Blood Cell Abnormalities

Question 1

What is anaemia?

Answer 1

A reduction in the amount of haemaglobin in a given volume of blood, below what would be expected in comparison with a healthy subject of the same age and gender

Question 2

What are the four mechanisms of anaemia?

Answer 2

Production - reduced production of RBC
Pooling - RBC may pool in the spleen
Loss - RBCs may be lost due to blood loss
Survival - reduced survival of RBCs

Question 3

What is meant by microcytic RBCs

Answer 3

Smaller than usual - normally hypochromic and can therefore be identified by their larger area of central pallor

Question 4

What causes microcytic anaemia?

Answer 4

Occurs either due to a loss of HAEM or GLOBIN
HAEM loss = due to iron deficiency
GLOBIN loss = thalassemia

Question 5

What causes an iron deficiency?

Answer 5

Heavy menstruation, diet, malabsorption,

Question 6

What is macrocytic anaemia?

Answer 6

When the red blood cells are larger than normal

Question 7

What causes megaloblastic anaemia?

Answer 7

Deficiency of folate or B12 - cells are continuing to divide by cannot synthesize the DNA therefore just keep growing

Question 8

What causes macrocytosis?

Answer 8

Abnormal haematopoiesis - red cell precursors continue to make Hb and other proteins but do not divide properly

Question 9

How to diagnose megaloblastic anaemia?

Answer 9

Bone marrow examination

Question 10

Causes of normocytic anaemia?

Answer 10

Recent blood loss - trauma, gastrointestinal bleed
Failure of production
Pooling of RBC in spleen

Question 11

What is splenic sequestration?

Answer 11

When sickle cells get trapped in the spleen, leading to hyposplenism and the spleen not functioning properly

Question 12

What is polycythemia?

Answer 12

Too many red cells in circulation

Question 13

What causes polycythemia?

Answer 13

Blood doping or transfusions

Increased EPO - can be appropriate or inappropriate

Question 14

What is pseudo polycythemia?

Answer 14

When you have a reduced plasma volume, so it looks like the RBCs take up a larger proportion of the blood colume

Question 15

What causes a reduced plasma volume?

Answer 15

Dehydration

Question 16

What is leukemia?

Answer 16

A cancer arising as a result of a mutation in a precursor of myeloid or lymphocyte cells

Question 17

How is leukemia different to other cancer?

Answer 17

The cells involved circulate in the blood so invasion / metastasis doesn’t apply here

Question 18

What are the four types of leukemia?

Answer 18

Acute Lymphoblastic Leukemia
Chronic Lymphocytic Leukemia
Acute Myeloid Leukemia
Chronic Myeloid Leukemia

Question 19

What does acute mean in the context of leukemia?

Answer 19

Profound pathological affects, fatal in days

Question 20

What does chronic mean in the context of leukemia?

Answer 20

Takes years to be fatal

Question 21

What genes are mutations in to cause leukemia?

Answer 21

Proto-oncogenes and tumour suppressor genes

Question 22

What are the three I’s of leukemic clones?

Answer 22

Immortal, independent and immature

Question 23

What does the abnormal behavior of leukemia clones include?

Answer 23

growth without the need for growth factors
Proliferation without maturation
Failure to undergo normal cell death

Question 24

What are some causes of leukemogenic mutations?

Answer 24

Irradiation eg X Rays
Chemicals eg Benzene
Anti cancer drugs
Cigarette smoke

Question 25

What is the difference between AML and CML?

Answer 25

In AML - there is failure of production of end cells | In CML - there is too much production of end cells

Question 26

What happens in AML?

Answer 26

There is too many immature myeloblasts in the bone marrow - cells continue to divide but cannot nature. Failure of production of end cells like neutrophils, basophils etc

Question 27

What happens in CML?

Answer 27

Too many mature cells end cells - reduced apoptosis so end cells do no die

Question 28

What is hepatomegaly?

Answer 28

Increased liver size

Question 29

What disease characteristics does leukemia lead to?

Answer 29

Enlarged liver, enlarged spleen (splenomegaly), lymphomegaly (enlarged lymph nodes), thymic enlargement (if lymphoid leukemia)

Question 30

What is thrombocytopenia?

Answer 30

Lack of platelets - can arise from leukemia

Question 31

What mutation causes CML?

Answer 31

Translocation between chromosome 9 and chromosome 22, forming the BCR-ABL1 gene which gives the cell a growth and survival advantage

Question 32

What happens in CML?

Answer 32

Increase in ALL GRANULOCYTES and their precursors = splenomegaly

Question 33

What can CML be inhibited by?

Answer 33

Specific tyrosine kinase inhibitors - inhibits the tyrosine kinase which the BCR-ABL1 protein makes which stops the bone marrow from making abnormal cells

Question 34

What is ALL?

Answer 34

Acute lymphoblastic anaemia - replacement of normal bone marrow cells with lymphoblasts

Question 35

What can ALL cause?

Answer 35

Thrombocytopenia, anaemia

Question 36

Which leukemia occurs more commonly in children?

Answer 36

ALL

Question 37

How to treat ALL?

Answer 37

Supportive - give them the cells they are missing | Chemithearoy

Question 38

An aspiring bodybuilder repeatedly takes steroid injections during his training for a competition. What could occur as a result? And why?

Answer 38

Polycythaemia - repeated steroid injections increase testosterone levels which acts on the kidney to increase erythrocyte production, leading to polycythaemia

Question 39

What can increase the risk of leukaemia?

Answer 39

Increased chromosomal breaks, inability to repair DNA normally

Question 40

What are some identifyable causes of leukaemogenic mutations?

Answer 40

Irradiation Anti-cancer drugs Cigarette Smoke Chemicals eg benzene

Question 41

In Chronic Myeloid Leukaemia, cells become independant of external signals. What affect does this have?

Answer 41

There are changes seen in the interactions with the stroma and reduced apoptosis

Question 42

What types of genes are affected to cause chronic myeloid leukaemia?

Answer 42

Genes encoding proteins in signalling pathways between a cell surface receptor and the nucleus eg membrane receptor

Question 43

Why is there a build up of immature cells (myeloblasts) in the bone marrow and in the blood?

Answer 43

Cells continue to proliferate but no longer mature

Question 44

Mutations in what genes usually cause Acute Myeloid Leukaemia?

Answer 44

Mutations in transcription factors for multiple genes causing profoundly disturbed cell behaviour

Question 45

What are the haematological features of Acute lymphoblastic Leukaemia?

Answer 45

Thrombocytopenia, replacement of normal bone marrow cells by lymphoblasts, neutropenia, normochromic and normocytic anaemia

Question 46

What are five supportive treatments for acute lymphoblastic leukaemia?

Answer 46

red cells, platelets, antibiotics, intrathecal chemotherapy, systematic chemotherapy