Controversies in the Diagnosis of Urinary Tract Infections

Urinary tract infection is one of the most commonly encountered infectious diseases in the United States, and urinalysis and urine culture are among the most commonly performed laboratory tests. Despite information in the literature, there continues to be ongoing controversy regarding the appropriate collection method for culture, the utility of urine preservation methodologies, and the work-up of urine cultures containing low numbers of bacteria. We have reviewed the literature to determine optimal specimen collection techniques, the effect of specimen preservation on urine culture results, and the interpretation of low urine culture colony counts.