Prevalence of ESBL non-CRE Escherichia coli and Klebsiella pneumoniae among clinical isolates collected by the SMART global surveillance program from 2015 to 2019

Evolving resistance landscape in gram-negative pathogens: An update on β-lactam and β-lactam-inhibitor treatment combinations for carbapenem-resistant organisms

Antibiotic resistance has become a global threat as it is continuously growing due to the evolution of β-lactamases diminishing the activity of classic β-lactam (BL) antibiotics. Recent antibiotic discovery and development efforts have led to the availability of β-lactamase inhibitors (BLIs) with activity against extended-spectrum β-lactamases as well as Klebsiella pneumoniae carbapenemase (KPC)-producing carbapenem-resistant organisms (CRO). Nevertheless, there is still a lack of drugs that target metallo-β-lactamases (MBL), which hydrolyze carbapenems efficiently, and oxacillinases (OXA) often present in carbapenem-resistant Acinetobacter baumannii. This review aims to provide a snapshot of microbiology, pharmacology, and clinical data for currently available BL/BLI treatment options as well as agents in late stage development for CRO harboring various β-lactamases including MBL and OXA-enzymes.

Epidemiology of bloodstream infections caused by extended-spectrum cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae in Switzerland, 2015-2022: secular trends and association with the COVID-19 pandemic

BACKGROUND

The association between the COVID-19 pandemic and the incidence of invasive infections caused by multidrug-resistant organisms remains a topic of debate.

AIM

To analyse the national incidence rates of bloodstream infections (BSI) caused by Escherichia coli (EC) and Klebsiella pneumoniae (KP) with extended-spectrum cephalosporin-resistance (ESCR) in two distinct regions in Switzerland, each exhibiting varying antimicrobial resistance patterns and that were impacted differently by the pandemic.

METHODS

We analysed data of positive blood cultures prospectively collected by the nationwide surveillance system (ANRESIS) from January 1, 2015, to August 31, 2022. To explore the potential relationship between COVID-19 patient occupancy and ESCR incidence rates, we conducted an in-depth analysis over the two-year pandemic period from April 1, 2020, to March 30, 2022. We employed Quasi-Poisson and logistic regression analyses to investigate these associations.

RESULTS

During the study period, a total of 40997 EC-BSI and 8537 KP-BSI episodes were collected and reported to ANRESIS by the participating hospitals. ESCR was observed in 11% (n=4313) of E. coli and 8% (n=664) of K. pneumoniae, respectively. A significant reduction in ESCR-EC BSI incidence occurred during the pandemic in the region with the highest COVID-19 incidence. Conversely, ESCR-KP BSI incidence initially fell considerably and then increased during the pandemic in both regions, however, this effect was not statistically significant. No association between hospital occupancy from COVID-19 patients and these trends was observed.

CONCLUSION

In the early phase of the COVID-19 pandemic, a decrease in ESCR rates was observed, particularly in ESCR-EC BSI within the most heavily impacted region.

Prevalence, regional distribution, and trends of antimicrobial resistance among female outpatients with urine Klebsiella spp. isolates: a multicenter evaluation in the United States between 2011 and 2019

BACKGROUND

Antimicrobial resistance research in uncomplicated urinary tract infection typically focuses on the main causative pathogen, Escherichia coli; however, little is known about the antimicrobial resistance burden of Klebsiella species, which can also cause uncomplicated urinary tract infections. This retrospective cohort study assessed the prevalence and geographic distribution of antimicrobial resistance among Klebsiella species and antimicrobial resistance trends for K. pneumoniae in the United States (2011-2019).

