Susceptibility patterns and ESBL rates of Escherichia coli from urinary tract infections in Canada and the United States, SMART 2010-2014

Antimicrobial-Resistant Infections in Hospitalized Patients

Importance

Antimicrobial resistance is a major public health problem in the US. Estimating national rates of antimicrobial-resistant infections commonly associated with health care can aid in targeted public health efforts.

Objective

To determine the national incidence rates of 6 pathogens over time: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus spp (VRE), extended-spectrum cephalosporin-resistant Escherichia coli and Klebsiella spp (excluding Klebsiella aerogenes) (ESCR-EK), carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant Acinetobacter spp (CRAsp), and multidrug-resistant (MDR) Pseudomonas aeruginosa.

Design, Setting, and Participants

This cohort study used data from 2012 to 2022 on inpatient hospitalizations, clinical cultures, and facility-level characteristics. Hospital-months were included in the dynamic cohort if the hospital reported at least 1 culture with microbial growth accompanied by antimicrobial susceptibility testing (AST) results in the month. Data from the PINC-AI and Becton Dickinson Insights databases were used, and cases were defined as incident nonsurveillance cultures yielding an organism of interest with sufficient AST results for a phenotype of interest. Data were collected from January 2012 to December 2022 and analyzed from April 2023 to June 2024.

Exposure

Inpatient hospitalizations with a discharge date in an included hospital month.

Main Outcomes and Measures

National annual antimicrobial-resistant cases per 10 000 hospitalizations were obtained using weights based on facility-level characteristics. Cases were defined as community-onset if collected on or before day 3 of hospitalization and hospital-onset if obtained on day 4 or later.

Results

This study cohort included 332 to 606 hospitals per year between 2012 to 2022 and 7 158 139 cultures. Antimicrobial-resistant pathogens accounted for an estimated 569 749 (95% CI, 475 949-663 548) cases and 179.6 (95% CI, 163.1-196.1) cases per 10 000 hospitalizations in 2022. Of these cases, 77% (437 657; 95% CI, 364 529-510 785) were community-onset and 23% (132 092; 95% CI, 108 241-155 943) were hospital-onset. MRSA (44% [251 854; 95% CI, 209 558-294 150]) and ESCR-EK (35% [200 884; 95% CI, 163 692-238 077]) made up the largest proportions of total infections in 2022, respectively. Rates of hospital-onset MRSA, VRE, CRE, CRAsp, and MDR P aeruginosa had periods of decline from 2012 to 2019; however, all pathogens experienced an increase in hospital-onset rates in 2020 and 2021. Community-onset ESCR-EK rates increased from 2012 to 2022, while community-onset rates of MRSA, VRE, and MDR P aeruginosa declined.

Conclusions and Relevance

While antimicrobial resistance rates have experienced uneven declines in the US from 2012 to 2022, the burden of resistance remains substantial. These findings suggest that more effective strategies to reduce antimicrobial resistance are needed.

Antimicrobial resistance in Escherichia coli and Staphylococcus aureus at human-animal interfaces on Chongming Island, Shanghai: A One Health perspective

Antimicrobial resistance (AMR) is a significant concern within the One Health framework due to its ability to spread across multiple interfaces. Phenotypic data remains the primary type for AMR surveillance, but exploring association across multiple interfaces poses certain challenges. In this study, AMR phenotypic data of clinical and food animal E. coli and S. aureus from Chongming Island over the past five years were analyzed to determine key characteristics of AMR and explore its association at the human-animal interface. The clinical E. coli isolates showed significant resistance to penicillins (83.92 %), cephems (63.05 %), fluoroquinolones (62.21 %), and tetracyclines (57.77 %), while S. aureus exhibited high resistance to penicillinase-labile penicillins (90.89 %), macrolides (51.51 %), penicillinase-stable penicillins (43.96 %), and lincosamides (43.55 %). Extended-spectrum β-lactamase (ESBL)-producing E. coli isolates accounted for 53.26 % (1398/2526), while methicillin-resistant Staphylococcus aureus (MRSA) prevalence was 43.81 % (435/993). Notably, there has been an increase in the proportion of E. coli isolates resistant to 8 to 12 antimicrobial classes, and in the proportion of S. aureus isolates resistant to 5 to 9 classes. Certain multi-drug resistance (MDR) phenotypes were first identified in food animal isolates and later emerged in clinical settings. Meanwhile, several MDR phenotypes were shared between the two interfaces, with 44 identified in E. coli and 12 in S. aureus. Further co-occurrence analysis in E. coli and S. aureus identified several co-occurrence phenotypic pairs or clusters, potentially mediated by a single plasmid or multiple plasmids within a bacterium, indicating potential associations at the human-animal interface. To summarize, a heightened prevalence of MDR in clinical E. coli and S. aureus has been observed, with some MDR profiles appearing in food animals before emerging in clinical settings. The co-occurrence of phenotypic pairs or clusters underscores the potential for AMR association and transmission between humans and food animals. Within the One Health framework, integrating genomic data into AMR monitoring is a crucial next step.

Management of Bacteriuria and Urinary Tract Infections in the Older Adult

Urinary tract infection (UTI) is one of the most frequent bacterial infections diagnosed in older adults and the most common reason for antibiotic prescriptions in nursing homes. Distinguishing between asymptomatic bacteriuria and UTI in older adults can be challenging and implementing a systematic approach to diagnosis using standard toolkits or algorithms is recommended for patients residing in post-acute and long-term care settings. This article reviews the pathophysiology, microbiology, diagnostic approach, treatment, and approaches to prophylaxis in the older adult.

Prevalence, Risk Factors and Antibiotic Resistance of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in Children Hospitalized with Urinary Tract Infection at King Abdulaziz University Hospital, Jeddah, Saudi Arabia

BACKGROUND/OBJECTIVES

We aimed to assess the prevalence and risk factors for acquisition of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) in children admitted with urinary tract infection (UTI) at a tertiary university hospital in Saudi Arabia, as well as to investigate antibiotic resistance patterns.

METHODS

This retrospective cross-sectional study involved hospitalized children aged 0-14 years from January 2018 to December 2022 with urine cultures that grew E. coli or ESBL-producing E. coli. Data of the antimicrobial susceptibility for isolated bacteria were collected.

RESULTS

This study analyzed 242 urine samples obtained from 119 children with E. coli UTIs. Of these, 20.7% (n = 50) were ESBL producers. Previous antibiotic use (last 3 months), prophylactic antibiotic use, prior UTI (last 3 months), recurrent UTIs, and underlying co-morbidities (p = 0.011, <0.001, 0.025, <0.001, and 0.013, respectively) had a significant relationship with increased risk of ESBL E. coli UTIs. Generally, the highest resistance rates in the ESBL-producing isolates were for ampicillin and third-generation cephalosporin. Conversely, all ESBL-positive isolates were sensitive to meropenem, with variable resistance rates to other antibiotics as amikacin, nitrofurantoin, quinolones and trimethoprim/sulfamethoxazole (2%, 8%, 56% and 64%, respectively).

CONCLUSIONS

There is a high prevalence of ESBL production among children hospitalized with E. coli UTIs. Addressing ESBL UTI risk factors helps to recognize high-risk cases and enhance proper antibiotic use.

Prevalence and risk factors of antibiotic resistance for urinary tract infections in patients presenting to a Belgian tertiary care emergency department: testing the national guidelines against the local setting

OBJECTIVES

Urinary tract infections (UTIs) are an important cause of empiric antibiotic (over)treatment at the emergency department (ED). To enhance empiric antibiotic choices, mapping the national and local microbiology and antimicrobial resistance (AMR) patterns is crucial. This study aims to examine resistance patterns at a Brussels ED and to identify risk factors for AMR to evaluate current treatment guidelines and help combat AMR.

METHODS

Adult patients undergoing urinalysis at the ED of a Brussels tertiary care hospital with positive urine cultures were included. Descriptive microbiological mapping of UTI or asymptomatic bacteriuria (ASB) micro-organisms was performed. Potential risk factors of antibiotic resistance in Gram-negative bacteria were assessed by using logistic regression analysis.

RESULTS

Out of 96 patients with Gram-negative bacteria in urinary culture, the predominant uropathogen was Escherichia coli (58.3%), with 8.6% being extended spectrum beta-lactamase (ESBL)-producing strains. Overall, fosfomycin (29.2%) and nitrofurantoin (28.6%) showed the highest resistance rates. Ceftriaxone revealed lower resistance rates (13.1%) compared to ciprofloxacin (17.0%) and cefuroxime (18.4%). Temocillin exhibited the lowest resistance rate (8.2%) especially against ESBLs (0%). Ciprofloxacin resistance increased with age (OR 1.05 [1.01-1.10]) and recurrent UTIs (OR 4.79 [1.18-19.42]). Male gender was associated with higher odds of temocillin resistance (OR 5.79 [1.18-28.34]).

CONCLUSION

In the studied Belgian ED setting, ceftriaxone seems slightly safer than ciprofloxacin, especially for recurrent UTI patients. However, overall, and especially in patients at risk for ESBL-producing bacteria, temocillin would be an even better choice in our setting. National microbiological data should be reviewed to support recommending temocillin as a first-line antibiotic in patients presenting with upper UTI.

Extended-spectrum β-lactamase-producing Escherichia coli from poultry: A review

Extended-spectrum β-lactamases (ESBLs) are β-lactamase enzymes produced by Gram-negative bacterial pathogens that harbor the ESBL genes. In addition, most ESBL genes are plasmid-mediated and usually encode a broader spectrum of antimicrobial resistance, especially to penicillins, first-generation, second-generation, and third-generation cephalosporins, as well as monobactam, such as aztreonam. Escherichia coli has become an opportunistic pathogen, especially in poultry, and has been implicated in zoonotic diseases that can be transmitted to humans, resulting in public health problems. Poultry can act as carriers of ESBL-producing E. coli (ESBL-EC) bacteria to humans through poultry meat that is contaminated by waste products, feces, and excretions. The ESBL gene CTX-M type was identified as the main cause of infection in humans and was detected in poultry as a cause of infection accompanied by clinical symptoms. Several studies have also shown a link between E. coli and ESBL gene transfer from birds to humans. Controlling the spread of ESBL-EC involves maintaining the cleanliness of poultry products, especially meat, and eliminating contaminant sources from poultry. Likewise, maintaining the environmental cleanliness of poultry slaughterhouses and poultry farms must be taken as a precautionary measure to curtail the increasing spread of ESBL-EC into the environment. This review aimed to explain the spread of ESBL-producing E. coli in poultry.

