Question 25.2

A 62-year-old male has been admitted to your ICU for routine post-operative monitoring after a vascular surgical procedure.

His pre-operative full blood count (FBC) is displayed below:


Patient Value

Adult Normal Range


125 g/L*

130 – 180

White Cell Count

7.4 x 109/L

4.5 – 11


255 x 109/L

150 – 400

Mean Cell Volume

110 fL*

80 – 98

Mean Cell Haemoglobin

30 pg/cell

27 – 33

Mean Cell Haemoglobin Concentration

320 p/L

310 – 360

a) Give six possible causes for the findings on his FBC.    (30% marks)

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College answer

Not available.


The abnormalities are:

  • A slightly anaemic haemoglobin, for a dude
  • A wildly elevated mean cell volume (i.e. macrocytosis)

The cell haemoglobin content is normal, i.e. this is a macrocytic normochromic anaemia.

There are several common causes:

  • Alcoholism
  • Vitamin B12 deficiency
  • Folate deficiency
  • Myelodysplastic syndromes 

There are also a few uncommon causes:

  • Reticulocytosis
  • Nonalcoholic and alcoholic liver disease
  • Hypothyroidism
  • Multiple myeloma
  • Aplastic anemia
  • Acute leukemia
  • Drugs:
    • trimethoprim, triamterine, nitrous oxide, phenytoin, valproate, chemotherapy agents, HIV antiretrovirals and metformin.


Aslinia, Florence, Joseph J. Mazza, and Steven H. Yale. "Megaloblastic anemia and other causes of macrocytosis." Clinical medicine & research 4.3 (2006): 236-241.

Walker, H. Kenneth, et al. "Peripheral blood smear." (1990). in Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition.