Haem: Haematology of Systemic Disease Pt.1

Question 1

List some ways in which lymphoma can cause jaundice.

Answer 1

• Direct liver involvement
• Compression of the bile duct
• Causing autoimmune haemolytic anaemia

Question 2

Which types of anaemia can be cause by cancer?

Answer 2

• Iron deficiency
• Anaemia of chronic disease
• Haemolytic anaemia
• Leucoerythroblastic anaemia

Question 3

Which types of cancer are associated with causing secondary polycythaemia?

Answer 3

• Renal cell carcinoma
• Liver cancer
• Due to the production of EPO

Question 4

What is the most common cause of iron deficiency anaemia?

Answer 4

Occult blood loss (e.g. GI cancers, urinary tract cancers)

Question 5

What are the typical laboratory findings of iron deficiency anaemia?

Answer 5

• Low ferritin
• Low transferrin saturation
• High TIBC

Question 6

What is leucoerythroblastic anaemia?

Answer 6

Anaemia is characterised by the presence of red and white cell precursors

Question 7

What are the morphological features of leucoerythroblastic anaemia seen on blood film?

Answer 7

• Tear drop red blood cells (aniso- and poikilocytosis)
• Nucleated RBCs
• Immature myeloid cells

Question 8

What does leucoerythroblastic anaemia tend to be caused by?

Answer 8

• Bone marrow infiltration (leukaemia, lymphoma, myeloma, solid tumours, myelofibrosis, military TB, severe fungal infection)

Question 9

Define haemolytic anaemia.

Answer 9

Anaemia caused by reduced red blood cell survival

Question 10

List some key laboratory findings in haemolytic anaemia.

Answer 10

• Anaemia
• Raised reticulocytes
• Raised unconjugated bilirubin
• Raised LDH
• Low haptoglobins

NOTE: LDH is an intracellular enzyme that is released when RBCs are destroyed

Question 11

What are the two main groups of haemolytic anaemia? List some examples.

Answer 11

Inherited (defects with the cell)

• Hereditary spherocytosis (membrane problem)
• G6PD deficiency (enzyme problem)
• Sickle cell disease, thalassemia (haemoglobin problem)

Acquired (defects with the environment)

• Immune-mediated
• Non-immune mediated

Question 12

Which test distinguishes immune-mediated and non-immune mediated haemolytic anaemia?

Answer 12

DAT or Coombs’ test

DAT +ve means that the haemolytic anaemia is mediated through immune destruction of red cells

Question 13

What morphological change is seen on the blood film of patients with autoimmune haemolytic anaemia?

Answer 13

Spherocytes

Question 14

List some systemic diseases that can cause autoimmune haemolytic anaemia.

Answer 14

• Cancer involving the immune system (e.g. lymphoma)
• Disease of the immune system (e.g. SLE)
• Infections (disturbs the immune system)

Question 15

List some causes of non-immune haemolytic anaemia.

Answer 15

• Infection (e.g. malaria)
• Microangiopathic haemolytic anaemia (MAHA)

Question 16

List some key features of MAHA.

Answer 16

• Usually caused by underlying adenocarcinoma
• Red cell fragments
• Low platelets
• DIC/bleeding

Question 17

Outline the mechanism of MAHA.

Answer 17

• An underlying adenocarcinoma produces procoagulant cytokines that activate the coagulation cascade
• This leads to DIC and the formation of fibrin strands in various parts of the microvasculature
• Red cells will be pushed through these fibrin strands and fragment

NOTE: always consider underlying adenocarcinoma in any patient presenting with MAHA

Question 18

List some causes of secondary polycythaemia.

Answer 18

• Cancer (renal, hepatocellular, bronchial)
• High altitude
• Hypoxic lung disease
• Congenital cyanotic heart disease