My sister has a white blood cell count of 25- what does that mean in us terms? Is this high?
Are you certain it is 25? Which typre of WBC- there are several- each is to protect us.
Does she have a history of being ill?
How old is she?
If it is 25, yes, that is low. Do you know WHICH wbc's?
There are so many reasons that nobody could tell you why. Her doctor would have to do more bloodwork to see why.
Sorry, but it is not a cut and dry answer.