Choice of Empirical Antibiotic Therapy and Adverse Outcomes in Older Adults With Suspected Urinary Tract Infection: Cohort Study

Assessing the impact of discordant antibiotic treatment on adverse outcomes in community-onset UTI: a retrospective cohort study

OBJECTIVES

To investigate the risk of adverse outcomes following discordant antibiotic treatment (urinary organism resistant) for culture-confirmed community-onset lower urinary tract infection (UTI).

METHODS

Cohort study using routinely collected linked primary care, secondary care and microbiology data from patients with culture-confirmed community-onset lower UTI (COLUTI). Antibiotic treatment within ±3 days was considered concordant if the urinary organism was sensitive and discordant if resistant.The primary outcome was the proportion of patients experiencing urinary infection-related hospital admission (UHA) within 30 days. Secondary outcomes were the proportion of patients experiencing reconsultation within 30 days, and the odds of UHA and reconsultation following discordant treatment, adjusting for sex, age, risk factors for complicated UTI, previous antibiotic treatment, recurrent UTI and comorbidities.

RESULTS

A total of 11 963 UTI episodes in 8324 patients were included, and 1686 episodes (14.1%, 95% CI 13.5%-14.7%) were discordant. UHA occurred in 212/10 277 concordant episodes (2.1%, 95% CI 1.8%-2.4%) and 88/1686 discordant episodes (5.2%, 95% CI 4.2%-6.4%). Reconsultation occurred in 3961 concordant (38.5%, 95% CI 37.6%-39.5%) and 1472 discordant episodes (87.3%, 95% CI 85.6%-88.8%). Discordant treatment compared with concordant was associated with increased odds of UHA (adjusted OR 2.31, 95% CI 1.77-3.0, P < 0.001) and reconsultation (adjusted OR 11.25, 95% CI 9.66-13.11, P < 0.001) on multivariable analysis. Chronic kidney disease and diabetes mellitus were also independently associated with increased odds of UHA.

CONCLUSIONS

One in seven COLUTI episodes in primary care were treated with discordant antibiotics. In higher risk patients requiring urine culture, empirical antibiotic choice optimization could meaningfully reduce adverse outcomes.

Clinical utility of prior positive cultures to optimize empiric antibiotic therapy selection: A cross-sectional analysis

Background

Despite reduced infectious disease mortality and improved survival, infectious diseases continue to pose health threats due to their contagiousness, societal harm, and morbidity. Empiric antibiotic therapy, often prescribed without knowledge of the causative pathogen, faces challenges from rising antibiotic resistance. This study explores the potential of prior positive culture results to guide empiric antibiotic therapy.

Methods

Data from King Abdullah University Hospital (Jan 2014-Dec 2019) included adult patients with recurrent bacterial infections (pneumonia, sepsis, UTIs, wounds). Excluded cases included: mixed infections, transfers, <14 days or >12 months between episodes. The study compared bacterial growth and sensitivity patterns between previous and recent cultures.

Results

The study included 970 episodes from 650 patients, mainly UTIs (60.3%) and gram-negative bacteria (77.9%). The study found that (65.1%) of culture pairs matched. Empirical therapy was accurate in (71.8%) of cases. Further, accuracy of selected empiric antibiotic therapy was significantly predicted (p ​< ​0.001) by: type of infection, type of antibiotics, and concordance with prior microbiologic data. Multivariate logistic analysis showed blood culture as less predictive of pending identity (OR: 0.234, P ​< ​0.001) compared to urine culture; and prior affirmed gram negative bacterial culture was less predictive (OR: 0.606, P ​= ​0.021) compared to gram positive bacterial culture.

Conclusion

This study underscores the potential of prior positive culture results in guiding empiric antibiotic therapy, enhancing accuracy and identity agreement. Future research should explore this approach in different infection contexts and across multiple centers. Reducing the indiscriminate use of broad-spectrum antibiotics is essential to combat antibiotic resistance.

