sudden high wbc, help with lab results

I had posted my recent lab results on the blood forum, but no response. Hoping someone on this forum could give me some insight.

Due to up coming surgery, I had to have blood test taken. Here are the results
9/8/07
HBG 14.7 (11.6-15.0)
HCT 42.8 (35-45)
RBC 4.26 ((4.10-5.7)
RDW 13 (11.5-14.5)
WBC 10.8H (4.5-10.0)
MCV 100.7H (80-96)
MCHC 34.3H (28-34)
Platelet 435H (130-400)
MPV 6.9L (7.4-10)
Neutrophiles# 7.7H (1.85-7.3)

Three days later, I had to have another blood test for another doctor.
9/11/07
WBC16.2H (4-10.5)
RBC 4.38
HBG 15 (11.5-15) at the high end of normal
HCT 44.7H (34-44.7)
MCV 102 H (80-98)
MCHC 34.3 H (27-34)
RDW 13 (11.7-15)
Platelets 361 (140-415)
Neutrophils (absolute) 11.3H ( 1.8-7.8)

So my question is can my wbc go this high just in a few days. I do have a sinus problem, but it was no different when I had the first set of blood test done. Anyone have any ideas what it could be. Been reading, and yes I know that is a dangerous thing, the it could be leukemia or some other cancer. I know if you are sick, your wbc can go up but I did not think it could go up this much from 10.8 to 16.2? Besides the sinus thing, I am feeling fine. I am hypothyroid on meds.

If you have any slight infection, the body's natural repsonse is to "launch" an attack against the infection. This will cause an increase in the WBC. Blood counts will flexuate from day to day. You may find that immediately following an infection, the WBC may fall into the low range, because the immune system has basically pulled out it's arsenals and is in recovery.

All of your other counts, even being on the slightly high side, seem to be within normal range.

A high HGB count can indicate the need for more hydration.

Thanks Jectac for you quick response.

MB