Urinary catheter-associated microbiota change in accordance with treatment and infection status

Engineered microorganisms: A new direction in kidney stone prevention and treatment

Numerous studies have shown that intestinal and urinary tract flora are closely related to the formation of kidney stones. The removal of probiotics represented by lactic acid bacteria and the colonization of pathogenic bacteria can directly or indirectly promote the occurrence of kidney stones. However, currently existing natural probiotics have limitations. Synthetic biology is an emerging discipline in which cells or living organisms are genetically designed and modified to have biological functions that meet human needs, or even create new biological systems, and has now become a research hotspot in various fields. Using synthetic biology approaches of microbial engineering and biological redesign to enable probiotic bacteria to acquire new phenotypes or heterologous protein expression capabilities is an important part of synthetic biology research. Synthetic biology modification of microorganisms in the gut and urinary tract can effectively inhibit the development of kidney stones by a range of means, including direct degradation of metabolites that promote stone production or indirect regulation of flora homeostasis. This article reviews the research status of engineered microorganisms in the prevention and treatment of kidney stones, to provide a new and effective idea for the prevention and treatment of kidney stones.

Urinary Microbiome in Bladder Diseases-Review

The microbiome is the totality of microorganisms found in a specific biological niche. It has been proven that in the human body, the microbiome is responsible for its proper functioning. Dysbiosis, i.e., a disturbance in the composition of the microbiome, may be associated with the pathogenesis of many human diseases. Until recently, studies did not focus on the microbiome of the urinary tract, because, since the 19th century, there had been a dogma that urine in healthy people is sterile. Yet, advances in molecular biology techniques have allowed this dogma to be overthrown. The use of DNA sequencing has shown that the urinary tract has its own endogenous microbiome. This discovery enabled further research on the characteristics of the urine microbiomes of healthy people, as well as on the role of the urine microbiome in the pathogenesis of many urological diseases, including bladder diseases. The aim of this review is to summarize the current knowledge on the urinary microbiome in bladder diseases and to identify potential directions for further research.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Intravesical Lactobacillus rhamnosus GG Alters Urobiome Composition and Diversity Among People With Neurogenic Lower Urinary Tract Dysfunction

Background

Neurogenic bladder is associated with bacterial colonization and frequent urinary tract infections.

Objectives

To explore the effects of one to two doses of intravesical Lactobacillus rhamnosus GG (LGG) on the urobiomes of adults with spinal cord injury/disease (SCI/D) who manage their bladders with intermittent catheterization (IC).

Methods

This was a pilot substudy within an 18-month phase 1 clinical trial of self-instilled intravesical LGG for urinary symptoms as directed by the Self-Management Protocol using Probiotics (SMP-Pro). Urine samples were collected monthly when participants were asymptomatic. When SMP-Pro "trigger" symptoms (cloudier and/or more foul-smelling urine) occurred, urine samples were collected immediately pre-LGG instillation and 24 to 48 hours after LGG instillation. Urine was collected via a new catheter, immediately placed on ice/freezer, and processed within 12 hours. Genomic DNA was isolated, and the V4 region of the 16S rRNA bacterial gene was amplified and high throughput sequenced. Amplicon sequence variants were inferred and bacterial composition, community structure, and variation across clinical phenotypes were determined.

Results

126 urine samples were collected from 26 participants (SCI/D = 23; multiple sclerosis = 2; spina bifida = 1) between 20 and 57 years of age. The urobiomes were characterized by four dominant phyla (>1%): Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria, which were comprised of six dominant genera (>3%): Escherichia/Shigella (29.1%), Klebsiella (22.4%), Proteus (15.2%), Aerococcus (6.3%), Streptococcus (6.0%), and Pluralibacter (3.0%). Post-LGG samples were associated with a decline in Escherichia/Shigella predominance (p < .001) and altered bacterial diversity (p < .05).

Conclusion

Among people with SCI/D who use IC, intravesical LGG alters the bacterial composition and diversity of the urine ecosystem, potentially disrupting the uropathogenic urobiome.

Profiling the Urobiota in a Pediatric Population with Neurogenic Bladder Secondary to Spinal Dysraphism

The human bladder has been long thought to be sterile until that, only in the last decade, advances in molecular biology have shown that the human urinary tract is populated with microorganisms. The relationship between the urobiota and the development of urinary tract disorders is now of great interest. Patients with spina bifida (SB) can be born with (or develop over time) neurological deficits due to damaged nerves that originate in the lower part of the spinal cord, including the neurogenic bladder. This condition represents a predisposing factor for urinary tract infections so that the most frequently used approach to treat patients with neurogenic bladder is based on clean intermittent catheterization (CIC). In this study, we analyzed the urobiota composition in a pediatric cohort of patients with SB compared to healthy controls, as well as the urobiota characteristics based on whether patients received CIC or not.

