Significance of anaerobic bacteria isolated from the urinary tract. I. Clinical studies

Urinary tract and genito-urinary suppurative infections due to anaerobic bacteria

Anaerobes have been involved in many different types of urinary tract infection. This review describes the microbiology, diagnosis and management of urinary tract and genito-urinary suppurative infections caused by anaerobic bacteria. The types of infections of the urinary tract in which anaerobes have been involved include para- or periurethral cellulitis or abscess, acute and chronic urethritis, cystitis, acute and chronic prostatitis, prostatic and scrotal abscesses, periprostatic phlegmon, ureteritis, periureteritis, pyelitis, pyelonephritis, renal abscess, scrotal gangrene, metastatic renal infection pyonephrosis, perinephric abscess, retroperitoneal abscess and other infections. The anaerobes recovered in these studies were Gram-negative bacilli (including Bacteroides fragilis and pigmented Prevotella and Porphyromonas sp.), Clostridium sp., anaerobic Gram-positive cocci and Actinomyces sp. In many cases, they were recovered mixed with coliforms or streptococci. The recovery of anaerobes requires the administration of antimicrobial therapy that is effective against these organisms. These antimicrobials include metronidazole, chloramphenicol, clindamycin, a carbapenem, cefoxitin and the combination of a penicillin and a beta-lactamase inhibitor. Percutaneous drainage, open surgical drainage or nephectomy might be indicated for abscesses.

The role of anaerobic bacteria in the pathogenesis of urinary tract infections

Because of the rarity of anaerobic infections of the urinary tract and the difficulty of establishing these organisms as pathogens, anaerobic culture is not included as part of routine urine bacteriological examination. Pyuria was found during examination of a 41-year-old man with a chronic renal allograft rejection reaction. Aerobic urine cultures failed to yield any pathogens. Urine cytology demonstrated intracellular organisms that proved to be Fusobacterium nucleatum on anaerobic culture. The serotypically identical organism was isolated from a needle biopsy specimen of the renal allograft. In the presence of pyuria the finding of micro-organisms in the urine sediment that fail to grow on routine aerobic cultures should lead to examination for anaerobic bacterial infection of the urinary tract.

Urinary tract infection caused by anaerobic bacteria in children

Anaerobic bacteria were recovered from 5 children with urinary tract infection (UTI). Three had pyelonephritis and 2 cystitis. Two of the patients had a history of prior recurrent UTI. Urine samples were collected using suprapubic aspiration. The anaerobic organism recovered were 3 isolates of Bacteroides fragilis and one each of B. melaninogenicus, Peptococcus asaccharolyticus, and Bifidobacterium adolescentis. Mixed infection was present in 3 children. In 2 cases B. fragilis were present with Escherichia coli, and in the other case two anaerobes were present. All patients were treated with antimicrobial agents for ten to fourteen days and responded well to therapy. Two of the children had a recurrence of UTI with aerobic organisms recovered from their urine within six to eight months. This report demonstrates the association of anaerobic organisms with UTI in children. It is suggested that cultures for anaerobic organisms be performed in symptomatic children whose aerobic cultures show no bacterial growth.

Peptococcla urinary tract infection with bacteremia: a case report

The second documented case of urinary tract infection with associated bacteremia of Peptococcus asaccharolyticus origin is reported. High fever and low peripheral white blood count were manifestations of bacteremia with Pepococcus asaccharolyticus, an anaerobic gram-positive coccus. Although anaerobes have been documented to cause urinary tract infections resulting in bacteremia most previous reports implicate aerobes in these processes. The problems inherent in culturing urine for anaerobes are reviewed.

Anaerobic urinary infections: Bacteroides fragilis bacteremia from the urinary tract

A case is reported of Bacteroides fragilis bacteremia from an obstructed upper urinary tract. Although anaerobic bacteria rarely cause significatn urinary tract infection it may occur, particularly in the presence of obstruction. The urinary tract must be considered a possible site for anaerobic infections.

Anaerobic urinary tract infection owing to Bacteroides fragilis in a chronic hemodialysis patient

A chronic maintenance hemodialysis patient with severe oliguria and persistent anaerobic urinary tract infection owing to Bacteroides fragilis is presented. Review of the literature shows that the incidence of anaerobic pathogens in random urine cultures is high but that the incidence of clinically significant infection is low. Since the urethra harbors anaerobic organisms suprapubic aspiration of urine and culture are indicated to confirm true anaerobic urinary tract infection. Anaerobic infections are associated with urinary tract abnormalities and pyuria. The various therapeutic maneuvers that were used to treat the infection are discussed, including antibiotic instillation into the bladder and nephrectomy.

Anaerobic bacteriuria in renal transplantation

Renal allograft recipients were studied prospectively utilizing improved culture techniques to investigate anaerobic bacteriuria. The study population was compared with a population of patients with chronic renal insufficiency and end stage renal disease. The over-all incidence of anaerobic urinary tract infection was 7.5 per cent while the over-all incidence of aerobic urinary tract infection was 23.5 per cent. Patients with cadaver renal transplants during the early postoperative period had the highest incidnece of both anaerobic (42.9 per cent) and aerobic (71.4 per cent) urinary tract infection of all groups. The potential association between significant anaerobic bacteriuria during the first postoperative month and poor prognosis for cadaver renal allografts merits further investigation.