Application of Fluoroquinolone Resistance Score in Management of Complicated Urinary Tract Infections

Re-evaluating the suitability of using fluoroquinolones in the treatment of infections in the context of FQ consumption and correlating changes to microorganism resistance levels in EU/EEA countries between 2016 and 2021

The aim of this study was to re-evaluate fluoroquinolone (FQ) use in treatment by analyzing the consumption of FQ and the resistance levels of selected Gram‑negative bacilli, as well as Neisseria gonorrhoeae and Mycobacterium tuberculosis complex in EU/EEA countries and in Poland between 2016 and 2021. Data from ECDC surveillance systems EARS-Net, Euro-GASP, and the European Tuberculosis Surveillance Network were included in the description of pathogen resistance. And the ESAC-Net project for determining FQ consumption. In over half of the EU/EEA countries, the consumption of fluoroquinolones decreased in both the community sector and the hospital sector between 2016 and 2021. The prevalence of FQ-R Escherichia coli, Klebsiella pneumoniae, Acinetobacter spp., Mycobacterium tuberculosis complex, and Neisseria gonorrhoeae exceeded 20%. The prevalence of fluoroquinolone-resistant (FQ-R) Pseudomonas aeruginosa in EU/EEA countries was less than 20% except for 2017. In most EU/EEA countries, the use of FQ has reduced in last years, except for countries like Poland where FQ were an overused group of antibiotics in the treatment of various types of infections. Fluoroquinolones, as life-saving antibiotics in severe infections, should be withdrawn from empirical treatment in Poland and in countries with a high prevalence of FQ-R microorganisms.

Application of Precision Medicine Concepts in Ambulatory Antibiotic Management of Acute Pyelonephritis

Acute pyelonephritis (APN) is a relatively common community-acquired infection, particularly in women. The early appropriate antibiotic treatment of this potentially life-threatening infection is associated with improved outcomes. The international management guidelines for complicated urinary tract infections and APN recommend using oral antibiotics with <10% resistance among urinary pathogens. However, increasing antibiotic resistance rates among Escherichia coli and other Enterobacterales to fluoroquinolones, trimethoprim-sulfamethoxazole (TMP-SMX), and beta-lactams has left patients without reliable oral antibiotic treatment options for APN. This narrative review proposes using precision medicine concepts to improve empirical antibiotic therapy for APN in ambulatory settings. Whereas resistance rates to a particular antibiotic class may exceed 10% at the population-based level, the predicted antibiotic resistance rates based on patient-specific risk factors fall under 10% in many patients with APN on the individual level. The utilization of clinical tools for the prediction of fluoroquinolones, TMP-SMX, and third-generation cephalosporin resistance improves the ambulatory antibiotic management of APN. It may also reduce the need to switch antibiotic therapy later based on the in vitro antibiotic susceptibility testing results of bacterial isolates in urinary cultures. This approach may mitigate the burden of increasing antibiotic resistance in the community by ensuring that the initial antibiotic prescribed has the highest likelihood of treating APN appropriately.

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.

Defining the Optimal Duration of Therapy for Hospitalized Patients With Complicated Urinary Tract Infections and Associated Bacteremia

BACKGROUND

Limited data are available to guide effective antibiotic durations for hospitalized patients with complicated urinary tract infections (cUTIs).

METHODS

We conducted an observational study of patients ≥18 years at 24 US hospitals to identify the optimal treatment duration for patients with cUTI. To increase the likelihood patients experienced true infection, eligibility was limited to those with associated bacteremia. Propensity scores were generated for an inverse probability of treatment weighted analysis. The primary outcome was recurrent infection with the same species ≤30 days of completing therapy.

RESULTS

1099 patients met eligibility criteria and received 7 (n = 265), 10 (n = 382), or 14 (n = 452) days of therapy. There was no difference in the odds of recurrent infection for patients receiving 10 days and those receiving 14 days of therapy (aOR: .99; 95% CI: .52-1.87). Increased odds of recurrence was observed in patients receiving 7 days versus 14 days of treatment (aOR: 2.54; 95% CI: 1.40-4.60). When limiting the 7-day versus 14-day analysis to the 627 patients who remained on intravenous beta-lactam therapy or were transitioned to highly bioavailable oral agents, differences in outcomes no longer persisted (aOR: .76; 95% CI: .38-1.52). Of 76 patients with recurrent infections, 2 (11%), 2 (10%), and 10 (36%) in the 7-, 10-, and 14-day groups, respectively, had drug-resistant infections (P = .10).