Menopausal Changes in the Microbiome-A Review Focused on the Genitourinary Microbiome

A balanced interaction between the host and its microbiome is crucial to health. Research regarding the significance of the gut and vaginal microbiomes in female health is substantial. However, less data regarding the urinary microbiome are available. Interactions between the gut, vaginal, and urinary microbiomes are also currently being researched. Hormone-induced dysbiosis after menopause is believed to have effects on physical changes and health consequences. Postmenopausal changes in the gut microbiome are associated with increased short-chain fatty acids and hydrogen sulfide levels. Increased vaginal pH caused by reduced estrogen alters the vaginal microbiome, resulting in reduced levels of Lactobacillus. Such changes influence the vaginal structure and functions, contributing to the onset of genitourinary syndrome of menopause. A dysbiosis of the urinary microbiome is associated with urgency and urinary incontinence and also related to interstitial cystitis/bladder pain syndrome and neuropathic bladder. As these diseases commonly affect postmenopausal women, hormone-induced changes in the microbiome may play a role. Menopause increases the alpha diversity of the urinary microbiome and lowers the percentage of Lactobacillus in urine, and such changes precede recurrent cystitis. More research regarding the effects of changes in the urinary microbiome due to menopause on urinary tract diseases is needed.

Microbiota Ecosystem in Recurrent Cystitis and the Immunological Microenvironment of Urothelium

Urinary tract infections (UTIs) represent one of the most frequent low genital tract diseases in the female population. When UTIs occur with a frequency of at least three times per year or two times in the last six month, we speak of recurrent UTI (rUTI) and up to 70% of women will have rUTI within 1 year. It was previously thought that antibiotic resistance was principally responsible for the recurrence of UTIs, but nowadays new diagnostic technologies have shown the role of microbiota in the pathophysiology of these diseases. Much research has been conducted on the role of gut microbiome in the development of rUTI, while little is known yet about vaginal and urinary microbiome and the possible immunological and microscopical mechanisms through which they trigger symptoms. New discoveries and clinical perspectives are arising, and they all agree that a personalized, multi-modal approach, treating vaginal and urinary dysbiosis, may reduce rUTIs more successfully.

Combined acupuncture and moxibustion therapy for the treatment of neurogenic bladder and bowel dysfunction following traumatic spinal cord injury: A case report

Neurogenic bladder and bowel are two critical autonomic complications following traumatic spinal cord injury (TSCI). Chronic lower urinary tract and bowel dysfunctions can lead to secondary complications, drastically affect the quality of life and significantly increase the risk of hospital readmission and mortality. Other than symptomatic treatments, a few effective therapies are available. Combined acupuncture and moxibustion therapy has positive effects on improving nerve repair and functional recovery in the early phases following TSCI. However, whether it is effective for TSCI-related chronic urinary and bowel dysfunctions remains unknown. This report presents the case of a 26-year-old male patient who experienced neurogenic bladder and bowel dysfunction following TSCI due to an accidental fall from height for more than 10 months and visited our department for combined acupuncture and moxibustion therapy. After 48 treatment sessions, he regained voluntary urination and defecation to a large extent. Urodynamic testing showed recovered bladder compliance and improved detrusor contractility. Symptom assessment with the Qualiveen Short-Form and neurogenic bowel dysfunction scores demonstrated reduced symptom severity. This case suggests that combined acupuncture and moxibustion therapy might help to restore the physiological functions of the lower urinary and digestive tracts following TSCI and might be a promising alternative for the treatment of neurogenic bladder and bowel dysfunction in patients with TSCI.

Interspecies relationships between nosocomial pathogens associated to preterm infants and lactic acid bacteria in dual-species biofilms

