Antimicrobial resistance among uropathogens that cause community-acquired urinary tract infections in women: a nationwide analysis

Antibiotics for UTI Prevention After Intradetrusor OnabotulinumtoxinA Injections

IMPORTANCE

Urinary tract infections (UTIs) occur in 8.6% to 48.1% of patients after intradetrusor onabotulinumtoxinA injections.

OBJECTIVE

The objective of this study was to evaluate both choice and duration of antibiotic prophylaxis on the incidence of UTI within 30 days after in-office onabotulinumtoxinA injections.

STUDY DESIGN

We included a single-site, retrospective cohort of 305 patients with overactive bladder or bladder pain syndrome receiving postprocedure prophylactic antibiotics for in-office, 100-unit intradetrusor onabotulinumtoxinA injections from 2019 to 2023. Categories of antibiotic prophylaxis compared included (1) nitrofurantoin 100 mg twice daily for 3 days, (2) nitrofurantoin 100 mg twice daily for 5 days, (3) trimethoprim-sulfamethoxazole 160 mg/800 mg twice daily for 3 days, and (4) "other regimens." Primary outcome was incidence of UTI within 30 days. Variables were compared via χ2 test. Crude/adjusted odds were estimated using binary logistic regression.

RESULTS

Incidence of UTI was 10.4% for 3-day nitrofurantoin, 20.5% for 5-day nitrofurantoin, 7.4% for 3-day trimethoprim-sulfamethoxazole, and 25.7% among "other regimens" (P = 0.023). Differences among primary regimens were substantial but not statistically significant: 3-day trimethoprim-sulfamethoxazole had 31% lower odds of UTI versus 3-day nitrofurantoin (odds ratio [OR], 0.689; P = 0.518). Compared with 3-day nitrofurantoin regimen, the 5-day nitrofurantoin regimen had twice the odds of UTI (OR, 2.22; P = 0.088). Those receiving "other regimens" had nearly 3 times the odds of UTI (OR, 2.98; P = 0.018). Results were similar adjusting for age and race. Overall urinary retention rate was 1.97%.

CONCLUSIONS

Prophylactic antibiotic choice and duration of treatment potentially affect UTI incidence after in-office, intradetrusor onabotulinumtoxinA injections. Nitrofurantoin and trimethoprim-sulfamethoxazole for 3 days have the lowest UTI incidence.

Prevalence of urinary tract infections and risk factors among diabetic patients in Ethiopia, a systematic review and meta-analysis

INTRODUCTION

Urinary tract infection (UTI) is a common clinical problem that comprises 1-6% of medical referrals and includes urinary tract, bladder, and kidney infections. UTI is the most commonly occurring infectious disease in diabetic patients. Therefore, this systematic review and meta-analysis aimed to estimate the prevalence of urinary tract infection and its associated factors in Ethiopia.

METHODS

The online libraries of PubMed, Google Scholar, Scopus, and Science Direct, were searched. Data were extracted using Microsoft Excel and analyzed using STATA statistical software (v. 16). Forest plots, Begg's rank test, and Egger's regression test were all used to check for publication bias. To look for heterogeneity, I2 was computed, and an overall estimated analysis was carried out. Subgroup analysis was done by region, and publication year. Meta-regression analysis using study-level covariates as predictors of study-level estimates to explore the determinants of potential heterogeneity in our pooled estimates. The pooled odds ratio for related covariates was also calculated.

RESULTS

Out of 1128 studies assessed, 14 met our criteria and were included in the study. A total of 3773 people were included in the study. The prevalence of urinary tract infection was estimated to be 15.97% (95% CI: 12.72-19.23). According to subgroup analysis, the highest prevalence was observed in the SNNP region (19.21%) and studies conducted in and after 2018 (17.98%). Being female (AOR = 3.77; 95% CI: 1.88, 5.65), being illiterate (AOR = 5.29; 95% CI: 1.98, 8.61), prior urinary tract infection history (AOR = 3.04; 95% CI: 2.16-3.92) were the predictor of urinary tract infection.

CONCLUSION

The prevalence of urinary tract infections was high in Ethiopia. Female gender, illiteracy, and prior UTI history were associated with urinary tract infections. Since UTIs in diabetic patients has serious medical and public health consequence, screening of UTIs in diabetic patients and early initiation of treatment should become a public health priority.

Lactic acid bacteria: prominent player in the fight against human pathogens

INTRODUCTION

The human microbiome is a unique repository of diverse bacteria. Over 1000 microbial species reside in the human gut, which predominantly influences the host's internal environment and plays a significant role in host health. Lactic acid bacteria have long been employed for multiple purposes, ranging from food to medicines. Lactobacilli, which are often used in commercial food fermentation, have improved to the point that they might be helpful in medical applications.

AREAS COVERED

This review summarises various clinical and experimental evidence on efficacy of lactobacilli in treating a wide range of infections. Both laboratory based and clinical studies have been discussed.

EXPERT OPINION

Lactobacilli are widely accepted as safe biological treatments and host immune modulators (GRAS- Generally regarded as safe) by the US Food and Drug Administration and Qualified Presumption of Safety. Understanding the molecular mechanisms of lactobacilli in the treatment and pathogenicity of bacterial infections can help with the prediction and development of innovative therapeutics aimed at pathogens which have gained resistance to antimicrobials. To formulate effective lactobacilli based therapy significant research on the effectiveness of different lactobacilli strains and its association with demographic distribution is required. Also, the side effects of such therapy needs to be evaluated.

Diabetes Mellitus as a Predictive Factor for Urinary Tract Infection for Patients Treated with Kidney Transplantation

Background and Objectives: We aimed to investigate the rate of incidence and risk factors of post-transplant urinary tract infection (UTI) in patients receiving kidney transplantation (KT) at our institution. Materials and Methods: A retrospective cohort study was carried out on patients who underwent KT for end-stage kidney disease (ESKD) from January 2008 to December 2021 at Gifu University Hospital. UTI was defined as the existence of bacterial and/or fungal infection in urine with ≥105 colony-forming units/mL, with or without urinary and/or systemic symptoms of UTI. Patients were divided into two groups: those with UTI after KT (UTI group) and those without UTI (non-UTI group). The primary endpoint of this study was the relationship between covariates and UTI after KT. Results: Two hundred and forty patients with ESKD received KT at Gifu University Hospital. Thirty-four participants developed UTI after surgery, and the most common pathogen was Escherichia coli. At the end of the follow-up, graft loss was observed in six patients (2.5%), independent of UTI episodes. In the multivariate analysis, diabetes mellitus (DM) was statistically associated with post-transplant UTI in kidney transplant recipients. Conclusions: Preoperative serum glucose control in patients with DM may have a crucial role in preventing UTI and preserving renal function after KT.

Conserved FimK Truncation Coincides with Increased Expression of Type 3 Fimbriae and Cultured Bladder Epithelial Cell Association in Klebsiella quasipneumoniae