Clinical Efficacy and Cost Analysis of Antibiotics for Treatment of Uncomplicated Urinary Tract Infections in the Emergency Department of a Tertiary Hospital in Saudi Arabia

Purpose

Uncomplicated urinary tract infections (uUTIs) are one of the main reasons for emergency department (ED) visits. Many antibiotics can be used for uUTI treatment. Currently, no data concerning uUTIs and cost-effectiveness have been reported in Saudi Arabia. This study aimed to investigate antibiotic and cost-effectiveness of beta-lactams, fluoroquinolones, and nitrofurantoin as first-line uUTI treatment.

Patients and Methods

This study was a retrospective cohort based on a five-arm comparative outcome analysis. A cost-effectiveness analysis and comparative group of uUTI treatments in the ED at King Abdulaziz Medical City (KAMC) in Saudi Arabia over a three-month follow-up period was done. The patient group consisted of those presenting to the ED with uUTIs who were treated initially with one of five antibiotics: (1) amoxicillin/clavulanic acid, (2) cefuroxime, (3) ciprofloxacin, (4) nitrofurantoin, or (5) norfloxacin. The main outcomes were effectiveness in terms of cure rates, symptom-free days (SFDs), and estimations of cost-effectiveness among this group.

Results

A total of 865 adult patients who presented with uUTIs were enrolled. Most patients (89.5%) completely recovered, whereas 10.5% of patients were readmitted to the ED with recurrent infections. Effectiveness in terms of the highest cure rate was observed with nitrofurantoin and amoxicillin/clavulanic acid (93.2% and 92.2%, respectively) followed by norfloxacin, cefuroxime, and ciprofloxacin; no significant differences in cure rates were found among these antibiotics. Antibiotic effectiveness in terms of SFDs showed that nitrofurantoin produced the longest SFD period (76 days) followed by amoxicillin/clavulanic acid (69 days). A cost-effectiveness analysis in terms of uUTI cure rates and number of SFDs indicated that nitrofurantoin presented the highest cost-effectiveness followed by amoxicillin/clavulanic acid, norfloxacin, ciprofloxacin, and cefuroxime.

Conclusion

A comparison of five antibiotics for uUTI treatment did not yield clinically significant differences in cure rates. Nitrofurantoin was more cost-effective than the other antibiotics.

Risk of antimicrobial-associated organ injury among the older adults: a systematic review and meta-analysis

Background

Older adults (aged 65 years and above) constitute the fastest growing population cohort in the western world. There is increasing evidence that the burden of infections disproportionately affects older adults, and hence this vulnerable population is frequently exposed to antimicrobials. There is currently no systematic review summarising the evidence for organ injury risk among older adults following antimicrobial exposure. This systematic review and meta-analysis examined the relationship between antimicrobial exposure and organ injury in older adults.

Methodology

We searched for original research articles in PubMed, Embase.com, Web of Science core collection, Web of Science BIOSIS citation index, Scopus, Cochrane Central Register of Controlled Trials, ProQuest, and PsycINFO databases, using key words in titles and abstracts, and using MeSH terms. We searched for all available articles up to 31 May 2021. After removing duplicates, articles were screened for inclusion into or exclusion from the study by two reviewers. The Newcastle-Ottawa scale was used to assess the risk of bias for cohort and case-control studies. We explored the heterogeneity of the included studies using the Q test and I² test and the publication bias using the funnel plot and Egger’s test. The meta-analyses were performed using the OpenMetaAnalyst software.

Results

The overall absolute risks of acute kidney injury among older adults prescribed aminoglycosides, glycopeptides, and macrolides were 15.1% (95% CI: 12.8–17.3), 19.1% (95% CI: 15.4–22.7), and 0.3% (95% CI: 0.3–0.3), respectively. Only 3 studies reported antimicrobial associated drug-induced liver injury. Studies reporting on the association of organ injury and antimicrobial exposure by age or duration of treatment were too few to meta-analyse. The funnel plot and Egger’s tests did not indicate evidence of publication bias.

Conclusion

Older adults have a significantly higher risk of sustaining acute kidney injury when compared to the general adult population. Older adults prescribed aminoglycosides have a similar risk of acute kidney injury to the general adult population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02512-3.

