non-megaloblastic macrocytosis (red cell membrane changes)

Question 1

what is it?

Answer 1

a genuine macrocytosis

Question 2

what causes it?

Answer 2

• Alcohol 
• Liver disease 
• Hypothyroidism 
(causes above may not be associated with anaemia)
• Marrow failure (always associated with anaemia)
o	Myelodysplasia 
o	Myeloma 
o	Aplastic anaemia

Question 3

what is spurious macrocytosis?

Answer 3

Volume of the mature red cell is normal but the MCV is measured as high

Question 4

what causes spurious macrocytosis?

Answer 4

An increase in reticulocyte numbers occurs as a marrow response to acute blood loss or red cell breakdown (haemolysis) the reticulocytes are bigger than mature rbc and are analysed wit them for MCV measurement
cold agglutinins - clumps of agglutinated red cells are registered as 1 huge cell