Klebsiella spp. commonly cause both uncomplicated urinary tract infection (UTI) and recurrent UTI (rUTI). Klebsiella quasipneumoniae, a relatively newly defined species of Klebsiella, has been shown to be metabolically distinct from Klebsiella pneumoniae, but its type 1 and type 3 fimbriae have not been studied. K. pneumoniae uses both type 1 and type 3 fimbriae to attach to host epithelial cells. The type 1 fimbrial operon is well conserved between Escherichia coli and K. pneumoniae apart from fimK, which is unique to Klebsiella spp. FimK contains an N-terminal DNA binding domain and a C-terminal phosphodiesterase (PDE) domain that has been hypothesized to cross-regulate type 3 fimbriae expression via modulation of cellular levels of cyclic di-GMP. Here, we find that a conserved premature stop codon in K. quasipneumoniae fimK results in truncation of the C-terminal PDE domain and that K quasipneumoniae strain KqPF9 cultured bladder epithelial cell association and invasion are dependent on type 3 but not type 1 fimbriae. Further, we show that basal expression of both type 1 and type 3 fimbrial operons as well as cultured bladder epithelial cell association is elevated in KqPF9 relative to uropathogenic K. pneumoniae TOP52. Finally, we show that complementation of KqPF9ΔfimK with the TOP52 fimK allele reduced type 3 fimbrial expression and cultured bladder epithelial cell attachment. Taken together these data suggest that the C-terminal PDE of FimK can modulate type 3 fimbrial expression in K. pneumoniae and its absence in K. quasipneumoniae may lead to a loss of type 3 fimbrial cross-regulation. IMPORTANCE K. quasipneumoniae is often indicated as the cause of opportunistic infections, including urinary tract infection, which affects >50% of women worldwide. However, the virulence factors of K. quasipneumoniae remain uninvestigated. Prior to this work, K. quasipneumoniae and K. pneumoniae had only been distinguished phenotypically by metabolic differences. This work contributes to the understanding of K. quasipneumoniae by evaluating the contribution of type 1 and type 3 fimbriae, which are critical colonization factors encoded by all Klebsiella spp., to K. quasipneumoniae bladder epithelial cell attachment in vitro. We observe clear differences in bladder epithelial cell attachment and regulation of type 3 fimbriae between uropathogenic K. pneumoniae and K. quasipneumoniae that coincide with a structural difference in the fimbrial regulatory gene fimK.

Can Urinalysis and Past Medical History of Kidney Stones Predict Urine Antibiotic Resistance?

Introduction

Urinary tract infections (UTI) are one of the most common infections encountered in the emergency department (ED) with an estimated 2–3 million annual visits. Commonly prescribed antibiotics for UTIs have shown growing rates of resistance. Previous studies lack direction on improving UTI treatment based on the labs available to the bedside clinician.

Methods

We sought to determine if antibiotic resistance in UTIs was related to demographics, urinalysis, and history of renal failure or kidney stones. We conducted an analysis of 892 women ≥18 years of age discharged from the ED with a UTI diagnosis. We assessed predictors of nitrofurantoin resistance, cefazolin resistance, ciprofloxacin resistance, and trimethoprim-sulfamethoxazole resistance using unadjusted and multivariable logistic regression models.

Results

Antibiotic resistance was 13.6% for nitrofurantoin, 11.9% for cefazolin, 12.8% for ciprofloxacin, and 17.1% for trimethoprim-sulfamethoxazole. In multivariable analysis, significant independent associations with an increased likelihood of resistance to nitrofurantoin were observed for less urine blood (OR [per 1 category increase of score] 0.81; P = 0.02); greater mucous (OR [per 1 category increase of score] 1.22; P = 0.02); less specific gravity urine (OR [per 1 category increase] 0.87; P = 0.04), and presence of any history of kidney stones (OR 3.24; P = 0.01). There were no significant predictors for cefazolin resistance (all P ≥0.06); age was the only significant predictor of ciprofloxacin resistance (OR per 10 year increase] 1.10, P = 0.05), and lower specific gravity urine was significantly associated with an increased risk of resistance to trimethoprim- sulfamethoxazole (OR [per 1 category increase] 0.88, P = 0.04).

Conclusion

Women with any history of kidney stones may have bacteriuria resistant to nitrofurantoin, suggesting that providers might consider alternative antibiotic therapies in this scenario.

Does the COVID Pandemic Modify the Antibiotic Resistance of Uropathogens in Female Patients? A New Storm?

Urinary tract infections (UTIs) represent a common pathology among female patients, leading to overprescribing antibiotics, globally. The emergence of the COVID-19 pandemic has dramatically increased the incidence of this particular viral pneumonia with secondary bacterial superinfection, resulting in continuous therapeutic or prophylactic recommendations of antibiotic treatment; thus, an updated analysis of current antimicrobial resistance among uropathogens is mandatory. This cross-sectional retrospective study conducted in two university hospitals in Bucharest, Romania analyzed 2469 positive urine cultures, among two different periods of 6 months, before and during the COVID-19 pandemic. The most common pathogen was Escherichia coli 1505 (60.95%), followed by Klebsiella spp. 426 (17.25%). Enterococcus spp. was the leading Gram-positive pathogen 285 (11.54%). In gram negative bacteria, in almost all cases, an increased in resistance was observed, but the highest increase was represented by quinolones in Klebsiella spp., from 16.87% to 35.51% and Pseudomonas from 30.3% to 77.41%; a significant increase in resistance was also observed for carbapenems. Surprisingly, a decrease in resistance to Penicillin was observed in Enterococcus spp., but the overall tendency of increased resistance is also maintained for gram positive pathogens. The lack of data on the influence of the COVID-19 pandemic on uropathogens’ resistance promotes these findings as important for every clinician treating UTIs and for every specialist in the medical field in promoting reasonable recommendations of antibiotic therapies.

The prevalence of urinary tract infections in type 2 diabetic patients: a systematic review and meta-analysis

Background

Urinary tract infection is the most common infection in type 2 diabetic patients. Various studies have reported different outbreaks of urinary tract infections in type 2 diabetic patients. Therefore, the present study aimed to determine the prevalence of urinary tract infections in type 2 diabetic patients during a systematic review and meta-analysis in order to develop interventions to reduce the incidence of urinary tract infections in type 2 diabetic patients.

Methods

In this study, systematic review and meta-analysis of study data related to the prevalence of urinary tract infection in type 2 diabetic patients were conducted using keywords including type 2 diabetes, urinary tract infection, diabetes, prevalence, meta-analysis and their English equivalents in SID, MagIran, IranMedex, IranDoc, Google Scholar, Cochrane, Embase, Science Direct, Scopus, PubMed and Web of Science (WoS) databases from 1993 to 2020. In order to perform the analysis of qualified studies, the model of random-effects was used, and the inconsistency of studies with the I2 index was investigated. Data analysis was performed with Comprehensive Meta-Analysis (Version 2).

Results

Based on a total of 15 studies with a sample size of 827,948 in meta-analysis, the overall prevalence of urinary tract infection in patients with type 2 diabetes was 11.5% (95% confidence interval: 7.8–16.7%). The prevalence of urinary tract infections in diabetic Iranian patients increased with increasing number of years of research, (p < 0.05), and with increasing age of participants (p < 0.05), but however the prevalence decreased with increasing sample size (p < 0.05).

Conclusion

This study shows that urinary tract infections are highly prevalent in patients with type 2 diabetes. Therefore, due to the growing prevalence of diabetes and its complications such as urinary tract infections, the need for appropriate screening programs and health care policies is becoming more apparent.

Efficacy of vaccination with StroVac for recurrent urinary tract infections in women: a comparative single-centre study

PURPOSE

To assess the efficacy of prophylaxis for urinary tract infections (UTI) in a two-year follow-up in women with StroVac compared to a therapy with Nitrofurantoin over three months.

MATERIALS AND METHODS

All patients with documented recurrent urinary tract infections (rUTI) were offered vaccination with StroVac or therapy with three months Nitrofurantoin 100 mg once daily for three months at patient's choice. Only patients with a follow-up of at least 24 months were included. All episodes with signs of UTI were documented and urine culture was performed. Success was defined as one or none UTI per 12 months, documented by urine culture. StroVac booster injection was offered 12 months after primary vaccination at patient's choice.

RESULTS

173 patients were included in this study, 124 in the StroVac group, 49 chose Nitrofuratoin. In the first 12 months, 86.8% of patients in the StroVac group and 91.8% in Nitrofurantoin group were successful (p = 0.22). Side effects were noted in 2.3% in the StroVac group causing discontinuation of therapy, whereas in the Nitrofurantoin group 18.4% stopped medication premature, mostly due to mild diarrhoea. In the second year 79.3% of patients in the StroVac group were still successful, most of them had undergone booster injection. In contrast, in the Nitrofurantoin group only 59.2% of patients were still successful (p = 0.03).

CONCLUSION

StroVac is an effective and lasting non-antibiotic prophylaxis for rUTI, easy to administer with low rates of adverse events and should be offered to patients with rUTI.

