Hema. Mod.A Lec4

Question 1

platelets disorders could be (2)

Answer 1

1-Low number

2-Abnormal Function

Question 2

bleeding grade 0:

Answer 2

no bleeding

Question 3

bleeding grade 1: (3)

Answer 3

petechiae

ecchymosis

occult blood loss detected by stool test

Question 4

bleeding grade 2: called gross bleeding (not requiring transfusion) (3)

Answer 4

epistaxis (nose bleeding)

hematuria (blood in urine)

hematemesis (vomiting of blood

Question 5

bleeding grade 3:

Answer 5

hemorrhage requiring transfusion

Question 6

bleeding grade 4:

Answer 6

hemorrhage with HEMODYNAMYIC compromise (ex: low blood pressure shock)

retinal hemorrhage with visual impairment

cns hemorrhage

fatal at any organ

Question 7

normal platelet count:

Answer 7

150k-400k

Question 8

if plat count is >500k what will happen ?

Answer 8

thrombosis or hemorrhage (defect in plat function)

Question 9

bone marrow examination is either (2)

Answer 9

aspiration

trephine biopsy

Question 10

point of bone marrow examination:

Answer 10

detect cause of plat defect

Question 11

function of spleen normally:

Answer 11

engulf 1/3 of platelets

Question 12

What is thrombocytopenia?

Answer 12

decrease in platelet count below normal range

Question 13

causes of thrombocytopenia?

Answer 13

defect in:

Bone Marrow (defect in production of megakaryocyte)

Peripheral blood

Question 14

defect in bone marrow in cases of thrombocytopenia: (9)

Answer 14

AFFECT MEGAKARYOCYTE PRODUCTION:

1-aplastic anemia: no blood cells are produced due to DEFECT IN STEM CELLS

2-leukemia: due to increase in BLAST CELLS which suppress the production of MEGAKARYOCYTE

3-myelodyplastic syndrome: defect in STEM cells

4-myelofibrosis: fibrosis of bone marrow

5-bone marrow infiltration with CARCINOMA or LYMPHOMA

6- multiple myeloma
7-megaloblastic anemia
8-HIV infection
9-cytoxic drugs

Question 15

defect in peripheral blood in cases of thrombocytopenia:

Answer 15

WHEN BONE MARROW EXAMINATION SHOW NO DEFECT

1-due to consumption or destruction of platelets:

A- immune causes:

• autoimmune idiopathic thrombocytopenic purpura ITP
• systemic lupus erythromatus
• lymphocytic leukemia (LYMPOHMA)
• infections: HIV or Helicobacter
• drug induced (ex: heparin)
• post transfusion purpura

B-non immune causes:

• DIC (disseminated intravascular coagulation)
• TTP (thrombotic thrombocytopenic purpura

2- due to abnormal distribution of platelets:

-due to splenomegaly (caused by increased in engulfment of platelets) ex liver disease (malaria, hepatitis)

-Dilutional loss = hemodilation
due to massive transfusion of stored blood to bleeding patients

Question 16

Types Of ITP

Answer 16

Chronic and Acute

Question 17

Why is it called IDIOPATHIC ?

Answer 17

due to Ab attacking self Ag with no known reason

Question 18

Chronic ITP (in whom it occurs, what it’s associated with)

Answer 18

occurs in females ONLY (15-50) and it increases with age

it is idiopathic or associated with:
1- SLE (autoimmune disease)
2-CLL
3-AIHA
4-HIV (not autoimmune disease)
5-HD (hodjkin disease)

most of the disease that cause ITP are autoimmune diseases.

Question 19

Mechanism of ITP

Answer 19

autoantibodies attack plat.ag.

then these platelets go to the spleen to be destructed.

Question 20

Clinical picture of ITP (3)

Answer 20

1- petechial hemorrhage, easy brusing, MENORRHAGIA

2-epistaxis,gum bleeding

3-tend to relapse, remit (تروح و تجي)

Question 21

How to diagnose ITP ? (3)

Answer 21

1-CBC, blood film: show decrease in platelets

2- BM aspiration: if megakaryocytes are normal then the defect is in peripheral blood, if megakarocytes are low then defect is in BM.