METHODS

K. pneumoniae and K. oxytoca urine isolates (30-day, non-duplicate) among female outpatients (aged ≥ 12 years) with presumed uUTI at 304 centers in the United States were classified by resistance phenotype(s): not susceptible to nitrofurantoin, trimethoprim/sulfamethoxazole, or fluoroquinolone, extended-spectrum β-lactamase-positive/not susceptible; and multidrug-resistant based on ≥ 2 and ≥ 3 resistance phenotypes. Antimicrobial resistance prevalence by census division and age, as well as antimicrobial resistance trends over time for Klebsiella species, were assessed using generalized estimating equations.

RESULTS

270,552 Klebsiella species isolates were evaluated (250,719 K. pneumoniae; 19,833 K. oxytoca). The most frequent resistance phenotypes in 2019 were nitrofurantoin not susceptible (Klebsiella species: 54.0%; K. pneumoniae: 57.3%; K. oxytoca: 15.1%) and trimethoprim/sulfamethoxazole not susceptible (Klebsiella species: 10.4%; K. pneumoniae: 10.6%; K. oxytoca: 8.6%). Extended-spectrum β-lactamase-positive/not susceptible prevalence was 5.4%, 5.3%, and 6.8%, respectively. K. pneumoniae resistance phenotype prevalence varied (p < 0.0001) geographically and by age, and increased over time (except for the nitrofurantoin not susceptible phenotype, which was stable and > 50% throughout).

CONCLUSIONS

There is a high antimicrobial resistance prevalence and increasing antimicrobial resistance trends among K. pneumoniae isolates from female outpatients in the United States with presumed uncomplicated urinary tract infection. Awareness of K. pneumoniae antimicrobial resistance helps to optimize empiric uncomplicated urinary tract infection treatment.

Epidemiology, clinical outcomes and risk factors of third-generation cephalosporin-resistant Escherichia coli hospitalized infections in remote Australia-a case-control study

Background

Incidence of third-generation cephalosporin-resistant (3GCR) Escherichia coli infections has increased in remote Australia from 2012 to 2018.

Objectives

To describe the epidemiology of 3GCR E. coli in Central Australia.

Methods

A case-control study was conducted in the primary Central Australian hospital. Patient characteristics, antibiotic usage and clinical outcomes were compared between adult hospitalizations with 3GCR and susceptible E. coli isolates in 2018-19. Poisson regression was used to compare the incidence of 3GCR hospitalizations between Indigenous and non-Indigenous individuals. Patient characteristics and antibiotic usage were tested for associations with 3GCR isolates using univariate analysis.

Results

A total of 889 E. coli isolates were identified, of which 187 (21%) were 3GCR. The incidence of 3GCR E. coli infection was 2.15 per 1000 person-years, with an incidence rate ratio of 6.8 (95% CI 4.6-10.1) between Indigenous and non-Indigenous individuals. When compared with the control group, 3GCR E. coli infections were associated with a higher Charlson comorbidity index (CCI ≥3 in 30.7% versus 15.0%, P < 0.001) and were more commonly healthcare associated (52.4% versus 26.7%, P < 0.001). A higher 1 year mortality was observed in the 3GCR group after adjustment for comorbidity (OR = 4.43, P = 0.002), but not at 30 days (2.4% versus 0.0%, P = 0.2). The 3GCR group used more antibiotics in the past 3 months (OR = 5.75, P < 0.001) and 12 months (OR = 3.65, P < 0.001).

Conclusions

3GCR E. coli infections in remote Australia disproportionally affect Indigenous peoples and are associated with a high burden of comorbidities and antibiotic use. Strategies to enhance antimicrobial stewardship should be considered in this remote setting.

