Does white blood cells always show positive on test strip for uti?

No: The tests strips for uti's are not that accurate. You really need a first morning void and the specimen can be contaminated by vaginal secretions which often have white blood cells in them. Positive nitrites in urine are more suggestive of a urinary tract infection.

No: Yiu can have bacteria without wbc. We call it asymptomatic bacteria. Wbc or white blood cells should not be present in a normal urine specimen. You can, however, see WBC ina number of situations like a contaminated specimen, a non-infectious inflammatory condition, etc.