The nasogastric enteral feeding tubes (NEFTs) used to feed preterm infants are commonly colonized by bacteria with the ability to form complex biofilms in their inner surfaces. Among them, staphylococci (mainly Staphylococcus epidermidis and Staphylococcus aureus) and some species belonging to the Family Enterobacteriaceae are of special concern since they can cause nosocomial infections in this population. NETF-associated biofilms can also include lactic acid bacteria (LAB), with the ability to compete with pathogenic species for nutrients and space. Ecological interactions among the main colonizers of these devices have not been explored yet; however, such approach could guide future strategies involving the pre-coating of the inner surfaces of NEFTs with well adapted LAB strains in order to reduce the rates of nosocomial infections in neonatal intensive care units (NICUs). In this context, this work implied the formation of dual-species biofilms involving one LAB strain (either Ligilactobacillus salivarius 20SNG2 or Limosilactobacillus reuteri 7SNG3) and one nosocomial strain (either Klebsiella pneumoniae 9SNG3, Serratia marcescens 10SNG3, Staphylococcus aureus 45SNG3 or Staphylococcus epidermidis 46SNG3). The six strains used in this study had been isolated from the inner surface of NEFTs. Changes in adhesion ability of the pathogens were characterized using a culturomic approach. Species interactions and structural changes of the resulting biofilms were analyzed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). No aggregation was observed in dual-species biofilms between any of the two LAB strains and either K. pneumoniae 9SNG3 or S. marcescens 10SNG3. In addition, biofilm thickness and volume were reduced, suggesting that both LAB strains can control the capacity to form biofilms of these enterobacteria. In contrast, a positive ecological relationship was observed in the combination L. reuteri 7SNG3-S. aureus 45SNG3. This relationship was accompanied by a stimulation of S. aureus matrix production when compared with its respective monospecies biofilm. The knowledge provided by this study may guide the selection of potentially probiotic strains that share the same niche with nosocomial pathogens, enabling the establishment of a healthier microbial community inside NEFTs.

The Urogenital System’s Role in Diseases: A Synopsis

Simple Summary

The urinary tract microbiome has come under a lot of scrutiny, and this has led to the rejection of the pre-established concept of sterility in the urinary bladder. Microbial communities in the urinary tract have been implicated in the maintenance of health. Thus, alterations in their composition have also been associated with different urinary pathologies, such as urinary tract infections. For that reason, tackling the urinary microbiome of healthy individuals, as well as its involvement in disease through the proliferation of opportunistic pathogens, could open a potential field of study, leading to new insights into prevention, diagnosis, and treatment strategies for different diseases.

Abstract

The human microbiota contains ten times more microbial cells than human cells contained by the human body, constituting a larger genetic material than the human genome itself. Emerging studies have shown that these microorganisms represent a critical determinant in human health and disease, and the use of probiotic products as potential therapeutic interventions to modulate homeostasis and treat disease is being explored. The gut is a niche for the largest proportion of the human microbiota with myriad studies suggesting a strong link between the gut microbiota composition and disease development throughout the body. More specifically, there is mounting evidence on the relevance of gut microbiota dysbiosis in the development of urinary tract disease including urinary tract infections (UTIs), chronic kidney disease, and kidney stones. Fewer emerging reports, however, are suggesting that the urinary tract, which has long been considered ‘sterile’, also houses its unique microbiota that might have an important role in urologic health and disease. The implications of this new paradigm could potentially change the therapeutic perspective in urological disease.

How to Prevent Catheter-Associated Urinary Tract Infections: A Reappraisal of Vico's Theory-Is History Repeating Itself?

New, contextualized modern solutions must be found to solve the dilemma of catheter-associated urinary infection (CAUTI) in long-term care settings. In this paper, we describe the etiology, risk factors, and complications of CAUTI, explore different preventive strategies proposed in literature from the past to the present, and offer new insights on therapeutic opportunities. A care bundle to prevent CAUTI mainly consists of multiple interventions to improve clinical indications, identifying a timeline for catheter removal, or whether any alternatives may be offered in elderly and frail patients suffering from chronic urinary retention and/or untreatable urinary incontinence. Among the various approaches used to prevent CAUTI, specific urinary catheter coatings according to their antifouling and/or biocidal properties have been widely investigated. Nonetheless, an ideal catheter offering holistic antimicrobial effectiveness is still far from being available. After pioneering research in favor of bladder irrigations or endovesical instillations was initially published more than 50 years ago, only recently has it been made clear that evidence supporting their use to treat symptomatic CAUTI and prevent complications is needed.

Catheter-Associated Urinary Tract Infections: Current Challenges and Future Prospects

Catheter-associated urinary tract infection (CAUTI) is the most common healthcare-associated infection and cause of secondary bloodstream infections. Despite many advances in diagnosis, prevention and treatment, CAUTI remains a severe healthcare burden, and antibiotic resistance rates are alarmingly high. In this review, current CAUTI management paradigms and challenges are discussed, followed by future prospects as they relate to the diagnosis, prevention, and treatment. Clinical and translational evidence will be evaluated, as will key basic science studies that underlie preventive and therapeutic approaches. Novel diagnostic strategies and treatment decision aids under development will decrease the time to diagnosis and improve antibiotic accuracy and stewardship. These include several classes of biomarkers often coupled with artificial intelligence algorithms, cell-free DNA, and others. New preventive strategies including catheter coatings and materials, vaccination, and bacterial interference are being developed and investigated. The antibiotic pipeline remains insufficient, and new strategies for the identification of new classes of antibiotics, and rational design of small molecule inhibitor alternatives, are under development for CAUTI treatment.

