Urinary tract infection after renal transplantation

Bacteriuria and urinary infections in the elderly

Aging is associated with a decreased physiological functioning, reflecting the body's progressive inability to maintain homeostasis as age increases. The physiologic dysfunctions experienced in response to the aging process increase the individual's susceptibility to infection. Many elderly subjects are hospitalized for the care and treatment of functional disabilities; thus, an increased exposure to possible uropathogens (many with antimicrobial resistance) often results in infection. Additionally, indwelling catheters and other attending procedures may provide a microenvironment conducive to infection. In catheterized patients, the drainage bag often is infected with polymicrobes, which enhances the transference of antimicrobial genetic information. Postmenopause reflects a decrease in circulating estrogen, and a relational decrease in lactobacilli colonization with a lower vaginal pH. Consequently, vaginal colonization with possible uropathogenic and gastrointestinal bacteria increases, which partially may account for the generally higher incidence of bacteriuria in elderly women as opposed to elderly men. Urinary infections in the elderly more commonly are asymptomatic. Treatment for asymptomatic bacteriuria is not justified and will often present opportunities for the infecting organism to acquire antimicrobial resistance. Only symptomatic bacteriuria presenting adverse conditions in the host should be treated. Antimicrobial selection for the treatment of complicating symptomatic urinary infections in elderly subjects is complicated by the many physiological and environmental conditions associated with older age patients. Unfortunately, data confirming the efficacy and safety of antimicrobial agents for the treatment of symptomatic infections in the elderly presently are insufficient.

Congenital immunodeficiencies in mice increase susceptibility to urinary tract infection

Severe combined immunodeficient (SCID), T cell deficient, and immunocompetent mice were challenged intravesically with viable uropathogenic Escherichia coli. In comparison to immunocompetent controls, SCID mice had significantly greater numbers of viable E. coli in their bladders and kidneys 7 days after inoculation. Splenic anti-E. coli antibody-forming cells (AFC) were virtually absent in SCID mice at 7.0 days after infection. Adoptive transfer of spleen cells from E. coli-immunized immunocompetent mice to SCID mice enhanced their resistance to urinary tract infection (UTI), as evidenced by lower bacterial counts in bladder and kidneys following an induced infection. Congenitally T cell deficient nude mice and immunocompetent heterozygous controls had equivalent bladder and kidney infection levels at 2 and 7 days after UTI. Immunocompetency thus appears to play a significant role in resistance to E. coli UTI in this animal model. Since mice deficient only in T cells did not show increased UTI susceptibility, T cell-independent antibody responses may be an important immunologic defense mechanism.

Long-term clean intermittent self-catheterization in renal transplant recipients

Eight renal transplant recipients with neurogenic bladders or lower urinary tract dysfunction were managed with clean intermittent self-catheterization after transplantation instead of urinary diversion. A total of 85 treatment months was reviewed. Of the patients 5 continue to do well after 10 to 17 months of intermittent catheterization and 3 suffered immunological graft failures. In selected renal transplant recipients with lower urinary tract dysfunction clean intermittent catheterization is a reasonable alternative to urinary diversion.

Urinary tract infection in boys

Considerable literature exists regarding the evaluation and treatment of children with urinary tract infection yet little has been reported solely about boys. We reviewed retrospectively 83 boys who were seen after an initial urinary tract infection. Fever was the most common presenting sign (50 per cent) and the most common organisms encountered were of the gram-positive group of bacteria. Escherichia coli accounted for only 21 per cent of the infections. Of the boys 75 per cent (62 patients) had an anatomic abnormality, most commonly vesicoureteral reflux, although more than 25 per cent of our patients had obstructive lesions. Renal scarring was present in half and 58 per cent required early surgical intervention. Urinary tract infection seems to have a higher morbidity in boys and the finding of an atypical organism is to be expected. Based on our findings, we strongly recommend an excretory urogram and a voiding cystourethrogram as the minimal evaluation of boys following an initial urinary tract infection.