CONCLUSIONS

Seven days of antibiotics appears effective for hospitalized patients with cUTI when antibiotics with comparable intravenous and oral bioavailability are administered; 10 days may be needed for all other patients.

The time-varying association between previous antibiotic use and antibiotic resistance

OBJECTIVES

The objective of the study was to estimate how the time elapsed from previous antibiotic use is associated with antibiotic resistance.

METHODS

Data comprised electronic medical records of all patients in an Israeli hospital who had a positive bacterial culture from 2016 to 2019. These included susceptibility testing results and clinical and demographic data. Mixed-effects time-varying logistic models were fitted to estimate the association between the time elapsed since the last use of aminoglycosides and gentamicin resistance (n = 13 095), cephalosporins and ceftazidime resistance (n = 13 051), and fluoroquinolones and ciprofloxacin resistance (n = 15 364) while adjusting for multiple covariates.

RESULTS

For all examined antibiotics, previous antibiotic use had a statistically significant association with resistance (p < 0.001). These associations exhibited a clear decreasing pattern over time, which we present as a flexible function of time. Nonetheless, previous antibiotic use remained a significant risk factor for resistance for at least 180 days when the adjusted ORs were 1.94 (95% CI, 1.40-2.69), 1.33 (95% CI, 1.10-1.61), and 2.25 (95% CI, 1.49-3.41) for gentamicin, ceftazidime, and ciprofloxacin, respectively.

DISCUSSION

The association between prior antibiotic use and resistance decreases over time. Commonly used cut-offs for prior antibiotic use can either misclassify patients still at higher risk when too recent or provide a diluted estimate of the effects of antibiotic use on future resistance when too distant. Hence, prior antibiotic use should be considered a time-dependent risk factor for resistance in both epidemiological research and clinical practice.

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.

Antibiotic resistance of Escherichia coli urinary tract infections at a North Carolina community hospital: Comparison of rural and urban community type

OBJECTIVE

We aimed to identify differences in urinary E. coli resistance rates based on community type of patient residence (rural and urban).

METHODS

This cross-sectional study examined antibiotic resistance of E. coli isolates from 12,604 urine specimens at a North Carolina hospital between 2016 and 2018. Using multivariable logistic regression modeling, we investigated the association between resistance and community type, adjusting for patient age, gender, season, and setting of infection onset. Analyses were performed using SAS Version 9.3 (SAS Institute, Cary, NC) at alpha = 0.05.

RESULTS

Prevalence of resistance was highest for ampicillin (42.2%), ampicillin-sulbactam (24.7%), ciprofloxacin (21.8%), trimethoprim-sulfamethoxazole (SXT) (21.6%), and levofloxacin (21.4%). Rural compared to urban community type was significantly associated with resistance of E. coli urinary isolates to ciprofloxacin (adjusted odds ratio [aOR] = 1.29, 95% confidence interval [CI] = 1.16-1.43, P < .0001), levofloxacin (aOR = 1.28, 95% CI = 1.15-1.42, P < .0001), SXT (aOR = 1.15, 95% CI = 1.04-1.27, P = .01), and nitrofurantoin (aOR = 1.57, 95% CI = 1.13-2.17, P = .01).

CONCLUSIONS

Rural community type may influence urinary E. coli resistance to fluoroquinolones, SXT, and nitrofurantoin, indicating the need for antimicrobial stewardship interventions in medically underserved populations.

The Five Ds of Outpatient Antibiotic Stewardship for Urinary Tract Infections

Urinary tract infections (UTI) are one of the most common indications for antibiotic prescriptions in the outpatient setting. Given rising rates of antibiotic resistance among uropathogens, antibiotic stewardship is critically needed to improve outpatient antibiotic use, including in outpatient clinics (primary care and specialty clinics) and emergency departments. Outpatient clinics are in general a neglected practice area in antibiotic stewardship programs, yet most antibiotic use in the United States is in the outpatient setting. This article provides a comprehensive review of antibiotic stewardship strategies for outpatient UTI in the adult population, with a focus on the "five Ds" of stewardship for UTI, including right diagnosis, right drug, right dose, right duration, and de-escalation. Stewardship interventions that have shown success for improving prescribing for outpatient UTI are discussed, including diagnostic stewardship strategies, such as reflex urine cultures, computerized decision support systems, and modified reporting of urine culture results. Among the many challenges to achieving stewardship for UTI in the outpatient setting, some of the most important are diagnostic uncertainty, increasing antibiotic resistance, limitations of guidelines, and time constraints of stewardship personnel and front-line providers. This article presents a stewardship framework, built on current evidence and expert opinion, that clinicians can use to guide their own outpatient management of UTI.

