Systematic review: bacterial colonisation of conduits and neobladders-when to test, watch, and treat.

BACKGROUND: Urinary diversion procedures frequently result in bacterial colonisation. There is an increased incidence of developing urinary tract infections (UTIs) in this patient population. Current guidelines, however, recommend against treating this colonisation. This systematic review aimed to determine when and how to test, monitor, and treat bacteriuria in patients with urinary diversion. METHODS: A systematic search strategy was conducted based on keywords "urinary diversion" and "bacteriuria", on MEDLINE, Embase, and Google Scholar. Articles were screened and included only if they reported on (i) testing methods for bacteriuria, (ii) surveillance of bacteriuria over time, or (iii) when and how to treat bacteriuria. Results were summarised and reported using a narrative synthesis. RESULTS: Altogether, 26 studies were included in this review. Inconsistencies were noted in the definitions of bacteriuria, with most studies reporting bacteriuria as > 104 cfu/mL (8/17 studies). Bacteriuria prevalence varied greatly (range 9.1-100%). Monitoring bacteriuria over time may help detect a reduction in bacteriuria, as demonstrated in three studies (follow-up range 5-18 months; sample size 18-56). The link between preceding bacteriuria and subsequent UTIs has not been fully explored yet. Short-term antimicrobial therapy may be useful in the immediate post-operative setting; however, long-term prophylactic treatment is ineffective in preventing bacteriuria. CONCLUSIONS: We recommend consistent reporting of bacteriuria definitions, the benefits of monitoring bacteriuria over time, and use of short-term antimicrobial therapy; bacteriuria should not be treated with long-term therapy.

The local microbiome after pediatric bladder augmentation: intestinal segments and the native urinary bladder host similar mucosal microbiota.

INTRODUCTION: Next-generation sequencing (NGS) techniques have provided novel insights into the microbiome of the urinary bladder (UB). In children after bladder augmentation using either ileum (ileocystoplasty, ICP) or colon (colocystoplasty, CCP), the fate of the mucosal microbiome introduced into the urinary tract remains unknown. OBJECTIVE: The aim was to compare the mucosal microbiome of the native UB vs the augmented intestinal segment (IS) using NGS. STUDY DESIGN: Twelve children after bladder augmentation (ICP n = 6, CCP n = 6) were included. Biopsies were taken during routine postoperative cystoscopy from the native UB and the IS. Specimens underwent whole-genome DNA extraction, 16S rRNA gene amplification, NGS, and Quantitative Insights Into Microbial Ecology (QIIME) data analysis. Downstream statistical data analyses were performed in Calypso. RESULTS: Patients' median age at the time of surgery was 11 years (6-17 years), and the median interval between augmentation and sampling was 7 years (4-13 years). α-Diversity (Shannon diversity index) was not significantly different between IS vs UB, ICP vs CCP, and male vs female. No general differences in the overall bacterial pattern (ß-diversity) were found between IS, UB, ICP, and CCP groups. The groups overlapped in principal coordinate analysis (PCoA) and non-metric multidimensional scaling (NMDS) analysis (Figure). Age at sampling had a statistically significant influence on ß-diversity at the genus level. Corynebacterium, Pseudoxanthomonas, Lactobacillus, Flavobacterium, and Micrococcus were the most dominating taxa detected over all samples. There was an obvious dominance of the genus Corynebacterium in the samples taken from the UB and IS in both ICP and CCP patients. Limitations of this study include the relatively small number of patients. CONCLUSION: After bladder augmentation, the native UB and augmented ISs (ICP and CCP) host similar microbiota despite their distinct differences of originating mucosal anatomy.

[Comparative clinical and morphofunctional evaluation of the intestinal and colonic gastric orthotopic urinary reservoirs at different times of functioning].

The complex clinical and morphological evaluation of different variants of orthopic urinary reservoir (OUR) at different times of functioning was performed. During 1996-2012, orthotopic cystoplasty was performed in 265 patients (ileocystoplasty--in 204, gastrocystoplasty--in 24, and sigmocystoplasty--in 29 patients). There were 207 (77%) men and 61 (23%) women aged 22-75 years (mean age, 57.5 +/- 1,3 years). Cold biopsy over time (1 to 6) was performed in 105 patients. The total number of biopsies was 150. Duration of morphological study was 2-12 years. Clinical examination included assessment of acid-base balance and electrolyte balance of within 3-24 months, evaluation of urodynamic parameters (OUR volume, daytime and nighttime continence, micturition volume), assessment of the frequency and the nature of infection, resistance of microorganisms to antibiotics and the symptoms of inflammatory reaction in period 1-90 months after surgery. Morphological study included histological, histochemical, immunohistochemical, and morphometric methods. Application of a set of clinical, morphological, immunohistochemical examinations is a premise for individual choice of cystoplasty, and creates the preconditions for the correction of the process of adaptation to the OUR, regardless of its form in the early and later stages of its functioning. Due to the good adaptation to the new conditions in all three types of OUR and absence of trends to malignant transformation of its mucosa, the ileocystoplasty is method of choice for creation of OUR, and gastrocystoplasty and sigmocystoplasty are alternatives.

