Posted 1/27/2015 6:28 PM (GMT 0)
A cbc will just measure your red blood cells, white blood cells and platelets (parts that clot your blood). It can be done to measure any one of those. I would imagine, since your doctor suspects a sinus infection, she wants to see how your immune system is responding. White blood cells will show if you have an infection. I know you're worried, but it is a very routine and nothing to worry about. Thinking of you!