Risk analysis of antimicrobial resistance in outpatient urinary tract infections of young healthy adults

Objectives

Most studies addressing community-acquired urinary tract infections (UTIs) pertain to mixed cohorts, in which young healthy adults are under-represented. We aimed to dissect the intricate interrelation between exposures and subsequent antimicrobial resistance (AMR) patterns in a unique setting of young healthy adults, allowing further guidance in this group.

Methods

We carried out a retrospective cross-sectional study of all Enterobacteriaceae-associated outpatient UTIs during 2014-16 in soldiers, representing the young fit population in Israel. Electronic medical records were reviewed for demographic and clinical data, antimicrobial exposures and prescriptions. Risk factors for AMR were analysed by multivariate logistic regression.

Results

Of 1207 cases, 1144 (94.8%) were females, with a median age of 20.2 years. Escherichia coli was the predominant species (83.2%). Only 686 (56.8%) isolates were fully susceptible. AMR rates were as follows: trimethoprim/sulfamethoxazole, 19.6%; oral cephalosporins, 9.7%-16.7%; amoxicillin/clavulanate, 12.1%; ciprofloxacin, 11.1%; and nitrofurantoin, 12.6%. Predictors of AMR were recurrent UTIs, past-year hospitalization, male gender and non E. coli strains. Antimicrobials prescribed >6 months preceding the culprit infection were not related to AMR. Fluoroquinolone and cephalosporin exposures were highly predictive of further AMR, yet nitrofurantoin and, to a lesser extent, amoxicillin/clavulanate had fewer associations with AMR induction and resistance to these antimicrobials was less associated with any exposure.

Conclusions

This nationwide study of community-related UTIs shows significant AMR rates for commonly used oral antimicrobials even in young fit adults. Nitrofurantoin proved once more to be an adequate empirical choice regardless of previous exposures, having a less detrimental effect on future AMR. Conversely, both resistance to fluoroquinolones following previous exposures and the associated heavy ecological burden should deter their common use as first-line agents for UTIs.

Epidemiology and genotypic characterisation of dissemination patterns of uropathogenic Escherichia coli in a community

To characterise the dissemination patterns of uropathogenic Escherichia coli (UPEC) in a community, we conducted a study utilising molecular and fundamental descriptive epidemiology. The subjects, consisted of women having community-acquired acute urinary tract infection (UTI), were enrolled in the study from 2011 to 2012. UPEC isolates were subjected to antibacterial-susceptibility testing, O serogrouping, phylotyping, multilocus-sequence typing with phylogenetic-tree analysis and pulsed-field-gel electrophoresis (PFGE). From the 209 unique positive urinary samples 166 UPEC were isolated, of which 129 were fully susceptible to the tested antibiotics. Of the 53 sequence types (STs), the four most prevalent STs (ST95, ST131, ST73 and ST357) accounted for 60% of all UPEC strains. Antimicrobial resistance was less frequently observed for ST95 and ST73 than for the others. A majority of rare STs and a few common STs constituted the diversity pattern within the population structure, which was composed of the two phylogenetically distinct clades. Eleven genetically closely related groups were determined by PFGE, which accounted for 42 of the 166 UPEC isolates, without overt geo-temporal clustering. Our results indicate that a few major lineages of UPEC, selected by unidentified factors, are disseminated in this community and contribute to a large fraction of acute UTIs.

A new point-of-care test for the rapid detection of urinary tract infections

Urinary tract infections (UTIs) are among the most common infections in all age groups. Fast and accurate diagnosis is essential to ensure a timely and effective therapy. Alongside with reference culture-based methods, several point-of-care tests (POCTs) for early detection of UTIs have been developed, but they have not been significantly implemented in current clinical practice. The Micro Biological Survey (MBS) POCT is a simple test developed by MBS Diagnostics Ltd. (London, UK) for the detection and management of UTIs. The present study has been undertaken to investigate the potentials and limits of the MBS POCT. A total of 349 patients were enrolled in two open-label, monocentric, non-interventional clinical trials in collaboration with an Emergency Medicine department and the outpatient clinic of two hospitals in Rome. Results of urine analysis using the MBS POCT were compared with those of the routine culture-based tests for UTI diagnosis performed by the hospital laboratory. The MBS POCT provided fast results revealing high bacterial count UTIs (≥ 105 CFU/ml) with 97% accuracy, 92% sensitivity, 100% specificity, 99% PPV, and 96% NPV within a 5-h analytical time threshold.

Prevalence of Escherichia Coli and Its Antimicrobial Susceptibility Profiles among Patients with UTI at Mulago Hospital, Kampala, Uganda

Background

Urinary tract infections (UTIs) remain the most common infections diagnosed in in- and outpatients as well as hospitalized patients. Current knowledge on antimicrobial susceptibility pattern for uropathogens is essential to effectively manage UTIs. This study aimed at determining the prevalence of E. coli and its antimicrobial susceptibility profiles among patients presenting with signs and symptoms of UTI in Mulago Hospital in Uganda.

Methods

Midstream urine samples were collected from 100 patients presenting with signs and symptoms of UTI at the outpatient department of Mulago Hospital. The samples were cultured, and isolates of E. coli and its antimicrobial susceptibility profiles among patients presenting with signs and symptoms of UTI in Mulago Hospital in Uganda.

Results

Out of 100 patients studied, E. coli and its antimicrobial susceptibility profiles among patients presenting with signs and symptoms of UTI in Mulago Hospital in Uganda. Escherichia coli isolates were highly susceptible to cefotaxime/clavulanic acid (100%) and nitrofurantoin (70%) but showed high resistance to cefuroxime (100%), ceftazidime (100%), nalidixic acid (90%), and ciprofloxacin (90%).

Conclusion

Escherichia coli, the predominant uropathogen, showed significant multidrug resistance to antibiotics commonly prescribed for the management of UTIs. These findings should form a basis for preliminary decision making on the appropriate line of treatment for UTIs.Escherichia coli isolates were highly susceptible to cefotaxime/clavulanic acid (100%) and nitrofurantoin (70%) but showed high resistance to cefuroxime (100%), ceftazidime (100%), nalidixic acid (90%), and ciprofloxacin (90%).

Antimicrobial susceptibility among urinary Escherichia coli isolates from female outpatients: age-related differences

OBJECTIVES

Urinary tract infections (UTIs) are common problems in women, and important reason for visiting primary care physicians, resulting in substantial financial burden to community. The aim of this study was to determine the resistance rates of E. coli to commonly prescribed antimicrobial drugs for community-acquired UTIs in women and to establish the association between age and resistance to antibiotics among isolates of E. coli from urine.

METHODS

The study was designed as a retrospective cross-sectional study during the 5-years period. It was conducted on a sample of urinary tract isolates of E. coli taken from women with community-acquired UTIs. After prevalence of E. coli resistance to antibiotics was established, the analysis of risk factors for emergence of resistance was conducted.

RESULTS

There were 10,734 isolates of E. coli, comprising 70.62% of all samples analyzed. E. coli was the most frequently resistant to ampicillin (54.68%), followed by trimethoprim-sulphamethoxazole (37.46%), first and second generation cephalosporins (cephalexin and cefaclor) (29.53% both), and ciprofloxacin (23.80%). Less than 50% of E. coli isolates was sensitive to all three tested antibiotics, and nearly 13% acquired triple-resistance. Prevalence of isolates resistant to two or three agents was higher in the subgroup of women older than 65 years.

CONCLUSIONS

Empirical choice of antimicrobial agent for community-acquired non-complicated UTIs in women should be individualized on the basis of the patient's age, prevalence of resistance in the local community, and compliance history of the patient.

Joint Modeling of Resistance to Six Antimicrobials in Urinary Escherichia coli Isolates in Quebec, Canada

Empirical treatment of urinary tract infections should be based on susceptibility profiles specific to the locale and patient population. Additionally, these susceptibility profiles should account for correlations between resistance to different types of antimicrobials.

