Localization of the site of urinary tract infections by means of antibody-coated bacteria in the urinary sediments.

A prospective study was conducted in children with urinary tract infections to examine the relationship between the presence of antibody-coated bacteria in the urinary sediments and the presence of pyelonephritis. The site of the urinary tract infection was localized as upper or lower urinary tract by the bladder washout technique. Antibody-coated bacteria in the urinary sediments were identified by an immunofluorescent method. In 4 of 12 children with upper urinary tract infections, less than 1% of the bacteria in the urinary sediments were antibody coated. In 10 of 35 children with lower urinary tract infections more than 50% of the bacteria in the urinary sediments were antibody coated. These studies show no significant correlation between the presence of antibody-coated bacteria in urinary sediments and infection of the upper urinary tract.