Bleeding Disorders

Question 1

inherited deficiency of the (1) receptor which normally binds (2) allowing platelet adhesion to the sub-endothelial matrix

Answer 1

1. platelet GpIb 2. vWf refers to Bernard‐Soulier syndrome

Question 2

Qualitative defects in vWF are measured by?

Answer 2

electrophoresis only

Question 3

Describe type II von Willebrand disease

Answer 3

Qualitative defect due to defective assembly in vWF, resulting in loss of the most active form

Question 4

Infections‐mechanisms include damage to the vessel integrity by (1)

Answer 4

1. bacteria

refers to causes of petechiae or purpura

Question 5

Where is factor VIII made?

Answer 5

liver

Question 6

Syndromes which cause collagen defects of the vessel wall

Answer 6

“Scurvy Ehlers-Danlos Cushing’s syndrome”

Question 7

What is hemophilia B?

Answer 7

X linked recessive disorder of factor IX deficiency

Question 8

Prothrombin time measures effectiveness of?

Answer 8

extrinsic and common pathways

Question 9

platelet count, PT, and PTT in hemophilias

Answer 9

platelet count and PT are normal PTT prolonged

Question 10

What is hemophilia A?

Answer 10

X linked recessive disorder in factor VIII

Question 11

BINDS PLATELETS AND PROMOTES INTERACTION of vWF AND GLYCOPROTEIN Ib ON PLATELET MEMBRANE; it is the basis for the assay of vWF

Answer 11

RISTOCETIN (antibiotic)

Question 12

hereditary condition with tortuous dilated blood vessels that easily bleed

Answer 12

hemorrhagic telangiectasia; Weber‐Osler‐Rendu syndrome

Question 13

Add kaolin and cephalin to plasma and determine clotting time

Answer 13

partial thromboplastin time

Question 14

PT, PTT, and bleeding time for platelet dysfunction

Answer 14

PT and PTT normal bleeding time prolonged

Question 15

Treatment of hemophilia A

Answer 15

infusions of recombinant factor VIII

Question 16

How can bleeding in von Willebrand disease patients be avoided during procedures?

Answer 16

Prophylactic infusions of plasma concentrates containing factor VIII von Willebrand factor

Question 17

ACTIVATES FACTOR X IN THE INTRINSIC SYSTEM

Answer 17

Factor VIII

Question 18

Compare and contrast type I and type III von Willebrand disease

Answer 18

both are quantitative defects in amount of vWF type I - Autosomal Dominant; mild to moderate bleeding type III - autosomal recessive; severe bleeding, hemarthrosis (hemophilia like syndrome), very low levels of vWF

Question 19

DIC is frequently seen in what infections?

Answer 19

sepsis Rocky Mountain Spotted Fever Aspergilosis Malaria Histoplasmosis

Question 20

Drug induced petechiae or purpura involving skin and mucous membranes pathophysiology

Answer 20

“mechanism usually is immune complex deposition in capillaries and vascular damage”

Question 21

Causes of bleeding from thrombocytopenia

Answer 21

caused by decreased platelet production, decreased platelet survival (often on an immune basis) or via platelet consumption as in DIC splenomegaly dilution thrombocytopenia

Question 22

s/s of von Willebrand disease

Answer 22

mild bleeding post-procedure menorrhagia

Question 23

What organs are typically affected by DIC?

Answer 23

capillaries of brain, adrenal spleen, lungs, liver

Question 24

ristocetin cofactor activity in von Willebrand disease

Answer 24

decreased

Question 25

Manifestations of Henoch-Schonlein purpura

Answer 25

"purpuric skin rash, abdominal pain, intestinal bleeding and renal dysfunction"

Question 26

What is dilution thrombocytopenia?

Answer 26

massive transfusions of blood and blood products (trauma, liver transplant or cardiac surgery) cause a dilution thrombocytopenia which will require platelet transfusion to correct

Question 27

Add tissue thromboplastin in the presence of calcium ions to plasma and determine clotting time

Answer 27

prothrombin time

Question 28

The von Willebrand factor binds to (1) in the circulation and allows for increased half‐life of (1). This is essential as unbound (1) has a half‐life of \<3 hrs. It also is essential for platelet adhesion to sub endothelial (2) via platelet receptor (3)

Answer 28

1. factor VIII 2. collagen 3. GpIb.

Question 29

DIC is associated with many conditions including?

