Fimbriae reprogram host gene expression - Divergent effects of P and type 1 fimbriae.

Pathogens rely on a complex virulence gene repertoire to successfully attack their hosts. We were therefore surprised to find that a single fimbrial gene reconstitution can return the virulence-attenuated commensal strain Escherichia coli 83972 to virulence, defined by a disease phenotype in human hosts. E. coli 83972pap stably reprogrammed host gene expression, by activating an acute pyelonephritis-associated, IRF7-dependent gene network. The PapG protein was internalized by human kidney cells and served as a transcriptional agonist of IRF-7, IFN-ß and MYC, suggesting direct involvement of the fimbrial adhesin in this process. IRF-7 was further identified as a potent upstream regulator (-log (p-value) = 61), consistent with the effects in inoculated patients. In contrast, E. coli 83972fim transiently attenuated overall gene expression in human hosts, enhancing the effects of E. coli 83972. The inhibition of RNA processing and ribosomal assembly indicated a homeostatic rather than a pathogenic end-point. In parallel, the expression of specific ion channels and neuropeptide gene networks was transiently enhanced, in a FimH-dependent manner. The studies were performed to establish protective asymptomatic bacteriuria in human hosts and the reconstituted E. coli 83972 variants were developed to improve bacterial fitness for the human urinary tract. Unexpectedly, P fimbriae were able to drive a disease response, suggesting that like oncogene addiction in cancer, pathogens may be addicted to single super-virulence factors.

Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America.

Asymptomatic bacteriuria (ASB) is a common finding in many populations, including healthy women and persons with underlying urologic abnormalities. The 2005 guideline from the Infectious Diseases Society of America recommended that ASB should be screened for and treated only in pregnant women or in an individual prior to undergoing invasive urologic procedures. Treatment was not recommended for healthy women; older women or men; or persons with diabetes, indwelling catheters, or spinal cord injury. The guideline did not address children and some adult populations, including patients with neutropenia, solid organ transplants, and nonurologic surgery. In the years since the publication of the guideline, further information relevant to ASB has become available. In addition, antimicrobial treatment of ASB has been recognized as an important contributor to inappropriate antimicrobial use, which promotes emergence of antimicrobial resistance. The current guideline updates the recommendations of the 2005 guideline, includes new recommendations for populations not previously addressed, and, where relevant, addresses the interpretation of nonlocalizing clinical symptoms in populations with a high prevalence of ASB.

Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America.

Asymptomatic bacteriuria (ASB) is a common finding in many populations, including healthy women and persons with underlying urologic abnormalities. The 2005 guideline from the Infectious Diseases Society of America recommended that ASB should be screened for and treated only in pregnant women or in an individual prior to undergoing invasive urologic procedures. Treatment was not recommended for healthy women; older women or men; or persons with diabetes, indwelling catheters, or spinal cord injury. The guideline did not address children and some adult populations, including patients with neutropenia, solid organ transplants, and nonurologic surgery. In the years since the publication of the guideline, further information relevant to ASB has become available. In addition, antimicrobial treatment of ASB has been recognized as an important contributor to inappropriate antimicrobial use, which promotes emergence of antimicrobial resistance. The current guideline updates the recommendations of the 2005 guideline, includes new recommendations for populations not previously addressed, and, where relevant, addresses the interpretation of nonlocalizing clinical symptoms in populations with a high prevalence of ASB.

Molecular Basis of Acute Cystitis Reveals Susceptibility Genes and Immunotherapeutic Targets.