Co-resistance Among Escherichia coli and Klebsiella pneumoniae Urine Isolates from Female Outpatients with Presumed UTI: A Retrospective US Cohort Study

INTRODUCTION

Urinary tract infections (UTIs) caused by antimicrobial-resistant Enterobacterales are a global health threat. There are limited surveillance data available to characterize the prevalence of antimicrobial resistance among outpatients in the United States (US).

METHODS

This retrospective cohort (database) study investigated co-resistance among Escherichia coli and Klebsiella pneumoniae urinary isolates from US female outpatients aged ≥ 12 years with presumed uncomplicated UTI (uUTI), ≥ 3 months of data (2011-2019), and antimicrobial susceptibility testing results. Eligible isolates were the first urinary E. coli or K. pneumoniae isolate per patient collected within 30 days; classified as not susceptible (NS) if antimicrobial susceptibility testing results were intermediate or resistant to each antibiotic tested. Four resistance phenotypes were identified: NS to fluoroquinolones (FQ), trimethoprim/sulfamethoxazole (SXT), nitrofurantoin (NTF), and extended-spectrum β-lactamase+/third-generation cephalosporin (ESBL+/3GC NS). Co-resistance phenotypes included all possible combinations of resistance to ≥ 2 drug classes.

RESULTS

Of 1,513,882 E. coli isolates and 250,719 K. pneumoniae isolates, 856,918 and 187,459 isolates with ≥ 1 resistance phenotype were included in the analysis, respectively. The most common resistance phenotypes were SXT NS for the E. coli isolates (44.8%) and NTF NS for the K. pneumoniae isolates (75.5%), while ESBL+/3GC NS comprised 11.2 and 5.9%, respectively. Among ESBL+/3GC NS E. coli isolates, 72.4, 56.7, and 46.6% were co-resistant to FQ, SXT, and FQ + SXT, respectively. For ESBL+/3GC NS K. pneumoniae isolates, 65.7 and 45.7% were co-resistant to SXT and FQ + SXT.

CONCLUSION

Both species exhibited high rates of co-resistance, emphasizing the need to raise awareness of co-resistance and of the unmet need for effective treatment options for uUTI.

Urinary tract infections in older adults: associated factors for extended-spectrum beta-lactamase production

Objective

Urinary tract infections (UTIs) due to extended-spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae are among the leading causes of morbidity and mortality in older adults. Identifying associated factors for ESBL production may contribute to more appropriate empirical treatment.

Materials and methods

This was a prospective observational study. Hospitalized patients of age > 65 with community-onset or hospital-acquired upper UTI due to E. coli or Klebsiella pneumoniae were included. A multivariate analysis was performed.

Results

A total of 97 patients were included. ESBL prevalence among UTIs with E. coli or Klebsiella pneumoniae was 69.1% (n = 67). CRP values at the time of UTI diagnosis were found to be significantly higher in the ESBL-producing group (p = 0.004). The multivariate analysis revealed that male gender (OR: 2.72, CI: 1.02-7.25), prior recurrent UTI (OR: 3.14, CI: 1.21-8.14), and the development of secondary bacteremia (OR: 4.95, CI: 1.03-23.89) were major associated factors for UTI in older adults due to ESBL-producing E. coli and Klebsiella pneumoniae.

Conclusion

Severe UTI in older men with a history of recurrent UTI may be a warning to the clinician for ESBL production in the setting of high ESBL prevalence. Carbapenems may be prioritized in the empirical treatment of patients with known risk factors for ESBL.

Implementation of an Automated Antibiotic Time-out at a Comprehensive Cancer Center

Background

Antimicrobial stewardship programs can optimize antimicrobial use and have been federally mandated in all hospitals. However, best stewardship practices in immunocompromised patients with cancer are not well established.

Methods

An antimicrobial time out, in the form of an email, was sent to physicians caring for hospitalized patients reaching 5 days of therapy for targeted antimicrobials (daptomycin, linezolid, tigecycline, vancomycin, imipenem/cilastatin, meropenem) in a comprehensive cancer center. Physicians were to discontinue the antimicrobial if unnecessary or document a rationale for continuation. This is a quasi-experimental, interrupted time series analysis assessing antimicrobial use during the following times: period 1 (before time-out: January 2007-June 2010) and period 2 (after time-out: July 2010-March/2015). The primary antimicrobial consumption metric was mean duration of therapy. Days of therapy per 1000 patient-days were also assessed.

Results

Implementation of the time-out was associated with a significant decrease in mean duration of therapy for the following antimicrobials; daptomycin: -0.89 days (95% confidence interval [CI], -1.38 to -.41); linezolid: -0.89 days (95% CI, -1.27 to -.52); meropenem: -0.97 days (95% CI, -1.39 to -.56); tigecycline: -1.41 days (95% CI, -2.19 to -.63); P < .001 for each comparison. Days of therapy/1000 patient-days decreased significantly for meropenem (-43.49; 95% CI, -58.61 to -28.37; P < .001), tigecycline (-35.47; 95% CI, -44.94 to -26.00; P < .001), and daptomycin (-9.47; 95% CI, -15.25 to -3.68; P = .002).

Discussion

A passive day 5 time-out was associated with reduction in targeted antibiotic use in a cancer center and could potentially be successfully adopted to several settings and electronic health records.

Prevalence of Extended-Spectrum β-Lactamases (ESBLs) Producing Aeromonas spp. Isolated from Lamellidens marginalis (Lamark, 1819) of Sewage-Fed Wetland: A Phenotypic and Genotypic Approach

The global rise of zoonotic bacteria resistant to multiple antimicrobial classes and the growing occurrence of infections caused by Aeromonas spp. resistant to β-lactam antibiotics pose a severe threat to animal and human health. However, the contribution of natural environments, particularly aquatic ecosystems, as ideal settings for the development and spread of antimicrobial resistance (AMR) is a key concern. Investigating the phenotypic antibiotic resistance and detection of β-lactamase producing Aeromonas spp. in Lamellidens marginalis, which inhabit all freshwater ecosystems of the Indian subcontinent, is essential for implications in monitoring food safety and drug resistance. In the present investigation, 92 isolates of Aeromonas spp. were recovered from 105 bivalves and screened for their antimicrobial resistance patterns. In vitro antibiotic resistance profiling showed a higher Multiple Antibiotic Resistance (MAR) index of 0.8 with the highest resistance against ampicillin/sulbactam (82%), while 58, 44, 39 and 38% of the isolates were resistant to cephalothin, erythromycin, cefoxitin and imipenem, respectively. PCR results revealed that these isolates carried the blaTEM gene (94%), which was followed by the blaCTX-M gene (51%) and the blaSHV gene (45%). A combination of blaSHV, blaCTX-M, and blaTEM genes was found in 17% of the isolates, indicating the presence of all three resistance genes. This is the first investigation which highlights the importance of multidrug-resistant Aeromonas spp. in L. marginalis. The identification of extended-spectrum-β-lactamases (ESBLs) genes demand the necessity of continuous surveillance and systematic monitoring, considering its potential health risks for both animals and human beings.

Long-term gut colonization with ESBL-producing Escherichia coli in participants without known risk factors from the southeastern United States

We evaluated gut carriage of extended spectrum beta lactamase producing Enterobacteriaceae (ESBL-E) in southeastern U.S. residents without recent in-patient healthcare exposure. Study enrollment was January 2021-February 2022 in Athens, Georgia, U.S. and included a diverse population of 505 adults plus 50 child participants (age 0-5). Based on culture-based screening of stool samples, 4.5% of 555 participants carried ESBL-Es. This is slightly higher than reported in studies conducted 2012-2015, which found carriage rates of 2.5-3.9% in healthy U.S. residents. All ESBL-E confirmed isolates (n=25) were identified as Escherichia coli. Isolates belonged to 11 sequence types, with 48% classified as ST131. Ninety six percent of ESBL-E isolates carried a blaCTX-M gene. Isolated ESBL-Es frequently carried virulence genes as well as multiple classes of antibiotic resistance genes. Long-term colonization was common, with 64% of ESBL-E positive participants testing positive when rescreened three months later. One participant yielded isolates belonging to two different E. coli sequence types that carried blaCTX-M-1 genes on near-identical plasmids, suggesting intra-gut plasmid transfer. Isolation of E. coli on media without antibiotics revealed that ESBL-E. coli typically made up a minor fraction of the overall gut E. coli population, although in some cases they were the dominant strain. ESBL-E carriage was not associated with a significantly different stool microbiome composition. However, some microbial taxa were differentially abundant in ESBL-E carriers. Together, these results suggest that a small subpopulation of US residents are long-term, asymptomatic carriers of ESBL-Es, and may serve as an important reservoir for community spread of these ESBL genes.

Clinical Risk Scores to Predict Nonsusceptibility to Trimethoprim-Sulfamethoxazole, Fluoroquinolone, Nitrofurantoin, and Third-Generation Cephalosporin Among Adult Outpatient Episodes of Complicated Urinary Tract Infection

Background

Clinical risk scores were developed to estimate the risk of adult outpatients having a complicated urinary tract infection (cUTI) that was nonsusceptible to trimethoprim-sulfamethoxazole (TMP-SMX), fluoroquinolone, nitrofurantoin, or third-generation cephalosporin (3-GC) based on variables available on clinical presentation.

