[Antibody-coated bacteria and localization of urinary tract infection]

The distinction between upper and lower urinary tract infection (UTI) is of great help in the management and treatment of these conditions. The antibody-coating technique was used to investigate urine of patients with nephrostomies, chronic and acute pyelonephritis, chronic and acute cystitis, of male patients with dysuria and significant bacteriuria and of female patients with indwelling catheters. Furthermore this indirect method was compared with FAIRLEY'S direct method for localization of UTI in female patients with indwelling catheters. All tests were positive in patients with nephrostomies and acute pyelonephritis. Out of 19 tests in patients with chronic pyelonephritis, 18 were positive and one negative. Antibody-coated bacteria were present in 4 out of 8 patients with chronic cystitis and in 2 out of 9 patients with acute cystitis. Out of 5 male patients with dysuria and significant bacteriuria, 3 had a positive test. Out of 25 women with indwelling catheters 20 exhibited antibody-coated bacteria in urine and 5 did not. In 9 female patients with indwelling catheters the UTI was localized in the upper tract 5 times by the Fairley technique but 7 times by determination of antibody-coated bacteria. The demonstration of antibody-coated bacteria in the urine is a simple and reliable method of localizing the site of a UTI. False positive results may be observed in patients with indwelling catheters and prostatitis; in both instances there is probably local antibody production and coating of the bacteria. As the test is relatively expensive and time-consuming, it is indicated only in special situations and is not considered a routine screening procedure.