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Date of last update: 10/12/2017.

Forum Name: Hematology Topics

Question: HELP - microcytosis, anisocytosis 9 month old

 shannonb5 - Mon Mar 17, 2008 6:15 pm

Hi, my name is Shannon and I am writing about my 9 month old son. HE was born three weeks eary with a normal vaginal delivery. He has had several ear infections, but he is otherwise healthy. He is in the tenth percential for height and weight.
He has been sick for a couple of weeks. I took him to the Dr a week and a half ago and was told he had a virus (had been running a low grade fever for a couple of days). 5 days later his temp spiked to 104. Took him back to the Dr and he had double ear infections and toncilitis. Started Augmentin. 2 days later his temp was consistantly above 105. I felt he was dehydrated and took him to the ER. They did a CBC(with manual diff) this is what it showed:

wbc: 35.3
rbc: 4.9
hgb: 10.9
hct: 32.8
mcv: 69
mch: 22.8
mchc: 33.2

rdw: 18.5
plt: 497
seg: 54
bands: 3
lymph: 28
mono: 10
aty lymph: 5

I did a repeat cbc today(3 days later).

wbc: 14.6
rbc: 4.9
hgb: 11.2
hct: 33.9
mcv: 69
mch: 22.9
mchc: 33.2
rdw: 18.5
plt: 466
neutrophils: 11
bands: 1
lymphocyts: 74
monocyts: 4
eosinophils: 4
atyplymphs: 6
anisocytosis: moderate
poikilocytosis: slight
microcytosis: moderate

Also did ferritin: 88.5
I talked to the nurse to day and she said everything was just fine. I am concerned about the RBC and their changes.

Should we be concerned and get a second opinion?
 Dr. Chan Lowe - Tue Mar 18, 2008 7:04 pm

User avatar Hello Shannon,

There are a few things to cover here. First, his initial WBC count is quite high; however, since it dropped back down on the next test, the initial elevated white count was likely due to something called a leukemoid reaction. Basically this is where the body responds to an infection so dramatically that it increases the WBC count into the range commonly seen with leukemia (hence the name leukemoid). This is NOT due to a cancer and is really a harmless thing.

Now, regarding the microcytosis and anisocytosis. Microcytosis means small red blod cells. This correlates with an MCV (mean cell value) of 69 (low). Anisocytosis means the red blood cells are of varying sizes. This corresponds to the RDW (red cell distribution width) that is elevated.

The most common cause of an elevated RDW and a low MCV is, by far, iron deficiency. I would suggest you talk with your son's pediatrician about some iron supplementation to help rebuild his stores. After 2-3 months of iron supplementation, I suspect the MCV will be normal and the RDW will have decreased back to normal as well.

There are a few other possible causes but iron deficiency is much, much more common so trying to correct this is the first step. If there is doubt as to whether or not this is from iron, iron levels can be measured. This is done by testing basically three things-iron level, ferritin level, and total iron binding capacity (or sometimes transferrin saturation instead of the TIBC). Iron deficiency has low iron levels, generally low ferritin levels (although this can be affected by other things), and a high TIBC or low transferrin saturation.

Best wishes.

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