruction (primarily in spleen)

Question 21

What type of autoantibody can cross the placenta?

Answer 21

IgG

Question 22

What types of drugs most commonly can cause drug-induced immune thrombocytopenia?

Answer 22

antibiotics (penicillin or sulfonamide-related), quinine compounds

Question 23

What should be stopped in the evaluation of thrombocytopenia?

Answer 23

all non-essential drugs

Question 24

What defines microangiopathic hemolytic anemia (MAHA)?

Answer 24

presence of RBC fragmentation (schistocytes) on the blood smear, varying degrees of anemia, elevated LDH, usually an elevated retic count

Question 25

When coagulopathy is present along with MAHA, what condition does it suggest?

Answer 25

disseminated intravascular coagulation (DIC)

Question 26

What protein becomes severely deficient in thrombotic thrombocytopenic purpura (TTP)?

Answer 26

ADAMTS13

Question 27

What is the function of ADAMTS13?

Answer 27

it is a vWF cleaving protease that prevents formation of large vWF multimers that partially unfold and bind to platelets

Question 28

What characterizes TTP?

Answer 28

MAHA, thrombocytopenia, fever, dysfunction of various organs (particularly brain (change in mental status) and kidneys)

Question 29

Is coagulopathy affected in TTP?

Answer 29

No, there is no consumption of clotting factors

Question 30

Treatments for TTP?

Answer 30

plasma exchange or infusion | steroids

Question 31

What organ is mostly involved in hemolytic-uremic syndrome (HUS)?

Answer 31

kidneys

Question 32

Classic symptom in hemolytic-uremic syndrome (HUS)

Answer 32

bloody diarrhea

Question 33

What type of infection is commonly found in hemolytic uremic syndrome (HUS)?

Answer 33

enterohemorrhagic bacteria expressing Shiga-like toxin (E. coli) triggers endothelial injury

Question 34

Can idiopathic forms of HUS occur?

Answer 34

yes

Question 35

What enzyme synthesis is blocked by aspirin and NSAIDs?

Answer 35

Thromboxane

Question 36

What pathway does aspirin and NASAID block?

Answer 36

Cox-1

Question 37

describe effect of clopidogrel on platelet activation.

Answer 37

clopidorgrel inhibits ADP-mediated platelet activation

Question 38

4 causes of thrombocytosis

Answer 38

reactive myeloproliferative disorders post-splenectomy or asplenia iron-deficiency

Question 39

What is the effect of Vitamin K deficiency on both PT and aPTT?

Answer 39

both are prolonged

Question 40

describe Hemorrhagic disease of the newborn (HDN)

Answer 40

newborn babies are vulnerable to bleeding due to vitamin K deficiency there is poor transport of Vitamin K across placenta

Question 41

What is done to reduce risk of Vitamin K in infants?

Answer 41

all receive prophylactic Vitamin K

Question 42

Why can liver disease cause coagulopathy?

Answer 42

many of the coagulation factors are made in the liver

Question 43

What occurs in disseminated intravascular coagulation (DIC)?

Answer 43

thrombin and plasmin are generated at a rate that exceeds the ability of their natural inhibitors (antithrombin and antiplasmin) to neutralize them

Question 44

What usually causes DIC?

Answer 44

exposure to excessive amounts of Tissue Factor

Question 45

What problems are caused by DIC?

Answer 45

consumption of platelets (thrombocytopenia), depletion of inhibitors, bleeding, deposition of fibrin in small vessels with resulting microangiopathy, varying degrees of organ dysfunction

Question 46

Common lab findings in DIC

Answer 46

thrombocytopenia Prolonged PT and aPTT elevated FDP (fibrin degradation product) and D-dimer decreased fibrinogen red cell fragmentation on the blood smear

Question 47

How can you bypass inhibitors to factor VIII in treatment?

Answer 47

give factor VIIa

Question 48

What plays an important role in causing DIC?

Answer 48

diffuse endothelial injury