Tissue damage is usually regarded as a necessary price to pay for successful elimination of pathogens by the innate immune defense. Yet, it is possible to distinguish protective from destructive effects of innate immune activation and selectively attenuate molecular nodes that create pathology. Here, we identify acute cystitis as an Interleukin-1 beta (IL-1ß)-driven, hyper-inflammatory condition of the infected urinary bladder and IL-1 receptor blockade as a novel therapeutic strategy. Disease severity was controlled by the mechanism of IL-1ß processing and mice with intact inflammasome function developed a moderate, self-limiting form of cystitis. The most severe form of acute cystitis was detected in mice lacking the inflammasome constituents ASC or NLRP-3. IL-1ß processing was hyperactive in these mice, due to a new, non-canonical mechanism involving the matrix metalloproteinase 7- (MMP-7). ASC and NLRP-3 served as transcriptional repressors of MMP7 and as a result, Mmp7 was markedly overexpressed in the bladder epithelium of Asc-/- and Nlrp3-/- mice. The resulting IL-1ß hyper-activation loop included a large number of IL-1ß-dependent pro-inflammatory genes and the IL-1 receptor antagonist Anakinra inhibited their expression and rescued susceptible Asc-/- mice from bladder pathology. An MMP inhibitor had a similar therapeutic effect. Finally, elevated levels of IL-1ß and MMP-7 were detected in patients with acute cystitis, suggesting a potential role as biomarkers and immunotherapeutic targets. The results reproduce important aspects of human acute cystitis in the murine model and provide a comprehensive molecular framework for the pathogenesis and immunotherapy of acute cystitis, one of the most common infections in man. TRIAL REGISTRATION: The clinical studies were approved by the Human Ethics Committee at Lund University (approval numbers LU106-02, LU236-99 and Clinical Trial Registration RTP-A2003, International Committee of Medical Journal Editors, www.clinicaltrials.gov).

Triggered Urine Interleukin-6 Correlates to Severity of Symptoms in Nonfebrile Lower Urinary Tract Infections.

PURPOSE: Objective diagnosis of symptomatic urinary tract infections in patients prone to asymptomatic bacteriuria is compromised by local host responses that are already present and the positive urine culture. We investigated interleukin-6 as a biomarker for nonfebrile urinary tract infection severity and diagnostic thresholds for interleukin-6 and 8, and neutrophils to differentiate between asymptomatic bacteriuria and urinary tract infection. MATERIALS AND METHODS: Patients with residual urine and neurogenic bladders due to spinal lesions included in a long-term Escherichia coli 83972 asymptomatic bacteriuria inoculation trial were monitored for 2 years. Symptom scoring and urine sampling to estimate interleukin-6 and 8, and neutrophils were performed regularly monthly and at urinary tract infection episodes. RESULTS: Patients were followed in the complete study for a mean of 19 months (range 10 to 27) and those with asymptomatic bacteriuria with E. coli 83972 were followed a mean of 11 months (range 4 to 19). A total of 37 nonfebrile urinary tract infection episodes with complete data on interleukin-6 and 8, neutrophils and symptom scoring were documented. Interleukin-6 was the only marker that persistently increased during urinary tract infection compared to asymptomatic bacteriuria in pooled and paired intra-individual comparisons (p <0.05). Interleukin-6 above the threshold (greater than 25 ng/l) correlated to more severe urinary tract infection symptoms (p <0.05). The sensitivity and specificity of all biomarkers were poor/moderate when differentiating asymptomatic bacteriuria vs all urinary tract infection episodes. However, in urinary tract infections with worse symptoms interleukin-6 and neutrophils demonstrated equal good/excellent outcomes. CONCLUSIONS: Triggered interleukin-6 correlated to urinary tract infection symptom severity and demonstrated a promising differential diagnostic capacity to discriminate urinary tract infection from asymptomatic bacteriuria. Future studies should explore interleukin-6 as a biomarker of urinary tract infection severity and assess the treatment indication in nonfebrile urinary tract infections.

Antimicrobial resistance in urosepsis: outcomes from the multinational, multicenter global prevalence of infections in urology (GPIU) study 2003-2013.