US-Focused Conceptual Health Care Decision-Analytic Models Examining the Value of Pivmecillinam Relative to Current Standard-of-Care Agents Among Adult Patients With Uncomplicated Urinary Tract Infections due to Enterobacterales

Background

Pivmecillinam is approved for the treatment of adults with uncomplicated urinary tract infection (uUTI) in Canada and Europe and is pending United States (US) Food and Drug Administration submission for consideration for approval. US-focused health care decision-analytics were developed to define the value of an agent like pivmecillinam relative to current standard-of-care (SOC) agents among adult patients with Enterobacterales uUTIs based on its improved microbiologic activity against common Enterobacterales.

Methods

The model population was 100 theoretical adult outpatients with Enterobacterales uUTIs under 4 different uUTI first-line empiric treatment scenarios (ie, pivmecillinam, nitrofurantoin, trimethoprim-sulfamethoxazole [SXT], or fluoroquinolones). The total mean uUTI-related 30-day costs, including inappropriate treatment costs, were calculated for each regimen. The range of pivmecillinam regimen costs that conferred cost savings relative to the current SOC agents based on its potentially improved microbiologic activity against common Enterobacterales was determined.

Results

The 30-day uUTI-related costs associated with nitrofurantoin, SXT, and fluoroquinolones were $655.61, $687.57, and $659.69, respectively. The pivmecillinam neutral regimen cost thresholds that resulted in the same uUTI-related 30-day per-patient costs for nitrofurantoin, SXT, and fluoroquinolones were $83.50, $115.45, and $87.58, respectively. The overall antimicrobial susceptibility improvement required with pivmecillinam fixed at $200/regimen, for it to be cost savings relative to SOC agents, was 28%.

Conclusions

The analyses suggests that an agent like pivmecillinam, if approved in the US, has the potential to reduce the economic burden associated with inappropriate treatment of adult outpatients with uUTIs, especially in patients at high risk for an Enterobacterales uUTI that is resistant to SOC agents.

Antimicrobial pharmacokinetics and preclinical in vitro models to support optimized treatment approaches for uncomplicated lower urinary tract infections

INTRODUCTION

Urinary tract infections (UTIs) are extremely common. Millions of people, particularly healthy women, are affected worldwide every year. One-in-two women will have a recurrence within 12-months of an initial UTI. Inadequate treatment risks worsening infection leading to acute pyelonephritis, bacteremia and sepsis. In an era of increasing antimicrobial resistance, it is critical to provide optimized antimicrobial treatment.

AREAS COVERED

Literature was searched using PubMed and Google Scholar (up to 06/2020), examining the etiology, diagnosis and oral antimicrobial therapy for uncomplicated UTIs, with emphasis on urinary antimicrobial pharmacokinetics (PK) and the application of dynamic in vitro models for the pharmacodynamic (PD) profiling of pathogen response.

EXPERT OPINION

The majority of antimicrobial agents included in international guidelines were developed decades ago without well-described dose-response relationships. Microbiology laboratories still apply standard diagnostic methodology that has essentially remained unchanged for decades. Furthermore, it is uncertain how relevant standard in vitro susceptibility is for predicting antimicrobial efficacy in urine. In order to optimize UTI treatments, clinicians must exploit the urine-specific PK of antimicrobial agents. Dynamic in vitro models are valuable tools to examine the PK/PD and urodynamic variables associated with UTIs, while informing uropathogen susceptibility reporting, optimized dosing schedules, clinical trials and treatment guidelines.

Different antibiotic regimes in men diagnosed with lower urinary tract infection - a retrospective register-based study

OBJECTIVE

To compare the proportion of therapy failure, recurrence and complications within 30 days after consultation between men diagnosed with lower urinary tract infection (UTI) treated with narrow-spectrum antibiotics (nitrofurantoin or pivmecillinam) and broad-spectrum antibiotics (fluoroquinolones or trimethoprim or trimethoprim/sulfamethoxazole).

DESIGN

A retrospective cohort study based on data derived from electronic medical records between January 2012 and December 2015.

SETTING

Primary health care and hospital care in five different counties in Sweden. Patients: A total of 16,555 men aged between 18 and 79 years diagnosed with lower UTI.