Empirical treatment of urinary tract infections should be based on susceptibility profiles specific to the locale and patient population. Additionally, these susceptibility profiles should account for correlations between resistance to different types of antimicrobials. We used hierarchical logistic regression models to investigate geographic, temporal, and demographic trends in resistance to six antimicrobials in community-acquired and nosocomial urinary E. coli isolates from three communities in the province of Quebec, Canada, procured between April 2010 and December 2017. A total of 74,986 community-acquired (patient age, ≥18 years) and 4,384 nosocomial isolates (patient age, ≥65 years) were analyzed. In both community-acquired and nosocomial isolates, we found geographic variation in the prevalence of resistance. Male sex (community-acquired hierarchical mean odds ratio [OR], 1.24; 95% credible interval [CI], 1.02 to 1.50; nosocomial hierarchical mean OR, 1.16, 95% CI, 0.92 to 1.41) and recent hospitalization (community-acquired hierarchical mean OR, 1.49; 95% CI, 1.33 to 1.66; nosocomial hierarchical mean OR, 1.31; 95% CI, 0.99 to 1.78) were associated with a higher risk of resistance to most types of antimicrobials. We found distinct seasonal trends in both community-acquired and nosocomial isolates, but only community-acquired isolates showed a consistent annual pattern. Ciprofloxacin resistance increased sharply with patient age. We found clinically relevant differences in antimicrobial resistance in urinary E. coli isolates between locales and patient populations in the province of Quebec. These results could help inform empirical treatment decisions for urinary tract infections. In the future, similar models integrating local, provincial, and national resistance data could be incorporated into decision support systems for clinicians.

Cost-effectiveness analysis of ceftazidime/avibactam compared to imipenem as empirical treatment for complicated urinary tract infections

Ceftazidime/avibactam (CAZ-AVI) is a novel, fixed-dose combination antibiotic that has been approved in Europe and the United States for patients with complicated urinary tract infections (cUTIs) based on results of a Phase III, randomized, comparative study (RECAPTURE study). The present analysis evaluated cost-effectiveness of CAZ-AVI as an empirical treatment for hospitalized patients with cUTIs from the Italian publicly funded healthcare (third-party payer) perspective. A sequential, patient-level simulation model was developed that followed the clinical course of cUTI and generated 5000 pairs of identical patients (CAZ-AVI or imipenem as empirical treatment). The model included additional impact of resistant pathogens; patients who did not respond to empirical treatment were switched to second-line treatment of colistin+high dose carbapenem in both groups. The time horizon of the model was five years, with an annual discount rate of 3% applied to both costs and quality-adjusted life-years (QALYs). The analysis demonstrated that an intervention sequence (CAZ-AVI followed by colistin+high dose carbapenem) compared with a comparator sequence (imipenem followed by colistin+high dose carbapenem) was associated with a net incremental cost of €1015 per patient but provided better health outcomes in terms of clinical cure (97.65% vs. 91.08%; ∆ = 6.57%), shorter hospital stays (10.65 vs. 12.55 days; ∆ = 1.90 days), and QALYs gained per patient (4.190 vs. 4.063; ∆ = 0.126). The incremental cost-effectiveness ratio was €8039/QALY, which is well below the willingness-to-pay threshold of €30 000/QALY in Italy. The results showed that CAZ-AVI is expected to be a cost-effective treatment compared with imipenem for cUTI in Italy.

Virulence targeted inhibitory effect of linalool against the exclusive uropathogen Proteus mirabilis

Proteus mirabilis is one of the leading causes of catheter-associated UTIs (CAUTI) in individuals with prolonged urinary catheterization. Since, biofilm assisted antibiotic resistance is reported to complicate the treatment strategies of P. mirabilis infections, the present study was aimed to attenuate biofilm and virulence factor production in P. mirabilis. Linalool is a naturally occurring monoterpene alcohol found in a wide range of flowers and spice plants and has many biological applications. In this study, linalool exhibited concentration dependent anti-biofilm activity against crystalline biofilm of P. mirabilis through reduced production of the virulence enzyme urease that raises the urinary pH and drives the formation of crystals (struvite) in the biofilm. The results of q-PCR analysis unveiled the down regulation of biofilm/virulence associated genes upon linalool treatment, which was in correspondence with the in vitro bioassays. Thus, this study reports the feasibility of linalool acting as a promising anti-biofilm agent against P. mirabilis mediated CAUTI.

Association between urinary community-acquired fluoroquinolone-resistant Escherichia coli and neighbourhood antibiotic consumption: a population-based case-control study

BACKGROUND

It is unknown whether increased use of antibiotics in a community increases the risk of acquiring antibiotic resistance by individuals living in that community, regardless of prior individual antibiotic consumption and other risk factors for antibiotic resistance.

METHODS

We used a hierarchical multivariate logistic regression approach to evaluate the association between neighbourhood fluoroquinolone consumption and individual risk of colonisation or infection of the urinary tract with fluoroquinolone-resistant Escherichia coli. We did a population-based case-control study of adults (aged ≥22 years) living in 1733 predefined geographical statistical areas (neighbourhoods) in Israel. A multilevel study design was used to analyse data derived from electronic medical records of patients enrolled in the Clalit state-mandated health service.

FINDINGS

300 105 events with E coli growth and 1 899 168 cultures with no growth were identified from medical records and included in the analysis. 45 427 (16·8%) of 270 190 women and 8835 (29·5%) of 29 915 men had fluoroquinolone-resistant E coli events. We found an independent association between residence in a neighbourhood with higher antibiotic consumption and an increased risk of bacteriuria caused by fluoroquinolone-resistant E coli. Odds ratios (ORs) for the quintiles with higher neighbourhood consumption (compared with the lowest quintile) were 1·15 (95% CI 1·06-1·24), 1·31 (1·20-1·43), 1·41 (1·29-1·54), and 1·51 (1·38-1·65) for women, and 1·17 (1·02-1·35), 1·24 (1·06-1·45), 1·35 (1·15-1·59), and 1·50 (1·26-1·77) for men. Results remained significant when the analysis was restricted to patients who had not consumed fluoroquinolones themselves.

INTERPRETATION

These data suggest that increased use of antibiotics in specific geographical areas is associated with an increased personal risk of acquiring antibiotic-resistant bacteria, independent of personal history of antibiotic consumption and other known risk factors for antimicrobial resistance.

FUNDING

None.

Non-extractable polyphenols from cranberries: potential anti-inflammation and anti-colon-cancer agents

Both extractable and non-extractable polyphenol (NEP) rich fractions from cranberries were bioactive and the NEP-rich fraction showed promising anti-inflammation and anti-colon cancer potential.

An evaluation of community-acquired urinary tract infection and appropriateness of treatment in an emergency department in Saudi Arabia

Introduction

Urinary tract infection (UTI) is a serious health problem affecting millions of people every year. Inappropriate antibiotic prescriptions put patients at risk and lead to bacterial resistance and elevated costs.

Aims

Study aims were to assess the prevalence and antibiotic-treatment patterns of community acquired UTIs, prevalence and types of antibiotic-prescribing errors, and the cost of inappropriate antibiotic use.

Methods

This was a retrospective cross-sectional study conducted over a 3-month period in an emergency department in Saudi Arabia.

Results

During the study period, 1,449 patients were diagnosed with UTIs, including pediatric (18.6%), adult (59.2%), and elderly (22.2%) patients. The overall prevalence of UTIs was 9.9% of total visits. Broad-spectrum antibiotics were prescribed for 85% of patients. Three main antibiotics were prescribed: cephalosporin (39%), penicillin (26%), and fluoroquinolone (22%). The overall prevalence of inappropriate antibiotic prescription with at least one type of error was 46.2% (pediatrics 51%, adults 46%, elderly 47%). Errors were dose (37%), duration (11%), frequency (6%), and antibiotic selection (2.4%). Dose error was significantly greater in pediatric patients (P=0.001). Duration error was higher among adults and the elderly (P=0.014). Significantly more inappropriate cephalosporin prescriptions were seen in adults (P=0.001), while penicillin had significantly higher errors in pediatric patients. Positive urine culture was seen in 34.9% of patients, and the most common microorganism was Escherichia coli (51%). The mean cost of care for one episode of UTI was US$134.56±$31.34 (95% CI $132.94-$136.17). Treatment of UTI was more costly in women (63.9% of total cost), adults (59.2%), and those using broad-spectrum antibiotics (86.5%). There were statistically significant associations among sex, age, spectrum of antibiotic, category of antibiotic, and inappropriate cost.