Advances in novel antibiotics to treat multidrug-resistant gram-negative bacterial infections

Antimicrobial resistance is a growing threat to public health and an increasingly common problem for acute care physicians to confront. Several novel antibiotics have been approved in the past decade to combat these infections; however, physicians may be unfamiliar with how to appropriately utilize them. The purpose of this review is to evaluate novel antibiotics active against resistant gram-negative bacteria and highlight clinical information regarding their use in the acute care setting. This review focuses on novel antibiotics useful in the treatment of infections caused by resistant gram-negative organisms that may be seen in the acute care setting. These novel antibiotics include ceftolozane/tazobactam, ceftazidime/avibactam, meropenem/vaborbactam, imipenem/cilistatin/relebactam, cefiderocol, plazomicin, eravacycline, and omadacycline. Acute care physicians should be familiar with these novel antibiotics so they can utilize them appropriately.

Virulence Genes Profile and Antimicrobial Susceptibility of Community-Acquired Bacterial Urinary Tract Infections in a Brazilian Hospital

Urinary tract infections (UTI) are one of the most common diseases worldwide and Escherichia coli is the most common causative bacteria. Empirical treatment is challenging due to antimicrobial or multidrug-resistance. The aims of this study were to determine the uropathogens and their antimicrobial susceptibility profile, as well as to identify the phylogroups and virulence genes of E. coli strains, associated with community-acquired UTI in outpatients admitted at a Brazilian Hospital in southeast Brazil. In total, 47 bacterial strains were isolated from 47 patients, 44 women and 2 men (no gender record from one patient). The age of the patients whose urine culture were positive varied from 0 (less than one month) to 104 years. Most of the isolates were E. coli (41/47), followed by Klebsiella pneumoniae (2/47), Klebsiella variicola/Klebsiella aerogenes (1/47), Pseudomonas aeruginosa (1/47), Proteus mirabilis (1/47), and Citrobacter koseri (1/47). Most E. coli strains were classified as phylogroup B2 (15/41 = 36.59%) and B1 (12/41 = 29.27%) and the most common virulence genes among E. coli strains were fimH (31/41 = 75.61%), iutA (21/41 = 51.22%), and tratT (16/41 = 39.02%). Among the E. coli strains, 59% were multidrug-resistance and strains that were ampicillin, sulfamethoxazole/trimethoprim, or tetracycline-resistant exhibited more chance to be multidrug-resistance, with an odds ratio of 100.00 [95% confidence interval (CI) 9.44-1059.26], 22.50 (95% CI 3.95-128.30), and 12.83 (95% CI 2.68-61.45), respectively. Our results showed that E. coli was the main etiological agent identified and demonstrated high frequency of multidrug-resistance and virulence factors in bacterial strains isolated from UTIs.

Fluoroquinolone resistant bacterial isolates from the urinary tract among patients attending hospitals in Bushenyi District, Uganda

Introduction

bacterial resistance to fluoroquinolones is on the rise globally, bacteria causing urinary tract infections (UTIs) are no exception to this fact. Judicious use of the current antibiotics by clinicians is therefore deemed necessary to combat development of resistance. This study determined fluoroquinolone resistant profiles, multiple antibiotic resistance indices (MARI), factors associated with fluoroquinolone resistance and their strength among patients attending hospitals in Bushenyi District, Uganda.

Methods

this was a cross-sectional study in which a total of 86 bacterial uropathogens isolated previously by standard microbiological methods were subjected to antibiotic susceptibility testing using Kirby Bauer disk diffusion method. Data for factors suspected to be associated with fluoroquinolone resistant UTI were obtained by use of questionnaires.

