What does differential wbc count have to do with infection? what would the results be if i had a kidney infection?

Here is...: In response to bacterial invasion to body, immu-sufficient persons will have elevated WBC with higher neutrophils (called shift to left), but not always, such as in the elderly or with low-pressure infected space such as after i ; d, in short, kidney infection is diagnosed by symptoms, physician's high alert... And confirmed with urinalysis and urine culture from properly collected urine specimen.