3- detection of autoantibodies (not an effective test)

Question 22

Treatment of chronic ITP

Answer 22

corticosteroids to increase platelets.

Question 23

Acute ITP (when it happens, in whom it occurs, treatment)

Answer 23

Last short time, occurs suddenly in children with cold virus.

appears as dots on skin.
occurs due to auto antibodies attacking ag causing destruction of platelets.

is treated rapidly by STEROIDS and IV IMMUNOGLOBULIN

Question 24

TTP: (normal function of VWF and how it relates to TTP)

Answer 24

usually VWF is synthesized in endothelial cells as MULTIMER and is converted to MONOMER by ADAMTS13 to circulate.

TTP occurs due to deficiency of ADAMTS13 which causes increased VWF MULTIMERS which increase platelet aggregation leading to THROMBOCYTOPENIA

Question 25

why is ADAMTS13 deficient in TTP ?(2)

Answer 25

1- due to autoantibodies attacking the enzyme 2- absence of enzyme

Question 26

clinical picture of TTP: (5)

Answer 26

PENTAD of: 1- Fever 2-Thrombocytopenia 3-Microangiopathic hemolytic anemia (destruction of RBCs due to formation of thrombus) 4-Neurological abnormalities 5- Renal Failure

Question 27

Diagnosis of TTP

Answer 27

1- high LDH due to hemolysis 2- normal PT and APTT 3- absence of ADAMTS13 or is severely reduced

Question 28

Disorders of platelets functions: are suspected in (3)

Answer 28

1- normal platelet count 2- patient has skin and mucosal hemorrhage 3- prolonged BLEEDING TIME

Question 29

Types of Hereditary disorders of platelet function (acquired is not with us): (2)

Answer 29

1- Glanzmann thrombasthenia 2- Bernard soulier syndrome

Question 30

Glanzmann thrombasthenia:

Answer 30

Defect in glycoprotein ( Gp2b/3a) which is a receptor for fibrinogen. when u add aggregating agent to platelets no response will occur, so defect is in function.

Question 31

Bernard soulier syndrome:

Answer 31

Defect or missing Gp1b receptor which is the receptor present in platelets. As a result VWF can't bind, no platelet adhesion.

Question 32

Both hereditary disorders of plat. function are diagnosed by:

Answer 32

aggregation test.

Question 33

Do all patients having purpuric eruption have platelet disorders ?

Answer 33

no, it can be due to vascular disorders which can be acquired or congenital

Question 34

congenital vascular disorders:

Answer 34

1- hereditary hemorrhagic telangiectasia 2- C.T disorders (Ehlers-Danlos syndrome) (rubber man in circus)

Question 35

acquired vascular disorders:

Answer 35

1- easy bruising syndrome: -in females, blueness in her body without any trauma 2- senile purpura: -during aging, due to atrophy of C.T that support blood vessels causing escape of blood 3-infection: can cause damage to C.T 4-steroid purpura: due to consumption of CORTICOSTEROID causing atrophy of C.T supporting blood vessels 5- Scurvy: due to decreased vit.c that has a role in blood vessel synthesis ``` 6- Henoch-Schonlein syndrome: common in children, occur after acute infection, can cause vasculitis due to IgA, purpuric rash. ```

Question 36

causes of thrombocytosis:

Answer 36

1- HEMORRHAGE OR TRAUMA: post operative, why? because they lead to bleeding so BM tries to compensate the loss of platelets. 2-chronic iron deficiency 3-malignancy (cancer) 4-chronic infection 5-post splenectomy (normally spleen engulfs 1/3 of platelets, so if there is no spleen, these platelets are going to the blood circulation and increase causing THROMBOCYTOSIS:

Question 37

if megakaryocyte is decreased in thrombocytopenia, what is the cause ?

Answer 37

Acute leukemia or any BM disease.

Question 38

if plat. count is 1 million, what can occur ?

Answer 38

thrombosis, hemorrhage, epistaxis

Question 39

if platelet is 190k, and the bleeding time is prolonged | also low Hb

Answer 39

anemia or PLATELET DYSFUNCTION.