OBJECTIVE: Primary objective was to identify the (1) relationship of clinical severity of urosepsis with the pathogen spectrum and resistance and (2) appropriateness of using the pathogen spectrum and resistance rates of health-care-associated urinary tract infections (HAUTI) as representative of urosepsis. The secondary objective was to provide an overview of the pathogens and their resistance profile in patients with urosepsis. POPULATION AND METHODS: A point prevalence study carried out in 70 countries (2003-2013). Population studied included; 408 individuals with microbiologically proven urosepsis, 1606 individuals with microbiological proof of HAUTI and 27,542 individuals hospitalised in urology wards. Main outcomes are pathogens and resistance identified in HAUTIs and urosepsis including its clinical severity. A statistical model that included demographic factors (study year, geographical location, hospital setting) was used for analysis. RESULTS: Amongst urology practices, the prevalence of microbiologically proven HAUTI and urosepsis was 5.8 and 1.5 %, respectively. Frequent pathogens in urosepsis were E. coli (43 %), Enterococcus spp. (11 %), P. aeruginosa (10 %) and Klebsiella spp. (10 %). Resistance to commonly prescribed antibiotics was high and rates ranged from 8 % (imipenem) to 62 % (aminopenicillin/ß lactamase inhibitors); 45 % of Enterobacteriaceae and 21 % of P. aeruginosa were multidrug-resistant. Resistance rates in urosepsis were higher than in other clinical diagnosis of HAUTI (Likelihood ratio <0.05). CONCLUSIONS: It is not appropriate to use the pathogen spectrum and resistance rates of other HAUTIs as representative of urosepsis to decide on empirical treatment of urosepsis. Resistance rates in urosepsis are high, and precautions should be made to avoid further increase.

Predictive value of urinary interleukin-6 for symptomatic urinary tract infections in a nursing home population.

OBJECTIVES: To study urinary interleukin-6, interleukin-8 and pyuria during episodes of asymptomatic bacteriuria and symptomatic urinary tract infection in the institutionalized elderly, and to investigate the role of interleukin-6 as a biomarker for differential diagnosis. METHODS: Levels of interleukin-6, interleukin-8 and pyuria were assessed in 35 older adults with asymptomatic bacteriuria and symptomatic urinary tract infection to define possible diagnostic thresholds. In a two-phase intervention study, the antibiotic treatment for urinary tract infection before and after introduction of urinary interleukin-6 as a biomarker was then assessed. RESULTS: Asymptomatic bacteriuria patients had no or low levels of interleukin-6, and low levels of interleukin-8 and pyuria. Women had lower interleukin-6 and interleukin-8 than men (P = 0.05). Interleukin-6 was the only marker showing significant increases during urinary tract infection episodes in patients with both asymptomatic bacteriuria and urinary tract infection, in pooled (P = 0.042) and in paired intra-individual (P = 0.017) comparisons. In the intervention study lectures, the increased use of urine cultures and the introduction of interleukin-6 as a biomarker reduced antibiotic treatments by 20%. Antibiotic-treated urinary tract infection episodes had increased interleukin-6 as compared with urinary tract infection episodes not treated (P = 0.02), and as compared with asymptomatic bacteriuria patients (P < 0.0001). The sensitivity and specificity of interleukin-6 (cut-off 25 pg/mL) differentiating asymptomatic bacteriuria from urinary tract infection was 57% and 80%, respectively. CONCLUSIONS: Urinary interleukin-6 shows promise as a biomarker to detect the transition from asymptomatic bacteriuria to symptomatic urinary tract infection in older adults. Further larger studies with robust methodology are warranted to determine whether development for near to patient testing would be worthwhile.

Rare emergence of symptoms during long-term asymptomatic Escherichia coli 83972 carriage without an altered virulence factor repertoire.

PURPOSE: Asymptomatic bacteriuria established by intravesical inoculation of Escherichia coli 83972 is protective in patients with recurrent urinary tract infections. In this randomized, controlled crossover study a total of 3 symptomatic urinary tract infection episodes developed in 2 patients while they carried E. coli 83972. We examined whether virulence reacquisition by symptom isolates may account for the switch from asymptomatic bacteriuria to symptomatic urinary tract infection. MATERIALS AND METHODS: We used E. coli 83972 re-isolates from 2 patients in a prospective study and from another 2 in whom symptoms developed after study completion. We phylogenetically classified the re-isolates, and identified the genomic restriction patterns and gene expression profiles as well as virulence gene structure and phenotypes. In vivo virulence was examined in the murine urinary tract infection model. RESULTS: The fim, pap, foc, hlyA, fyuA, iuc, iroN, kpsMT K5 and malX genotypes of the symptomatic re-isolates remained unchanged. Bacterial gene expression profiles of flagellated symptomatic re-isolates were unique to each host, providing no evidence of common deregulation. Symptomatic isolates did not differ in virulence from the wild-type strain, as defined in the murine urinary tract infection model by persistence, symptoms or innate immune activation. CONCLUSIONS: The switch from asymptomatic E. coli 83972 carriage to symptomatic urinary tract infection was not explained by reversion to a functional virulence gene repertoire.