Recent insights into catheter-related urinary tract infections

Urinary tract infections (UTIs) commonly develop in people with urinary catheters. Inserting a catheter can damage the urothelial barrier and trigger the formation of a biofilm on the catheter that allows bacteria direct access to the bladder. Biofilms also protect bacteria from the immune system and reduce antibiotic effectiveness. In addition, a growing literature suggests that the urinary tract harbours bacteria even in people with negative conventional cultures. The urinary microbiome is highly individual. Nevertheless, changes in the urinary microbiome may identify individuals at risk of UTIs and, for example, suggest that a catheter should be replaced more frequently and, in turn, avoid the need for antibiotics. This article outlines the importance of biofilms in the development of catheter-related UTIs and introduces the urinary microbiome.

Distinguishing Features of the Urinary Bacterial Microbiome in Patients with Neurogenic Lower Urinary Tract Dysfunction

PURPOSE

We aimed to characterize the urinary microbiome of catheterizing patients with neurogenic lower urinary tract dysfunction (NLUTD) and to evaluate differences based on type of bladder management or frequency of urinary tract infections.

MATERIALS AND METHODS

This is a prospective, cross-sectional study of urine samples from asymptomatic, catheterizing patients with neurogenic lower urinary tract dysfunction who used either clean intermittent catheterization or indwelling catheters. Patients without symptoms of urinary tract infection provided a catheterized urine sample for urinalysis, culture and bacterial community microbiome analysis.

RESULTS

A total of 95 patients submitted urine for analysis, of whom 69 had sufficient sequence reads (>1,203) for microbiome analysis. Cases with low bacterial signal amplification were associated with use of vaginal estrogen, no intradetrusor botulinum toxin A use and no growth on standard urine culture. The most abundant operational taxonomic units were from the phylum Proteobacteria, classified as Enterobacteriaceae and Escherichia. Alpha diversity varied among those who used indwelling catheters vs clean intermittent catheterization, and those who underwent botulinum toxin A injection vs not. On linear discriminate analysis, the relative abundance of the operational taxonomic units identified as Pseudomonas was higher among patients using indwelling catheters relative to clean intermittent catheterization. The operational taxonomic unit identified as Aerococcus was at a higher relative abundance among males compared to females.

CONCLUSIONS

Enterobacteriaceae and Escherichia were the most abundant genera in the urinary microbiome of patients with neurogenic lower urinary tract dysfunction. Urinary microbiome diversity varied based on bladder management type. Future clinical correlations between microbiome of neurogenic patients and clinical presentation may help guide treatment strategies.

Systematic review of the changes in the microbiome following spinal cord injury: animal and human evidence

Study design

Systematic review.

Objectives

To investigate the changes in the microbiome among human and animal populations with spinal cord injury (SCI).

Methods

Four databases (EMBASE, Medline (Ovid), Web of Science, Cochrane Central Register of Trials (CENTRAL)) and Google Scholar were searched. No language restrictions were applied. Data extraction was done in parallel and independently by two reviewers. The search was last conducted on 07 April 2021.

Results

There were 6869 studies retrieved, 43 full-text studies reviewed, and 19 studies included. There were seven animal gut studies, six human gut studies, and six urinary tract studies identified. There were no publications found on other body sites. Among the included studies, we observed a consistent and significant difference in gut microbiome composition between populations with SCI and able-bodied populations. This is characterized by a decrease in beneficial butyrate-producing bacteria (Faecalbacterium, Megamonas, Roseburia) and an increase in inflammation-associated bacteria (Alistipes, Anaerotruncus, and Lachnoclostridium). On the other hand, the urine of individuals with SCI was polymicrobial and members of Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae) were frequently observed. Probiotics were shown to induce a significant but transient shift in the urinary tract microbiome. The studies had low to moderate risks of bias.

Conclusions

There are limited studies on the changes in microbiome among SCI populations. The gut microbiome was characterized by bacterial profiles associated with chronic inflammation and metabolic disorder while the studies of the urinary tract microbiome show the dominance of bacterial genera associated with urinary tract infection.

