A 78 year old man presented after a fall resulting in a bruised hip.
His Full blood count is the following:
Test |
Value |
Normal Range |
Hb |
120 G/L |
115 – 165 |
WBC* |
1.91 x 10^9/L |
3.50 – 11.00 |
PLT* |
28 X10^9/L |
150 – 450 |
RBC* |
3.01 X10^12/L |
3.80 – 5.80 |
HCT* |
0.358 |
0.37 – 0.47 |
MCV* |
118.9 fL |
80 – 100 |
MCH* |
39.9 pg |
26.5 – 33.0 |
MCHC |
335 G/L |
310 – 360 |
NEUTROPHIL 79.6% * |
1.5 x 10^9/L |
1.7 – 7.0 |
LYMPHOCYTE 17.3% * |
0.3 x 10^9/L |
1.5 – 4.0 |
MONOCYTE 3.1% * |
0.06 x 10^9/L |
0.1 – 0.8 |
EOSINOPHIL 0.0% * |
0.00 x 10^9/L |
0.04 –0.44 |
BASOPHIL 0.0% |
0.00 x 10^9/L |
0.00 – 0.20 |
Moderate anisocytosis. Marked macrocytosis.
(a) List four (4) causes for the raised MCV
• B12 deficiency
• Folate deficiency
• Myelodysplastic syndrome
• Therapy with cytotoxics or immunosuppresants
• Alcohol
• Hypothyroidism
• Alcohol and hypothyroidism do not produce such high levels of MCV
usually, but if mentioned answers accepted.
This is another one of those "how many causes of macrocytosis can you list" questions.
To arm the candidate for such questions, a master list of differentials has been created, and it can be found in the chapter dedicated to blood film abnormalities.
To simplify revision, I reproduce the table below:
There are several common causes:
There are also a few uncommon causes:
One can find a discussion of the many causes of macrocytosis in this article.
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.