Methods

A retrospective cohort study (1 December 2017-31 December 2020) was performed among adult members of Kaiser Permanente Southern California with an outpatient cUTI. Separate risk scores were developed for TMP-SMX, fluoroquinolone, nitrofurantoin, and 3-GC. The models were translated into risk scores to quantify the likelihood of nonsusceptibility based on the presence of final model covariates in a given cUTI outpatient.

Results

A total of 30 450 cUTIs (26 326 patients) met the study criteria. Rates of nonsusceptibility to TMP-SMX, fluoroquinolone, nitrofurantoin, and 3-GC were 37%, 20%, 27%, and 24%, respectively. Receipt of prior antibiotics was the most important predictor across all models. The risk of nonsusceptibility in the TMP-SMX model exceeded 20% in the absence of any risk factors, suggesting that empiric use of TMP-SMX may not be advisable. For fluoroquinolone, nitrofurantoin, and 3-GC, clinical risk scores of 10, 7, and 11 predicted a ≥20% estimated probability of nonsusceptibility in the models that included cumulative number of prior antibiotics at model entry. This finding suggests that caution should be used when considering these agents empirically in patients who have several risk factors present in a given model at presentation.

Conclusions

We developed high-performing parsimonious risk scores to facilitate empiric treatment selection for adult outpatients with cUTIs in the critical period between infection presentation and availability of susceptibility results.

Urinary tract infections in children from the Gulf Cooperation Council countries: a literature review (2011-2022)

Urinary tract infections (UTIs) are common healthcare-associated and community-acquired bacterial infections in children. Data on pediatric UTIs in the Gulf Cooperation Council (GCC) region (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) have not been collated. Our aim is to review the published literature on the risk factors, etiology, antimicrobial susceptibility, and treatment of pediatric (aged <18 years) UTIs from healthcare and community settings in the GCC countries.

High prevalence of β-lactam and fluoroquinolone resistance in various phylotypes of Escherichia coli isolates from urinary tract infections in Jiroft city, Iran

BACKGROUND

Urinary tract infection (UTI) is one of the most prevalent infectious diseases with worldwide health threatening. Antimicrobial resistant strains of Escherichia coli (E. coli) are a common cause of UTI which were identified as a treatment challenge. This study aimed to assay the prevalence of common β-lactam resistance genes including blaTEM, blaSHV, blaCTX-M and blaCMY and phenotypic resistance to commonly used β-lactam and fluoroquinolone antibiotics in UTIs. These factors were evaluated in various phylogenetic groups (phylotypes) of E. coli isolates. Real-time PCR was applied to detect β-lactam resistance genes and conventional PCR was used to determine the phylotypes. Phenotypic resistance against β-lactams (ceftazidime, cefotaxime, aztreonam and ceftriaxone) and fluoroquinolones (ciprofloxacin) were identified by the disc diffusion technique. The ability of extended spectrum β-lactamases (ESBLs) production in E. coli isolates was detected using the combined disc diffusion method.

RESULTS

The prevalence of resistance genes were 89.6% for blaTEM, 44.3% for blaCTX-M, 6.6% for blaSHV and 0.9% for blaCMY. The two high prevalent phylotypes were B2 (29.2%) and D (17.9%) followed by E (14.1%), F (9.4%), C (6.6%) and 10.3% of isolates were unknown in phylotyping. Disc diffusion results showed high prevalence of antibiotic resistance to cefotaxime (88.6%), aztreonam (83%), ceftireaxon (77.3%), ceftazidime (76.4%) and ciprofloxacin (55.6%). Totally, 52.8% of isolates were found as phenotypical ESBL-producers.

CONCLUSIONS

This study's results confirmed an explosion of antibiotic resistance amongst E. coli isolates from UTI against β-lactams and fluoroquinolones. Findings explain the necessity of deep changes in quantity and quality of drug resistance diagnosis and antibiotic therapy strategies. More studies are suggested to better and confident evaluations.

Optimization of Antimicrobial Stewardship Programs Using Therapeutic Drug Monitoring and Pharmacokinetics-Pharmacodynamics Protocols: A Cost-Benefit Review

PURPOSE

Antimicrobial stewardship programs are important for reducing antimicrobial resistance because they can readjust antibiotic prescriptions to local guidelines, switch intravenous to oral administration, and reduce hospitalization times. Pharmacokinetics-pharmacodynamics (PK-PD) empirically based prescriptions and therapeutic drug monitoring (TDM) programs are essential for antimicrobial stewardship, but there is a need to fit protocols according to cost benefits. The cost benefits can be demonstrated by reducing toxicity and hospital stay, decreasing the amount of drug used per day, and preventing relapses in infection. Our aim was to review the data available on whether PK-PD empirically based prescriptions and TDM could improve the cost benefits of an antimicrobial stewardship program to decrease global hospital expenditures.

METHODS

A narrative review based on PubMed search with the relevant studies of vancomycin, aminoglycosides, beta-lactams, and voriconazole.

RESULTS

TDM protocols demonstrated important cost benefit for patients treated with vancomycin, aminoglycosides, and voriconazole mainly due to reduce toxicities and decreasing the hospital length of stay. In addition, PK-PD strategies that used infusion modifications to meropenem, piperacillin-tazobactam, ceftazidime, and cefepime, such as extended or continuous infusion, demonstrated important cost benefits, mainly due to reducing daily drug needs and lengths of hospital stays.

CONCLUSIONS

TDM protocols and PK-PD empirically based prescriptions improve the cost-benefits and decrease the global hospital expenditures.

Antimicrobial Resistance in Urinary Tract Infections: Is There an Issue and Does It Matter?

Antimicrobial resistance (AMR) has increased substantially among community-acquired uropathogens that cause urinary tract infections (UTI), limiting the availability of effective oral antibiotic treatments. This review includes coverage of an expert-led Learning Lounge, symposium session, and several poster presentations, that took place between 20th–22nd October 2022 as part of IDWeek2022 in Washington, D.C., USA. An immersive Learning Lounge, sponsored by GSK, opened with Keith Kaye, Department of Medicine, Rutgers–Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA, who illuminated the concerns of AMR in community-acquired UTIs, delivering contemporary surveillance data, and outlined how in vitro data may translate into practical advice. This led fittingly to Erin McCreary, Division of Infectious Diseases, Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania, USA, who enquired whether enough is being done in clinical practice regarding community-acquired infections, highlighting the importance of antimicrobial stewardship (AMS), and galvanising the audience to adapt healthcare settings to the changing landscape. The scientific programme also included three data-rich posters that showcased Kaye’s surveillance data on Escherichia coli and Klebsiella pneumoniae co-resistance, along with the geographical distribution of K. pneumoniae. An insightful poster by Claire Trennery, Value Evidence Outcomes, GSK, Brentford, UK, considered the patient perspective of UTI symptoms in defining antibiotic treatment success, and two posters presented by Rodrigo Mendes, JMI Laboratories, North Liberty, Iowa, USA, examined in vitro global surveillance data of emerging antimicrobial treatments.

Trends in the Rates of Extended-Spectrum-β-Lactamase-Producing Enterobacterales Isolated from Urine Cultures during the COVID-19 Pandemic in Ontario, Canada

Worldwide, extended-spectrum β-lactamase (ESBL) rates are increasing at an alarming level with increasing rates of health care exposures, international travel, and antibiotic usage. In this study, we investigated whether enhanced social isolation, travel restrictions, and the reduced use of antibiotics in Ontario, Canada during coronavirus disease 2019 (COVID-19) pandemic had an impact on ESBL rates in urine cultures collected from the community and long-term-care (LTC) facilities across the province. Data from a total of 8.6 million urine cultures performed at LifeLabs Ontario from 2016 to 2021 were utilized for analysis. ESBL-producing Escherichia coli (ESBL Escherichia coli) and ESBL Klebsiella pneumoniae were identified using standard operating procedures. Data trends were estimated by interrupted time series (ITS) regression analysis. Among 2.3 million positive urine cultures, 48.9% and 7.2% grew E. coli and K. pneumoniae, of which 5.8% and 3.3% produced ESBLs, respectively. While the overall rate of ESBL isolation was higher in the pandemic period than in the prepandemic period, by ITS regression analysis of the monthly rates of ESBL isolation, decreasing trends were noted for ESBL E. coli in both the community and LTC facilities and for ESBL K. pneumoniae in the community. The ESBL K. pneumoniae rates in LTC facilities continued to increase throughout the COVID-19 period. By subgroup analysis for different genders, age groups, and local health integration network (LHIN) units, similar trends were seen in most cases (P < 0.05), except for a few densely populated LHINs where rate changes were not statistically significant. IMPORTANCE Community-onset urinary tract infections (UTIs) caused by ESBL-producing Enterobacterales, particularly E. coli and K. pneumoniae, are a major public health concern. In this study, we assessed the impact of COVID-19 on ESBL rates in urine cultures in Ontario, Canada. Our results show the recent epidemiology of ESBL-producing Enterobacterales in urine cultures from both the community and LTC facilities in Ontario, Canada, and the impact of COVID-19 restrictions on ESBL trends for the entire province as well as different subgroups of the population based on demographic and geographic characteristics. Our results may have important public health implications in the context of the gradual easing of COVID-19 restrictions.

Increasing Prevalence of Pediatric Community-acquired UTI by Extended Spectrum β-Lactamase-producing E. coli: Cause for Concern

BACKGROUND

Antimicrobial resistance and emerging spectrum-β-lactamase (ESBL) infections are a rising concern in public health. Despite the increasing prevalence of community-acquired (CA) ESBL-E. coli UTIs, there is little data on the antibiotic resistance profiles of this bacterial strain in the pediatric population. We review antibiotic resistance profile and rising trend in pediatric ESBL-E. coli UTI presentation at our pediatric hospital.

METHODS

This retrospective study reviewed data drawn from the infectious disease database at our pediatric hospital for all patients whose urine culture grew ESBL-E. coli from 01/2015 to 01/2021. Demographic information and antimicrobial susceptibility test results for ESBL-E. coli isolates from CA-UTIs were collected. Annual changes in resistance to antimicrobial agents and average annual percent change in ESBL-E. coli UTI presentation over the study period are reported.