Recurrent Urinary Tract Infections and Asymptomatic Bacteriuria in Adults

Purpose of review

Our goal was to summarize recent evidence regarding recurrent urinary tract infections and asymptomatic bacteriuria in different adult populations.

Recent findings

Several research groups are focused on the description of resident bacterial flora in the bladder and urinary dysbiosis in the microbiome era. Even the definitions might change in light of these discoveries. However, the role of urinary microbiome and bacterial interference has still to be determined.

Summary

Systematic treatment of asymptomatic bacteriuria is not recommended and even classic indications such as asymptomatic bacteriuria in pregnant women are controversial. In fact, its treatment is associated with a higher probability of symptomatic UTI and a higher prevalence of antibiotic-resistant bacteria. Improving the diagnosis of asymptomatic bacteriuria and optimizing the management of recurrent urinary tract infections, especially through non-antibiotics measures, are needed in order to minimise antimicrobial resistance.

Risk factors in bacterial colonization of internal ureteral stent

A ureteral stent is most broadly used to manage upper urinary tract disorders such as obstruction and prevent post-endoscopic complications. However, the stent may become a niche for bacterial colonization. This study aimed to determine the rate of bacterial colonization and type of bacteria in internal ureteral stents and the risk factors associated with bacterial colonization. This prospective cross-sectional study included 100 consecutive adult patients who had temporary ureteral stenting as preparation for a secondary ureterorenoscopy at Al-Yarmook Hospital/ Baghdad. All included patients were negative for bacterial culture before stenting. Stent and urine culture were performed at the time of stent removal. The colonization rate and bacteriuria in patients with internal ureteral stent were 19% and 9%, respectively. The most common bacteria in-stent and urine were E. coli accounting for 31.58% and 33.33%. Pseudomonas aeruginosa was common in stent culture, representing 21.05%. Positive bacterial culture was confirmed in 19 stents and 9 urine samples. All cases with positive urine samples were also positive for culture. Thus, the sensitivity and specificity of urine culture for detection of stent colonization were 47.37% and 100%, respectively. Diabetes mellitus, chronic renal failure, and prolonged stenting were significantly associated with increased stent colonization. The ureteral stent could be a source of urinary tract infection. The most pathogenic bacteria associated with the ureter stent are E. coli and Pseudomonas aeruginosa. Risk factors associated with stent colonization are diabetes mellitus, chronic renal failure, and prolonged indwelling time.

Surgical Management of Charcot Spinal Arthropathy in the Face of Possible Infection

BACKGROUND

The design is a retrospective cohort study. Charcot spinal arthropathy (CSA) is a rare and poorly understood progressive destructive spine condition that usually affects patients with preexisting spinal cord injury. The complexity of this condition, especially when additionally burdened by superimposed infection in the CSA zone, can potentially lead to suboptimal management such as protracted antibiotic therapy, predisposition to hardware failure, and pseudarthrosis. While in noninfected CSA primary stabilization is the major goal, staged surgical management has not been stratified based upon presence of a superinfected CSA. We compare clinical and radiological outcomes of surgical treatment in CSA patients with and without concurrent spinal infections.

METHODS

Our single-institution database was reviewed for all patients diagnosed with CSA and surgically treated, who were subsequently divided into 2 cohorts: spinal arthropathy with superimposed infection and those without. Those were comparatively studied for complications and reoperation rate.

RESULTS

Fifteen patients with CSA underwent surgical intervention; mean follow up of 15.3 months (range, 0-43). Eleven patients received stabilization with a quadruple-rod thoracolumbopelvic construct, while 4 patients with superinfected CSA underwent a staged procedure. Patients treated with a staged approach experienced fewer intraoperative complications (0% versus 18%) and fewer revision surgeries (25% versus 36%). Both cohorts had the same eventual healing.

CONCLUSIONS

Surgical management in CSA patients with primary emphasis on stability and modified surgical treatment based on presence of an active infection in the zone of neuropathic destruction will lead to similar eventual successful results with relatively few and manageable complications in this challenging patient population.

LEVEL OF EVIDENCE

4.

CLINICAL RELEVANCE

The proposed treatment algorithm including the use of a quadruple-rod construct with lumbopelivic fixation and a staged approach in patients with superinfected CSA represents a reasonable option in the surgical treatment of CSA.

