I recently had been having this left side pain. It was this stabbing and throbbing pain i have never felt in my life. I finally took a uti strip test and it tested negative for nitrates but positive for white blood cells. I finally went to the hospital after not being able to take the pain. They took blood and urine for testing. The urine had no trace of blood and they said my white blood cells where fine. which didnt indicate infection. why was this???? and where was this left side pain coming from???? They said the possability of a kidney stone would be rare but possible. Sent me home with back pain and told me if the pain continued to come back and they would do a ct to see if a kidney stone may be present. But why was the test i did positive for white blood cell??