Antimicrobial surveillance: A 20-year history of the SMART approach to addressing global antimicrobial resistance into the future

Antimicrobial resistance (AMR) is a major global public health threat, particularly affecting patients in resource-poor settings. Comprehensive surveillance programmes are essential to reducing the high mortality and morbidity associated with AMR and are integral to informing treatment decisions and guidelines, appraising the effectiveness of intervention strategies, and directing development of new antibacterial agents. Various surveillance programmes exist worldwide, including those administered by government bodies or funded by the pharmaceutical industry. One of the largest and longest running industry-sponsored AMR surveillance programme is the Study for Monitoring Antimicrobial Resistance Trends (SMART), which recently completed its 20th year. The SMART database has grown to almost 500 000 isolates from over 200 sites in more than 60 countries, encompassing all major geographic regions and including many sites in low- and middle-income countries. The SMART surveillance programme has evolved in scope over time, including additional antibacterial agents, pathogens and infection sites, in line with changing epidemiology and medical need. Surveillance data from SMART and similar programmes have been used successfully to detect emerging resistance threats and AMR patterns in specific countries and regions, thus informing national and local clinical treatment guidelines. The SMART database can be accessed readily by physicians and researchers globally, which may be especially valuable to those from countries with limited healthcare resources, where surveillance and resistance data are rarely collected. Continued participation from as many sites as possible worldwide and maintenance of adequate funding are critical factors to fully realising the potential of large-scale AMR surveillance programmes into the future.

Antibiotic point prevalence survey and antimicrobial resistance in hospitalized patients across Peruvian reference hospitals

BACKGROUND

Peru reports higher levels than other countries in Latin America of resistance to antimicrobials among Gram-positive and Gram-negative bacteria, however data on antibiotic use in Peru are scarce. This study aims to estimate the prevalence and quality of antibiotic prescription in hospitalized patients and to determine the antibiotic susceptibility rates of bacteria causing key bacterial infections.

METHODS

We carried out a point prevalence survey of antibiotic prescription at ten public hospitals in nine regions of Peru. Data was collected from patients hospitalized during a 3-week period, with details about antibiotic use, patient information, and antimicrobial susceptibility.

RESULTS

1620 patient charts were reviewed; in 924 cases antibiotics were prescribed (57.0 %, range 45.9-78.9 %). Most of the antibiotics (74.2 %) were prescribed as empirical treatment, only 4.4 % as targeted treatment. For 9.5 % of cases the reason for antibiotic use was unknown. Cephalosporins were the most prescribed (30.0 %), followed by carbapenems (11.3 %). Ninety-four blood cultures were positive for bacterial growth, 48.8 % of the Staphylococcus aureus were methicillin-resistant, among Escherichia coli and Klebsiella pneumoniae, 51.7 % and 72.7 % were resistant to third-generation cephalosporins (3GC), 3.4 % and 18.2 % were resistant to carbapenems, respectively. Among bacteria isolated from urine cultures (n = 639), 43.9 % of E. coli and 49.2 % of K. pneumoniae were resistant to 3GC, and 0.9 % of E. coli and 3.2 % of K. pneumoniae were resistant to meropenem.

CONCLUSIONS

The overall proportion of hospitalized patients receiving antibiotics in hospitals from different regions in Peru was high, with only a small proportion receiving targeted treatment. Cephalosporins and carbapenems were the most frequently prescribed antibiotics, reflecting high resistance rates against 3GC and carbapenems in Enterobacterales isolated from blood and urine.

The burden of antimicrobial resistance in the Americas in 2019: a cross-country systematic analysis

Background

Antimicrobial resistance (AMR) is an urgent global health challenge and a critical threat to modern health care. Quantifying its burden in the WHO Region of the Americas has been elusive-despite the region's long history of resistance surveillance. This study provides comprehensive estimates of AMR burden in the Americas to assess this growing health threat.