Actinotignum schaalii: Relation to Concomitants and Connection to Patients' Conditions in Polymicrobial Biofilms of Urinary Tract Catheters and Urines

Actinotignum schaalii is an emerging, opportunistic pathogen and its connection to non-infectious diseases and conditions, such as prostate or bladder cancer, or chronic inflammation has been proposed. Here, we analyzed 297 urine, ureteral and urinary catheter samples from 128 patients by Polymerase Chain Reaction followed by Denaturing Gradient Gel Electrophoresis and Sequencing (PCR-DGGE-S), and culture, and 29 of these samples also by 16S rRNA Illumina sequencing, to establish A. schaalii’s prevalence in urinary tract-related samples, its relation to other bacteria, and its potential association with patients’ conditions and samples’ characteristics. A. schaalii-positive samples were significantly more diverse than A. schaalii negative and between-group diversity was higher than intra-group. Propionimicrobium lymphophilum, Fusobacterium nucleatum, Veillonella sp., Morganella sp., and Aerococcus sp. were significantly more often present in A. schaalii-positive samples; thus, we suggest these species are A. schaalii’s concomitants, while Enterobacter and Staphylococcaceae were more often identified in A. schaalii-negative samples; therefore, we propose A. schaalii and these species are mutually exclusive. Additionally, a significantly higher A. schaalii prevalence in patients with ureter stricture associated hydronephrosis (p = 0.020) was noted. We suggest that A. schaalii could be an early polybacterial biofilm colonizer, together with concomitant species, known for pro-inflammatory features.

Polymicrobial interactions in the urinary tract: is the enemy of my enemy my friend?

The vast majority of research pertaining to urinary tract infection has focused on a single pathogen in isolation, and predominantly Escherichia coli. However, polymicrobial urine colonization and infection are prevalent in several patient populations, including individuals with urinary catheters. The progression from asymptomatic colonization to symptomatic infection and severe disease is likely shaped by interactions between traditional pathogens as well as constituents of the normal urinary microbiota. Recent studies have begun to experimentally dissect the contribution of polymicrobial interactions to disease outcomes in the urinary tract, including their role in development of antimicrobial-resistant biofilm communities, modulating the innate immune response, tissue damage, and sepsis. This review aims to summarize the epidemiology of polymicrobial urine colonization, provide an overview of common urinary tract pathogens, and present key microbe-microbe and host-microbe interactions that influence infection progression, persistence, and severity.

The gut-brain axis and beyond: Microbiome control of spinal cord injury pain in humans and rodents

Spinal cord injury (SCI) is a devastating injury to the central nervous system in which 60 to 80% of patients experience chronic pain. Unfortunately, this pain is notoriously difficult to treat, with few effective options currently available. Patients are also commonly faced with various compounding injuries and medical challenges, often requiring frequent hospitalization and antibiotic treatment. Change in the gut microbiome from the "normal" state to one of imbalance, referred to as gut dysbiosis, has been found in both patients and rodent models following SCI. Similarities exist in the bacterial changes observed after SCI and other diseases with chronic pain as an outcome. These changes cause a shift in the regulation of inflammation, causing immune cell activation and secretion of inflammatory mediators that likely contribute to the generation/maintenance of SCI pain. Therefore, correcting gut dysbiosis may be used as a tool towards providing patients with effective pain management and improved quality of life.

The Role of Gut, Vaginal, and Urinary Microbiome in Urinary Tract Infections: From Bench to Bedside

The current paradigm of urinary tract infection (UTI) pathogenesis takes into account the contamination of the periurethral space by specific uropathogens residing in the gut, which is followed by urethral colonization and pathogen ascension to the urinary bladder. Consequently, studying the relationship between gut microbiota and the subsequent development of bacteriuria and UTI represents an important field of research. However, the well-established diagnostic and therapeutic paradigm for urinary tract infections (UTIs) has come into question with the discovery of a multifaceted, symbiotic microbiome in the healthy urogenital tract. More specifically, emerging data suggest that vaginal dysbiosis may result in Escherichia coli colonization and prompt recurrent UTIs, while urinary microbiome perturbations may precede the development of UTIs and other pathologic conditions of the urinary system. The question is whether these findings can be exploited for risk reduction and treatment purposes. This review aimed to appraise the three aforementioned specific microbiomes regarding their potential influence on UTI development by focusing on the recent studies in the field and assessing the potential linkages between these different niches, as well as evaluating the state of translational research for novel therapeutic and preventative approaches.

Optimizing the Catheter Care and Maintenance Strategy of Short-Term Catheterization among Hospitalized Patients in Microbiological Approach

OBJECTIVE

To optimize the allocation of nursing resources, we investigate an alternative strategy for indwelling catheter cleaning.