Results

the most resisted fluoroquinolone was ofloxacin with 29/83 (34.9%), followed by moxifloxacin 27/83 (32.5%), levofloxacin 24/86 (27.9%) and ciprofloxacin 23/86 (26.7%). The bacterial uropathogens that exhibited the highest frequency of fluoroquinolone resistant strains were P. mirabilis with 2/3 (66.7%) and E. faecalis with 2/3 (66.7%), followed by E. coli 19/36 (52.8%), S. aureus 13/27 (48.1%), K. oxytoca 2/6 (33.3%), K. pneumoniae 2/10 (20.0%) and P. vulgaris 0/1 (0.0%). All the bacterial uropathogens tested showed MARI of ≥ 0.2. Hospitalization, history of fluoroquinolones use in the last 12 months and wrong prescription of antibiotics were found to bear statistically significant relationships (p < 0.05) with fluoroquinolone resistant UTI.

Conclusion

antibiotic susceptibility testing of the first generation quinolones such as nalidixic acid in hospitalized patients, patients with history of fluoroquinolones' use in the last 12 months and wrong prescription of antibiotics should be adopted to avoid fluoroquinolone abuse. For empiric treatment of UTIs in Bushenyi District, ciprofloxacin still remains the first line of choice among the fluoroquinolone class of antibiotics.

Prediction of trimethoprim/sulfamethoxazole resistance in community-onset urinary tract infections

OBJECTIVES

This study aimed to predict trimethoprim/sulfamethoxazole (SXT) resistance in patients with community-onset urinary tract infection (UTI) due to Enterobacteriaceae based on patient-specific risk factors.

METHODS

This was a retrospective case-control study in Prisma Health facilities in central South Carolina, USA, including three community hospitals, affiliated emergency departments and ambulatory clinics, including adult patients with community-onset UTI due to Enterobacteriaceae (1 April 2015 to 29 February 2016). Multivariate logistic regression was used to examine risk factors for SXT resistance.

RESULTS

Among 351 unique patients with community-onset UTI, 71 (20.2%) had SXT-resistant Enterobacteriaceae urinary isolates. Overall, median age was 64 years and 252 (71.8%) were female. A multivariate model identified prior urinary infection/colonisation with SXT-resistant Enterobacteriaceae (OR=8.58, 95% CI 3.92-18.81; P<0.001) and SXT use within past 12 months (OR=2.58, 95% CI 1.13-5.89; P=0.02) as predictors of SXT resistance among urinary isolates. Most patients with UTI (285; 81.2%) had no risk factors for SXT resistance. SXT resistance rates increased from 13% in the absence of risk factors to 31% in patients with prior SXT use, 66% in those with prior urinary infection/colonisation with SXT-resistant Enterobacteriaceae and 73% in the presence of both risk factors.

CONCLUSION

SXT resistance in Enterobacteriaceae urinary isolates may be predicted based on prior urine culture results and SXT use within the previous year. Utilisation of a patient-specific antibiogram may allow empirical SXT use in patients with community-onset UTI in the absence of risk factors for resistance.

Prevalence of quinolone-resistant uropathogenic Escherichia coli in a tertiary care hospital in south Iran

Background: Quinolones are a family of synthetic antimicrobial agents with a broad antibacterial activity commonly used as a suitable therapy in patients with urinary tract infection (UTI). In the present study, we aimed to evaluate the prevalence of quinolones resistance and the presence of plasmid-mediated quinolone resistance (PMQR) genes among Escherichia coli isolates.

Methods

This study was performed on a collection of 121 E. coli isolates derived from patients with UTI. Antimicrobial susceptibility to nalidixic acid, ciprofloxacin, levofloxacin, norfloxacin, and ofloxacin was specified by the disk diffusion method. The presence of PMQR genes was determined by PCR method.

Results

Antibiotic susceptibility results showed that the highest and lowest resistance rates were against nalidixic acid (71.9%) and norfloxacin (44.6%), respectively. The molecular results showed that 40 (33.1%) and 15 (12.4%) of the isolates were positive for qnrS and qnrB genes, respectively. Meanwhile, 5 (4.1%) of the isolates were found positive for both genes, while none were found to be positive for qnrA gene. There was no significant association between the presence of qnr genes and higher antibiotic resistance.

Conclusion

We found high levels of quinolones resistance (more than 40%) among E. coli strains isolated from patients with UTIs in the south of Iran. We further report the prevalence of PMQR genes among uropathogenic E. coli; however, it seems that these genes are not the main components of quinolone resistance in our region.