Methods

We estimated deaths and disability-adjusted life-years (DALYs) attributable to and associated with AMR for 23 bacterial pathogens and 88 pathogen-drug combinations for countries in the WHO Region of the Americas in 2019. We obtained data from mortality registries, surveillance systems, hospital systems, systematic literature reviews, and other sources, and applied predictive statistical modelling to produce estimates of AMR burden for all countries in the Americas. Five broad components were the backbone of our approach: the number of deaths where infection had a role, the proportion of infectious deaths attributable to a given infectious syndrome, the proportion of infectious syndrome deaths attributable to a given pathogen, the percentage of pathogens resistant to an antibiotic class, and the excess risk of mortality (or duration of an infection) associated with this resistance. We then used these components to estimate the disease burden by applying two counterfactual scenarios: deaths attributable to AMR (compared to an alternative scenario where resistant infections are replaced with susceptible ones), and deaths associated with AMR (compared to an alternative scenario where resistant infections would not occur at all). We generated 95% uncertainty intervals (UIs) for final estimates as the 25th and 975th ordered values across 1000 posterior draws, and models were cross-validated for out-of-sample predictive validity.

Findings

We estimated 569,000 deaths (95% UI 406,000-771,000) associated with bacterial AMR and 141,000 deaths (99,900-196,000) attributable to bacterial AMR among the 35 countries in the WHO Region of the Americas in 2019. Lower respiratory and thorax infections, as a syndrome, were responsible for the largest fatal burden of AMR in the region, with 189,000 deaths (149,000-241,000) associated with resistance, followed by bloodstream infections (169,000 deaths [94,200-278,000]) and peritoneal/intra-abdominal infections (118,000 deaths [78,600-168,000]). The six leading pathogens (by order of number of deaths associated with resistance) were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Together, these pathogens were responsible for 452,000 deaths (326,000-608,000) associated with AMR. Methicillin-resistant S. aureus predominated as the leading pathogen-drug combination in 34 countries for deaths attributable to AMR, while aminopenicillin-resistant E. coli was the leading pathogen-drug combination in 15 countries for deaths associated with AMR.

Interpretation

Given the burden across different countries, infectious syndromes, and pathogen-drug combinations, AMR represents a substantial health threat in the Americas. Countries with low access to antibiotics and basic health-care services often face the largest age-standardised mortality rates associated with and attributable to AMR in the region, implicating specific policy interventions. Evidence from this study can guide mitigation efforts that are tailored to the needs of each country in the region while informing decisions regarding funding and resource allocation. Multisectoral and joint cooperative efforts among countries will be a key to success in tackling AMR in the Americas.

Funding

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care using UK aid funding managed by the Fleming Fund.

Screening for extended-spectrum beta-lactamase Escherichia coli in recreational beach waters in Singapore

Aims: As part of Singapore's One Health antimicrobial resistance (AMR) management, this work was designed to understand the AMR burden in recreational beach waters using extended-spectrum beta-lactamase Escherichia coli (ESBL-EC) as an indicator. Materials & methods: A total of 90 water samples were collected from six different recreational beaches over three different time periods. Only 28/90 (31.3%) water samples yielded E. coli colonies ranging from 1 to 80 colony-forming units/100 ml. Results & conclusion: Screening of all colonies using CHROMID® ESBL agar and Luria-Bertani broth supplemented with ceftriaxone showed that none was ESBL-EC. Further monitoring is required to understand the prevalence of ESBL-EC spatiotemporally, contributing to the national AMR surveillance program and providing timely risk assessment for exposure to ESBL-EC.

Comparison of Epidemiological Characteristics Between ESBL and Non-ESBL Isolates of Clinically Isolated Escherichia coli from 2014 to 2022: A Single-Center Study

Purpose

This single-center study aims to investigate the epidemiological characteristics of clinically isolated Escherichia coli from 2014 to 2022.

Methods

In vitro drug sensitivity of E. coli to 20 antibiotics was examined using the microbroth dilution method. A total of 7580 clinical E. coli strains were isolated from 2014 to 2022, among which 56.9% were identified as extended spectrum beta-lactamase-producing strains. The data were analyzed using the software WHONET5.6 and the R language platform.

