Pyuria exists when there is presence of pus (white blood cells) in the urine—most typically caused by a urinary tract or kidney infection. The primary symptoms of pyuria are cloudy and/or foul smelling urine and it can only be detected via a microscopic urine examination (called a urinalysis). There are many medications on the market available to successfully treat pyuria—however the outcome will depend on the underlying cause as to why the condition exists in the first place.