METHODS

The present study involved a total of 117 male patients and 54 female patients, who were catheterized after urinary surgery from Aug 2018 to Feb 2019. The samples of indwelling catheter cleaning solutions were divided by two parts for microbiological culture and microbiome analysis.

RESULTS

No pathogenic bacteria were observed in the microbiological culture of the indwelling catheter cleaning samples from 24 h-uncleaned group and 48 h-uncleaned group. The microbiome analysis also showed no significant difference in bacterial diversity and quantity of the indwelling catheter cleaning solutions between the two groups.

CONCLUSION

The indwelling catheter cleaning for male after urinary surgery can be prolonged to 48 h. The result of this study provided reliable basis for optimizing the allocation of clinical nursing resources.

Microbiome studies in urology- where do we stand and where can we reach?

The role of microbiome milieu in the urinary tract, their interplay in diverse urological conditions and their therapeutic implications are not completely understood. The microbiome has contributed towards urinary tract infections, urolithiasis and urological cancers. The possibility of manipulating microbiome for diagnosis and treatment is evolving. Probiotics might help in overcoming the problems of recurrent infection and antibiotic resistance. Novel applications like stents and catheters coated with non-pathogenic organisms are being developed. Research in the urinary microbiome has progressed from using mouse models to the presently available three- dimensional cultured organoids, thus making it more feasible. As our knowledge regarding the urinary microbiome increases, justice can be done to many patients in whom the advancements can be used for prophylaxis, diagnosis, treatment and even in improving their quality of life. The growing amount of antibiotic resistance is also a matter of concern and probiotics might be the answer to this upcoming calamity. In this review, we have discussed the role of the urinary microbiome in pathogenesis, diagnosis and treatment of urological conditions and pondered upon its future prospects.

A cross-sectional analysis of the urine microbiome of children with neuropathic bladders

BACKGROUND

Distinguishing a urinary tract infection (UTI) from asymptomatic bacteriuria (ASB) in children with neuropathic bladders is difficult. Currently used markers of infection, such as the routine urinalysis, lack specificity for UTI in this population. The urinary microbiome may help differentiate these states.

OBJECTIVE

The objective of this work was to describe the baseline microbiome in children with neuropathic bladders, and to determine if differences exist among the urine microbiomes of children with neuropathic bladders who have negative urine cultures, ASB, or UTI.

STUDY DESIGN

This is a cross-sectional study of children with neuropathic bladders who use clean intermittent catheterization for bladder management who had a urine culture sent as part of clinical management. Residual urine, initially collected via catheter for urine culture, was obtained for use in this work. Microbial DNA was isolated, and the V4 region of the 16SrRNA gene sequenced. The relative abundance of each bacteria was measured in each group. Alpha diversity, measured by Chao1 and the Shannon Diversity Index, was also measured in each group. PERMANOVA was used to compare the microbiota between groups.

RESULTS

36 children with neuropathic bladders were included in this study (UTI = 11, ASB = 19, negative cultures = 4). The most abundant bacteria were unspecified Enterobacteriaceae, Klebsiella, Staphylococcus, Streptococcus, and Enterococcus. Children who catheterize their urethra have a higher proportion of Staphylococcus, while the urine microbiome of those who catheterize through a Mitrofanoff consists predominantly of members of the family Enterobacteriaceae. Given the low numbers of patients with Mitrofanoffs and augmented bladders, we did not statistically compare the urine microbiomes between these patients. There was no difference in either alpha diversity or the overall microbiota between children with neuropathic bladders with UTI, ASB, and negative cultures.

DISCUSSION

In this pilot cohort of children with neuropathic bladders, bacteria that are members of the family Enterobacteriaceae are the most predominant bacteria in the urine microbiomes. There was no difference in the urine microbiome between those with UTI, ASB, and negative cultures. Route of catheterization may affect the composition of the urine microbiome, although due to limited sample size, this was not confirmed statistically.

CONCLUSION

There was no difference in the urine microbiome between patients with negative urine cultures, ASB, and UTI. Further work is needed to determine if the urine microbiome varies based on either the route of catheterization or the presence of augmented bladder.

Ureteral Stent Microbiota Is Associated with Patient Comorbidities but Not Antibiotic Exposure

Ureteral stents are commonly used to prevent urinary obstruction but can become colonized by bacteria and encrusted, leading to clinical complications. Despite recent discovery and characterization of the healthy urinary microbiota, stent-associated bacteria and their impact on encrustation are largely underexplored. We profile the microbiota of patients with typical short-term stents, as well as over 30 atypical cases (all with paired mid-stream urine) from 241 patients. Indwelling time, age, and various patient comorbidities correlate with alterations to the stent microbiota composition, whereas antibiotic exposure, urinary tract infection (UTI), and stent placement method do not. The stent microbiota most likely originates from adhesion of resident urinary microbes but subsequently diverges to a distinct, reproducible population, thereby negating the urine as a biomarker for stent encrustation or microbiota. Urological practice should reconsider standalone prophylactic antibiotics in favor of tailored therapies based on patient comorbidities in efforts to minimize bacterial burden, encrustation, and complications of ureteral stents.