Host imprints on bacterial genomes--rapid, divergent evolution in individual patients.

Bacteria lose or gain genetic material and through selection, new variants become fixed in the population. Here we provide the first, genome-wide example of a single bacterial strain's evolution in different deliberately colonized patients and the surprising insight that hosts appear to personalize their microflora. By first obtaining the complete genome sequence of the prototype asymptomatic bacteriuria strain E. coli 83972 and then resequencing its descendants after therapeutic bladder colonization of different patients, we identified 34 mutations, which affected metabolic and virulence-related genes. Further transcriptome and proteome analysis proved that these genome changes altered bacterial gene expression resulting in unique adaptation patterns in each patient. Our results provide evidence that, in addition to stochastic events, adaptive bacterial evolution is driven by individual host environments. Ongoing loss of gene function supports the hypothesis that evolution towards commensalism rather than virulence is favored during asymptomatic bladder colonization.

Update on biofilm infections in the urinary tract.

PURPOSE: Biofilm infections have a major role in implants or devices placed in the human body. As part of the endourological development, a great variety of foreign bodies have been designed, and with the increasing number of biomaterial devices used in urology, biofilm formation and device infection is an issue of growing importance. METHODS: A literature search was performed in the Medline database regarding biofilm formation and the role of biofilms in urogenital infections using the following items in different combinations: "biofilm," "urinary tract infection," "bacteriuria," "catheter," "stent," and "encrustation." The studies were graded using the Oxford Centre for Evidence-based Medicine classification. RESULTS: The authors present an update on the mechanism of biofilm formation in the urinary tract with special emphasis on the role of biofilms in lower and upper urinary tract infections, as well as on biofilm formation on foreign bodies, such as catheters, ureteral stents, stones, implants, and artificial urinary sphincters. The authors also summarize the different methods developed to prevent biofilm formation on urinary foreign bodies. CONCLUSIONS: Several different approaches are being investigated for preventing biofilm formation, and some promising results have been obtained. However, an ideal method has not been developed. Future researches have to aim at identifying effective mechanisms for controlling biofilm formation and to develop antimicrobial agents effective against bacteria in biofilms.

Immunomodulation therapy offers new molecular strategies to treat UTI.

Innovative solutions are needed for the treatment of bacterial infections, and a range of antibacterial molecules have been explored as alternatives to antibiotics. A different approach is to investigate the immune system of the host for new ways of making the antibacterial defence more efficient. However, the immune system has a dual role as protector and cause of disease: in addition to being protective, increasing evidence shows that innate immune responses can become excessive and cause acute symptoms and tissue pathology during infection. This role of innate immunity in disease suggests that the immune system should be targeted therapeutically, to inhibit over-reactivity. The ultimate goal is to develop therapies that selectively attenuate destructive immune response cascades, while augmenting the protective antimicrobial defence but such treatment options have remained underexplored, owing to the molecular proximity of the protective and destructive effects of the immune response. The concept of innate immunomodulation therapy has been developed successfully in urinary tract infections, based on detailed studies of innate immune activation and disease pathogenesis. Effective, disease-specific, immunomodulatory strategies have been developed by targeting specific immune response regulators including key transcription factors. In acute pyelonephritis, targeting interferon regulatory factor 7 using small interfering RNA or treatment with antimicrobial peptide cathelicidin was protective and, in acute cystitis, targeting overactive effector molecules such as IL-1ß, MMP7, COX2, cAMP and the pain-sensing receptor NK1R has been successful in vivo. Furthermore, other UTI treatment strategies, such as inhibiting bacterial adhesion and vaccination, have also shown promise.

International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: A 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases.