Bacteriuria in patients with an orthotopic ileal neobladder: urinary tract infection or asymptomatic bacteriuria?

OBJECTIVE: To investigate the prevalence of asymptomatic bacteriuria (ABU) and urinary tract infection (UTI), and the local and systemic inflammatory response, in patients with ileal neobladder. PATIENTS AND METHODS: The study included 40 patients who had a radical cystectomy and ileal neobladder. Two urine samples, one for chemical and physical analysis, and cytofluorimetry, and one for urine culture, were collected every 3 months for 9 months after surgery. RESULTS: Of 119 urine cultures, 69 (57%) were positive for bacteria. Only nine of the 40 patients had no bacteriuria on urine culture. Escherichia coli strains were cultured from eight of 10 patients with persistently positive urine. The incidence of bacteriuria was different according to gender. There was a high concentration of leukocytes (0-6 microL) in 118 of 119 samples. The mean concentration of leukocytes in sterile urine culture was 1181/microL, while in patients with ABU the mean was 491 (P < 0.05). CONCLUSION: A positive urine culture is a very common finding in patients with an orthotopic bladder. The most interesting results was the absence of elevated inflammatory indices and/or symptoms, even in those patients with high levels of bacteriuria. Probably this is due to the completely different inflammatory response of ileal mucosa against bacteria than has bladder mucosa. Indeed, the leukocyte concentration detected in urinary sediment was inversely association with bacterial growth in urine cultures. These findings suggest a redefinition of ABU and UTI in patients with an orthotopic neobladder.

Bladder, bowel and bugs--bacteriuria in patients with intestinal urinary diversion.

The incorporation of intestinal segments into the urinary tract favors bacterial growth of the skin flora, anaerobic bacteria, and uropathogenic strains. The route of infection is ascending; bacteria enter the urethra or the abdominal stoma, which is followed by colonization of the reconstructed lower urinary tract. Bacteriuria is common in all kind of reconstructions; however, urine from neobladder patients with complete emptying is reported to carry bacteria to a lesser extent. Clean intermittent catheterization and residual urine seem to increase the bacterial burden. Patients with augmentation cystoplasties constitute a distinct subgroup in which the remaining part of the bladder tissue is an important determinant of urinary tract susceptibility to infection. The increased rate of bacteriuria in the reconstructed patients indicates a lack of "antibacterial defenses", and the symptom free state of the patients suggests that only a restricted host response is triggered. The role of the specific and inflammatory antibacterial defenses in the reconstructed lower urinary tract remains largely unknown.

Microbial flora in ileal and colonic neobladders.

OBJECTIVE: To describe bacterial colonization in patients with ileal and colonic neobladders. METHODS: Twenty-three patients with right colon neobladders, 30 with ileal neobladders, 11 who had undergone radical prostatectomy, and 6 healthy controls were included. Culture of clean-catch, midstream urine specimens was done weekly for 3 weeks, and this was repeated after 6 months. Residual urine was measured, and the patients were interviewed about leakage. All patients and controls were antibiotic free during the study except for 13 of the ileal neobladder patients, who were treated with trimethoprim 100mg daily. RESULTS: Urine cultures from controls and prostatectomy patients were negative for bacteria, whereas 67% of the specimens from patients with neobladders, not on antibiotic therapy, were culture positive, and half of these contained uropathogenic species, such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterococcus faecalis. Bacterial colonization (including uropathogenic strains) was strongly correlated with residual urine (p<0.005), but not with leakage. Anaerobic strains were found more frequently (p=0.04) in urine from ileal neobladders than in urine from colonic neobladders. The 13 patients with ileal neobladders and on prophylactic antibiotic therapy carried bacteriuria in 80% of the samples, the majority being anaerobic strains. Uropathogenic strains, mainly Enterecoccus faecalis was revealed in 30% of the samples. CONCLUSIONS: The lower urinary tract of patients with ileal or colonic neobladders is heavily colonized with potentially uropathogenic and anaerobic bacteria. Complete bladder emptying reduces the bacterial burden. Anaerobic colonization is increased in neobladders reconstructed from ileum. Prophylactic antibiotic therapy does not seem to reduce the bacterial burden, but interferes with the bacterial composition.

Incidence and significance of positive urine cultures in patients with an orthotopic neobladder.