RESULTS

From 01/2015 to 01/2021, 6403 urine cultures at our hospital grew E. coli. Of these, 169 urine cultures from 135 children grew ESBL-E. coli. The study population was 57% male (77) with a mean age of 6.9 ± 6.2 years and multiethnic. CA-UTI by ESBL-producing E. coli accounted for 2.62% of total E. coli UTIs within the study period and increased from 0.97% in 2015 to 3.54% in 2020 by an average of 0.51% each year.

CONCLUSIONS

These findings demonstrate an increase in CA-ESBL E. coli UTIs in children. We observed most isolates demonstrated multidrug resistance. As CA-ESBL E. coli UTIs are associated with prolonged hospitalization and increased morbidity, our findings highlight the rising trend in pediatric CA-ESBL E. coli UTI.

Clonal groups of extended-spectrum β-lactamase and biofilm producing uropathogenic Escherichia coli in Iran

Pathogenicity of a bacterium is affected by the social characteristics of the population and environmental factors. The ability of biofilm formation among β-lactamase-producing uropathogenic Escherichia coli (UPEC) could facilitate the exchange of antibiotic-resistance genes, which resulted in widespread dissemination of antibacterial drug resistance. We investigated the prevalence of biofilm and β-lactamase producing UPECs among patients with urinary tract infection (UTI) in two cities with different demographics and climates in Iran. A total of 265 E. coli was isolated from patients with UTIs from two referral hospitals (n = 191) and two outpatient clinics (n = 74) in Isfahan and Zahedan, Iran. Production of curli and cellulose, and, biofilm formation was investigated using Congo red agar and microtiter plate methods, respectively. Biofilm producing (BFP) isolates (n = 107) were further characterized using rep-PCR, antimicrobial susceptibility testing and extended-spectrum β-lactamase (ESBL)/AmpC phenotypic production. Isolates were also screened for the presence of carbapenemase, ESBL and AmpC genes using multiplex PCR.   High diversity was found among BFP strains in both cities, with 58% strains producing ESBL and 21% producing AmpC. ESBL (98%), AmpC (50%) and carbapenemase genes (40%) were identified in BFP strains with ESBL-positive phenotype, respectively. The prevalence of BFP strains, antibiotic resistance and β-lactamase genes in Zahedan, a low socioeconomic city with a warm climate, was significantly higher than that of Isfahan. High prevalence of biofilm and β-lactamase producing UPEC strains among strains from Zahedan suggests that socioeconomic status and environmental factors might have a role in pathogenicity of the strains.

Antimicrobial resistance patterns of bacterial pathogens recovered from the urine of patients at Canadian hospitals from 2009 to 2020

Objectives

To investigate in vitro susceptibility patterns of bacterial pathogens recovered from the urine of outpatients (isolates from outpatient clinics or emergency departments) and hospital inpatients across Canada from 2009 to 2020 as part of the CANWARD study.

Methods

Canadian hospital microbiology laboratories submitted bacterial pathogens cultured from urine to the CANWARD study coordinating laboratory on an annual basis (January 2009 to December 2020). Antimicrobial susceptibility testing was performed by CLSI broth microdilution, with MICs interpreted by current CLSI breakpoints.

Results

In total, 4644 urinary pathogens were included in this study. Escherichia coli was recovered most frequently (53.3% of all isolates), followed by Enterococcus faecalis, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa and Staphylococcus aureus. Together, these six species accounted for 84.2% of study isolates. Nitrofurantoin demonstrated excellent in vitro activity versus E. coli, with 97.6% of outpatient and 96.1% of inpatient isolates remaining susceptible. In contrast, E. coli susceptibility rates were lower for ciprofloxacin (outpatient 79.5%, inpatient 65.9%) and trimethoprim/sulfamethoxazole (outpatient 75.2%, inpatient 73.5%). The percentage of E. coli isolates that were phenotypically positive for ESBL production significantly increased from 4.2% (2009-11) to 11.3% (2018-20). A similar although less pronounced temporal trend was observed with ESBL-producing K. pneumoniae.

Conclusions

E. coli was the pathogen most frequently recovered from the urine of Canadian patients, and the proportion of isolates that were ESBL producers increased over time. Susceptibility data presented here suggest that ciprofloxacin and trimethoprim/sulfamethoxazole may be suboptimal for the empirical treatment of complicated urinary infections.

A Case-Control Study Evaluating Risk Factors and Outcomes of Hospitalized Children With ESBL-UTI

Urinary tract infections (UTIs) are among the most common causes of hospitalization in children, with a rising prevalence of extended-spectrum beta-lactamase-producing organisms (ESBL). The purpose of this study was to identify risk factors and treatment outcomes of children with ESBL-UTI. A retrospective case-control study of hospitalized children was performed from July 2014 till December 2017. Medical records from patients with a positive urine culture were reviewed and included in the study if they met criteria for UTI. Cases were defined as ESBL-UTI, while controls were defined as non-ESBL-UTI patients. This study confirmed that there are certain risk factors, such as previous UTI, recent antibiotic use, urinary tract abnormalities, recent hospital admission, and nonrenal comorbidities, that are associated with ESBL-UTI. Most of the patients with ESBL-UTI responded to discordant antibiotics. Other significant outcomes in patients with ESBL-UTI included a longer length of stay and longer intravenous antibiotic therapy.

Epidemiology of Plasmid Lineages Mediating the Spread of Extended-Spectrum Beta-Lactamases among Clinical Escherichia coli

The prevalence of extended-spectrum beta-lactamases (ESBLs) among clinical isolates of Escherichia coli has been increasing, with this spread driven by ESBL-encoding plasmids. However, the epidemiology of ESBL-disseminating plasmids remains understudied, obscuring the roles of individual plasmid lineages in ESBL spread. To address this, we performed an in-depth genomic investigation of 149 clinical ESBL-like E. coli isolates from a tertiary care hospital. We obtained high-quality assemblies for 446 plasmids, revealing an extensive map of plasmid sharing that crosses time, space, and bacterial sequence type boundaries. Through a sequence-based network, we identified specific plasmid lineages that are responsible for the dissemination of major ESBLs. Notably, we demonstrate that IncF plasmids separate into 2 distinct lineages that are enriched for different ESBLs and occupy distinct host ranges. Our work provides a detailed picture of plasmid-mediated spread of ESBLs, demonstrating the extensive sequence diversity within identified lineages, while highlighting the genetic elements that underlie the persistence of these plasmids within the clinical E. coli population. IMPORTANCE The increasing incidence of nosocomial infections with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli represents a significant threat to public health, given the limited treatment options available for such infections. The rapid ESBL spread is suggested to be driven by localization of the resistance genes on conjugative plasmids. Here, we identify the contributions of different plasmid lineages in the nosocomial spread of ESBLs. We provide further support for plasmid-mediated spread of ESBLs but demonstrate that some ESBL genes rely on dissemination through plasmids more than the others. We identify key plasmid lineages that are enriched in major ESBL genes and highlight the encoded genetic elements that facilitate the transmission and stable maintenance of these plasmid groups within the clinical E. coli population. Overall, our work provides valuable insight into the dissemination of ESBLs through plasmids, furthering our understating of factors underlying the increased prevalence of these genes in nosocomial settings.

Prevalence of Multidrug-Resistant Diarrheagenic Escherichia coli in Asia: A Systematic Review and Meta-Analysis

Diarrhea is one of the leading causes of morbidity and mortality in developing countries. Diarrheagenic Escherichia coli (DEC) is an important bacterial agent for diarrhea in infants, children, and international travelers, and accounts for more than 30% of diarrheal cases in children less than 5 years old. However, the choices of antimicrobial agents are now being limited by the ineffectiveness of many first-line drugs, in relation to the emergence of antimicrobial-resistant E. coli strains. The aim of this systematic review and meta-analysis was to provide an updated prevalence of antimicrobial-resistant DEC in Asia. A comprehensive systematic search was conducted on three electronic databases (PubMed, ScienceDirect, and Scopus), where 40 eligible studies published between 2010 and 2022 were identified. Using meta-analysis of proportions and a random-effects model, the pooled prevalence of DEC in Asian diarrheal patients was 22.8% (95% CI: 16.5–29.2). The overall prevalence of multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL)-producing DEC strains was estimated to be 66.3% (95% CI: 58.9–73.7) and 48.6% (95% CI: 35.1–62.1), respectively. Considering antimicrobial drugs for DEC, the resistance prevalence was highest for the penicillin class of antibiotics, where 80.9% of the DEC isolates were resistant to amoxicillin and 73.5% were resistant to ampicillin. In contrast, resistance to carbapenems such as imipenem (0.1%), ertapenem (2.6%), and meropenem (7.9%) was the lowest. The relatively high prevalence estimation signifies that the multidrug-resistant DEC is a public health threat. Effective antibiotic treatment strategies, which may lead to better outcomes for the control of E. coli infections in Asia, are necessary.

Assessment of nationally recommended antibiotics for treatment of UTI in U.S.-Mexico border emergency departments

BACKGROUND

Urinary tract infections (UTIs) seen in the emergency department are commonly treated as an outpatient with oral antibiotics. Given that antibiotics are available for over-the-counter purchase in Mexico, there is speculation that potential misuse and overuse of antibiotics in United States-Mexico border areas could lead to antibiotic resistance patterns that would render some empiric treatments for UTIs less effective. The purpose of this study was to examine the effectiveness of Infectious Disease Society of America (IDSA) guideline-recommended antibiotics for treatment of outpatient UTI diagnosed in the emergency department. Data were collected from a county hospital on the U.S.-Mexico border with a metropolitan area of over 2 million people. Secondary analysis included frequency of urine culture isolated, resistance rates of urine pathogens, and prescriber habits.

METHODS

This study was a retrospective chart review of adult patients diagnosed and treated for UTI from August 1, 2019, to February 29, 2020. Culture results of included patients were analyzed against in vitro-tested antibiotics. Bacterial isolate frequency, resistance rates, and prescribing habits were collected.