Conclusion

The results revealed a significant level of inappropriate use of antibiotics in the treatment of UTIs in the emergency department.

Antimicrobial Resistance Profile of mcr-1 Positive Clinical Isolates of Escherichia coli in China From 2013 to 2016

Multidrug-resistant (MDR) Escherichia coli poses a great challenge for public health in recent decades. Polymyxins have been reconsidered as a valuable therapeutic option for the treatment of infections caused by MDR E. coli. A plasmid-encoded colistin resistance gene mcr-1 encoding phosphoethanolamine transferase has been recently described in Enterobacteriaceae. In this study, a total of 123 E. coli isolates obtained from patients with diarrheal diseases in China were used for the genetic analysis of colistin resistance in clinical isolates. Antimicrobial resistance profile of polymyxin B (PB) and 11 commonly used antimicrobial agents were determined. Among the 123 E. coli isolates, 9 isolates (7.3%) were resistant to PB and PCR screening showed that seven (5.7%) isolates carried the mcr-1 gene. A hybrid sequencing analysis using single-molecule, real-time (SMRT) sequencing and Illumina sequencing was then performed to resolve the genomes of the seven mcr-1 positive isolates. These seven isolates harbored multiple plasmids and are MDR, with six isolates carrying one mcr-1 positive plasmid and one isolate (14EC033) carrying two mcr-1 positive plasmids. These eight mcr-1 positive plasmids belonged to the IncX4, IncI2, and IncP1 types. In addition, the mcr-1 gene was the solo antibiotic resistance gene identified in the mcr-1 positive plasmids, while the rest of the antibiotic resistance genes were mostly clustered into one or two plasmids. Interestingly, one mcr-1 positive isolate (14EC047) was susceptible to PB, and we showed that the activity of MCR-1-mediated colistin resistance was not phenotypically expressed in 14EC047 host strain. Furthermore, three isolates exhibited resistance to PB but did not carry previously reported mcr-related genes. Multilocus sequence typing (MLST) showed that these mcr-1 positive E. coli isolates belonged to five different STs, and three isolates belonged to ST301 which carried multiple virulence factors related to diarrhea. Additionally, the mcr-1 positive isolates were all susceptible to imipenem (IMP), suggesting that IMP could be used to treat infection caused by mcr-1 positive E. coli isolates. Collectively, this study showed a high occurrence of mcr-1 positive plasmids in patients with diarrheal diseases of Guangzhou in China and the abolishment of the MCR-1 mediated colistin resistance in one E. coli isolate.

The Emergency Department Diagnosis and Management of Urinary Tract Infection

Urinary tract infection (UTI) is a common infection seen in the emergency department. The spectrum of UTI includes simple versus complicated infection and lower versus upper UTI. No one history or examination finding is definitive for diagnosis. Testing often includes urinalysis and/or urine dipstick, and several pitfalls may occur in interpretation. Urine cultures should be obtained in complicated or upper UTIs but not simple and lower tract UTIs, unless a patient is pregnant. Imaging often is not required. Most patients with simple cystitis and pyelonephritis are treated as outpatients. A variety of potentially dangerous conditions may mimic UTI and pyelonephritis.

Lack of uniformity among United States recommendations for diagnosis and management of acute, uncomplicated cystitis

INTRODUCTION AND HYPOTHESIS

Acute, uncomplicated cystitis is one of the most common bacterial infections seen in clinical practice. Quality improvement and antibiotic stewardship efforts to optimize cystitis management rely on clinicians managing patients in a manner recommended by experts and guidelines. However, it is unclear if recent recommendations for cystitis from experts and guidelines from US medical societies that provide recommendations are well aligned.

METHODS

We examined recommendations and guidelines for acute, symptomatic cystitis in women published in US medical societies' journals from January 1, 2008, to December 31, 2016, within the fields of family medicine, obstetrics and gynecology, internal medicine, female pelvic medicine and reconstructive surgery, and infectious diseases.

RESULTS

All recommendations endorsed the use of symptoms and urine dipstick to diagnose cystitis. Some societies did not recommend urine dipstick in patients with recurrent urinary tract infection (UTI), classic UTI symptoms, or a lack of underlying conditions or competing diagnoses. All endorsed nitrofurantoin, trimethoprim-sulfamethoxazole, and fosfomycin as first-line agents. Some guidelines classified fluoroquinolones as second- or third-line, while others considered them first-line treatment for UTI. Avoiding use of amoxicillin and ampicillin, antibiotic agents with high prevalence of resistance in the US, was recommended by some societies.

CONCLUSIONS

US recommendations differed in their approach to the treatment of acute, uncomplicated cystitis. Lack of uniformity likely contributes to clinical management variance for patients with UTI and hampers quality improvement and antibiotic stewardship efforts aimed at promoting optimal management. Our findings emphasize the need for more consistent recommendations for cystitis management.

Early Clinical Assessment of the Antimicrobial Activity of Finafloxacin Compared to Ciprofloxacin in Subsets of Microbiologically Characterized Isolates

Two phase II studies were performed with patients with uncomplicated urinary tract infections (uUTIs) and complicated urinary tract infections (cUTIs) or acute pyelonephritis (PN) to compare finafloxacin (300 mg twice a day [b.i.d.] orally for uUTI and 800 mg once a day [q.d.] intravenously [i.v.] for cUTI/PN) and ciprofloxacin (250 mg b.i.d. orally for uUTI and 400 mg b.i.d. i.v. for cUTI/PN). The early response to the study medications was evaluated in the microbiological intent-to-treat population (mITT) at day 3. A total of 21% of the isolates were ciprofloxacin resistant, 13.7% were primed pathogens carrying a mutation(s) potentially fostering fluoroquinolone resistance development, and 7.1% produced extended-spectrum β-lactamases (ESBLs). Finafloxacin demonstrated very good early clinical activity, with microbiological eradication rates of 88.6% (n = 132), compared to 78.7% (n = 61) for ciprofloxacin, and 69.6% (n = 23), compared to 35.7% (n = 14) for ciprofloxacin, in patients with ciprofloxacin-resistant uropathogens; 94.1% (n = 17), compared to 80.0% (n = 10) for ciprofloxacin, in patients infected with uropathogens primed for fluoroquinolone resistance uropathogens; and 91.7% (n = 11), compared to 0% for ciprofloxacin, in patients infected with ESBL producers. Finafloxacin demonstrated early and rapid activity against uropathogens, including fluoroquinolone-resistant and/or multiresistant pathogens or ESBL producers, while ciprofloxacin was less active against this subset of resistant pathogens. Susceptibilities of pathogens were quantitated by broth microdilution. Isolates were subgrouped according to their susceptibility patterns, in particular first-step quinolone resistance, quinolone resistance, and ESBL production. Eradication was defined as the elimination or reduction of study entry pathogens to <10³ CFU/ml in urine culture. (The studies described in this paper have been registered at ClinicalTrials.gov under identifiers NCT00722735 and NCT01928433.).

