Blood films

Question 1

What are acanthocytes?

Answer 1

Spikes on RBCs due to unstable membrane

Caused by splenectomy, alcoholic liver disease, abetalipoproteinemia and spherocytosis

Question 2

What is anistocytosis?

Answer 2

Variation in RBC size

Question 3

Basophilic RBC stipling

Answer 3

Denatured RNA found in RBCs indicating accelerated erythropoesis or defective Hb synthesis.

Seen in lead poisoning, megaloblastic anaemia, myelofibrosis and malignant marrow infiltration

Question 4

What are blasts in a blood film?

Answer 4

Nucleated precursor cells that should not normally appear in the peripheral blood film but do in leukaemia, myelofibrosis and malignant marrow infiltration

Question 5

What are cabot rings?

Answer 5

Seen in pernicious anaemia, lead poisoning and bad infections

Question 6

What are burr cells/ echinocytes?

Answer 6

RBC projections, less marked than acanthocytes

Question 7

What are Howell-Jolly bodies?

Answer 7

DNA nuclear remnants in RBCs which are usually removed by the spleen, seen post splenectomy and in hyposplenism

Question 8

What is a leukoerythroblast film?

Answer 8

Immature cells ± tear drop RBCs from haemolysis or marrow infiltration

Question 9

What are pappenheimer bodies?

Answer 9

Granules of siderocytes containing iron

Question 10

What is poikilocytosis?

Answer 10

Variation in RBC shape

Question 11

What is olychromasia?

Answer 11

RBCs of different ages stain differently - young cells are more blue

Question 11

What is rouleaux formation?

Answer 11

Stacks of RBCs, caused by infections, multiple myeloma, Waldenstrom’s macroglobulinemia, inflammatory and connective tissue disorders, and cancers. It also occurs in diabetes mellitus and is one of the causative factors for microvascular occlusion in diabetic retinopathy

Question 12

What are schistocytes?

Answer 12

Fragmented RBCs - formed by mechanical destruction of RBCs by fibrin bands following clot formation

Question 13

What is neutrophilia?

Answer 13

Increased neutrophils

• Bacterial infections
• Inflammation
• Steroids

Question 14

What causes neutropenia?

Answer 14

• Viral infections
• Drugs
• Severe sepsis
• Hypersplenism
• Smoking

Question 15

What causes lymphocytosis (increased lymphocytes)

Answer 15

• Leukaemia and lymphoma (especially CLL)
• EBV
• Chronic infections e.g. TB

Question 16

What is hypereosinophilic syndrome?

Answer 16

Raised eosinophils for >6weeks, leads to organ damage

Treated with imatinib

Question 17

What is the function of a neutrophil?

Answer 17

Bacterial or fungal infection

Most common first responders to microbial infection

Question 18

What is the function of an eosinophil?

Answer 18

Parasitic infections and allergic reactions

Question 19

What is the function of basophils?

Answer 19

Allergic and antigen response (release histamine causing vasodilation)

Question 20

What is the function of lymphocytes?

Answer 20

Subtypes of white blood cell

Includes B cells, CD4+ T helper cells, CD8+ cytotoxic T cells

Primarily operate in the lymphatic system

Question 21

What is the function of monocytes?

Answer 21

Phagocytosis of pathogens, presentation of antigens to T cells

Eventually become tissue macrophages

Kidney shaped nucleus

Question 22

Which WBCs have bi or tri-lobed nuceli?

Answer 22

Basophils

Question 23

Which WBCs have multi-lobed nuclei?

Answer 23

Neutrophils

Question 24

What is haematopoiesis?

Answer 24

Production of the blood

Question 25

Where does haematopoiesis most commonly occur in adults?

Answer 25

Bone marrow AKA medullary haematopoiesis

Question 26

What is extra-medullary haematopoeisis?

Answer 26

Haematopoiesis that occurs outside of the bone marrow e.g.liver, thymus and spleen

Question 27

Which bones are the most common sites of haematopoiesis?

Answer 27

Flat bones - Pelvis - Cranium - Sternum - Vertebrae

Question 28

Where does haematopoiesis occur in children?

Answer 28

Marrow of the long bones e.g. tibia and femur

Question 29

Where does haematopoiesis occur before birth?

Answer 29

Liver (mainly) and spleen

Question 30

What causes an increase in extramedullary haematopoiesis?

Answer 30

Infection - can promote liver, spleen and LNs to take part in haematopoiesis because of the need for more blood Hence hepatomegaly and splenomegaly during periods of infection

Question 31

What do haematopoietic stem cells differentiate into?

Answer 31

1. Common lymphoid progenitor cells 2. Common myeloid progenitor cells

Question 32

What cells do common lymphoid cells differentiate into?

Answer 32

Lymphoblasts - become lymphocytes Large lymphocytes = natural killer cells Small lymphocytes = T and B cells

Question 33

Where do plasma cells come from?

Answer 33

B cells

Question 34

What do common myeloid progenitor cells differentiate into?

Answer 34

- Myeloblasts e.g. neutrophils, eosinophils, basophils and monocytes - Megakaryocytes (in response to thrombopoietin from the liver and kidneys) - Erythroblasts (in response to EPO from the kidneys)

Question 35

Where do platelets come from?

Answer 35

Budding of megakaryocytes

Question 36

What appears on a full bloof count?