On November 26, I woke with a sharp pain in my lower back, rt side. ER said there was a lot of blood and pus in my urine. Blood test showed WBC at 14,000. Doctor suspected kidney stones and requested a CT scan. CT scan showed no kidney stones, gallstones, etc. (Ovarian cysts were found, but pain is in different area.) Doctor said he assumed kidney infection since he ruled out other things and placed me on a round of antibiotics. He wasn't sure this was the problem because my WBC was only slightly elevated but couldn't find another reason for the pain. My WBC was also slightly elevated one month before during routine bloodwork, but my PCP decided that we would wait and check it again since I had no signs of infection. I took the full course of antibiotics but the back pain has returned. Any ideas?