Haematology

Question 1

Definition of anaemia

Answer 1

• Low haemoglobin levels in the blood, usually accompanied by low red cell count and packed cell volume.

Question 2

How is oxygen carried round the body?

Answer 2

• Oxygen is carried from the lungs to the tissues by haemoglobin.
• Oxygenation and deoxygenation occurs at the haem iron in the haemoglobin.

Question 3

What affect does anaemia have on the body?

Answer 3

• Low haem levels means less oxygen carried to the tissues leading to tissue hypoxia, this causes a compensatory change in the body that allows increased tissue perfusion and increased production of red cells.
• Ultimately this leads to pathological changes in the body.

Question 4

What is the life cycle of red blood cells?

Answer 4

• Produced in the bone marrow, circulate the body for around 120 days before being removed by the liver, spleen, bone marrow or blood loss.

Question 5

What are the presentations of anaemia?

Answer 5

• Depends on the severity of onset of the symptoms:
• Can be asymptomatic if slow and time for the body to compensate can occur.
• Otherwise presents with non specific symptoms such as fatigue, dizziness and palpitations.
• Skin and mucosal membranes may also be pale.

Question 6

How are anaemias classified?

Answer 6

• Depending the measurement of their red blood cells.

Question 7

What is microcytic anaemia?

Answer 7

• Low Hb and low MCV = small cells

- Caused by iron deficiency, thalassaemia and anaemia of chronic diseases.

Question 8

What is microcytic anaemia?

Answer 8

• Low Hb and high MCV = large cells
• Can either be megaloblastic or non megaloblastic depending on the bone marrow findings.
• Megaloblastic = folate or vitamin B12 deficiencies
• Nonmegaloblastic = alcohol, liver disease, hypothyroidism

Question 9

What is normocytic anaemia ?

Answer 9

• Low Hb and normal MCV

- Caused by acute blood loss or anaemia of chronic diseases

Question 10

Definition of multiple myeloma

Answer 10

• A disseminated bone marrow plasma cell neoplasm associated with serum and/or urine paraprotein
• Lytic bone lesions/ CRAB end organ damage
• Excess plasma cells in the bone
• Usually older adults, mean age around 60 and also male predominance.

Question 11

Presentation of multiple myeloma

Answer 11

• Bone pain and recurrent infections

- Raised ESR, anaemia, hypercalcaemia and renal impairment

Question 12

Investigations of multiple myeloma

Answer 12

• 2 out of 3 of the classic symptoms is diagnostic:
• Electropheresis - identify paraprotein in the urine and serum
• MRI/CT - lytic lesions such as pepper pot skull and vertebral collapse
• Bone marrow aspirate - excess plasma cells

Question 13

Management of multiple myeloma

Answer 13

• Mean survival is 5 years, but some patients can survive 10 years.
• Patients require initial treatment and then supportive therapy.
• It remains incurable but younger patients with more intense initial treatment and agents to continue suppression prolong survival.

Question 14

What are lymphomas?

Answer 14

• B and T cell malignancies that are more common than leukemias.
• They can be classified as Hodgkin’s or Non Hodgkin’s
• Basically malignancies of the white blood cells, most commonly seen in lymph but can be anywhere.

Question 15

Hodgkin’s Lymphoma

Answer 15

• Usually seen in young adults (15 to 35)
• Possible causes includes EBV
• Crippled B cell neoplasms B cells - Reed Sternberg cells.
• More common in men than women
• Presents as painless lymph node enlargement - usually rubbery on examination and also systemic features such as fever, night sweats and weight loss ( More than 10% in the past 6 months)
• Investigations include lymph node biopsies to confirm the Reed Sternberg cells.
• Management is of a curative nature, combo of chemo and irradiation depending on the staging of the cancer.

Question 16

Non Hodgkin’s Lymphoma

Answer 16

• Malignancies of all other B cells that aren’t Reed Sternberg.
• Rarely seen in patients below the age of 40.
• Presents again as painless peripheral lymph node enlargement as well as systemic features, more likely to involve other organs of the body than Hodgkin’s.
• Lymph node biopsy is diagnostic with similar management to Hodgkin’s.

Question 17

What are leukemias?

Answer 17

• Malignancies about haemopotin cells.
• Characterised by diffuse replacement of bone marrow with the malignant cells.
• Most commonly caused by drugs, chemo, radiation leading to genetic changes, viruses or genetic factors.

Question 18

What are the acute leukemias?

Answer 18

• Can either be acute lymphblastic leukemias (young children between 3 and 7) or acute myeloid leukeumias (older patients both middle age and elderly adults).
• Characterised by accumulation of the cells within the bone marrow, peripheral blood and other tissues.
• Leads to a reduction in red bloods cells, platelets and neutrophils.
• Patients present with anaemia, infections, bleeding, peripheral lymphodenopathy and splenomegaly
• Investigations include peripheral blood films, bone marrow aspirate and lymph node biopsies.
• Management is about initial chemo and then inducing remission.

Question 19

What is chronic myeloid leukemias?

Answer 19

• Characterised by the uncontrolled proliferation of myeloid cells.
• Most commonly in middle aged patients with Ph chromosomes, slight male predominance.
• Presents with insidious onset of fever, weight loss, night sweats, anaemia. Masssive splenomegaly is characteristics.
• Investigations about bone marrow aspirate and management is using Imatub in chronic phase and chemo in acute phase.

Question 20

What is chronic lymphcytic leukemias?

Answer 20

• Chracterised by the uncontrolled proliferative and accumulation of mature B lymphocytes.
• Most common, incurable
• Presentation can be asymptomatic or with bleeding, anaemia, infections.
• Investigations include blood films showing ‘smudge or smear’
• Management about inducing remission.

Question 21

What are haemoglonopathies?

Answer 21

• Sicke cell disease - crest shaped blood cells leading acute crisis and chronic complications.
• Thalassaemia

Question 22

What is thalassaemia?

Answer 22

• In normal Hb, there is a balance of alpha and beta chains.
• In thalassaemia there is one or more genetic mutations that lead to imbalance in the production of alpha and beta cells, this means there is cell damage, death of red cell precursors in the bone marrow and haemolysis.

Question 23

What is beta thalassaemia?

Answer 23

• Little or no production of beta chains and overproduction of alpha chains.
• Presents with anaemias of varying degrees.
• Hb electropheresis showing increased in Hb F and no Hb A, blood count and film needed.

Question 24

What is alpha thalassaemia?

Answer 24

• Ranges from very mild anaemia to presentation incompatible with life.
• Depends how many chains are present.

Question 25

What is thrombocytopenia?

Answer 25

• Low platelet levels

Question 26

How are platelets produced?

Answer 26

• Produced in the bone marrow and are fragments of megakaryocytes.

Question 27

How is thrombocytopenia caused?

Answer 27

• Could be due to failure to produce platelets such as congenital causes include VWD or acquired due to drugs, marrow suppression ec.
• Could be due to increased removal (immune, consumption or splenomegaly)

Question 28

Presentation of thrombocytopenia

Answer 28

• Mucosal bleeding such as gum bleeding, epistaxis or mennorgegia, easy bleeding, petechiae, purpura and traumatic haematomas.

Question 29

ITP

Answer 29

• Immune destruction
• Usually seen in children post viral infection, can relapse in later life and is less acute in adults.
• Presents with rapid purpura
• Management is with oral corticosteroids, immunusprpressive agents and IV iG agents.

Question 30

TTP

Answer 30

Due to ADAMT 13