The site of urinary infection in 51 adult women was determined by the bladder-washout technique (BW). Of the 37 patients with proved upper-tract infection shown by BW, 16 had upper-tract symptoms, three had lower-tract symptoms, and 18 were asymptomatic; 31 had antibody-coated bacteria (ACB), and six had no ACB. Of 14 patients with proved lower-tract infection shown by BW, three had upper-tract symptoms, five had lower-tract symptoms, and six were asymptomatic; none had ACB. All 31 women whose infecting bacteria were coated with antibody proved to have an upper-tract infection shown by BW. A subset of the population of adult women with upper-tract infection have organisms emanating from their ureters at BW localization, which are not coated with antibody. Physicians must be cautious in interpreting results that are negative for ACB.
(JAMA 240:1147-1150, 1978)