A Panel of International Experts was convened by the Infectious Diseases Society of America (IDSA) in collaboration with the European Society for Microbiology and Infectious Diseases (ESCMID) to update the 1999 Uncomplicated Urinary Tract Infection Guidelines by the IDSA. Co-sponsoring organizations include the American Congress of Obstetricians and Gynecologists, American Urological Association, Association of Medical Microbiology and Infectious Diseases-Canada, and the Society for Academic Emergency Medicine. The focus of this work is treatment of women with acute uncomplicated cystitis and pyelonephritis, diagnoses limited in these guidelines to premenopausal, non-pregnant women with no known urological abnormalities or co-morbidities. The issues of in vitro resistance prevalence and the ecological adverse effects of antimicrobial therapy (collateral damage) were considered as important factors in making optimal treatment choices and thus are reflected in the rankings of recommendations.

Immunomodulation-A Molecular Solution to Treating Patients with Severe Bladder Pain Syndrome?

BACKGROUND: Patients with bladder pain syndrome experience debilitating pain and extreme frequency of urination. Numerous therapeutic approaches have been tested, but as the molecular basis of disease has remained unclear, specific therapies are not available. OBJECTIVE: Recently, a systematic gene deletion strategy identified interleukin-1 (IL-1) hyperactivation as a cause of severe cystitis in a murine model. Treatment with an IL-1 receptor antagonist (IL-1RA) restored health in genetically susceptible mice, linking IL-1-dependent inflammation to pain and pathology in the bladder mucosa. The study objective was to investigate whether IL-1RA treatment might be beneficial in patients with bladder pain syndrome. DESIGN SETTING AND PARTICIPANTS: Patients diagnosed with bladder pain syndrome were invited to participate and subjected to daily IL-1RA injections for 1 wk, followed by a treatment break. Patients with other urological disorders accompanied by pain were included as controls. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: When symptoms returned, treatment was resumed and responding patients were maintained on treatment long term, with individualized dosing regimens. Symptom scores were recorded and molecular effects were quantified by neuropeptide and gene expression analysis. DNA samples were subjected to exome genotyping. RESULTS AND LIMITATIONS: IL-1RA treatment reduced bladder pain and the frequency of urination in 13/17 patients (p < 0.001). Substance P levels in urine were lowered, and responders returned to a more normal lifestyle. Neuroinflammatory-dependent and IL-1-dependent gene networks were inhibited, as well as regulators of innate immunity. Genotyping revealed disease-associated IL1R1, NLRP3, and IL1RN DNA sequence variants in the responders. Controls did not benefit from IL-1RA treatment, except for one patent with cystitis cystica. CONCLUSIONS: In this clinical study, IL-1RA treatment is proposed to reduce chronic bladder pain, immediately and in the long term. Despite the limited number of study patients, the potent acute effect and lasting symptom relief indicate that this therapeutic approach may be worth exploring in controlled clinical trials. PATIENT SUMMARY: Treatment with an interleukin-1 (IL-1) receptor antagonist is proposed for treating bladder pain syndrome, as it can result in symptom relief and increase quality of life. Reduced neuroinflammation and IL-1 signaling provided molecular evidence of the treatment effects.

Active bacterial modification of the host environment through RNA polymerase II inhibition.

Unlike pathogens, which attack the host, commensal bacteria create a state of friendly coexistence. Here, we identified a mechanism of bacterial adaptation to the host niche, where they reside. Asymptomatic carrier strains were shown to inhibit RNA polymerase II (Pol II) in host cells by targeting Ser2 phosphorylation, a step required for productive mRNA elongation. Assisted by a rare, spontaneous loss-of-function mutant from a human carrier, the bacterial NlpD protein was identified as a Pol II inhibitor. After internalization by host cells, NlpD was shown to target constituents of the Pol II phosphorylation complex (RPB1 and PAF1C), attenuating host gene expression. Therapeutic efficacy of a recombinant NlpD protein was demonstrated in a urinary tract infection model, by reduced tissue pathology, accelerated bacterial clearance, and attenuated Pol II-dependent gene expression. The findings suggest an intriguing, evolutionarily conserved mechanism for bacterial modulation of host gene expression, with a remarkable therapeutic potential.

