Consensus statement on the role of fluoroquinolones in the management of urinary tract infections

Antimicrobial activity of ceftazidime-avibactam and comparators against levofloxacin-resistant Escherichia coli collected from four geographic regions, 2012-2018

BACKGROUND

Increases in resistance to fluoroquinolones have been correlated with the use of levofloxacin in the treatment of infections caused by Escherichia coli. The analysis presents the in vitro activity of ceftazidime-avibactam and comparator agents against 10,840 levofloxacin-resistant E. coli isolates collected from four geographic regions (Africa/Middle East, Europe, Asia/South Pacific, Latin America) between 2012 and 2018.

METHODS

Non-duplicate clinical isolates of E. coli were collected from participating centres and shipped to IHMA, Inc., (Schaumburg, IL, USA). Susceptibility testing was performed with frozen broth microdilution panels manufactured by IHMA, according to CLSI guidelines. Levofloxacin-resistance was defined at a minimum inhibitory concentration of ≥ 2 mg/L. Isolates collected between 2012 and 2015 were tested for extended-spectrum β-lactamase (ESBL) activity by determining susceptibility to cefotaxime, cefotaxime-clavulanate, ceftazidime, and ceftazidime-clavulanate as recommended by CLSI guidelines. Isolates collected between 2016 and 2018 were identified as ESBL-positive by genotype using multiplex polymerase chain reaction assays.

RESULTS

A total of 74.8% of levofloxacin-resistant E. coli isolates in the analysis were from three culture sources: urinary tract infections (N = 3229; 29.8%), skin and skin structure infections (N = 2564; 23.7%) and intra-abdominal infections (N = 2313; 21.3%). Susceptibility rates to ceftazidime-avibactam were consistently high in all regions against both ESBL-positive (97.0% in Asia/South Pacific to 99.7% in Africa/Middle East and Latin America) and ESBL-negative isolates (99.4% in Asia/South Pacific to 100% in Latin America). Susceptibility was also high in each region among ESBL-positive and ESBL-negative isolates to colistin (≥ 98.5%), imipenem (≥ 96.5%), meropenem (≥ 96.5%) and tigecycline (≥ 94.1%).

CONCLUSIONS

Antimicrobial susceptibility to ceftazidime-avibactam among levofloxacin-resistant E. coli isolates, including ESBL-positive isolates, collected from four geographical regions between 2012 and 2018 was consistently high. Susceptibility to the comparator agents colistin, tigecycline, imipenem and meropenem was also high.

Association of Infections and Use of Fluoroquinolones With the Risk of Aortic Aneurysm or Aortic Dissection

IMPORTANCE

Prior observational studies have suggested that fluoroquinolone use may be associated with more than 2-fold increased risk of aortic aneurysm or aortic dissection (AA/AD). These studies, however, did not fully consider the role of coexisting infections and the risk of fluoroquinolones relative to other antibiotics.

OBJECTIVE

To estimate the risk of AA/AD associated with infections and to assess the comparative risk of AA/AD associated with fluoroquinolones vs other antibiotics with similar indication profiles among patients with the same types of infections.

DESIGNS, SETTINGS, AND PARTICIPANTS

This nested case-control study identified 21 651 176 adult patients from a nationwide population-based health insurance claims database from January 1, 2009, to November 30, 2015. Each incident case of AA/AD was matched with 10 control individuals by age, sex, and follow-up duration in the database using risk-set sampling. Analysis of the data was conducted from April 2019 to March 2020.

EXPOSURES

Infections and antibiotic use within a 60-day risk window before the occurrence of AA/AD.

MAIN OUTCOMES AND MEASURES

Conditional logistic regression was used to estimate the odds ratios (ORs) and 95% CIs comparing infections for which fluoroquinolones are commonly used with no infection within a 60-day risk window before outcome occurrence, adjusting for baseline confounders and concomitant antibiotic use. The adjusted ORs comparing fluoroquinolones with antibiotics with similar indication profiles within patients with indicated infections were also estimated.

RESULTS

A total of 28 948 cases and 289 480 matched controls were included (71.37% male; mean [SD] age, 67.41 [15.03] years). Among these, the adjusted OR of AA/AD for any indicated infections was 1.73 (95% CI, 1.66-1.81). Septicemia (OR, 3.16; 95% CI, 2.63-3.78) and intra-abdominal infection (OR, 2.99; 95% CI, 2.45-3.65) had the highest increased risk. Fluoroquinolones were not associated with an increased AA/AD risk when compared with combined amoxicillin-clavulanate or combined ampicillin-sulbactam (OR, 1.01; 95% CI, 0.82-1.24) or with extended-spectrum cephalosporins (OR, 0.88; 95% CI, 0.70-1.11) among patients with indicated infections. The null findings for fluoroquinolone use remained robust in different subgroup and sensitivity analyses.

