Localization of the site of urinary tract infections with the bladder washout test

The data from 100 bladder washout studies on pediatric patients have been analyzed to derive criteria for interpretation of this test and to define the limitations of this procedure in localization of the site of urinary tract infections. Using the bladder washout test, infection of the upper urinary tract is characterized by an abrupt increase in the concentration of bacteria in urinary specimens collected following urinary bladder sterilization. Infection limited to the lower urinary tract is characterized by scant if any bacterial growth in the specimens of urine collected following bladder sterilization. The site of infection may be incorrectly localized to the lower urinary tract or classified as not determined in patients with scant or intermittent renal bacteriuria.