Had urine culture three weeks ago showed no growth had another one last week it showed yeast infection why do both show high levels of wbc ?

Leukocytes in urine: WBCs are present in response to almost any form of inflammation. It sounds as if you have a UTI if the urine was collected by a clean midstream catch. If not, the yeast may have present in the urine through contamination from the vaginal secretions and if you have Candida vulvovaginitis that is probably the explanation. Hope this helps.