RESULTS

A total of 985 patient charts were reviewed, of which 520 patients met inclusion criteria for analysis of prescribing habits. Of these, 329 positive bacterial culture growths were included in the analysis of antibiotic resistance rates. Oral antibiotics with comparatively lower resistance rates were amoxicillin/clavulanate, cefdinir, cefuroxime, and nitrofurantoin. Oral antibiotics with notably high resistance rates included trimethoprim-sulfamethoxazole (TMP-SMX), tetracycline, ciprofloxacin, levofloxacin, and cephalexin. Nitrofurantoin was prescribed most frequently for outpatient treatment of UTI/cystitis (41.6%) while cephalexin was the most commonly prescribed antibiotic for outpatient treatment of pyelonephritis (50%).

CONCLUSION

Our findings suggest that, while part of standard IDSA guidelines, fluoroquinolones and TMP-SMX are not ideal empiric antibiotics for treatment of outpatient UTI in the U.S.-Mexico border region studied due to high resistance rates. Although not listed as first line agents per current IDSA recommendations, 2nd and 3rd generation cephalosporins, and amoxicillin/clavulanate would be acceptable options given resistance patterns demonstrated in accordance with IDSA allowance for tailoring selection to local resistance. Nitrofurantoin appears to be consistent with recommendations and demonstrates a favorable resistance profile for treatment of outpatient UTI within this region.

Treatment and Epidemiology of Third-Generation Cephalosporin-Resistant Urinary Tract Infections

BACKGROUND AND OBJECTIVES

Limited data are available on the contemporary epidemiology, clinical management, and health care utilization for pediatric urinary tract infection (UTI) due to third-generation cephalosporin-resistant Enterobacterales (G3CR) in the United States. The objective is to describe the epidemiology, antimicrobial treatment and response, and health care utilization associated with G3CR UTI.

METHODS

Multisite, matched cohort-control study including children with G3CR UTI versus non-G3CR UTI. UTI was defined as per American Academy of Pediatrics guidelines, and G3CR as resistance to ceftriaxone, cefotaxime, or ceftazidime. We collected data from the acute phase of illness to 6 months thereafter.

RESULTS

Among 107 children with G3CR UTI and 206 non-G3CR UTI with documented assessment of response, the proportion with significant improvement on initial therapy was similar (52% vs 57%; odds ratio [OR], 0.81; 95% confidence interval [CI], 0.44-1.50). Patients with G3CR were more frequently hospitalized at presentation (38% vs 17%; OR, 3.03; 95% CI, 1.77-5.19). In the follow-up period, more patients with G3CR had urine cultures (75% vs 53%; OR, 2.61; 95% CI, 1.33-5.24), antimicrobial treatment of any indication (53% vs 29%; OR, 2.82; 95% CI, 1.47-5.39), and subspecialty consultation (23% vs 6%; OR, 4.52; 95% CI, 2.10-10.09). In multivariate analysis, previous systemic antimicrobial therapy remained a significant risk factor for G3CR UTI (adjusted OR, 1.91; 95% CI, 1.06-3.44).

CONCLUSIONS

We did not observe a significant difference in response to therapy between G3CR and susceptible UTI, but subsequent health care utilization was significantly increased.

Epidemiology of Complicated Urinary Tract Infections due to Enterobacterales among Adult Patients Presenting in Emergency Departments Across the United States

In this multicenter study of adult patients who presented to the emergency department with an Enterobacterales complicated urinary tract infection (cUTI), high rates of resistance and co-resistance to commonly used oral antibiotics (fluoroquinolones, trimethoprim-sulfamethoxazole, nitrofurantoin, and third-generation cephalosporins) were observed.

Retrospective Cohort Study of the 12-Month Epidemiology, Treatment Patterns, Outcomes, and Healthcare Costs Among Adult Patients with Complicated Urinary Tract Infections

Background

Limited data are available in the United States on the 12-month epidemiology, outpatient (OP) antibiotic treatment patterns, outcomes, and costs associated with complicated urinary tract infections (cUTIs) in adult patients.

Methods

A retrospective observational cohort study of adult patients with incident cUTIs in IBM MarketScan Databases between 2017 and 2019 was performed. Patients were categorized as OP or inpatient (IP) based on initial setting of care for index cUTI and were stratified by age (<65 years vs ≥65 years). OP antibiotic treatment patterns, outcomes, and costs associated with cUTIs among adult patients over a 12-month follow-up period were examined.

Results

During the study period, 95 322 patients met inclusion criteria. Most patients were OPs (84%) and age <65 years (87%). Treatment failure (receipt of new unique OP antibiotic or cUTI-related ED visit/IP admission) occurred in 23% and 34% of OPs aged <65 years and ≥65 years, respectively. Treatment failure was observed in >38% of IPs, irrespective of age. Across both cohorts and age strata, >78% received ≥2 unique OP antibiotics, >34% received ≥4 unique OP antibiotics, >16% received repeat OP antibiotics, and >33% received ≥1 intravenous (IV) OP antibiotics. The mean 12-month cUTI-related total health care costs were $4697 for OPs age <65 years, $8924 for OPs age >65 years, $15 401 for IPs age <65 years, and $17 431 for IPs age ≥65 years.

Conclusions

These findings highlight the substantial 12-month health care burden associated with cUTIs and underscore the need for new outpatient treatment approaches that reduce the persistent or recurrent nature of many cUTIs.

Epidemiology of urinary tract infection in adults caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae - a case-control study from Qatar

•

Urinary tract infection (UTI) caused by extended-spectrum beta-lactamase (ESBL)-producing organisms is a serious concern in the adult population.

•

Escherichia coli is the primary organism causing ESBL-UTI.

•

Avoiding indiscriminate use of antibiotics may reduce the incidence of ESBL-UTI.

Background

Community-acquired urinary tract infection (UTI) is the most common infection caused by extended-spectrum beta-lactamase (ESBL)-producing organisms.

Aim

to estimate the prevalence of ESBL-UTI in adults and to identify potential risk factors that may predispose to ESBL-UTI.

Methods

A retrospective study involving adult patients with UTI caused by ESBL-producing organisms was undertaken. Patients with UTI caused by non-ESBL-producing organisms represented the control group.

Results

In total, 1100 UTI isolates were included in the study, 277 of which were ESBL positive. The prevalence rate was 25.2%. The mean age of patients was 55.87 years. On univariate analysis, prior history of UTI or ESBL-UTI, invasive urological procedure within preceding 3 months, hospital admission within preceding 3 months, and exposure to antibiotics were found to be significant risk factors for ESBL-UTI. On multi-variate analysis, use of cephalosporins [adjusted odds ratio (OR) 1.61, P=0.048], previous ESBL-UTI (adjusted OR 2.67, P<0.001), and invasive urological procedure in the preceding year (adjusted OR 1.61, P=0.022) were found to be independent risk factors for ESBL-UTI.

Conclusions

In Qatar, the prevalence of ESBL-UTI in adults is modest. Recent exposure to antibiotics, previous ESBL-UTI and invasive urological procedures were found to be independent risk factors for ESBL-UTI.

Examining the combination of cefixime and amoxicillin/clavulanate against extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates

INTRODUCTION

Community-acquired urinary tract infections (UTIs) caused by extended spectrum beta-lactamase (ESBL)-producing Escherichia coli have limited oral therapeutic options and pose significant clinical challenges. The goal of this study was to evaluate the in vitro synergy between CFM and AMC against ESBL E. coli with aims to identify an oral treatment option for UTIs.

METHODS

Minimum inhibitory concentrations (MICs) of CFM in the presence of AMC were determined for 46 clinical isolates by placing a CFM Etest on a plate with AMC impregnated in the agar. Isolates with CFM MIC ≤1 µg/ml in the presence of AMC were considered susceptible to the CFM and AMC combination. Five isolates were then selected for further testing using time-kill analysis in the presence of CFM, AMC, and CFM with AMC. Time-kill curves were plotted to determine synergy over 24 hours.

RESULTS

AMC improved the activity of CFM against ESBL E. coli isolates by 128-fold in the Etest analysis with 85% of tested isolates being susceptible to the combination. Four-fold or greater reduction in CFM MIC was exhibited in 44 of 46 (96%) isolates when in the presence of AMC. Synergy and bactericidal activity between CFM and AMC were exhibited in each of the five isolates tested by time-kill analysis.

DISCUSSION/CONCLUSION

This study found that AMC improves the activity of CFM against ESBL E. coli and that this antibiotic combination has potential as an oral therapeutic option to treat ESBL E. coli UTIs.

Antimicrobial Stewardship Programs: A Review of Strategies to Avoid Polymyxins and Carbapenems Misuse in Low Middle-Income Countries

Antibiotics misuse and overuse are concerning issues worldwide, especially in low middle-income countries. These practices contribute to the increasing rates of antimicrobial resistance. One efficient strategy to avoid them is antimicrobial stewardship programs. In this review, we focus on the possible approaches to spare the prescription of polymyxins and carbapenems for the treatment of Acinetobacter baumannii, carbapenem-resistant Enterobacterales, and Pseudomonas aeruginosas infections. Additionally, we highlight how to implement cumulative antibiograms and biomarkers to a sooner de-escalation of antibiotics.

A multicenter analysis of trends in resistance in urinary Enterobacterales isolates from ambulatory patients in the United States: 2011-2020

BACKGROUND

Urinary tract infections (UTIs), which are usually caused by bacteria in the Enterobacterales family, are a common reason for outpatient visits. Appropriate empiric therapy for UTIs requires an understanding of antibiotic resistance in the community. In this nationwide study, we examined trends in antibiotic resistance in urinary Enterobacterales isolates from ambulatory patients in the United States (US).

METHODS

We analyzed the antimicrobial susceptibility profiles (extended-spectrum beta-lactamase [ESBL]-producing phenotype and not susceptible [NS] to beta-lactams, trimethoprim/sulfamethoxazole [TMP/SMX], fluoroquinolones [FQ], or nitrofurantoin [NFT]) of 30-day non-duplicate Enterobacterales isolates from urine cultures tested at ambulatory centers in the BD Insights Research Database (2011-2020). The outcome of interest was the percentage of resistant isolates by pathogen and year. Multi-variable generalized estimating equation models were used to assess trends in resistance over time and by additional covariates.

