Intro to Haem

Question 1

Haematopoiesis (from bone marrow to circulation) outline the process then the products…

Answer 1

uncommited stem cell > committed stem cell > following below: erythroblast –> erythrocyte, megakaryocyte –> platelets, other cells formed: neutrophils, monocytes, basophils, eosinophils, lymphocytes

Question 2

name the myeloid cells

Answer 2

erythrocytes, mast cells, platelets, neutrophils, monocytes, basophils, eosinophils,

Question 3

name the lymphoid cells

Answer 3

NK CELLS, T cells AND B cells

Question 4

stem cells are…

Answer 4

totipotent and can self renew

Question 5

outline the process of erythroid differentiation

Answer 5

eryhtroblast –> reticulocyte –> erythrocyte

Question 6

where is epo (erythropoietin) made?

Answer 6

in the kidneys in response to hypoxia

Question 7

what is reticulocyte count?

Answer 7

a measure of rbc production

Question 8

whata er the ocnsequences of anaemia?

Answer 8

poor gas transfer, dyspnoea, fatigue. (may be casued by increased loss - bleeding, haemolysis) (may also be caused by decreased rpoduction - haemantics deficiency e.g. iron, folate, vitB12 or congenitally - thalassaemias)

Question 9

what is the function of platelets

Answer 9

haemostasis (clotting)

Question 10

what regulates platelet production?

Answer 10

thrombopoietin (produced in the liver, Regulation by platelet mass feedback Agonists (romiplostim, eltrombopag) used therapeutically, Lifespan =7 days)

Question 11

funciton of neutrophils

Answer 11

Function: to ingest and destroy pathogens, especially bacteria and fungi, Interleukins (‘between white cells’) and CSFs (colony stimulating factors) granulocyte colony stimulating factor (G-CSF), regulation by immune responses , Macrophages, IL-17, Lifespan =1-2 days, Speed of response=few hours

Question 12

neutrophlia…

Answer 12

Production regulated by granulocyte-colony stimulating factor (G-CSF) - Infection, Left shift, toxic granulation, Inflammation eg MI, postoperative, rheumatoid arthritis. G-CSF used therapeutically. Neutropenia, Mobilisation of stem cells.

Question 13

neutropenia…

Answer 13

Decreased production - Drugs, Marrow failure
Increased consumption - Sepsis, Autoimmune
Altered function - eg chronic granulomatous disease

Question 14

what are monocytes?

Answer 14

Function: to ingest and destroy pathogens, especially bacteria and fungi, Subset of monocytes migrate into tissues and become macrophages or dendritic cells, Some populations of macrophages self-maintaining.

Question 15

what do eosinophils do?

Answer 15

fight parasites and become active in allergies

Question 16

what are Lymphocytes?

Answer 16

Adaptive, versus innate, immune system, Immunological memory, Surface antigens: CD markers. Lymphocytosis - Infectious mononucleosis, Pertussis. Lymphopenia - Usually post-viral, lymphoma
Produced in bone marrow
B cells mature in bone marrow, T cells in thymus
Circulate in blood, lymph and lymph nodes
Differentiate into effector cells in secondary lymphoid organs (lymph nodes or mucosal associated lymphoid tissue)

Question 17

list the subtyoes of lmyphocytes and their functions

Answer 17

B cells – make antibodies
T cells – Helper, cytotoxic, regulatory
NK cells

Question 18

what is positive selction?

Answer 18

if gene rearrangement results in a functional receptor the cell is selected to survive – positive selection

Question 19

what is negative selection?

Answer 19

If the receptor recognises ‘self’ antigens - the cell is triggered to die – negative selection: tolerance

Question 20

HLA TYPE 1 AND 2

Answer 20

Human Leukocyte antigen - immune cells read HLA-barcode on cells to help identify self vs non-self cells or infected vs noninfected cells (an immune response is triggered if a infected cell is identified).
Class I: displays internal antigens on all nucleated cells
Class II: displays antigens eaten by professional antigen presenting cells

Question 21

what systemic dieseases effect the blood?

Answer 21

rheumatoid arthritis, Anaemia of chronic disease, Iron deficiency, Folate deficiency, Immune haemolysis, Neutrophilia, Immune thrombocytopenia, Cytopenias, secondary to medication, Felty syndrome (triad of RA, splenomegaly and neutropenia, resulting in susceptibility to bacterial infections)

Question 22

what are formed if there is too much plasma?

Answer 22

Paraproteins

Question 23

name some disgnostic tools

Answer 23

FBC, clotting times, INR, chemical assays (Fe (ferritin), B12, Folate), marrow aspirate and trephine biopsy, lymph node biopsy, imaging (plain film, CT),

Question 24

Haematology Tx

Answer 24

Replacement, Blood, Haematinics, Coagulation factors, Plasma exchange, Transplantation, Drugs: Cytotoxics, Monoclonal antibodies, inhibitors of cellular proliferation, Immunosuppressants, Inhibitors of coagulation, Inhibitors of fibrinolysis