Is It Possible To Have Pus Cell In Urine Of A Child But No Growth In Culture?

Is it possible to have pus cell in the urine of a child but no growth in culture? My 4 years daughter had little bit complain last month during urination; that is why we agve her urine sample for R/E and culture. from this report, pus cell was 10 but no growth in culture report. again last week we gave the urine sample for urine R/E and pus cell was 8. next day we gave urine sample again for R/E and culture both and according to that report her pus cell was 2.34 and no growth in culture report. why it happens? please note that my daughter had UTI once in the year 2013 (when she was 2.5 years old) and twice in the year 2014 (when she was 3.5 years old).