Epidemiology of extended-spectrum β-lactamases in Enterobacterales in Taiwan for over two decades

The emergence of antimicrobial resistance among microorganisms is a serious public health concern, and extended-spectrum β-lactamases (ESBL)-producing Enterobacterales is one of the major concerns among antibiotic-resistant bacteria. Although the prevalence of ESBL in Enterobacterales has been increasing with time, the prevalence of ESBL could differ according to the species, hospital allocation, sources of infections, nosocomial or community acquisitions, and geographic regions. Therefore, we conducted a comprehensive review of the epidemiology of ESBL-producing Enterobacterales in Taiwan. Overall, the rates of ESBL producers are higher in northern regions than in other parts of Taiwan. In addition, the genotypes of ESBL vary according to different Enterobacterales. SHV-type ESBLs (SHV-5 and SHV-12) were the major types of Enterobacter cloacae complex, but Serratia marcescens, Proteus mirabilis, Escherichia coli, and Klebsiella pneumoniae were more likely to possess CTX-M-type ESBLs (CTX-M-3 and CTX-M-14). Moreover, a clonal sequence type of O25b-ST131 has been emerging among urinary or bloodstream E. coli isolates in the community in Taiwan, and this clone was potentially associated with virulence, ESBL (CTX-M-15) production, ciprofloxacin resistance, and mortality. Finally, the evolution of the genetic traits of the ESBL-producing Enterobacterales isolates helps us confirm the interhospital and intrahospital clonal dissemination in several regions of Taiwan. In conclusion, continuous surveillance in the investigation of ESBL production among Enterobacterales is needed to establish its long-term epidemiology.

Impact of the beta-lacta test on the management of urinary tract infections at the emergency department

INTRODUCTION

Rapid detection of extended-spectrum β-lactamases is essential. In this study, we evaluated the potential impact of β-lacta test on both the times to appropriate antibiotic therapy and to the implementation of patient isolation measures.

PATIENTS AND METHODS

We included prospectively all the patients admitted to the emergency department for clinical suspicion of urinary tract infection. Compared with physician's decision, we analysed the potential impact of β-lacta test on the initial antibiotic therapy and on the implementation of hygiene measures. This study has been registered under number NCT02897609.

RESULTS

We included 203 patients, 43% with acute pyelonephritis and 21% with acute prostatitis. The β-lacta test had a 95.2% sensitivity and a 99.5% specificity to detect extended-spectrum β-lactamases. Taking the β-lacta test results into account would have decreased significantly both the times to appropriate therapy and to isolation measures from 54 to 2.7 h and from 55.2 to 2.6 h, respectively.

CONCLUSION

The β-lacta test could reduce significantly the times to appropriate therapy and implementation of isolations measures.

Mortality Due to Nosocomial Infection with Klebsiella pneumoniae ESBL<sup/>

Klebsiella pneumoniae is one of the most important hospital pathogens, particularly concerning the multidrug-resistant strain ESBL⁺. The aim of this study was to evaluate nosocomial infections with K. pneumoniae ESBL⁺ in the context of infection location, risk factors, and prognosis. This hospital study was conducted retrospectively and covered a 3 months' period. The infection with K. pneumoniae ESBL⁺ was diagnosed in 36 patients (19 women and 17 men) of the mean age of 74.2 ± 14.8 years. The number of infected patients amounted to 2.2% of all patients admitted to Czerniakowski Hospital in Warsaw, Poland, over the study time. Twenty of these patients died (13 women and 7 men), representing 14% of all hospital deaths at the time. The infection with K. pneumoniae ESBL⁺ occurred most frequently in the department of internal diseases, and rarely in neurology or intensive care wards. Bacteria was most often isolated from the urine, with the most distinct association between the use of urinary catheters and death (p = 0.019). We conclude that infections with K. pneumoniae ESBL⁺ were associated with over 55% mortality and usually occurred in the setting of internal diseases. Deaths due to K. pneumoniae ESBL⁺ infection were significantly related to the use of urinary bladder catheters.

Extended-spectrum β-lactamase-producing Escherichia coli bacteremia: Comparison of pediatric and adult populations

BACKGROUND/PURPOSE

The prevalence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is increasing worldwide. This study investigated the clinical features and bacteriology of pediatric patients with ESBL-producing E. coli bacteremia and compared their characteristics with those of adult patients.

METHODS

Clinical and laboratory data from all of the 41 patients aged ≤18 years diagnosed with E. coli bacteremia were collected over 5 years. Patients aged >18 years diagnosed with E. coli bacteremia, matched 1:1 for calendar time, were enrolled as the adult group. All E. coli isolates were tested for their blaCTX-M group and sequence type 131 (ST131). A novel seven-single nucleotide polymorphism-based clonotyping test was applied to detect the septatypes of each isolate.

RESULTS

In the adult group, patients with ESBL-producing E. coli bacteremia had more previous hospitalizations and antimicrobial agent use than did those with non-ESBL-producing E. coli bacteremia, but these differences were not found in pediatric group. In the pediatric group, the proportion of isolates producing CTX-M group 9 was higher than that in the adult group (85.7% vs. 42.9%; p < 0.05). Among both groups, there were more E. coli ST131 in ESBL isolates in than there were non-ESBL isolates. The distribution of septatypes was more homogenous in ESBL-producing E. coli among the pediatric patients than among the adult patients.

CONCLUSION

ST131 was the major clone causing E. coli bacteremia in both pediatric and adult populations. The pediatric population demonstrated a higher number of isolates producing CTX-M group 9 with more homogenous septatypes compared with the adult population.