Escherichia coli 83972 bacteriuria protects against recurrent lower urinary tract infections in patients with incomplete bladder emptying.

PURPOSE: We determined if the deliberate establishment of asymptomatic bacteriuria with Escherichia coli 83972 in patients with incomplete bladder emptying and recurrent urinary tract infection protects against recurrence. MATERIALS AND METHODS: In phase 1 of the study the patients were randomized to blinded inoculations with E. coli 83972 or saline. Crossover occurred after monitoring for 12 months or after a urinary tract infection. The outcome was the time to the first urinary tract infection in patients with and without E. coli 83972 bacteriuria. In phase 2 patients were subjected to additional blinded inoculations to extend periods with and without E. coli 83972 bacteriuria. The outcome was the number of urinary tract infections during 12 months with and 12 months without E. coli 83972 bacteriuria. RESULTS: A total of 20 patients completed the study. In phase 1 the time to the first urinary tract infection was longer with than without E. coli 83972 bacteriuria (median 11.3 vs 5.7 months, sign test p = 0.0129). Phase 2 was analyzed after patients had spent a total of 202 months with and 168 months without E. coli 83972 bacteriuria. There were fewer reported urinary tract infection episodes with vs without E. coli 83972 bacteriuria (13 vs 35 episodes, paired t test p = 0.009, CI 0.31-1.89). There was no febrile urinary tract infection episode in either of the study arms and no significant side effects of intravesical bacterial inoculation were reported. CONCLUSIONS: Deliberately induced E. coli 83972 bacteriuria protected patients with incomplete bladder emptying who are prone to urinary tract infection from recurrent urinary tract infection as demonstrated by the delay in time to urinary tract infection and the decrease in number of urinary tract infection episodes.

Open partial nephrectomy for renal cell cancer in a medium patient volume centre: is high quality possible?

OBJECTIVE: To describe the surgical complication rate of open partial nephrectomy (OPN) in patients with renal tumours, and to report the oncological long-term outcome in unilateral renal cell cancer patients subjected to this procedure, from a medium patient volume urological centre. MATERIAL AND METHODS: Data from all patients (n = 89) subjected to OPN for proven or suspected renal cell cancer during the period 1965-2007 were registered in a specifically designed database system. Tumour stage and size, surgical margin, histology, perioperative and postoperative complications were analysed in all patients. In addition, long-term follow-up outcomes in malignant unilateral tumours (n = 51) were analysed. RESULTS: Seventy-four of the resected tumours were malignant. Six of these had a positive surgical margin; five from patients with multifocal or bilateral tumours and one from a patient with a solitary malignant cyst. Perioperative complications were registered in only one case (1%). Postoperative complications (within 30 days postoperatively) reached 18%. The long-term follow-up (mean 79 months, median 49 months, range 14 months to 26 years) in patients with unilateral malignant tumours, all staged T1-T2, revealed two systemic recurrences, both in patients with poor prognostic markers at the time of surgery, but no local recurrence. CONCLUSIONS: OPN has complication rates similar to open radical nephrectomy. Long-term tumour control in unilateral cases and with organ confined disease is excellent. The results demonstrate that carefully performed OPN at a medium-volume centre can achieve equal results to high-volume centres.

Biomarkers in urinary tract infections - which ones are suitable for diagnostics and follow-up?