PURPOSE: With an intact normal bladder bacterial colonization is uncommon unless intermittent catheterization is instituted. Because intestine, which is normally colonized with bacteria, is used to form an orthotopic neobladder, we determined whether patients with orthotopic urinary diversion are at increased risk for urinary tract infection and urosepsis. MATERIALS AND METHODS: A total of 66 patients who received an orthotopic neobladder after radical cystectomy were prospectively evaluated with urinalysis and culture 2 months to 4 years postoperatively. No patient was on suppressive antibiotics unless they had recurrent urinary tract infections. RESULTS: A total of 55 voided normally and 11 performed intermittent catheterization at least once daily due to high post-void residual urine. Of the patients who voided normally 78% had at least 1 positive urinalysis. If a patient had a positive urinalysis, bacteria was identified on culture in 50%. Overall 26 (39%) and 8 (12%) patients had a urinary tract infection and urosepsis, respectively. The estimated 5-year probability of urinary tract infection and urosepsis for patients who voided independently were 58% and 18%, respectively. Urine culture with greater than 100,000 cfu bacteria and female gender were the only factors predictive of urinary tract infection on multivariate analysis. Recurrent urinary tract infection was the only predictor for urosepsis. Intermittent catheterization or hydronephrosis was not related to urinary tract infection or urosepsis. CONCLUSIONS: The presence of small bowel intestine appears to promote asymptomatic bacterial colonization but urosepsis rarely occurs unless the patient has recurrent urinary tract infections. Prophylactic antibiotics are recommended only for patients with recurring urinary tract infections but treating a positive urinary culture in the absence of specific voiding symptoms is not advocated in this patient population.

Characterization of Escherichia coli strains causing urinary tract infections in patients with transposed intestinal segments.

PURPOSE: Transposition of intestinal segments into the urinary tract predisposes to urinary tract infections. We characterized bacterial infections in these patients and examined the virulence genotype and persistence of Escherichia coli isolates. MATERIALS AND METHODS: We followed 26 patients who underwent bladder reconstructive surgery using transposed intestinal segments. E. coli strains isolated from the urine of these patients were genotyped for established virulence determinants and the frequency of carriage was compared with E. coli strains isolated from community acquired urinary infections and the fecal flora of anonymous volunteers. A longitudinal study of E. coli strains in 9 patients was also done using pulsed field gel electrophoresis. RESULTS: E. coli was the most frequently isolated organism, responsible for 59% (62 of 105) of monobacterial infections. Other bacteria isolated included Klebsiella species, Proteus species and Enterococcus faecalis. Community acquired E. coli strains were more likely to carry multiple determinants for particular adhesins (P and S fimbriae) and toxins (alpha-hemolysin and cytotoxic necrotizing factor) than fecal strains. Carriage frequency for bladder reconstruction strains was intermediary and not significantly different. The key finding was that E. coli strains persisted for prolonged periods, including 2 years in certain patients, often despite various antimicrobial treatments. CONCLUSIONS: This study highlights that further steps must be taken to prevent and treat urinary tract infections in this susceptible group. Particular attention should be given to the treatment of persistent infections.

Electrified urinary drainage bag: an in vitro study.

An experimental study was designed to examine the effect of electrical current on bacteria-contaminating urinary drainage bags. An experimental model analogous to a urinary drainage system has been formed. Bottles containing 1,000 ml urine inoculated with Pseudomonas aeruginosa, Klebsiella pneumoniae or Escherichia coli in different experimental settings were drained with constant speed into urinary drainage bags in which platinum electrodes had been implanted. An experimental procedure involved applying an electrical current with a 12 V DC generator into bags containing urine for 24 h. Cultures were obtained separately from the bags and microorganism-inoculated bottles for 24 h and following a cessation of electrical current for another 24 h. In electrified bags, P. aeruginosa was killed in all experiments. E. coli and K. pneumoniae were eradicated at the end of 24 h. However, K. pneumoniae began to grow in increasing numbers following the cessation of the electrical current. An electrical current might decrease or eradicate the bacteria in urinary-drainage bags. This might be one of the ways to decrease the risk of in vivo cross-contamination and nosocomial infections.

Fatal pseudomembranous colitis in a continent urinary neobladder.

Antibiotic-associated colitis is a significant clinical problem, especially in patients hospitalized for longer than three days. Clostridium difficile is now established as the most common nosocomial enteric pathogen causing antibiotic-associated colitis. The condition rarely occurs beyond the boundaries of the large bowel, but can represent significant diagnostic and therapeutic problems if it involves bowel that is used in the creation of a diversionary reservoir such as an ileo-cecal neobladder. We present what we believe to be the first reported case of fatal pseudomembranous colitis occurring in an ileo-cecal neobladder.