L9: Bleeding and coagulation disorders

Question 1

primary phase of hemostasis :

Answer 1

vasoconstriction
-platelet plug formation

Question 2

secondary phase of hemostasis :

Answer 2

deposition of fibrin mesh

Question 3

characteristics of vascular/ platelet bleeding :

Answer 3

-easy bruising / spontaneous bleeding from small vessels

-bleeding into skin and mucous membrane especially in mouth and nose

Question 4

characteristics of coagulation disorders :

Answer 4

-typically associated with hemarthroses , muscle hematomas

-bleeding after injury or surgery following a short delay

Question 5

normal platelet count :

Answer 5

150,000-450,000
(150-450x10^9/l)

Question 6

normal bleeding time :

Answer 6

3-10 minutes
-prolonged in thrombocytopenia , platelet functional disorders , von will brands disease

Question 7

bleeding time is prolonged in the following conditions :

Answer 7

-thrombocytopenia
-platelet functional disorders
-von will brands disease

Question 8

clotting time in all coagulation disorders is prolonged

Question 9

normal prothrombin time :

Answer 9

12-15 seconds

Question 10

prothrombin time is prolonged in :

Answer 10

abnormalities of extrinsic system :
- factors I,II,V,VII,X
-liver disease
-patient taking warfarin

Question 11

which test assesses the function of intrinsic system?

Answer 11

activated partial thromboplastin:
Factors I,II,V,VIII,IX,X,XI,XII

-It is prolonged if any of those factors are deficient (heparin therapy)

Question 12

normal thrombin time and when is it prolonged:

Answer 12

12 seconds
-prolonged in fibrinogen deficiency , dysfibrinogenemia , and heparin therapy

Question 13

correction tests are used for:

Answer 13

differentiating between deficiency of clotting factors and inhibitors of coagulation

Question 14

factor assays are used to:

Answer 14

confirm coagulation defects caused by inherited deficiency of single coagulation factor

Question 15

congenital vessel wall abnormalities :

Answer 15

-osler-weber-rendu syndrome (hereditary hemorrhagic telangiectasia

-Ehlers-danlos syndrome (connective tissue disorder

Question 16

acquired vessel wall abnormalities :

Answer 16

septicemia(meningococcal infection)
-vasculitis ( henoch-schonlein purpura , senile purpura)

-scurvy

-drug use (steroids)

Question 17

platelet count at
50-100:
20-50:
<20:

Answer 17

-moderate bleeding after injury

-purpura may occur+ hemorrhage after injury

-purpura is common+ spontaneous hemorrhage from mucous membranes + risk of intra-cranial hemorrhage

Question 18

impaired production of platelets occurs due to:

Answer 18

-bone marrow failure
-infiltration (leukemias , myelofibrosis , carcinoma )
-megaloblastic anemia

Question 19

excessive destruction of platelets is due to :

Answer 19

-idiopathic thrombocytopenic purpura

-connective tissue disease(SLE)

-drugs like heparin

excessive consumption (DIC)

Question 20

idiopathic thrombocytopenic purpura :

Answer 20

immune destruction of platelets–

autoantibodies directed against GP IIb and IIIa

premature removal of platelets by monocytes

-

Question 21

difference between idiopathic purpura in children and in adults
:

Answer 21

children :
-acute
-self limiting
-following viral infection
-immunization

adults:
-insidious onset
-chronic course with remissions and relapse
-associated with auto-immune disorders.

Question 22

idiopathic purpura treatment :

Answer 22

-prednisolone
-platelet transfusion
-intravenous immunoglobulin

second line:
-increased dose of steroids
-spleenectomy

Question 23

platelet function disorders :(deficiency in what ?)
-glanzmann’s thromboasthenis :
-berrard-soulier syndrome
-storage pool disease :

Answer 23

-G: IIb , IIIa ( same GP AFFECTED IN idiopathic purpura)
-B: IIb
-Storage: lack of dense bodies

Question 24

examples of acquired platelet function disorders

Answer 24

-myeloproliferative disorders
-renal failure
-chronic liver disease
-paraproteinemias
-drug induces: asprin and NSAIDs

Question 25

which drugs can cause acquired platelet function disorders ?

Answer 25

NSAIDs , aspirn

Question 26

inherited and acquired coagulation disorders of secondary haemostasis :

Answer 26

-involvw deficiency of a single factor : -Hemophilia A,B -von Willebrand's disease acquired: -more frequent -deficiency of several factors ex: disseminated intravascular coagulation , liver disease, renal failure , vitamin K deficiency

Question 27

sequelae of hemophilia :

Answer 27

-chronic hemophilic arthropathy -fibrosis -muscle shortening -tendon nerve compression by hematoma

Question 28

hemophillia diagnosis BT: CT: PT: APTT:

Answer 28

Bleeding time is normal clotting time is prolonged prothrombin time is normal Activated partial TT is prolonged

Question 29

hemophilia B is caused by deficiency of :

Answer 29

factor IX -CHRISTMAS DISEASE

Question 30

function of vW factor :

Answer 30

-acts as a carrier protein for factor VIII - helps platelets adhere to sub-endothelial structures gene for it is located on chromosome 12

Question 31

lab diagnosis for von willibrands disease : BT: PT: APTT:

Answer 31

bleeding time is prolonged prothrombin time is normal APPTT: prolonged

Question 32

which clotting factor is reduced in patients suffering from vW syndrome ?

Answer 32

factor VIII

Question 33

Causes of disseminated intra vascular coagulation :

Answer 33

-septicemia , meningococcal infection , falciparum malaria -malignancies -obstetric causes -snake bite =varies from bleeding to profound hemostatic failure with wide spread hemorrhages (PT , APTT,TT prolonged)

Question 34

how can liver disease affect platelet count?

Answer 34

-thrombocytopenia from hypersplenism -can also affect functionality of platelets

Question 35

bleeding manifestations of renal failure are of ____ type

Answer 35

platelet

Question 36

what are the vitamin K dependant factors ?

Answer 36

II , V , XII, IX,X protein C and S

Question 37

Causes of vitamin K deficiency

Answer 37

-Inadequate stores as in the new born Hemorrhagic disease of the new born 2. Severe malnutrition 3. Malabsorption of Vit K as in cholestatic Jaundice 4. Oral anticoagulants