CONCLUSIONS AND RELEVANCE

These results highlight the importance of accounting for coexisting infections while examining the safety of antibiotics using real-world data; the findings suggest that concerns about AA/AD risk should not deter fluoroquinolone use for patients with indicated infections.

Recommended Initial Antimicrobial Therapy for Emphysematous Pyelonephritis: 51 Cases and 14-Year-Experience of a Tertiary Referral Center

The aim of this study was to investigate the profiles of pathogens and patterns of antibiotic resistance of emphysematous pyelonephritis (EPN), offering recommendations for initial antibiotic treatment.Between January, 2001, and November, 2014, demographic data, presenting clinical features, management strategies, and treatment outcomes of 51 patients with EPN were retrospectively reviewed, analyzing microbiological characteristics of causative pathogens and patterns of antibiotic resistance.Overall survival rate was 90.2% (46/51). Pathogens isolated most frequently were Escherichia coli (49.0%), Klebsiella pneumoniae (19.6%), and Proteus mirabilis (17.7%). Approximately 24% of E coli isolates and 22% K pneumoniae isolates were resistant to fluoroquinolones. Improper empiric antibiotic use (P = 0.02) and third-generation cephalosporin-resistant pathogens (G3CRP) (P = 0.01) were significantly more common in cases of patient fatality. Prior hospitalization and antibiotic use within past year (P = 0.03), need for emergency hemodialysis (P = 0.03), and development of disseminated intravascular coagulation (DIC) (P = 0.03) were factors correlating significantly with microbial resistance to third-generation cephalosporins. The area under the receiver operating characteristic curve was 0.91. The cut-off point determined by the maximum Youden index for 2 of these 3 factors yielded a sensitivity of 0.8 and specificity of 0.93.Third-generation cephalosporins are recommended as initial treatment of EPN. In patients with histories of prior hospitalization and antibiotic use and in those needing emergency hemodialysis or developing DIC, carbapenem is the empiric antibiotic of choice. Patients presenting with 2 or more factors carry the highest risk of G3CRP involvement. Fluoroquinolone and gentamicin should be avoided.

Comparison of community-onset healthcare-associated and hospital-acquired urinary infections caused by extended-spectrum beta-lactamase-producing Escherichia coli and antimicrobial activities

OBJECTIVE

We aimed to compare community-onset healthcare-associated (CO-HCA) and hospital-acquired (HA) urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in terms of epidemiology, clinical outcomes and antimicrobial activities.

METHODS

Patients from both groups with ESBL-producing E. coli detected by urine culture between January 2009 and January 2011 were included in this retrospective study. Relevant demographical, microbiologic and clinical data were obtained from case records.

RESULTS

A total of 173 patients (mean age of 58 years, 74% female) were included, of whom 75 (43.4%) had a CO-HCA UTI and 98 (56.6%) had an HA UTI. Eighty (46.2%) patients had more than one comorbid disease, of whom 57 (32.5%) had urological problems. The most common clinical manifestations were pyelonephritis (43.9%) and urosepsis (16.2%). An age of > 65 years (p = 0.005) in addition to urinary catheterisation (p = 0.001), urosepsis (p = 0.001) and mortality (p = 0.001) were significantly more common in the HA UTI group. Acute cystitis (p = 0.027), complicated cystitis (p = 0.001) and non-urologic neoplasm (p = 0.032) were significantly more common in the CO-HCA UTI group. No isolate was resistant to carbapenems or fosfomycin. Sensitivities to nitrofurantoin, amikacin, trimethoprim sulfamethoxazole-trimoxazole and quinolones were 97.6%, 89%, 29.4% and 17.9% respectively. Both groups showed similar rates of antibiotic resistance.

CONCLUSION

ESBL-producing E. coli should be taken into consideration in patients with a CO HCA UTI, not only in hospital settings but also in outpatient settings. We suggest ertapenem as a first-line empirical treatment for patients with an upper UTI and fosfomycin and nitrofurantoin for those with a lower UTI when ESBL-producing E. coli is suspected.

Emerging resistance problems and future perspectives in pharmacotherapy for complicated urinary tract infections

INTRODUCTION

Urinary tract infections (UTIs) are among the most common infectious diseases and contribute to high financial burden worldwide. Administration of appropriate antibiotic therapy is the key to achieving good therapeutic outcomes. The authors review the current status of global or regional epidemiology, especially on the antimicrobial resistance and several potential agents against complicated UTIs by multidrug-resistant (MDR) pathogens.

AREAS COVERED

The authors summarized the susceptibility status on several major surveillance programs on uropathogens, focusing on Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant enterococci. Besides, the current perspectives of several potential antimicrobials against MDR uropathogens available for UTIs were also reviewed.