MAIN OUTCOME MEASURES

Treatment with narrow-spectrum antibiotics was compared with broad-spectrum antibiotics regarding therapy failure, recurrence and complications within 30 days.

RESULTS

The median age of included men was 65 IQR (51-72) years. Narrow-spectrum antibiotics were prescribed in 8457 (40%) and broad-spectrum antibiotics in 12,667 (60%) cases, respectively. Therapy failure was registered in 192 (0.9%), recurrence in 1277 (6%) and complications in 121 (0.6%) cases. Therapy failure and recurrence were more common in patients treated with narrow-spectrum antibiotics and trimethoprim (p < 0.001), but no such difference could be detected regarding complications.

CONCLUSION

There was no difference in incidence of complications within 30 days between men treated with narrow- or broad-spectrum antibiotics. Patients prescribed broad-spectrum antibiotics had lower odds of reconsultation because of therapy failure and recurrence. From current data, treatment with narrow-spectrum antibiotics seems to be an optimal choice regarding preventing complications when treating men with lower UTI. KEY POINTS Complications such as pyelonephritis and sepsis are uncommon in men diagnosed with lower urinary tract infection treated with antibiotics. There was no difference in incidence of complications among men diagnosed with lower urinary tract infection treated with narrow- or broad-spectrum antibiotics. In spite of higher incidence of therapy failure and recurrence, treatment with narrow-spectrum antibiotics seems to be an optimal choice regarding preventing complications when treating men diagnosed with lower UTI.

Treatment of urinary tract infections in the era of antimicrobial resistance and new antimicrobial agents

Urinary tract infections (UTIs) caused by antibiotic-resistant Gram-negative bacteria are a growing concern due to limited treatment options. Knowledge of the common uropathogens in addition to local susceptibility patterns is essential in determining appropriate empiric antibiotic therapy of UTIs. The recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females is a 5-day course of nitrofurantoin, a 3-g single dose of fosfomycin tromethamine, or a 5-day course of pivmecillinam. High rates of resistance for trimethoprim-sulfamethoxazole and ciprofloxacin preclude their use as empiric treatment of UTIs in several communities, particularly if patients who were recently exposed to them or in patients who are at risk of infections with extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriales. Second-line options include oral cephalosporins such as cephalexin or cefixime, fluoroquinolones and β-lactams, such as amoxicillin-clavulanate. Current treatment options for UTIs due to AmpC- β -lactamase-producing Enterobacteriales include nitrofurantoin, fosfomycin, pivmecillinam, fluoroquinolones, cefepime, piperacillin-tazobactam and carbapenems. Treatment oral options for UTIs due to ESBLs-E coli include nitrofurantoin, fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin while pivmecillinam, fosfomycin, finafloxacin, and sitafloxacin are treatment oral options for ESBLs- Klebsiella pneumoniae. Parenteral treatment options for UTIs due to ESBLs-producing Enterobacteriales include piperacillin-tazobactam (for ESBL-E coli only), carbapenems including meropenem/vaborbactam, imipenem/cilastatin-relebactam, and sulopenem, ceftazidime-avibactam, ceftolozane-tazobactam, aminoglycosides including plazomicin, cefiderocol, fosfomycin, sitafloxacin, and finafloxacin. Ceftazidime-avibactam, meropenem/vaborbactam, imipenem/cilastatin-relebactam, colistin, fosfomycin, aztreonam and ceftazidime-avibactam, aztreonam and amoxicillin-clavulanate, aminoglycosides including plazomicin, cefiderocol, tigecycline are treatment options for UTIs caused by carbapenem-resistant Enterobacteriales (CRE). Treatment options for UTIs caused by multidrug resistant (MDR)-Pseudomonas spp. include fluoroquinolones, ceftazidime, cefepime, piperacillin-tazobactam, carbapenems including imipenem-cilastatin/relebactam, meropenem, and fosfomycin, ceftolozane-tazobactam, ceftazidime-avibactam, aminoglycosides including plazomicin, aztreonam and ceftazidime-avibactam, cefiderocol, and colistin. It is important to use the new antimicrobials wisely for treatment of UTIs caused by MDR-organisms to avoid resistance development.