One has to be careful in interpreting the urine analysis. To be accurate it has to be a clean mid-stream urine specimen. This may be difficult to collect at times.
What happens very often is the urine will pick up White blood cells which are part of a vaginal discharge and gives the false impression that it is a urinary tract infection.
A specific test for vaginal infection must be done if there is an associated abnormal vaginal discharge. The Trichomoniasis comes from the vagina rather than from the bladder.