Introduction: Urinary tract infections (UTIs) are one of the most common infections worldwide. Under special circumstances, clinicians must rely on laboratory findings, which might have a weak predicting value, misguiding the practitioners and leading to incorrect diagnosis and overuse of antibiotics. Therefore, there is an urgent need for reliable biomarkers in UTIs. Methods: We performed a literature search for biomarkers used in UTIs from January 1999 until May 2020. We used "urinary tract infection" and "biomarker" as the main key words in the PubMed, Medline and Cochrane databases. After peer review, we excluded the duplicates and identified the suitable articles, from which we collected the data and divided the available biomarkers into 5 groups: i) conventional markers; ii) promising, thoroughly studied biomarkers; iii) promising biomarkers that need further studies; iv) biomarkers of unknown significance; v) controversial, not useful markers. Results: We found 131 articles, mostly from the paediatric population. Neutrophil gelatinase-associated lipocalin (NGAL) and interleukins (IL) have a leading role in diagnosing and differentiating UTIs based on a lot of observational, comparative trials. Heparin Binding Protein (HBP), Lactoferrin (LF), Heat-Shock Protein-70 (HSP-70), Human Defensin-5 (HD-5), Lipopolysaccharide Binding Protein (LBP) and mass spectrometry studies are promising, but confirming data are lacking. The measurable components of the innate immune system and local host cell response could be appropriate biomarkers, but their significance is currently unknown. Conclusions: Conventional biomarkers for UTIs have low specificity. The use of urinary NGAL and interleukins could improve the sensitivity and specificity of laboratory diagnosis of UTIs.

Asymptomatic Bacteriuria is Harmless and Even Protective: Don't Treat if You Don't Have a Very Specific Reason.

Symptom-free bacterial colonization of the lower urinary tract in an otherwise healthy individual was long misunderstood. Our current understanding is based on solid research proving that asymptomatic bacteriuria (ABU) is harmless and even protective against symptomatic urinary tract infection episodes. Thus, ABU should not be treated in patients with the exception of before endosurgery and, until we have accumulated more knowledge, in pregnant women.

Transurethral Resection of the Prostate: are We Following the Guidelines? - Outcomes from the Global Prevalence of Infections in Urology (GPIU) Study.

Transurethral resection of the prostate (TURP) is one of the most common urological procedures. With the increasing rate of multiresistant infections including urosepsis, it is essential for all surgeons to adhere to the relevant international guidelines to prevent infectious complications. The aim of this prospective, multinational, multicentre study was to evaluate compliance with recommended infection control measures regarding TURP procedures. The study was performed as a side questionnaire to the annual Global Prevalence Study of Infections in Urology (GPIU) between 2006 and 2009. Patients that had undergone TURP were eligible. Baseline data about hospitals and patients were collected. The questionnaire contained questions regarding preoperative microbiological investigations, catheter care and performance of perioperative antibiotic prophylaxis. A total of 825 men were included from 138 participating centres from Africa, Asia, Europe and South America. Only 50.1% of the patients received perioperative antibiotic prophylaxis with a median duration of 3 days (interquartile range [IQR] = 1-7 days). Preoperative urine culture was taken in 59.2%. The catheter was replaced in 1 week prior to the surgery only in 38.3% of cases. Compliance with the recommended infection control measures regarding TURP were only moderate, despite high grade recommendations in relevant international Guidelines. Stronger guideline adherence is necessary to improve patient care decrease antibiotic consumption in line with antibiotic stewardship in surgical practices.

Molecular basis of commensalism in the urinary tract: low virulence or virulence attenuation?

In some patients, Escherichia coli strains establish significant bacteriuria without causing symptoms of urinary tract infection (UTI). These asymptomatic-bacteriuria (ABU) strains have been shown to express fewer virulence factors than the uropathogenic E. coli (UPEC) strains that cause severe, symptomatic UTI. Paradoxically, ABU strains carry many typical UPEC virulence genes, and the molecular basis of their low virulence therefore remains unclear. This study examined whether ABU strains might evolve from UPEC by genome loss and virulence gene attenuation. The presence of conserved E. coli K-12 genes was examined using an E. coli K-12 strain MG1655-specific DNA array and the distribution of UPEC virulence-related genes was examined with the E. coli pathoarray. Two groups of strains could be distinguished. Several ABU strains were shown by multilocus sequence typing and by comparative genomic analyses to be related to UPEC but to have smaller genome sizes. There were significant alterations in essential virulence genes, including reductive evolution by point mutations, DNA rearrangements, and deletions. Other strains were unrelated to UPEC and lacked most of the virulence-associated genes. The results suggest that some ABU strains arise from virulent strains by attenuation of virulence genes while others are nonvirulent and resemble commensal strains. We propose that virulence attenuation might constitute a general mechanism for mucosal pathogens to evolve toward commensalism.