What Causes Severe Itching In The Labia Majora?

hey doctor , Iam Demiana female patient 24 years old , single , at 6 medical school , from Egypt complain from itching in labia majora from 2 weeks duration itching increase after urination and decrease with recurrent washig with water and use ( vagyl ) vaginal antiseptic ... now itching decrease but course intermittent in general i had suffer from UTI from 1 year and 2 month by bacterial and fungal showed by urine test and urine culture , and I had severe itching and buring sensation in urination that s made me cry and received medical ttt and improved and not complain from this time now I have recurrent ithching but from mild to moderate and urine test shoe +ve aceton and pus cell (8-10 hfp) and no organism appear on culture after 48 hrs no history of D.M or HTN or any thing.. now what I can do ?? help me please , thanks in advanced