RESULTS

A total of 338 US facilities provided data for > 2.2 million urinary Enterobacterales isolates during the 10-year study. Almost three-quarters (72.8%) of Enterobacterales isolates were Escherichia coli. Overall unadjusted resistance rates in Enterobacterales isolates were 57.5%, 23.1%, 20.6%, and 20.2% for beta-lactams, TMP/SMX, FQ, and NFT, respectively, and 6.9% had an ESBL-producing phenotype. Resistance to two or more antibiotic classes occurred in 16.4% of isolates and 5.5% were resistant to three or more classes. Among isolates with an ESBL-producing phenotype, 70.1%, 59.9%, and 33.5% were NS to FQ, TMP/SMX, and NFT, respectively. In multivariable models, ESBL-producing and NFT NS Enterobacterales isolates increased significantly (both P < 0.001), while other categories of resistance decreased. High rates (≥ 50%) of beta-lactam and NFT resistance were observed in Klebsiella isolates and in non-E. coli, non-Klebsiella Enterobacterales isolates.

CONCLUSIONS

Antimicrobial resistance was common in urinary Enterobacterales isolates. Isolates with an ESBL-producing phenotype increased by about 30% between 2011 and 2020, and significant increases were also observed in NFT NS Enterobacterales isolates. Resistance rates for all four antibiotic classes were higher than thresholds recommended for use as empiric therapy. Non-E. coli Enterobacterales isolates showed high levels of resistance to commonly used empiric antibiotics, including NFT. These data may help inform empiric therapy choices for outpatients with UTIs.

What Left for Us for Urinary Tract Infection Treatment? An Experience from the South of Iran

Background:

The aim of the study is to define the prevalence and antimicrobial susceptibility pattern of bacteria from cases of urinary tract infections (UTIs).

Materials and Methods:

A retrospective analysis of urinary pathogens and their antimicrobial susceptibility was done on urine cultures at Shiraz University Laboratory from 2015 to 2017. Antimicrobial susceptibility tests have done using the disk-diffusion technique as per the standard of CSLI.

Results:

During 2 years of study, 3489 samples were culture positive. Escherichia coli was the dominant isolate (84%), followed by Klebsiella spp. (10.7%) and Enterococci spp. (2,2%). The overall resistance rates to trimethoprim-sulfamethoxazole, ceftriaxone, and ciprofloxacin were 56.1%, 47.2%, and 37%, respectively. The most frequently isolated bacteria were E. coli, which had resistance rates of 58.6%, 49.1% to TMP-STX, and cefixime, also sensitivity rates of 95.1% to nitrofurantoin (FM).

Conclusions:

In the study area, resistance rates to fluoroquinolones and cephalosporins were high. Because most isolates were sensitive to FM and aminoglycoside, they are suggested as appropriate antimicrobials for empirical treatment of UTIs before available urine culture results.

Fosfomycin vs Ertapenem for Outpatient Treatment of Complicated Urinary Tract Infections: A Multicenter, Retrospective Cohort Study

Background

We sought to determine the comparative efficacy of fosfomycin vs ertapenem for outpatient treatment of complicated urinary tract infections (cUTIs).

Methods

We conducted a multicenter, retrospective cohort study involving patients with cUTI treated with outpatient oral fosfomycin vs intravenous ertapenem at 3 public hospitals in Los Angeles County between January 2018 and September 2020. The primary outcome was resolution of clinical symptoms 30 days after diagnosis.

Results

We identified 322 patients with cUTI treated with fosfomycin (n = 110) or ertapenem (n = 212) meeting study criteria. The study arms had similar demographics, although patients treated with ertapenem more frequently had pyelonephritis or bacteremia while fosfomycin-treated patients had more retained catheters, nephrolithiasis, or urinary obstruction. Most infections were due to extended-spectrum β-lactamase–producing E. coli and Klebsiella pneumoniae, 80%–90% of which were resistant to other oral options. Adjusted odds ratios for clinical success at 30 days, clinical success at last follow-up, and relapse were 1.21 (95% CI, 0.68–2.16), 0.84 (95% CI, 0.46–1.52), and 0.94 (95% CI, 0.52–1.70) for fosfomycin vs ertapenem, respectively. Patients treated with fosfomycin had significant reductions in length of hospital stay and length of antimicrobial therapy and fewer adverse events (1 vs 10). Fosfomycin outcomes were similar irrespective of duration of lead-in intravenous (IV) therapy or fosfomycin dosing interval (daily, every other day, every third day).

Conclusions

These results would support the conduct of a randomized controlled trial to verify efficacy. In the meantime, they suggest that fosfomycin may be a reasonable stepdown from IV antibiotics for cUTI.

The efficacy of fosfomycin trometamol in prevention of postoperative urinary tract infection in pregnant women after endoscopic procedures: open clinical trial

Background

Fosfomycin tromethamine is recommended (category B) for the treatment of urinary tract infections in pregnant women. We aimed to evaluate the efficacy of single-dose preoperative fosfomycin tromethamine in the prevention of urinary tract infection in pregnant women who underwent lower urinary tract endoscopic surgeries.

Methodology

The subjects of this study were pregnant women who underwent lower urinary tract endoscopic procedures. All patients received Fosfomycin tromethamine1 packet (3 g) dissolved in water the day before surgery. Routine pre- and postoperative urine analysis and urine cultures were performed when needed. Patients were monitored for urinary tract infections and the side effects of the drug. Moreover, maternal and fetal complications were monitored.

Results

The study was conducted on 31 pregnant women with a mean age of 24.48 ± 5.35 years. The endoscopic procedures were as follows: 28 (90.3%) DJ ureteric insertions for hydronephrosis, 2 (6.5%) urinary bladder stones, and cystoscopy (3.2%) for gross hematuria. Two (6.5%) patients had postoperative asymptomatic bacteriuria that resolved with oral antibiotic therapy.

Conclusion

Fosfomycin tromethamine is safe in preventing urinary tract infection and decreases the need for postoperative parenteral antibiotics in pregnant women who require lower urinary tract endoscopic procedures.

Antibiotic resistance pattern of uropathogenic Escherichia coli isolated from children with symptomatic urinary tract infection in Moscow, Russia

Background and Aim: Uropathogenic Escherichia coli (UPEC) is commonly involved in urinary tract infections (UTIs), which are generally treated with antibiotics. However, the emergence of multidrug-resistant (MDR) strains of UPEC has made the treatment difficult. There is thus a need to continuously assess their sensitivity to antibiotics. This study aimed to determine the antibiotic resistance patterns and MDR phenotypes of UPEC strains isolated from children diagnosed with UTIs at the Russian Children's Clinical Hospital in Moscow, Russia. Materials and Methods: Kirby–Bauer's disc diffusion method was used to study the sensitivity to antibiotics of 106 UPEC isolates from urine specimens from children (aged from 9 months to 18 years old) diagnosed with UTIs. The results were interpreted in accordance with the Clinical and Laboratory Standards Institute guidelines and the correlations of variables with the degree to which each antibiotic inhibited the UPEC strains in terms of diameter on the disc were determined using Spearman's rank correlation test. A t-test and principal component analysis were performed to visualize the correlations of the susceptibility of UPEC to antibiotics with the age and sex of the patients. Statistical significance was set at p≤0.05. Results: Among the 106 UPEC strains tested, none (0%) showed resistance to fosfomycin (FO), while 84 (79.2%) were resistant (R) to at least one antibiotic. The highest rates of resistance were observed to amoxicillin (69.8%), ampicillin (62.3%), cefazolin (39.6%), trimethoprim (TR) (37.7%), ceftriaxone (34.9%), and tetracycline (33.0%). Interestingly, 22 (20.8%) strains were R to imipenem. UPEC isolates from males aged 1-6 years were more R to antibiotics than those from the other groups, with the exception of TR, to which UPEC isolates from females aged 13-18 years old were less sensitive (S). The multidrug-resistance (MDR) index ranged between 0.00 and 0.75 and we found that more than a quarter of UPEC (31/106) had an MDR index ≥0.5 and only 22 (20.7%) strains were S to all antibiotics tested (MDR index=0). Finally, Spearman's rank correlation test showed that, with the exception of FO, there were correlations between the inhibition diameters of all other antibiotics. Conclusion: FO is the only antibiotic to which all UPECs were S and may be suggested as the first line of treatment for UPEC. Further research is needed to continue monitoring antibiotic resistance and to investigate the genetic features associated with such resistance observed in this study.

Antibiotic resistance and ESBL production in Escherichia coli from various sources in Aba metropolis, Nigeria

BACKGROUND

The increase in multidrug resistance (MDR) among pathogenic bacteria responsible for infectious diseases has led to lack of effectiveness of some antibiotics. The ability of Escherichia coli to harbor resistant genes has made the treatment of infections a major challenge. This study was carried out to assess antibiotic resistance and extended-spectrum beta-lactamase (ESBL) production of E. coli from various sources in Aba metropolis, Nigeria.

RESULTS

From a total of 350 samples collected from clinical and non-clinical sources, 137 were presumptively identified as E. coli by standard phenotypic methods and 83 were confirmed as E. coli by the detection of E. coli specific 16S rRNA gene fragments. The majority of these isolates (52, 62.7%) were from non-clinical sources. The clinical isolates, however, exhibited a higher level of resistance against 62.5% of tested antibiotics. Both group of isolates exhibited similar levels (58.1% vs 53.9%) of MDR, though. A low rate of ESBL production was observed (1.2%) following phenotypic detection of ESBL-producing abilities using the double-disc synergy test. An assessment of the presence of three beta-lactamase gene genotypes (bla_TEM, bla_SHV and bla_CTX-M) revealed that none of the three predominant ESBL genotypes was identified in this study.

