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 is displayed below:
Parameter |
Patient Value |
Normal Adult Range |
Haemoglobin |
125 q/L* |
130 - 180 |
White Cell Count |
7.4 x 10 /L |
4.5 - 11.0 |
Platelets |
255 x 10 /L |
150 - 400 |
Mean Cell Volume |
110 fl* |
80 - 98 |
Mean Cell Haemoqlobin |
30 oa/cell |
27 - 33 |
Mean Cell Haemoglobin Concentration |
320 g/L |
310 - 360 |
Give six possible causes for the findings on his full blood count. (20% marks)
College answer
Liver disease (including alcoholism)
Folate deficiency B12 deficiency
Hypothyroidism
Myelodysplasia
Drug related (one example required for mark – methotrexate, AZT, trimethoprim, phenytoin, some chemotherapeutic agents, cyclophosphamide. Multiple examples do not gain more marks)
Reticulocytosis
Familial
Discussion
This is macrocytosis, defined as a mean corpuscular volume (MCV) of over 100fl.
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.
One can find a discussion of the many causes of macrocytosis in the 2006 article by Aslinia et al.
References
Aslinia, Florence, Joseph J. Mazza, and Steven H. Yale. "Megaloblastic anemia and other causes of macrocytosis." Clinical medicine & research 4.3 (2006): 236-241.