Answer 29

adenocarcinomas of pancreas, lung, stomach acute promyelocytic leukemia Infections: Sepsis Rocky Mountain Spotted Fever Aspergilosis Malaria Histoplasmosis OB complications trauma burns severe tissue hypoxia acidosis shock snake bite Abdominal aortic aneurysm rupture Heat stroke Acute hemolysis

Question 30

s/s of hemophilias

Answer 30

bruise easily; major bleeding from trauma or surgery; hemarthrosis leading to fibrotic and deformed joints; petechiae are ABSENT

Question 31

CAUSES PLATELET ADHESION TO SUBENDOTHELIAL COLLAGEN

Answer 31

vWF

Question 32

defects in release of platelet (1) which are required for normal platelet function

Answer 32

1. ADP and thromboxane refers to storage pool disease

Question 33

What is the inciting event of DIC?

Answer 33

due to abnormal activation of the coagulation system caused by release of tissue thromboplastin or endothelial damage

Question 34

DIC is characterized by?

Answer 34

widespread thrombosis leading to microangiopathic hemolytic anemia and organ dysfunction, followed by uncontrolled bleeding

Question 35

OB complications in which DIC is seen

Answer 35

abruption placentae septic abortion amniotic fluid emboli toxemia of pregnancy

Question 36

Thrombocytopenia may also be due to conditions causing (1) where there is sequestration of platelets in the enlarged organ

Answer 36

1. splenomegaly (cirrhosis e.g.)

Question 37

Bleeding from conditions that alter blood vessel wall; normal labs: Causes of petechiae or purpura involving skin and mucous membranes

Answer 37

Amyloidosis Vasculitis Vitamin C deficiency Infections Drug induced (Steroids) Collagen defects Henoch-Schonlein purpura Weber-Osler-Rendu syndrome

Question 38

Bleeding from conditions that alter the blood vessel walls results in?

Answer 38

petechiae or purpura involving skin and mucous membranes

Question 39

What are the manifestations of coagulation factor deficiencies?

Answer 39

"bleeding in GI and GU tracts hemarthrosis (bleeding into large joints) prolonged bleeding after procedures"

Question 40

Partial thromboplastin time measures effectiveness of?

Answer 40

intrinsic and common pathways

Question 41

What are the complications of DIC?

Answer 41

pulmonary, renal, circulatory failure and severe shock

Question 42

The effect of aspirin on (1) is irreversible and lasts up to (2) after discontinuing aspirin

Answer 42

1. cyclooxygenase 2. one week

Question 43

inherited deficiency of (1) required to form bridges between platelets and (2) (platelet aggregation).

Answer 43

1. Gp IIb‐IIIa 2. fibrinogen refers to Glanzman’s thrombasthenia

Question 44

Causes of acquired platelet defects

Answer 44

platelet dysfunction from use of plavix or aspirin and other non‐steroidal anti‐inflammatory drugs uremia

Question 45

Bleeding from conditions that alter blood vessel wall; normal labs: Lab findings in petechiae or purpura involving skin and mucous membranes

Answer 45

normal platelet count, PT and PTT and bleeding time

Question 46

Treatment of hemophilia B

Answer 46

Recombinant factor IX concentrates

Question 47

How do factor VIII levels predict severity of bleeding in hemophilia A? What are the cutoffs?

Answer 47

Factor VIII levels 1% of normal --\> severe bleeding Factor VIII levels 2-5% of normal —\> mild bleeding

Question 48

septicemia secondary to meningococcal or rickettsia infection

Answer 48

infectious cause of petechiae or purpura involving skin and mucous membranes

Question 49

What is the purpose of vWf binding to factor VIII?

Answer 49

increases half-life essential for platelet adhesion

Question 50

Heterozygote females can also rarely acquire the disorder from inactivation of the remaining normal Xchromosome

Answer 50

Hemophilia A

Question 51

What are the coagulation factor deficiencies? Which are inherited and which are acquired?

Answer 51

Inherited: Factor VIII Factor IX von Willebrand disease Acquired: DIC

Question 52

Where is vWF made?

Answer 52

endothelial cells

Question 53

What are the s/s of platelet dysfunction?

Answer 53

"Petechiae Easy bruising Nosebleeds Menorrhagia"

Question 54

What are some of the acquired coagulation disorders?

Answer 54

vitamin K deficiency parenchymal liver disease (cirrhosis)

Question 55

Platelets, factor VIII, PTT in von Willebrand disease

Answer 55

platelet counts normal factor VIII decreased PTT prolonged in types I and III