Im not a doctor either but could it be that this is a healing reaction? Understand that the white blood cell has a cancer, a microbe within it that is making him ill. Could it be that this increase is due to a whole new batch of healthy white blood cells?
If it were me I'd be having my blood analized by Dark Field Live Blood Analysis available from some naturopaths and some alternative minded medical doctors. This way you will really know what is going on in the blood.
Please read my article on this type of blood analysis here:
www.healthsalon.org/586/live-blood-analysis-by-dark-field-microscope/
This link might help you to find a doctor who does this work, elsewise you will just have to call all the alternative folks you can find until you find someone who does it.
www.healthsalon.org/421/ozone-practitioners-found-in-the-usa/
also, could it be a lab error? Labs do make mistakes you know.