Diagnosis of Urinary Tract Infection in the Neuropathic Bladder: Changing the Paradigm to Include the Microbiome

Bacteriuria, a non-specific term that refers to the presence of bacteria in the urine, is common in people with neuropathic bladders. However, accurately determining when bacteriuria represents a urinary tract infection (UTI) as opposed to asymptomatic bacteriuria is difficult. There is currently no widely accepted definition of what constitutes a UTI in people with neuropathic bladders. As a result, there is significant variation in care, which likely leads to unnecessary use of antibiotics for bacteriuria. To improve the clinical management of people with neuropathic bladders, it is important to be able to accurately diagnose and treat UTIs. In this article, we review the difficulties associated with accurately diagnosing UTIs and then review proposed definitions. Finally, we discuss the emerging literature of the urinary microbiome and how this may assist in accurately diagnosing UTIs in people with neuropathic bladders.

Urinary Catheter-Associated Infections

Catheter-associated urinary tract infection remains one of the most prevalent, yet preventable, health care-associated infections. General prevention strategies include strict adherence to hand hygiene and antimicrobial stewardship. Duration of urinary catheterization is the most important modifiable risk factor. Targeted prevention strategies include limiting urinary catheter use; physician reminder systems, nurse-initiated discontinuation protocols, and automatic stop orders have successfully decreased catheter duration. Alternatives should be considered. If catheterization is necessary, proper aseptic practices for insertion and maintenance and closed catheter collection systems are essential for prevention. The use of bladder bundles and collaboratives aids in the effective implementation of prevention measures.

Premenopausal women with recurrent urinary tract infections have lower quality of life

OBJECTIVES

To examine the impact on quality of life of recurrent acute uncomplicated urinary tract infection among premenopausal Singaporean women, and to determine the risk factors for lower quality of life among these patients.

METHODS

A total of 85 patients with recurrent acute uncomplicated urinary tract infection who were referred to the Urology Department at the National University Hospital, Singapore, were prospectively recruited over a 3-year period to complete the validated Short Form 36 Health Survey version 1. In addition, demographic and clinical details including symptomology and medical history were analyzed for factors impacting quality of life. Short Form 36 Health Survey version 1 results were compared with published population norms.

RESULTS

After adjusting for age, gender and race, recurrent acute uncomplicated urinary tract infection patients had significantly lower quality of life on seven out of eight Short Form 36 Health Survey version 1 domains when compared with age-, gender- and race-adjusted population norms for Singapore. Among those with recurrent acute uncomplicated urinary tract infection, those who also reported caffeine consumption had significantly lower Short Form 36 Health Survey version 1 scores than those who did not. Those who reported chronic constipation also had consistently lower Short Form 36 Health Survey version 1 scores across all domains.

CONCLUSIONS

Recurrent acute uncomplicated urinary tract infection has a negative impact on the quality of life of premenopausal, otherwise healthy women. Recurrent acute uncomplicated urinary tract infection patients who also have chronic constipation or consume caffeine have lower quality of life than those who do not. More studies are required to understand the relationships between these common problems and risk factors.

The Role of the Genitourinary Microbiome in Pediatric Urology: a Review

PURPOSE OF REVIEW

In this review, we highlight the effects of the microbiome on urologic diseases that affect the pediatric patient.

RECENT FINDINGS

Perturbations in the urinary microbiome have been shown to be associated with a number of urologic diseases affecting children, namely urinary tract infection, overactive bladder/urge urinary incontinence, and urolithiasis. Recently, improved cultivation and sequencing technologies have allowed for the discovery of a significant and diverse microbiome in the bladder, previously assumed to be sterile. Early studies aimed to identify the resident bacterial species and demonstrate the efficacy of sequencing and enhanced quantitative urine culture. More recently, research has sought to elucidate the association between the microbiome and urologic disease, as well as to demonstrate effects of manipulation of the microbiome on various urologic pathologies. With an improved appreciation for the impact of the urinary microbiome on urologic disease, researchers have begun to explore the impact of these resident bacteria in pediatric urology.