Nanodiamonds facilitate killing of intracellular uropathogenic E. coli in an in vitro model of urinary tract infection pathogenesis

About 25–44% of women will experience at least one episode of recurrent UTI and the causative agent in over 70% of UTI cases is uropathogenic Escherichia coli (UPEC). UPEC cause recurrent UTI by evading the bladder’s innate immune system through internalization into the bladder epithelium where antibiotics cannot reach or be effective. Thus, it is important to develop novel therapeutics to eliminate these intracellular pathogens. Nanodiamonds (NDs) are biocompatible nanomaterials that serve as promising candidates for targeted therapeutic applications. The objective of the current study was to investigate if 6 or 25 nm NDs can kill extracellular and intracellular UPEC in infected bladder cells. We utilized the human bladder epithelial cell line, T24, and an invasive strain of UPEC that causes recurrent UTI. We found that acid-purified 6 nm NDs displayed greater antibacterial properties towards UPEC than 25 nm NDs (11.5% vs 94.2% CFU/mL at 100 μg/mL of 6 and 25 nm, respectively; P<0.001). Furthermore, 6 nm NDs were better than 25 nm NDs in reducing the number of UPEC internalized in T24 bladder cells (46.1% vs 81.1% CFU/mL at 100 μg/mL of 6 and 25 nm, respectively; P<0.01). Our studies demonstrate that 6 nm NDs interacted with T24 bladder cells in a dose-dependent manner and were internalized in 2 hours through an actin-dependent mechanism. Finally, internalization of NDs was required for reducing the number of intracellular UPEC in T24 bladder cells. These findings suggest that 6 nm NDs are promising candidates to treat recurrent UTIs.

Impact of Allergy and Resistance on Antibiotic Selection for Recurrent Urinary Tract Infections in Older Women

OBJECTIVES

To review the impact of antibiotic allergy and resistance in older women with recurrent urinary tract infections (RUTIs) as determinants for a suitable oral antibiotic treatment choice.

METHODS

A prospectively maintained database of women 65 years old and older with documented RUTIs (≥3 UTI/y) and trigonitis on cystoscopy was reviewed. Demographic data, known drug allergies, renal function, antibiotic susceptibility of most recent urine culture, allergy, or resistance to trimethoprim-sulfamethoxazole (TMP-SMX), fluoroquinolones, and nitrofurantoin were obtained.

RESULTS

From 2006 to 2014, 86 women with RUTIs met study criteria. Mean age was 77.9 ± 7.8, with 94% being Caucasian. An estimated glomerular filtration rate >30 mL/min was noted in 94%. The percentage of women allergic, resistant, or both allergic and resistant to TMP-SMX was 33%, 29%, and 15%, to fluoroquinolones was 14%, 34%, and 8.1%, or nitrofurantoin was 16%, 14%, and 5%, respectively. Twenty-eight percent (24 of 86) of women who were allergic and/or resistant to TMP-SMX and fluoroquinolones were sensitive to nitrofurantoin. Twenty percent (17 of 86) were allergic and/or resistant to all 3 antibiotics. Women who were allergic or resistant to TMP-SMX had a significantly higher number of other antibiotic resistances compared with women sensitive to TMP-SMX (4.9 ± 3.6 vs 2.1 ± 2.3; P < .0001). Similarly, women with fluoroquinolone allergy or resistance had significantly more antibiotic resistances than those who were fluoroquinolone sensitive (5.8 ± 3.5 vs 2.3 ± 2.5; P < .0001).

CONCLUSION

Because of allergy and/or antibiotic resistance, several first-line antibiotics are not available for many older women with RUTIs. In nearly a third of women, nitrofurantoin was the only viable alternative.

Bacteriological profile and antimicrobial susceptibility patterns of urine culture isolates from patients in Ndjamena, Chad

Introduction

Bacteriological profile and antimicrobial susceptibility patterns of urine culture isolates were determined among patients in the Ndjamena General Hospital, a National Reference centre.

Methods

A cross-sectional study was carried out from July to November 2014. Six hundred and sixty patients were enrolled, to whom a cytobacteriological examination of urine was prescribed. Urine was collected and cultured. Bacterial identification and antimicrobial susceptibility patterns were performed using Vitek 2 compact automated system.

Results

216 isolates were recovered from patients (age range: 10-90 years). E. coli was the pathogen frequently cultured 128 (59.3%) followed by K. pneumonia 28 (13.0%). Bacteriuria was more present in inpatients (70.4%) compared to outpatients (29.6%). High antibiotic-resistance rate (> 60%) of the total isolates was observed with ampicillin, ciprofloxacin and cephalosporins. Imipeneme (94.9%) displayed satisfactory activity against bacteria isolates. ESBLs phenotype was present in 68/105 (64.7%) of betalactamine resistant isolates. AAC(3)-I and AAC(6’)-I enzymes were found respectively in 16/36 (44.4%) and 20/36 (55.6%) of aminoglycosides resistant isolates. Resistance of isolates to quinolones was mainly due to an association of target modification (gyrA and parC), porin reduction and/or efflux mechanisms and was present in 107/213 (49%) of quinolones resistant isolates.

Conclusion

E. coli is the predominant uropathogen isolated in our setting and there are antibiotic-resistant uropathogens among the studied population. Therefore, routine surveillance of bacterial uropathogens to common used antibiotics must be a continuous process so as to provide physicians with up to date information about the local data of antimicrobial resistance.

Elevated antibiotic resistance of Sudanese urinary tract infection bacteria

This study determined the prevalence of urinary tract infections in the Sudanese state of Khartoum and antimicrobial susceptibility pattern of isolated bacterial species. 200 adult patient urine specimens were collected and cultivated to identify the growing bacteria and their susceptibility to antibiotics. 35 % of specimens had significant bacterial growth. The most frequent isolates in this study were E. coli, E. faecalis and S. aureus. Most of the isolates were resistant to many antibiotics; Gram-negative and Gram-positive isolates were resistant to 67 % and 44 % of the examined antibiotics, respectively. E. coli was the most frequent bacterium in the studied samples and it was highly resistant to first-line antibiotics. The most resistant bacteria isolated were Pseudomonas species and the lowest was for S. saprophyticus. The results highlighted the need for knowledge about antibiotic susceptibility profile of the bacteria causing UTI prior to antibiotic prescription in order to ensure optimal treatment.

A new concept and a comprehensive evaluation of SYSMEX UF-1000i flow cytometer to identify culture-negative urine specimens in patients with UTI

Urinary tract infections (UTIs) are among the most common bacterial infections in men and urine culture is gold standard for diagnosis. Considering the high prevalence of culture-negative specimens, any method that identifies such specimens is of interest. The aim was to evaluate a new screening concept for flow cytometry analysis (FCA). The outcomes were evaluated against urine culture, uropathogen species and three conventional screening methods. A prospective, consecutive study examined 1,312 urine specimens, collected during January and February 2012. The specimens were analyzed using the Sysmex UF1000i FCA. Based on the FCA data culture negative specimens were identified in a new model by use of linear discriminant analysis (FCA-LDA). In total 1,312 patients were included. In- and outpatients represented 19.6% and 79.4%, respectively; 68.3% of the specimens originated from women. Of the 610 culture-positive specimens, Escherichia coli represented 64%, enterococci 8% and Klebsiella spp. 7%. Screening with FCA-LDA at 95% sensitivity identified 42% (552/1312) as culture negative specimens when UTI was defined according to European guidelines. The proposed screening method was either superior or similar in comparison to the three conventional screening methods. In conclusion, the proposed/suggested and new FCA-LDA screening method was superior or similar to three conventional screening methods. We recommend the proposed screening method to be used in clinic to exclude culture negative specimens, to reduce workload, costs and the turnaround time. In addition, the FCA data may add information that enhance handling and support diagnosis of patients with suspected UTI pending urine culture.

Immunity to uropathogens: the emerging roles of inflammasomes

Urinary tract infections (UTIs) cause a huge burden of morbidity worldwide with recurrent UTIs becoming increasingly frequent owing to the emergence of antibiotic-resistant bacterial strains. Interactions between the innate and adaptive immune responses to pathogens colonizing the urinary tract have been the focus of much research. Inflammasomes are part of the innate immune defence and can respond rapidly to infectious insult. Assembly of the multiprotein inflammasome complex activates caspase-1, processes proinflammatory cytokines IL-1β and IL-18, and induces pyroptosis. These effector pathways, in turn, act at different levels to either prevent or resolve infection, or eliminate the infectious agent itself. In certain instances, inflammasome activation promotes tissue pathology; however, the precise functions of inflammasomes in UTIs remain unexplored. An improved understanding of inflammasomes could provide novel approaches for the design of diagnostics and therapeutics for complicated UTIs, enabling us to overcome the challenge of drug resistance.