EXPERT OPINION

High resistance to broad-spectrum antibiotics, especially to extended-spectrum β-lactams, carbapenems, and fluoroquinolones among uropathogens emerges as a critical problem in many countries. Appropriate antimicrobial stewardship and continuous surveillance are necessary to monitor the trends of susceptibility for main pathogens. For these MDR uropathogens, polymyxin, fosfomycin, tigecycline, nitrofurantoin, linezolid, and daptomycin might be potential treatments for patients with uncomplicated and complicated UTIs in some countries, although they might not be approved by their regulation. However, more clinical evidence and more extensive meta-analyses are needed to evaluate and confirm the effectiveness of their usage in countries with a high prevalence of multidrug resistance.

Risk factors and clinical impact of levofloxacin or cefazolin nonsusceptibility or ESBL production among uropathogens in adults with community-onset urinary tract infections

BACKGROUND

Gram-negative bacilli causing community-onset urinary tract infections (CoUTIs) are getting increasingly resistant to antimicrobial agents. Clinical significance and risk factors of the acquisition of antimicrobial-nonsusceptible pathogens are still under investigation.

METHODS

A prospective study was performed in the medical wards of two hospitals in southern Taiwan between August 2009 and January 2012. Patients were enrolled if they were aged >18, admitted through the emergency department, and had CoUTI due to Enterobacteriaceae isolates.

RESULTS

Overall 136 adults with CoUTI were enrolled. Their mean age was 67 years and females were predominant (68.4%). Comorbidities, such as diabetes mellitus (30.1%) and hypertension (54.4%), were common. Escherichia coli (111, 81.6%) was the predominant species, followed by Klebsiella pneumoniae (11, 8.1%), and Proteus mirabilis (7, 5.1%). Nine (8.0%) of E. coli isolates and 5 (45%) of K. pneumoniae isolates had extended-spectrum β-lactamase (ESBL) production. Out of 122 non-ESBL producing isolates, 35 (28.7%) and 31 (25.4%) were nonsusceptible to levofloxacin and cefazolin, respectively. In the multivariate analysis, several clinical characters were found to be independently associated with CoUTIs due to levofloxacin-nonsusceptible (i.e. males, recent hospitalization, underlying old stroke, diabetes mellitus, and altered consciousness, or absence of chills, pyuria, or tachycardia), cefazolin-nonsusceptible (i.e. males, recent hospitalization, underlying old stroke, absence of fever or chills), or ESBL-producing isolates (i.e. recent hospitalization or antimicrobial therapy). All patients survived and discharged. However, the patients with CoUTIs due to levofloxacin-nonsusceptible (16.1 vs. 7.5 days, p < 0.01), cefazolin-nonsusceptible (15.4 vs. 8.4 days, p < 0.01) or ESBL-producing (16.7 vs. 9.6 days; p < 0.01) pathogens had a longer hospitalization stay than those due to their susceptible comparators.

CONCLUSION

Several host factors were recognized to be independently associated with the acquisition of UTIs due to levofloxacin- or cefazolin- nonsusceptible, or ESBL-producing Gram-negative bacilli. The clinical impact of UTIs due to nonsusceptible uropathogens is that they result in the prolongation of hospital stays.

Correlation between levofloxacin consumption and the incidence of nosocomial infections due to fluoroquinolone-resistant Escherichia coli

BACKGROUND/PURPOSE

The relationship between fluoroquinolone resistance in Escherichia coli isolates causing nosocomial infection and hospital antibiotic consumption were investigated. Restriction of levofloxacin use was implemented to control the incidence of fluoroquinolone-resistant E coli in the hospital.

METHODS

The study was conducted from January 2004 to December 2010. Antimicrobial agent consumption was obtained from the pharmacy computer system and presented as the defined daily doses per 1000 patient-days every 6 months. The incidence of fluoroquinolone-resistant E coli isolates causing nosocomial infections was obtained from the Department of Infection Control every 6 months. An antimicrobial stewardship program, restricting levofloxacain use, was implemented in July 2007.

RESULTS

The incidence of fluoroquinolone-resistant E coli causing nosocomial infections was significantly correlated with fluoroquinolone usage (p = 0.005), but not with the use of third- or fourth-generation cephalosporins, piperacillin-tazobactam, or carbapenems. Parenteral (p = 0.002), oral (p = 0.018), and total levofloxacin (p = 0.001) use were significantly correlated with the extent of fluoroquinolone resistance. With a reduction of levofloxacin use, a decrease of the incidence of fluoroquinolone resistance in E coli isolates was observed.

CONCLUSION

There is a significant correlation between levofloxacin use and the incidence of nosocomial fluoroquinolone-resistant E coli isolates. The incidence of fluoroquinolone-resistant E coli could be reduced by limiting levofloxacin consumption.