Antibody-coated bacteria as an indicator of the site of urinary tract infection in renal transplant recipients receiving immunosuppressive agents

Differentiation of upper and lower urinary tract infections: how and when?

The principal purpose of differentiating upper and lower urinary tract infections is to prevent renal damage by determining which patients require long-term antibiotic treatment and follow-up. This article takes a critical look at the method now in use for differentiation of these infections. Special attention is given to the problems of locating a urinary tract infection in a child, both because this is exceptionally difficult in this population and because kidney infections in children carry a high risk of permanent damage including renal failure and hypertension.

[Transplant pyelonephritis (author's transl)]

Examinations of the urine in 216 kidney allograft recipients resulted in significant bacteriuria in 274 samples of 1,802 urines tested. Bacteruria was found in 30 patients with recurrent or chronic persistent infections of the urinary tract; this patient group was studied by examination of 399 urine samples (mean 13.3 samples per patient). Four patients suffered from urologic complications after kidney grafting and were excluded from the study; 15 patients were diagnosed clinically and/or histologically with transplant pyelonephritis, 11 patients with cystitis. Of main importance for the diagnosis of transplant pyelonephritis were findings of persistent leucocyturia and the presence of antibody-coated bacteria. Both of these findings were repeatedly seen in all patients with transplant pyelonephritis. Clinical symptoms included fever and dysuria. In contrast to patients suffering from cystitis, transplant function detoriated in 13 of 15 patients with transplant pyelonephritis; two patients had to be treated by hemodialysis. Septicemia occurred in eight of the 15 patients studied. The data illustrate the frequency of transplant pyelonephritis as observed in 15 of 26 patients accompaining chronic urinary tract infection after kidney allograft transplantation. As a predisposing factor, obstruction of the urinary tract was diagnosed in eight of the 15 transplant recipients with pyelonephritis. The prednisone dose was higher than 10 mg in eight of 15 patients at the time transplant infection was diagnosed. Successful antibiotic treatment resulted in stable transplant function in three patients; four patients exhibited even lower serum creatinine levels after therapy.

A critical review of the antibody-coated bacteria test

Reports extolling the virtues of the antibody-coated bacteria immunofluorescent test continue to appear and therapeutic decisions are being made on the results of this test. In this review 2 unresolved issues are examined: 1) what constitutes a positive test and 2) how accurately does the antibody-coated bacteria test define the tissue source of infection. These issues should be resolved before all clinicians and researchers jump on the antibody-coated bacteria test bandwagon.