Anaemia and polycythaemia

Question 1

Anaemia classification based on cell size

Answer 1

• Microcytic (usually also hypochromic)
• Normocytic (usually also normochromic)
• Macrocytic (usually also normochromic)

Question 2

Microcytic anaemia causes

Answer 2

-Defect in haem synthesis (iron deficiency anaemia, anaemia of chronic disease)
-Defect in globin synthesis (thalassaemia)
Defect in alpha chain synthesis gives alpha thalassaemia
Defect in beta chain synthesis gives beta thalassaemia

Question 3

Normocytic normochromic anaemia causes

Answer 3

• Recent blood loss (peptic ulcer, oesophageal varices, trauma)
• Failure of RBC production (early stages of iron deficiency or anaemia of chronic disease, renal failure, bone marrow failure/suppression, bone marrow infiltration)
• Pooling of RBCs in spleen (hypersplenism)

Question 4

Autoimmune haemolytic anaemia diagnosis

Answer 4

• finding spherocytes and an increased reticulocyte count
• detecting immunoglobulin +/- complement on RBC surface
• detecting antibodies to RBC antigens or other autoantibodies in plasma

Question 5

Autoimmune haemolytic anaemia treatment

Answer 5

• use of corticosteroids and other immunosuppressants

- if severe=splenectomy

Question 6

Haemolytic anaemia

Answer 6

Anaemia resulting from shortened RBC lifespan in the circulation
-Haemolysis due to intrinsic RBC abnormality or extrinsic factors affecting normal RBCs

Question 7

Intravascular haemolysis

Answer 7

Occurs in blood vessels due to very acute RBC damage

Question 8

Extravascular haemolysis

Answer 8

Occurs when spleen removes defective/abnormal RBCs

Question 9

Inherited haemolytic anaemia

Answer 9

Results from abnormal cell membrane, abnormal haemoglobin or abnormal RBC enzymes

Question 10

Acquired haemolytic anaemia

Answer 10

Results from extrinsic factors (microorganisms, chemicals or drugs that cause RBC damage)

Question 11

Anaemia

Answer 11

• Reduction in the amount of haemoglobin in a given volume of blood below what would be expected in comparison with a healthy subject of the same age and gender
• Hb reduced, with RBC and Hct/PCV usually also reduced

Question 12

Microangiopathic haemolytic anaemia treatment

Answer 12

• Removing the cause (eg: severe hypertension treatment or stopping causative drug etc)
• Plasma exchange (when caused by antibody in the plasma which indirectly leads to fibrin deposition)

Question 13

Autoimmune haemolytic anaemia treatment

Answer 13

• Corticosteroid use and other immunosuppressive agents

- Severe cases require splenectomy (spleen removal)

Question 14

Autoimmune haemolytic anaemia diagnosis

Answer 14

• Finding spherocytes and increased reticulocyte count
• detecting immunoglobin +/- complement on the RBC surface
• detecting antibodies to RBC antigens or other autoantibodies in the plasma