Diagnostic Evaluation
The diagnosis of UTI depends on a high degree of suspicion, evaluation of the history and physical examination, and urinalysis and culture. Urine with a possible infection appears cloudy, hazy, or thick with noticeable strands of mucus and pus; it also smells fishy and unpleasant, even when fresh. A presumptive UTI diagnosis can be made on the basis of microscopic examination of the urine, which often reveals pyuria (5 to 8 white blood cells/ml of uncentrifuged urine) and the presence of at least one bacterium in a Gram stain. However, a normal urinalysis may also be present in conditions of asymptomatic bacteriuria.