Results

Over the study period, carbapenem resistance rates increased by more than 50% (2022 [1.34%] vs 2014 [0.8%]) and the annual number of isolates showed an upward trend (1264 in 2022 vs 501 in 2014). Drug resistance rates were the highest for penicillin (75-85%) and lowest for imipenem (1%). The resistance rate of strains isolated from male patients and sputum was found to be higher than that of female patients and urine, except for quinolones (p <0.05). The drug resistance rates from high to low were penicillins (75-85%), tetracycline (64%), quinolones (64-67%), sulfamethoxazole (59.3%), cephalosporins (22-72%), aztreonam (34%), chloramphenicol (21%), amikacin (2.8%), colistin (1.4%), meropenem (1.1%), and imipenem (1%). Urine, sputum, and blood accounted for 51%, 16.6%, and 10.6% of the samples, respectively. A greater number of female patients were included more than male patients (4798[63.3%] vs 2782[26.7%]). Patients aged 50-80 accounted for 64.2% of those surveyed.

Conclusion

Carbapenems remain the optimal choice for treating extended spectrum beta-lactamase-producing E. coli infections (sensitivity rate: 98%). Colistin (87.7%) and amikacin (87%) exhibited good antibacterial activities against carbapenem-resistant E. coli. Long-term and continuous epidemiological surveillance of E. coli can facilitate the development of preventive strategies and control policies.

Activity of ceftolozane/tazobactam and imipenem/relebactam against clinical isolates of Enterobacterales and Pseudomonas aeruginosa collected in central and northern Europe (Belgium, Norway, Sweden, Switzerland)-SMART 2017-21

Objectives

To evaluate the in vitro activities of ceftolozane/tazobactam and imipenem/relebactam against clinical isolates of Gram-negative bacilli collected in four central and northern European countries (Belgium, Norway, Sweden, Switzerland) during 2017-21.

Methods

Participating clinical laboratories each collected up to 250 consecutive Gram-negative isolates per year from patients with bloodstream, intraabdominal, lower respiratory tract or urinary tract infections. MICs were determined by CLSI broth microdilution and interpreted using 2022 EUCAST breakpoints. β-Lactamase genes were identified in select β-lactam-non-susceptible isolate subsets.

Results

Ninety-five percent of all Enterobacterales (n = 4158), 95% of ESBL-positive non-carbapenem-resistant Enterobacterales (non-CRE) phenotype Escherichia coli and 85% of ESBL-positive non-CRE phenotype Klebsiella pneumoniae were ceftolozane/tazobactam susceptible. By country, 88% (Belgium), 91% (Sweden, Switzerland) and 96% (Norway) of ESBL-positive non-CRE phenotype Enterobacterales were ceftolozane/tazobactam susceptible. Greater than ninety-nine percent of non-Morganellaceae Enterobacterales and all ESBL-positive non-CRE phenotype Enterobacterales were imipenem/relebactam susceptible. Ceftolozane/tazobactam (96%) and imipenem/relebactam (95%) inhibited most Pseudomonas aeruginosa (n = 823). Both agents retained activity against ≥75% of cefepime-resistant, ceftazidime-resistant and piperacillin/tazobactam-resistant isolates; 56% and 43% of meropenem-resistant isolates were ceftolozane/tazobactam susceptible and imipenem/relebactam susceptible, respectively. By country, 94% (Belgium), 95% (Sweden) and 100% (Norway, Switzerland) of P. aeruginosa were ceftolozane/tazobactam susceptible and 93% (Sweden) to 98% (Norway, Switzerland) were imipenem/relebactam susceptible. Carbapenemase gene carriage among Enterobacterales and P. aeruginosa isolates was generally low (<1%) or completely absent with one exception: an estimated 2.7% of P. aeruginosa isolates from Belgium carried an MBL.

Conclusions

Recent clinical isolates of Enterobacterales and P. aeruginosa collected in four central and northern European countries were highly susceptible (≥95%) to ceftolozane/tazobactam and imipenem/relebactam.