CONCLUSIONS

This study reports high levels of antibiotic resistance in both clinical and non-clinical E. coli isolates. Though higher rates of resistance were observed among the non-clinical isolates, both group of organisms had similar levels of MDR. Strikingly, however, was the low level of ESBL producers detected in this study and the absence of the three main genotypes associated with ESBL production in this study.

Uropathogens Antimicrobial Sensitivity and Resistance Pattern From Outpatients in Balochistan, Pakistan

Objective To determine the pattern of microbes responsible for urinary tract infections and their susceptibility to different antibiotics. Method This is a cross-sectional study conducted at Quetta, Pakistan. The urine samples of 400 patients were collected and sent for culture and sensitivity analysis. The results were recorded on an excel datasheet. Descriptive statistics were used to describe the data. Results Out of 400 urine samples, 266 samples were culture positive for microorganisms. The most common organism on analysis was Escherichia coli 123/266 (46.24%) followed by Staphylococcus saprophyticus 59/266 (22.18%) and Klebsiella pneumonia 49/266 (18.42%). Gram-negative microorganisms were most susceptible to fosfomycin, cefoperazone/sulbactam, and meropenem. Gram-positive microorganisms were most susceptible to fosfomycin, cefoperazone/sulbactam, meropenem, and amoxicillin/clavulanate. High rates of resistance in E. coli were observed to most commonly prescribed broad-spectrum antibiotics; ceftriaxone (64.35%), cefotaxime (76.54%), ceftazidime (49.43%), cefepime (53.44%), levofloxacin (71.26%), and amoxicillin/clavulanate (70.31%). E. coli was the major multidrug-resistant organism. Conclusion High rates of antibiotic resistance and multi-drug resistance were revealed in this study due to the widespread and injudicious use of broad-spectrum antibiotics. Thus, it is highly recommended to regulate the pharmacies. Physicians should judiciously prescribe antibiotics and practice the culture and sensitivity of urine samples rather than blind prescription. Continued surveillance on uropathogens prevalence and resistance, new and next-generation antibiotics, and rapid diagnostic tests to differentiate viral from bacterial infections is the need of time.

Management of urinary tract infections and antibiotic susceptibility patterns of bacterial isolates

AIM OF STUDY

Urinary tract infections (UTIs) are among the most common infections affecting individuals of different ages worldwide. Antimicrobial agents are usually the first-line treatment for UTIs, and the use of the prescribed antibiotic is escalating, resulting in increased rates of bacterial resistance and UTI recurrence. The current study aimed to identify the causative bacteria in Jordan, to explore their resistance pattern to antibiotics and to describe drug-related problems (DRPs) associated with UTI management.

METHODS

This prospective, descriptive study was conducted in two major health institutions in two cities in Jordan over a period of six months. The study population included inpatients and outpatients diagnosed with UTIs. Patients' data were collected directly from patients using data collection sheet and from patients' charts.

RESULTS

A total of 273 patients were included, of whom 56.4% were women. Urine cultures were obtained from 81% of the patients. Escherichia coli was the most common causative pathogen (50.6%), followed by Klebsiella pneumonia (10.8%). Extended spectrum beta-lactamase (ESBL) producing E. coli was the most commonly detected organism across all types of UTIs. Ceftriaxone and imipenem/cilastatin were most commonly administered to hospitalised patients, whilst ciprofloxacin and co-triamzaxole were the most commonly prescribed in outpatient clinics. The susceptibility results for parenteral antibiotics showed high rates of resistance to cefazolin and ticarcillin. Additionally, high rates of resistance to fluoroquinolones were identified. Further, several DRPs were identified. High rates of resistance to commonly prescribed antibiotics were detected. DRPs (ie, inappropriate antibiotic dosage, unnecessary antibiotic prescribing, inappropriate duration of therapy and prescribing of ineffective antibiotics) were relatively common.

CONCLUSION

The present study highlights the need for clinical pharmacists to manage the high level of drug related problems by providing updated information about proper drug selection, rational drug use and patient education and counselling.

Associations of delirium with urinary tract infections and asymptomatic bacteriuria in adults aged 65 and older: A systematic review and meta-analysis

Objective

To determine the associations of delirium with urinary tract infection (UTI) and asymptomatic bacteriuria (AB) in individuals aged 65 and older.

Methods

The protocol for this systematic review and meta‐analysis was published on PROSPERO (CRD42020164341). Electronic databases were searched for relevant studies, professional associations and experts in the field were additionally contacted. Studies with control groups reporting associations between delirium and UTI as well as delirium and AB in older adults were included. The random effects model meta‐analysis was conducted using odds ratios (ORs) with 95% confidence intervals (CIs) as effect size measures. The Newcastle‐Ottawa scale was used to rate the studies' quality. Heterogeneity was assessed using the Q and I² tests. The effects of potential moderators were investigated by both subgroup and meta‐regression analyses. The risk of publication bias was evaluated using the funnel plot and Egger's test.

Results

Twenty nine relevant studies (16,618 participants) examining the association between delirium and UTI in older adults were identified. The association between delirium and UTI was found to be significant (OR 2.67; 95% CI 2.12–3.36; p < 0.001) and persisted regardless of potential confounders. The association between delirium and AB in older adults in the only eligible study found (192 participants) was insignificant (OR 1.62; 95% CI 0.57–4.65; p = 0.37). All included studies were of moderate quality.

Conclusion

The results of this study support the association between delirium and UTI in older adults. Insufficient evidence was found to conclude on an association between delirium and AB in this age group. These findings are limited due to the moderate quality of the included studies and a lack of available research on the association between delirium and AB. Future studies should use the highest quality approaches for defining both delirium and UTI and consider AB in their investigations.

Trends in prevalence of extended-spectrum beta-lactamase-producing Escherichia coli isolated from patients with community- and healthcare-associated bacteriuria: results from 2014 to 2020 in an urban safety-net healthcare system

BACKGROUND

The prevalence of infections caused by extended-spectrum beta-lactamase producing Escherichia coli (ESBL-E. coli) is increasing worldwide, but the setting in which this increase is occurring is not well defined. We compared trends and risk factors for ESBL-E. coli bacteriuria in community vs healthcare settings.

METHODS

We collected electronic health record data on all patients with E. coli isolated from urine cultures in a safety-net public healthcare system from January 2014 to March 2020. All analyses were stratified by healthcare-onset/associated (bacteriuria diagnosed > 48 h after hospital admission or in an individual hospitalized in the past 90 days or in a skilled nursing facility resident, N = 1277) or community-onset bacteriuria (bacteriuria diagnosed < 48 h after hospital admission or in an individual seen in outpatient clinical settings without a hospitalization in the past 90 days, N = 7751). We estimated marginal trends from logistic regressions to evaluate annual change in prevalence of ESBL-E. coli bacteriuria among all bacteriuria. We evaluated risk factors using logistic regression models.

RESULTS

ESBL-E. coli prevalence increased in both community-onset (0.91% per year, 95% CI 0.56%, 1.26%) and healthcare-onset/associated (2.31% per year, CI 1.01%, 3.62%) bacteriuria. In multivariate analyses, age > 65 (RR 1.88, CI 1.17, 3.05), male gender (RR 2.12, CI 1.65, 2.73), and Latinx race/ethnicity (RR 1.52, CI 0.99, 2.33) were associated with community-onset ESBL-E. coli. Only male gender (RR 1.53, CI 1.03, 2.26) was associated with healthcare-onset/associated ESBL-E. coli.

CONCLUSIONS

ESBL-E. coli bacteriuria frequency increased at a faster rate in healthcare-associated settings than in the community between 2014 and 2020. Male gender was associated with ESBL-E. coli bacteriuria in both settings, but additional risks-age > 65 and Latinx race/ethnicity-were observed only in the community.

Spatial, Ecologic, and Clinical Epidemiology of Community-Onset, Ceftriaxone-Resistant Enterobacteriaceae, Cook County, Illinois, USA

We performed a spatial and mixed ecologic study of community-onset Enterobacteriaceae isolates collected from a public healthcare system in Cook County, Illinois, USA. Individual-level data were collected from the electronic medical record and census tract–level data from the US Census Bureau. Associations between individual- and population-level characteristics and presence of ceftriaxone resistance were determined by logistic regression analysis. Spatial analysis confirmed nonrandom distribution of ceftriaxone resistance across census tracts, which was associated with higher percentages of Hispanic, foreign-born, and uninsured residents. Individual-level analysis showed that ceftriaxone resistance was associated with male sex, an age range of 35–85 years, race or ethnicity other than non-Hispanic Black, inpatient encounter, and percentage of foreign-born residents in the census tract of isolate provenance. Our findings suggest that the likelihood of community-onset ceftriaxone resistance in Enterobacteriaceae is influenced by geographic and population-level variables. The development of effective mitigation strategies might depend on better accounting for these factors.

Clinical and Molecular Findings of Infections Caused by Extended-Spectrum β-Lactamase-Producing Enterobacterales in Patients with Solid Tumors: A Single-Center Study

Infectious complications caused by multidrug-resistant bacteria are a serious clinical and therapeutic problem. Our study aimed to analyze the genetic characteristics of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) that cause multidrug-resistant infections in patients with solid tumors. Identification of ESBL-encoding genes was performed by polymerase chain reaction (PCR) and sequencing. The clonal relationship of the isolates was evaluated by pulsed-field gel electrophoresis. Multilocus sequence typing (MLST) was carried out for selected Escherichia coli and Klebsiella pneumoniae isolates. All E. coli strains were classified into phylogenetic groups using the PCR-based approach. There were 735 patients with clinical symptoms of infections tested, of which 44 (6.0%) were positive for ESBL-E on genotypic testing. The most frequent organism was E. coli (n = 24, 54.5%), followed by K. pneumoniae (n = 13, 29.5%), Proteus mirabilis (n = 3, 6.8%), Enterobacter cloacae cplx (n = 2, 4.5%), and Klebsiella oxytoca (n = 2, 4.5%). Overall, 31 (70.5%) of the ESBL-E isolates carried only bla_CTX-M-1-like genes, and the genes were found to be bla_CTX-M-15 (n = 30, 68.2%) or bla_CTX-M-3 (n = 1, 2.3%). Eleven strains (25%) had bla_CTX-M-9-like genes, mostly bla_CTX-M-27 (n = 10, 22.7%) and unique bla_CTX-M-65 (n = 1, 2.3%). One isolate possessed both bla_CTX-M-15 and bla_CTX-M-27 genes, and another one produced TEM-12 ESBL. MLST analysis revealed E. coli sequence type (ST) 131 and ST361, and K. pneumoniae ST16, ST307, and ST437. Among E. coli isolates, the B2 phylogenetic group was predominant. Most of the strains showed resistance to third-generation cephalosporins and fluoroquinolones, and susceptibility to aminoglycosides and carbapenems. Patients with solid cancer and ESBL-E infections require special management since they are a population with a high threat of antibiotic-resistant infections. Carbapenems and aminoglycosides remain active antibiotics against these infections.