Source Identification and Source Control

Identifying sources of infection and establishing source control is an essential component of the workup and treatment of sepsis. Investigation with history, physical examination, laboratory tests, and imaging can in identifying sources of infection. All organ systems have the potential to develop sources of infection. However, there are inherent difficulties presented by some that require additional diligence, namely, urinalysis, chest radiographs, and intraabdominal infections. Interventions include administration of antibiotics and may require surgical or other specialist intervention. This is highlighted by the Surviving Sepsis Campaign with specific recommendations for time to antibiotics and expeditious time to surgical source control.

Five-Year Antimicrobial Resistance Patterns of Urinary Escherichia coli at an Australian Tertiary Hospital: Time Series Analyses of Prevalence Data

This study describes the antimicrobial resistance temporal trends and seasonal variation of Escherichia coli (E. coli) urinary tract infections (UTIs) over five years, from 2009 to 2013, and compares prevalence of resistance in hospital- and community-acquired E. coli UTI. A cross sectional study of E. coli UTIs from patients attending a tertiary referral hospital in Canberra, Australia was undertaken. Time series analysis was performed to illustrate resistance trends. Only the first positive E. coli UTI per patient per year was included in the analysis. A total of 15,022 positive cultures from 8724 patients were identified. Results are based on 5333 first E. coli UTIs, from 4732 patients, of which 84.2% were community-acquired. Five-year hospital and community resistance rates were highest for ampicillin (41.9%) and trimethoprim (20.7%). Resistance was lowest for meropenem (0.0%), nitrofurantoin (2.7%), piperacillin-tazobactam (2.9%) and ciprofloxacin (6.5%). Resistance to amoxycillin-clavulanate, cefazolin, gentamicin and piperacillin-tazobactam were significantly higher in hospital- compared to community-acquired UTIs (9.3% versus 6.2%; 15.4% versus 9.7%; 5.2% versus 3.7% and 5.2% versus 2.5%, respectively). Trend analysis showed significant increases in resistance over five years for amoxycillin-clavulanate, trimethoprim, ciprofloxacin, nitrofurantoin, trimethoprim-sulphamethoxazole, cefazolin, ceftriaxone and gentamicin (P<0.05, for all) with seasonal pattern observed for trimethoprim resistance (augmented Dickey-Fuller statistic = 4.136; P = 0.006). An association between ciprofloxacin resistance, cefazolin resistance and ceftriaxone resistance with older age was noted. Given the relatively high resistance rates for ampicillin and trimethoprim, these antimicrobials should be reconsidered for empirical treatment of UTIs in this patient population. Our findings have important implications for UTI treatment based on setting of acquisition.

Virulence and antimicrobial resistance of common urinary bacteria from asymptomatic students of Niger Delta University, Amassoma, Bayelsa State, Nigeria

Background:

Asymptomatic bacteriuria frequently occurs among all ages with the possibility of developing into urinary tract infections, and the antimicrobial resistance patterns of the etiologic organisms are essential for appropriate therapy. Thus, we investigated the virulence and antimicrobial resistance patterns of common urinary bacteria in asymptomatic students of Niger Delta University, Amassoma, Bayelsa State, Nigeria in a cross-sectional study.

Materials and Methods:

Clean catch mid-stream early morning urine samples collected from 200 asymptomatic University students of aged ranges 15–30 years were cultured, screened and common bacteria were identified using standard microbiological procedures. The isolates were screened for hemolysin production and their susceptibility to antibiotics was determined using standard disc assay method.

Results:

A total prevalence rate of 52.0% significant bacteriuria was detected and it was significantly higher among the female with a weak association (χ² = 6.01, phi = 0.173, P = 0.014). The Klebsiella pneumoniae and Staphylococcus aureus isolates were most frequently encountered among the isolated bacteria and 18 (12.7%) of all the bacterial isolates produced hemolysins. All the bacterial isolates exhibited 50–100% resistance to the tested beta-lactam antibiotics, tetracycline and co-trimoxazole. The isolated bacteria were 85-100% multi-drug resistant. However, most of the isolates were generally susceptible to gentamicin and ofloxacin. The phenotypic detection of extended-spectrum beta-lactamases was 9 (9.6%) among the tested Gram-negative bacterial isolates.

Conclusions:

The observed high proportions of multidrug resistant urinary bacteria among asymptomatic University students call for the need of greater control of antibiotic use in this study area.

Prevalence of Urinary Tract Infection and Antimicrobial Susceptibility among Diabetic Patients with Controlled and Uncontrolled Glycemia in Kuwait

Diabetic patients have higher risk of urinary tract infection (UTI). In the present study, we investigated the impact of glycemic control in diabetic patients on UTI prevalence, type of strains, and their antimicrobial drugs susceptibility. This study was conducted on urine samples from 722 adult diabetic patients from which 252 (35%) samples were positive for uropathogens. Most UTI cases occurred in the uncontrolled glycemic group (197 patients) versus 55 patients with controlled glycemia. Higher glycemic levels were measured in uncontrolled glycemia group (HbA1c = 8.3 ± 1.5 and 5.4 ± 0.4, resp., P < 0.0001). Females showed much higher prevalence of UTI than males in both glycemic groups (88.5% and 11.5%, resp., P < 0.0001). In the uncontrolled glycemia group 90.9% of the UTI cases happened at ages above 40 years and a clear correlation was obtained between patient age ranges and number of UTI cases (r = 0.94; P = 0.017), whereas in the group with controlled glycemia no trend was observed. Escherichia coli was the predominant uropathogen followed by Klebsiella pneumoniae and they were together involved in 76.2% of UTI cases. Those species were similarly present in both diabetic groups and displayed comparable antibiotic resistance pattern. These results highlight the importance of controlling glycemia in diabetic patients to reduce the UTI regardless of age and gender.

Threading the Needle: Small-Molecule Targeting of a Xenobiotic Receptor to Ablate Escherichia coli Polysaccharide Capsule Expression Without Altering Antibiotic Resistance

BACKGROUND

Uropathogenic Escherichia coli (UPEC), a leading cause of urinary tract and invasive infections worldwide, is rapidly acquiring multidrug resistance, hastening the need for selective new anti-infective agents. Here we demonstrate the molecular target of DU011, our previously discovered potent, nontoxic, small-molecule inhibitor of UPEC polysaccharide capsule biogenesis and virulence.

METHODS

Real-time polymerase chain reaction analysis and a target-overexpression drug-suppressor screen were used to localize the putative inhibitor target. A thermal shift assay quantified interactions between the target protein and the inhibitor, and a novel DNase protection assay measured chemical inhibition of protein-DNA interactions. Virulence of a regulatory target mutant was assessed in a murine sepsis model.

RESULTS

MprA, a MarR family transcriptional repressor, was identified as the putative target of the DU011 inhibitor. Thermal shift measurements indicated the formation of a stable DU011-MprA complex, and DU011 abrogated MprA binding to its DNA promoter site. Knockout of mprA had effects similar to that of DU011 treatment of wild-type bacteria: a loss of encapsulation and complete attenuation in a murine sepsis model, without any negative change in antibiotic resistance.

CONCLUSIONS

MprA regulates UPEC polysaccharide encapsulation, is essential for UPEC virulence, and can be targeted without inducing antibiotic resistance.

Prevalence of Class 1 Integrons and Extended Spectrum Beta Lactamases among Multi-Drug Resistant Escherichia coli Isolates from North of Iran

Background:

Extended spectrum beta lactamases (ESBLs) are an important cause of transferable multidrug resistance (MDR) in gram-negative bacteria. The most described ESBL genes are generally found within integron-like structures as mobile genetic elements. The aim of this study was to identify the accompanying of class 1 integrons and ESBLs in the MDR E. coli isolates.

