6. Haematology

Question 1

Where are the sites of haemopoiesis throughout the life of a foetus?

Answer 1

0-2 months - yolk sac
2-5 months - liver and spleen
5-9 months - bone marrow

Question 2

What are the sites of haemopoiesis in an infant?

Answer 2

Bone marrow of most bones.

Question 3

Which bones have bone marrow as a site for haemopoiesis in an adult?

Answer 3

Vertebrae, ribs, sternum, sacrum + pelvis, proximal ends of femur.

Question 4

What is produced in bone marrow?

Answer 4

RBC, platelets, and most WBC.

Question 5

What is bone marrow?

Answer 5

Soft, spongy, gelatinous tissue in the hollow spaces in the interior of bones.

Question 6

What are the two types of bone marrow?

Answer 6

Red marrow and yellow marrow.

Question 7

What does red marrow mainly contain?

Answer 7

Haematopoietic tissue.

Question 8

What does yellow marrow mainly contain?

Answer 8

Fatty tissue.

Question 9

What are the stages of myeloid precursors?

Answer 9

Myeloblast, promyelocyte, myelocyte, metamyelocyte, band cell, neutrophil.

Question 10

What are the stages of RBC precursors?

Answer 10

Proerythroblasts, early normoblast, intermediate normoblast, late normoblast, reticulocyte, RBC.

Question 11

What do megakaryocytes in the BM produce?

Answer 11

Platelets.

Question 12

What is platelet production controlled by?

Answer 12

TPO - thrombopoietin.

Question 13

What does the spleen contain?

Answer 13

Red and white pulp.

Question 14

What is the red pulp in the spleen?

Answer 14

Sinuses lined by endothelial macrophages and cords.

Question 15

What is the white pulp in the spleen?

Answer 15

Similar structure to lymphoid follicles.

Question 16

What is the main source of blood for the spleen?

Answer 16

The splenic artery.

Question 17

What is the role of the white pulp of the spleen?

Answer 17

Screen for infection.

Question 18

What is the role of the red pulp of the spleen?

Answer 18

Sequester RBC that are damaged.

Question 19

What are the functions of the spleen?

Answer 19

Sequestration and phagocytosis, blood pooling, extramedullary haemopoiesis, immunological function.

Question 20

What is extramedullary haemopoiesis?

Answer 20

When pluripotent stem cell proliferate during haematological stress or if marrow fails.

Question 21

What can cause splenomegaly?

Answer 21

Back pressure (portal hypertension), overworking red or white pulp, extramedullary haemopoiesis, infiltrated by cancer cells or other material.

Question 22

What are the causes of massive splenomegaly?

Answer 22

Chronic myeloid leukaemia, myelofibrosis, chronic malaria, Schistosomiasis.

Question 23

What are the causes of moderate splenomegaly?

Answer 23

Chronic myeloid leukaemia, myelofibrosis, chronic malaria, Schistosomiasi, lymphoproliferative disorders, myeloproliferative disorders, liver cirrhosis, infections from EBV.

Question 24

What are the causes of mild splenomegaly?

Answer 24

Chronic myeloid leukaemia, myelofibrosis, chronic malaria, Schistosomiasi, lymphoproliferative disorders, myeloproliferative disorders, liver cirrhosis, infections from EBV or hepatitis or endocarditis, sarcoidosis, AI diseases.

Question 25

What are the risks of splenomegaly?

Answer 25

Risk of rupture.

Question 26

What is hyposplenism?

Answer 26

Lack of functioning splenic tissue.

Question 27

What are the causes of hyposplenism?

Answer 27

Splenectomy, sickle cell disease, coeliac disease.

Question 28

What do hyposplenic blood film show?

Answer 28

Howell Jolly bodies.

Question 29

What are patients with hyposplenism at risk of?

Answer 29

Overwhelming sepsis, particularly from encapsulated organisms.

Question 30

What is cytopenia?

Answer 30

Reduced number of blood cells.

Question 31

What is anaemia?

Answer 31

Low RBC count.

Question 32

What is leucopenia?

Answer 32

Low WCC.

Question 33

What is neutropenia?

Answer 33

Low neutrophils.

Question 34

What is thrombocytopenia?

Answer 34

Low platelets.

Question 35

What is pancytopenia?

Answer 35

Low RBC, WCC, and platelets.

Question 36

What are the causes of immuno thrombocytopenic purpura?

Answer 36

Autoantibodies against GP IIb/IIIa and GPIb/IX; secondary to autoimmune disease e.g. SLE, lymphoma, CLL.

Question 37

How is ITP treated?

Answer 37

Immunosuppression.

Question 38

What are microangiogpathic haemolytic states?

Answer 38

Pathological activation of coagulation causes numerous microthrombi to form in the circulation -> consumption of clotting factors and platelets and haemolytic anaemia.

Question 39

What can reduce production leading to thrombocytopenia?

Answer 39

B12 or folate deficiency, cancer or fibrosis of bone marrow, aplastic anaemia, drugs, viruses.

Question 40

What are the consequences of severe thrombocytopenia?

Answer 40

Easy bruising, petechiae, purpura, mucosal bleeding, severe bleeding after trauma, intracranial haemorrhage.

Question 41

What can reduce production leading to neutropenia?

Answer 41

B12 or folate deficiency, cancer or fibrosis of the bone marrow, aplastic anaemia, radiation, drugs, virus, congenital disorders.

Question 42

What are the consequences of neutropenia?

Answer 42

Severe life threatening bacterial or fungal infection, mucosal ulceration.

Question 43

What can reduce production leading to pancytopenia?

Answer 43

B12 or folate deficiency, cancer or fibrosis of the bone marrow, idiopathic immune aplastic anaemia, radiation, drugs, virus, congenital disorders.

Question 44

What is aplastic anaemia?

Answer 44

Pancytopenia with hypocellular bone marrow in the absence of an abnormal infiltrate with no increase in reticulin.

Question 45

What are the malignancies causing pancytopenia?

Answer 45

Haematological - acute and chronic leukaemia, lymphoma, myeloma, myelofibrosis, myelodysplastic syndrome; non-haematological malignancy - prostate, breast, lung.

Question 46

What are the symptoms of pancytopenia? (Break it down into anaemia, thrombocytopenia, neutropenia).

Answer 46

Anaemia - fatigue, dizziness, chest pain, shortness of breath. Thrombocytopenia - bleeding, bruising etc. Neutropenia - infection, ulcers, fevers.