Week 10 Intro to haematology

Question 1

Define haematology?

Answer 1

Biology and pathology of the cells that normally circulate in the blood

Question 2

What is Haemopoiesis?

Answer 2

The physiological developmental process that gives rise to the cellular components of blood

Question 3

What can single multipotent haemopoietic stem cell differentiate into?

Answer 3

They can divide and differentiate to form different cell lineages that will populate the blood

Question 4

What is the characteristic of haemopoietic Stem Cell?

Answer 4

Differentiation potential for all lineages
High proliferative potential
Long term activity throughout the lifespan of the individual
Self renewal

Question 5

What is Symmetric

self-renewal?

Answer 5

Increase stem cell pool – NO generation of differentiated progeny

Question 6

What is asymmetric self renewal?

Answer 6

Maintain stem cell
pool – generation
of differentiated
progeny

Question 7

What is Lack of

self-renewal?

Answer 7

Deplete stem cell pool – generation of ONLY differentiated progeny

Question 8

What is lack of sell renewal?

Answer 8

Maintain stem cell pool – NO differentiated progeny

Question 9

What is the life span of RBC?

Answer 9

120 days

Question 10

Give example of myeloids?

Answer 10

Granulocytes (White blood cells)
Erythrocytes (Red blood cells)
Platelets

Question 11

Give examples of lymphoids?

Answer 11

B-Lymphocytes (White blood cells)

T-lymphocytes (White blood cells)

Question 12

What stage does haemopoiesis start?

Answer 12

Haemopoiesis starts at day 27 in the aorta gonad mesonephros region,
expands rapidly at day 35, then disappear at day 40

Question 13

What does the disappearance at day 40 of haemopoiesis correlate with?

Answer 13

This “disappearance” correlates with the migration of these hematopoietic stem cells to the foetal liver, which becomes the subsequent site of haemopoiesis.

Question 14

What is the function of blood cell?

Answer 14

Oxygen transport
Coagulation
Immune response to infection
Immune response to abnormal cells (senescent, malignant etc)

Question 15

What is polycythaemia, anaemia and Relative polycythaemia

Answer 15

Reduced red cells = anaemia
Raised red cells = polycythaemia

Relative polycythaemia, when plasma volume is reduced > dehydrated

Question 16

What is the structure of RBC?

Answer 16

bi- concave discs

Question 17

Give 3 examples of granulocytes?

Answer 17

Have cytoplasmic granules
Neutrophils
Eosinophils
Basophils

Question 18

What is the most common white cell in adult blood?

Answer 18

Neutrophils

Question 19

When do you see increased number of neutrophils?

Answer 19

Increased numbers in presence of infection - neutrophilia

e. g. bacterial infection
e. g. inflammation

Question 20

When do you see decreased numbers of neutrophils (neutropenia)?

Answer 20

e.g. side effect of a drug
Chemotherapy or a variety of drugs as a side effect
Also SLE autoimmune disease that causes neutropenia

Question 21

How long do neutrophils live for?

Answer 21

Only for a few hours 6-8

Question 22

When do you see increased number of eosinophilias?

Answer 22

e. g Parasitic infection

e. g. Allergies

Question 23

What condition do you see increased number of basophils?

Answer 23

Rare

Chronic Myeloid Leukaemia

Question 24

What are monocytes?

Answer 24

Phagocytic & antigen-presenting cells

Question 25

When do you see increase number of monocytes?

Answer 25

TB

Question 26

What are Natural killer cells?

Answer 26

large granular lymphocytes Recognise “non-self” Cells, viruses

Question 27

What is the action of B lymphocytes?

Answer 27

Adaptive immune system Rearrange the immunoglobulin genes to enable antigen specific antibody production Provide specific immunoglobins when under a threat Formed because the specific immunoglobin gene is re ordered so they can be produced by plasma cells

Question 28

What is the action of T cells?

Answer 28

``` rearrange the T-cell antigen receptor cell-mediated immunity target specific cytotoxicity Interact with B cells, macrophages Regulate immune responses ```

Question 29

What is lymphocytosis?

Answer 29

Increase number of lymphocytes

Question 30

What can cause lymhocytosis?

Answer 30

Atypical lymphocytes of glandular fever (infectious mononucleosis) Chronic lymphocytic leukaemia

Question 31

What is a cause of lymphopenia (reduce numbers)?

Answer 31

Post bone marrow transplant

Question 32

What can cause plasmacytosis?

Answer 32

Infection | Myeloma

Question 33

What are plateleets dervived from?

Answer 33

Platelets are derived from bone marrow megakaryocytes | Megakaryocytes fragment to form the platelets

Question 34

What is the action of platelets?

Answer 34

Together with soluble plasma clotting factors and endothelial cells form part of the blood clotting system Aggregate to plug holes in damaged blood vessels

Question 35

What are diagnostic tests for haemotology?

Answer 35

Full Blood Count Blood Film (or “smear”) Coagulation Screen

Question 36

What is tested in full blood count?

Answer 36

Haemoglobin concentration Red cell parameters MCV (mean cell volume) MCH (mean cell Hb) White Cell Count (WCC) Platelet Count

Question 37

What is Coagulation Screen?

Answer 37

Tests measure the time taken for a clot to form when plasma is mixed with specified reagents

Question 38

What parts of the coagulation cascaed can be assayed in coagulation screen?

Answer 38

Prothrombin Time Activated Partial Thromboplastin Time Thrombin Time

Question 39

From where is bone marrow taken from?

Answer 39

Under local anaesthetic, liquid marrow is aspirated from the posterior iliac crest of the pelvis

Question 40

What are the 3 key factors to collecting a blood specimen?

Answer 40

appropriate sample from the patient collected into EDTA anticoagulated blood Samples should get to the lab promptly since EDTA artefact can affect the results.

Question 41

What is the reference range used when doing tests?

Answer 41

the set of values for a given test that incorporates 95% of the normal population

Question 42

What is sensitivity?

Answer 42

defined as the proportion of abnormal results correctly classified by the test expresses the ability to detect a true abnormality

Question 43

What is the formula of sensitivity?

Answer 43

TP / ( TP+FN  )

Question 44

What is specificity?

Answer 44

Defined as the proportion of normal results correctly classified by the test Expresses the ability to exclude an abnormal result in a healthy person

Question 45

What is the formula of specificity?

Answer 45

TN / (TN+FP)     

Question 46

When would it be normal to have a abnormal lymphocyte count?

Answer 46

post-splenectomy mild lymphocytosis | 3 months post-bone marrow transplant lymphopenia

Question 47

Give 5 examples of microcytic hypochromic?

Answer 47

``` Iron deficiency Thalassaemia Anaemia of chronic disease Lead poisonng Sideroblastic anaemia ```

Question 48

What is the mean cell volume and mean cell HB of microcytic hypochromic?

Answer 48

MCV

Question 49

What is the classification of normocytic normochromic?

Answer 49

MCV 80-95 fl & MCH ≥ 27 pg

Question 50

GIve example of normocytic normochromic?

Answer 50

``` Many haemolytic anaemias Anaemia of chronic disease (some cases) After acute blood loss Renal disease Mixed deficiencies Bone marrow failure ```

Question 51

What is the calssifciation of macrocytic?

Answer 51

MCV >95 fl

Question 52

Give example of Macrocytic?

Answer 52

Megaloblastic: Vitamin B12 or folate deficiency Non-megaloblastic: alcohol, liver disease, myelodysplasia, aplastic anaemia etc

Question 53

What is megloblastic anemia?

Answer 53

Megaloblastic anemia is the results from inhibition of DNA synthesis during red blood cell production