Methods:

Susceptibility to antimicrobial agents was determined for 33 E. coli strains by the disk diffusion method. Double-disk synergy test was applied for screening ESBL. To identify the strains carrying integrons, the conserved regions of integron-encoded integrase gene intI1 were amplified. For detection of gene cassettes, 5′CS and 3′CS primers were used.

Results:

All E. coli isolates were identified as multi-drug resistant. More than 50% of the isolates were resistant to tetracycline, cephalothin, cefuroxime, amoxicillin-clavulanic acid, and third generation cephalosporines. Nearly all of the isolates displayed sensitivity to piperacillin. There was a significant correlation between production of ESBL and resistance to all antibiotics except for ciprofloxacin and piperacillin (P < 0.01). Thirty two MDR strains (97%) included class 1 integron, and some isolates that included integrons were similar in the size of gene cassettes. The isolates were different in the resistance profiles; however, some others had similar resistance profiles. Of eight ESBL positive isolates, seven (87.5%) carried class 1 integrons.

Conclusion:

Class 1 integrons were frequent in MDR and also ESBL-producing E. coli isolates. High prevalence of class 1 integrons confirms that integron-mediated antimicrobial gene cassettes are important in E. coli resistance profile.

Advanced glycation end products facilitate bacterial adherence in urinary tract infection in diabetic mice

Diabetic individuals have increased susceptibility to urinary tract infection (UTI), a common, painful condition. During diabetes mellitus, non-enzymatic reactions between reducing sugars and protein amine groups result in excessive production of advanced glycation end products (AGEs) that accumulate in tissues. Since bacteria adhere to cell surfaces by binding to carbohydrates, we hypothesized that adherence of bacteria to the bladder in diabetics may be enhanced by accumulation of AGEs on urothelial surface proteins. Using a murine model of UTI, we observed increased adherence of type 1 fimbriated uropathogenic Escherichia coli (UPEC) to the bladder in streptozotocin-induced diabetic female mice compared with age-matched controls, along with increased concentrations of two common AGEs in superficial urothelial cells from diabetic bladders. Several lectins with different specificities exhibited increased binding to urothelial homogenates from diabetic mice compared with controls, and two of those lectins also bound to AGEs. Furthermore, mannose-binding type 1 fimbriae isolated from UPEC bound to different AGEs, and UPEC adherence to the bladder in diabetic mice, were inhibited by pretreatment of mice with the AGE inhibitor pyridoxamine. These results strongly suggest a role for urothelial AGE accumulation in increased bacterial adherence during UTI in diabetes.

Establishment and Characterization of UTI and CAUTI in a Mouse Model

Urinary tract infections (UTI) are highly prevalent, a significant cause of morbidity and are increasingly resistant to treatment with antibiotics. Females are disproportionately afflicted by UTI: 50% of all women will have a UTI in their lifetime. Additionally, 20-40% of these women who have an initial UTI will suffer a recurrence with some suffering frequent recurrences with serious deterioration in the quality of life, pain and discomfort, disruption of daily activities, increased healthcare costs, and few treatment options other than long-term antibiotic prophylaxis. Uropathogenic Escherichia coli (UPEC) is the primary causative agent of community acquired UTI. Catheter-associated UTI (CAUTI) is the most common hospital acquired infection accounting for a million occurrences in the US annually and dramatic healthcare costs. While UPEC is also the primary cause of CAUTI, other causative agents are of increased significance including Enterococcus faecalis. Here we utilize two well-established mouse models that recapitulate many of the clinical characteristics of these human diseases. For UTI, a C3H/HeN model recapitulates many of the features of UPEC virulence observed in humans including host responses, IBC formation and filamentation. For CAUTI, a model using C57BL/6 mice, which retain catheter bladder implants, has been shown to be susceptible to E. faecalis bladder infection. These representative models are being used to gain striking new insights into the pathogenesis of UTI disease, which is leading to the development of novel therapeutics and management or prevention strategies.

Isolation and Molecular Detection of Gram Negative Bacteria Causing Urinary Tract Infection in Patients Referred to Shahrekord Hospitals, Iran

BACKGROUND

Urinary Tract Infections (UTI), and their complications, cause serious health problems, which affect millions of people every year. Infections of the urinary tract are the second most common type of infection in the body and approximately 20% of women are especially prone to UTIs for reasons not yet well understood. Urinary Tract Infections in men are not as common as in women yet can be very serious when they do occur. Accurate identification of bacterial isolates is an essential task of the clinical microbiology laboratory.

OBJECTIVES

The purpose of this study was to determine the incidence and variety of the causative microbial agents of UTIs in patients who had referred to a medical laboratory of Kashani and Hajar hospital in Shahrekord, Iran.

PATIENTS AND METHODS

In this cross-sectional study 147 urine samples of patients (urine test results were positive for UTIs) were examined during April to September 2013. A total of 147 urine samples of patients with clinical symptoms of UTI who had been referred to a medical laboratory of Kashani and Hajar hospital in Shahrekord (Iran), were collected and processed immediately for laboratory analysis.

RESULTS

Escherichia coli was identified as the most common causative agent of UTIs (51.70% of total isolates in both sexes), followed by Klebsiella pneumoniae (K. Pneumoniae) (16.32%). Frequency of Proteus spp., Acinetobacter spp., Entrobacter spp., Citrobacter spp., Pseudomonas aeruginosa (P. aeruginosa) and Providencia spp. was 10.88%, 6.12%, 5.44%, 4.08%, 3.40% and 2.04%, respectively. Statistical analysis by Fisher exact test showed that there was no significant relationship between the type of bacteria and gender (P > 0.05). Chi square test showed that there was no significant relationship between the type of bacteria and the use of catheter and age group (P > 0.05). However, there was a significant relationship between the type of bacteria and the history of hospitalization (P > 0.05).

CONCLUSIONS

Our findings implied that a wide range of bacteria could be involved in creating urinary tract infection in patients referred to a medical laboratory of Kashani and Hajar hospital in Shahrekord, Iran. Regardless of age, sex and the use of catheter, a wide range of bacteria could be involved in urinary tract infections.

Prevalence and risk factors for trimethoprim-sulfamethoxazole-resistant Escherichia coli among women with acute uncomplicated urinary tract infection in a developing country

BACKGROUND

Prospective studies from developing countries that have investigated risk factors for trimethoprim-sulfamethoxazole (TMP-SMX)-resistant Escherichia coli in women with uncomplicated urinary tract infection (UTI) remain scarce.

METHODS

Women with acute uncomplicated UTI were enrolled prospectively. Urine was sent for antimicrobial susceptibility testing. Logistic regression analysis was used to identify risk factors for TMP-SMX resistance.

RESULTS

Of 405 participants, 229 (56.5%) had bacteriuria (mean age 31.9 ± 9.5 years). In the previous 12 months, 77 (33.6%) had experienced at least one UTI episode and 106 (46.3%) reported antimicrobial use. The most common uropathogens were E. coli (75.8%) and Staphylococcus saprophyticus (8.9%). For the 179 E. coli, resistance rates were highest for ampicillin (64.3%) and TMP-SMX (41.3%). Resistance to cephalosporins, nitrofurantoin, and fluoroquinolones was much lower compared with the hospital laboratory-based surveillance data. Risk factors for TMP-SMX resistance were UTI in the last 6 months (odds ratio 2.22; p = 0.04) and the number of UTI episodes in the past year (odds ratio 2.06; p = 0.004). The number of UTI episodes (adjusted odds ratio 2.21; p = 0.02) remained significant on multivariate analysis.

CONCLUSIONS

TMP-SMX resistance was high. Number of previous UTI episodes was associated with increased risk of resistance; prior antimicrobial use was not. Hospital antibiograms should be used with caution when treating uncomplicated UTI.