Urinary tract infection in pediatric renal transplantation

Urinary tract infection is a frequent complication following renal transplantation and represents a potential focus for systemic infection in the immunosuppressed transplant recipient. The incidence, etiologic factors, temporal pattern, bacteriology, and prognostic significance of urinary tract infection were determined by analysis of 85 renal allografts in 69 patients. Significant bacteriuria occurred after 49 of 85 transplants (58 per cent). The incidence of infection was not related to success or source of the allograft, but was related to patient gender. Urinary tract infections developed in 68 per cent of females, while only 43 per cent of males became infected (p less than 0.05). Escherichia coli caused most first infections (30 per cent), while Pseudomonas aeruginosa and E. coli were equally responsible for recurrent infections (25 per cent each). Children with previous reconstructive urologic surgery had similar allograft success (63 per cent) and infection rates (53 per cent) as our other children (61 per cent and 58 per cent, respectively). No apparent correlation was noted between episodes of infection and graft rejection. Thorough preoperative assessment and preparation and prompt, specific treatment minimize the adverse influences of urinary tract infection.

Post-transplantation pyelonephritis: factors producing low patient and transplant morbidity

A retrospective study of 1,100 consecutive renal transplantations done on 959 patients revealed postoperative pyelonephritis in 15 patients, 14 of whom were women. Sixteen of the 20 episodes of pyelonephritis were caused by Escherichia coli and only 4 episodes occurred within the first year after transplantation, thus revealing the crucial differentiation from a rejection episode. When the etiology of the original renal failure was pyelonephritis the incidence of pyelonephritis in the transplanted kidneys was high. This high incidence also was true for cases associated with post-transplantation urological complications. When the etiology of renal failure was diabetes or polycystic renal disease, or when urologic abnormalities pre-existed the incidence of pyelonephritis was low. No transplant or patient loss was caused by post-transplantation pyelonephritis, probably because of prompt, correct diagnosis and a low urological complication rate.

Association between Streptococcus faecalis urinary infections and graft rejection in kidney transplantation

In the first month after transplantation 50% of 193 consecutive renal transplant recipients had bacteriuria. The most common organisms isolated were Streptococcus faecalis (34), Escherichia coli (28), Pseudomonas spp. (11), and staphylococcus (9). There was a significant correlation between infection with Str. faecalis and graft failure at one, three, and twelve months. This observation suggests that urinary infection with Str. faecalis may be associated with graft failure which is probably the result of immunological factors.

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.

Urinary infection in kidney transplantation

Urinary tract infection is the most frequent complication following renal transplantation and is important in the etiology of post-transplantation sepsis. The 87 renal homografts done in 1974 at The New York Hospital-Cornell Medical Center were reviewed retrospectively, with at least one year follow-up, in all cases, with particular attention to factors relating urinary tract infection to ultimate success or failure of the renal graft. The over-all incidence of urinary tract infection was 61%. Early infection was associated with a particularly poor prognosis for graft survival. Most patients with urinary infections after successful transplantation experience a combination of both early and late infections. Anatomic factors constitute a remediable cause of urinary infections after transplantation and should be searched for in cases of multiple, recurrent infections, de novo hypertension, or deterioration of previously stable graft function. There were significant differences in the bacteriologic spectrum of urinary tract infections associated with successful transplants as opposed to unsuccessful transplants.

Effect of ureteral stent on urinary tract infections in renal transplantation

A retrospective study was carried out to determine the effect of ureteral intubation during renal transplantation. We noted urinary tract infections in 76 per cent of those patients whose ureters were intubated during transplantation, as opposed to 45 per cent in those transplant recipients without ureteral stents. The incidence of recurrent urinary tract infections also increased from 18 to 34 per cent with the use of ureteral catheters. Ten separate episodes of bacteremia, indirectly related to indwelling catheters, are noted.