A dual-caged resorufin probe for rapid screening of infections resistant to lactam antibiotics

The alarming increase of antimicrobial resistance urges rapid diagnosis and pathogen specific infection management. This work reports a rapid screening assay for pathogenic bacteria resistant to lactam antibiotics. We designed a fluorogenic N-cephalosporin caged 3,7-diesterphenoxazine probe CDA that requires sequential activations to become fluorescent resorufin. A series of studies with recombinant β-lactamases and clinically prevalent pathogens including Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Serratia marcescens demonstrated that CDA possessed superior sensitivity in reporting the activity of β-lactamases including cephalosporinases and carbapenemases. After a simple filtration, lactam-resistant bacteria in urine samples could be detected at 103 colony-forming units per milliliter within 2 hours.

High Prevalence of Extended-Spectrum Beta-Lactamases in Escherichia coli Strains Collected From Strictly Defined Community-Acquired Urinary Tract Infections in Adults in China: A Multicenter Prospective Clinical Microbiological and Molecular Study

Objective

The objective of the study was to investigate the antimicrobial susceptibility and extended-spectrum beta-lactamase (ESBL) positive rates of Escherichia coli from community-acquired urinary tract infections (CA-UTIs) in Chinese hospitals.

Materials and Methods

A total of 809 E. coli isolates from CA-UTIs in 10 hospitals (5 tertiary and 5 secondary hospitals) from different regions in China were collected during the period 2016–2017 according to the strict inclusion criteria. Antimicrobial susceptibility testing was carried out by standard broth microdilution method. Isolates were categorized as ESBL-positive, ESBL-negative, and ESBL-uncertain groups according to the CLSI recommended phenotypic screening method. ESBL and AmpC genes were amplified and sequenced on ESBL-positive and ESBL-uncertain isolates.

Results

The antimicrobial agents with susceptibility rates of greater than 95% included imipenem (99.9%), colistin (99.6%), ertapenem (98.9%), amikacin (98.3%), cefmetazole (97.9%), nitrofurantoin (96%), and fosfomycin (95.4%). However, susceptibilities to cephalosporins (varying from 58.6% to 74.9%) and levofloxacin (48.8%) were relatively low. In the phenotypic detection of ESBLs, ESBL-positive isolates made up 38.07% of E. coli strains isolated from CA-UTIs, while 2.97% were ESBL-uncertain. Antimicrobial susceptibilities of imipenem, cefmetazole, colistin, ertapenem, amikacin, and nitrofurantoin against ESBL-producing E. coli strains were greater than 90%. The percentage of ESBL-producing strains was higher in male (53.6%) than in female patients (35.2%) (p < 0.001). CTX-M-14 (31.8%) was the major CTX-M variant in the ESBL-producing E. coli, followed by CTX-M-55 (23.4%), CTX-M-15 (17.5%), and CTX-M-27 (13.3%). The prevalence of carbapenem-resistant E. coli among CA-UTI isolates was 0.25% (2/809).

Conclusion

Our study indicated high prevalence of ESBL in E. coli strains from strictly defined community-acquired urinary tract infections in adults in China. Imipenem, colistin, ertapenem, amikacin, and nitrofurantoin were the most active antimicrobials against ESBL-positive E. coli isolates. bla_CTX–M–14 is the predominant esbl gene in ESBL-producing and ESBL-uncertain strains. Our study indicated that the use of cephalosporins and fluoroquinolone needs to be restricted for empirical treatment of CA-UTIs in China.

Effectiveness and safety of an institutional aminoglycoside-based regimen as empirical treatment of patients with pyelonephritis

OBJECTIVES

To determine clinical outcomes associated with aminoglycosides versus other antimicrobial agents as empirical treatment of hospitalized patients with pyelonephritis.

PATIENTS AND METHODS

An institutional programme promoting aminoglycosides as empirical treatment of pyelonephritis was implemented in 2016. We reviewed the hospital records of patients with pyelonephritis from January 2017 to April 2019. The primary outcome was death within 30 days of index culture. Initial treatment with aminoglycoside-based regimens was compared with non-aminoglycoside antibiotics. Propensity score matching was performed to adjust for between-group differences in baseline covariates.

RESULTS

The study cohort included 2026 patients, 715 treated with aminoglycosides and 1311 treated with non-aminoglycoside drugs (ceftriaxone, n = 774; piperacillin/tazobactam, n = 179; carbapenems, n = 161; and fluoroquinolones, n = 133); 589 patients (29%) had bloodstream infections. Treatment with aminoglycosides was associated with a higher likelihood of in vitro activity against clinical isolates (OR = 2.0; P < 0.001). Death at 30 days occurred in 55 (7.6%) versus 145 (11%) patients treated with aminoglycosides and non-aminoglycoside drugs, respectively (adjusted HR = 0.78; P = 0.013). Aminoglycosides were either superior or similar to comparator drugs in all patient subgroups, stratified according to age, glomerular filtration rate, bacteraemia, haemodynamic shock and infection with third-generation cephalosporin-resistant Enterobacteriaceae. The incidence of acute kidney injury was similar for aminoglycosides and comparators (2.5% versus 2.9%, respectively; P = 0.6).

CONCLUSIONS

Within the context of an institutional programme, initial empirical treatment of pyelonephritis with aminoglycosides was associated with higher rates of in vitro activity and lower overall mortality compared with non-aminoglycoside drugs, without excess nephrotoxicity.

Antimicrobial Resistance Trends in Urine Escherichia coli Isolates From Adult and Adolescent Females in the United States From 2011-2019: Rising ESBL Strains and Impact on Patient Management

Background

Uncomplicated urinary tract infection (uUTI) is predominantly caused by Escherichia coli, which has increasing antimicrobial resistance (AMR) at the United States (US)-community level. As uUTI is often treated empirically, assessing AMR is challenging, and there are limited contemporary data characterizing period prevalence in the US.

Methods

This was a retrospective study of AMR using Becton, Dickinson and Company Insights Research Database (Franklin Lakes, New Jersey, US) data collected 2011–2019. Thirty-day, nonduplicate Escherichia coli urine isolates from US female outpatients (aged ≥12 years) were included. Isolates were evaluated for nonsusceptibility (intermediate/resistant) to trimethoprim-sulfamethoxazole, fluoroquinolones, or nitrofurantoin, and assessed for extended-spectrum β-lactamase production (ESBL+) and for ≥2 or ≥3 drug-resistance phenotypes. Generalized estimating equations were used to model AMR trends over time and by US census region.

Results

Among 1 513 882 E. coli isolates, the overall prevalence of isolates nonsusceptible to trimethoprim-sulfamethoxazole, fluoroquinolones, and nitrofurantoin was 25.4%, 21.1%, and 3.8%, respectively. Among the isolates, 6.4% were ESBL+, 14.4% had ≥2 drug-resistance phenotypes, and 3.8% had ≥3. Modeling demonstrated a relative average yearly increase of 7.7% (95% confidence interval [CI], 7.2–8.2%) for ESBL+ isolates and 2.7% (95% CI, 2.2–3.2%) for ≥3 drug-phenotypes (both P < .0001). Modeling also demonstrated significant variation in AMR prevalence between US census regions (P < .001).

Conclusions

Period prevalence of AMR among US outpatient urine-isolated E. coli was high, and for multidrug-resistance phenotypes increased during the study period with significant variation between census regions. Knowledge of regional AMR rates helps inform empiric treatment of community-onset uUTI and highlights the AMR burden to physicians.

Outcomes for Patients with Urinary Tract Infection After an Initial Intravenous Antibiotics Dose Before Emergency Department Discharge

INTRODUCTION

To investigate the effect of single-dose intravenous antibiotics before emergency department (ED) discharge on the outcomes of patients with urinary tract infections (UTIs).

METHODS

This is a retrospective study conducted at the EDs of three medical centers. Patients aged over 18 years who presented to the ED with UTI and were discharged without admission between January 1, 2016 and December 31, 2017 were evaluated. The study group received a single dose of effective intravenous antibiotics on the basis of urine culture during the index ED visit following oral antibiotics, while the comparison group received oral antibiotics only. The primary outcomes were ED revisit within 72 h and admission following the return visit.

RESULTS

A total of 8168 patients were included. Of these, 20.9% received intravenous antibiotics before ED discharge. Patients who received effective intravenous antibiotics before ED discharge were associated with less than 72-h ED revisit (adjusted odds ratio [OR] 0.791, 95% confidence interval [CI] 0.640-0.979]), but not decreased admission following the return visit (adjusted OR 0.921, 95% CI [0.731-1.153]). In subgroup analysis, parenteral antibiotic use during the index ED visit was associated with decreased admission following ED revisit in patients who presented with fever (adjusted OR 0.605; 95% CI 0.443-0.932).

CONCLUSION

For patients with UTI and clinically well to be discharged from the ED, a single dose of effective intravenous antibiotics before ED discharge was associated with decreased 72-h ED revisit. In patients with febrile UTI, initial intravenous antibiotics were associated with decreased revisit leading to admissions.