Whole-Genome Sequencing and Comparative Genomics Analysis of a Newly Emerged Multidrug-Resistant Klebsiella pneumoniae Isolate of ST967

Klebsiella pneumoniae is a common cause of hospital- and community-acquired infections globally, yet its population structure remains unknown for many regions, particularly in low- and middle-income countries (LMICs). Here, we report for the first-time whole-genome sequencing (WGS) of a multidrug-resistant K. pneumoniae isolate, ARM01, recovered from a patient in Armenia. Antibiotic susceptibility testing revealed that ARM01 was resistant to ampicillin, amoxicillin-clavulanic acid, ceftazidime, cefepime, norfloxacin, levofloxacin, and chloramphenicol. Genome sequencing analysis revealed that ARM01 belonged to sequence type 967 (ST967), capsule type K18, and antigen type O1. ARM01 carried 13 antimicrobial resistance (AMR) genes, including blaSHV-27, dfrA12, tet(A), sul1, sul2, catII.2, mphA, qnrS1, aadA2, aph3-Ia, strA, and strB and the extended-spectrum β-lactamase (ESBL) gene blaCTX-M-15, but only one known virulence factor gene, yagZ/ecpA, and one plasmid replicon, IncFIB(K)(pCAV1099-114), were detected. The plasmid profile, AMR genes, virulence factors, accessory gene profile, and evolutionary analyses of ARM01 showed high similarity to isolates recovered from Qatar (SRR11267909 and SRR11267906). The date of the most recent common ancestor (MRCA) of ARM01 was estimated to be around 2017 (95% confidence interval [CI], 2017 to 2018). Although in this study, we report the comparative genomics analysis of only one isolate, it emphasizes the importance of genomic surveillance for emerging pathogens, urging the need for implementation of more effective infection prevention and control practices. IMPORTANCE Whole-genome sequencing and population genetics analysis of K. pneumoniae are scarce from LMICs, and none has been reported for Armenia. Multilevel comparative analysis revealed that ARM01 (an isolate belonging to a newly emerged K. pneumoniae ST967 lineage) was genetically similar to two isolates recovered from Qatar. ARM01 was resistant to a wide range of antibiotics, reflecting the unregulated usage of antibiotics (in most LMICs, antibiotic use is typically unregulated.) Understanding the genetic makeup of these newly emerging lineages will aid in optimizing antibiotic use for patient treatment and contribute to the worldwide efforts of pathogen and AMR surveillance and implementation of more effective infection prevention and control strategies.

Isolation and Identification of Multidrug-Resistant Klebsiella pneumoniae Clones from the Hospital Environment

Global dispersion, hospital outbreaks, and lineage relationships between emerging antibiotic-resistant strains such as Klebsiella pneumoniae are of public health interest. This study aimed to isolate and identify K. pneumoniae clones from third-level healthcare hospitals in Mexico to establish their multidrug-resistant phenotype, phylogeny, and prevalence. Biological and abiotic surface samples were used to isolate K. pneumoniae strains and to test their antibiotic susceptibility to classify them. The housekeeping genes: gapA, InfB, mdh, pgi, phoE, ropB, and tonB were used for multilocus sequence typing (MLST). Phylogenetic networks were constructed with 48 strains. Isolated strains (93) were mainly from urine and blood, 96% were resistant to ampicillin as expected, 60% were extended-spectrum β-lactamases (ESBL), 98% were susceptible to ertapenem and meropenem and 99% were susceptible to imipenem, 46% were multi-drug resistant (MDR), 17% were extensively-drug resistant (XDR), 1% were pan-drug resistant (PDR), and 36% were not classified. The tonB, mdh, and phoE genes were the most variable, and the InfB gene showed positive selection. The most prevalent sequence types (STs) were ST551 (six clones), ST405 (six clones), ST1088 (four clones), ST25 (four clones), ST392 (three clones), and ST36 (two clones). ST706 was PDR, and ST1088 clones were MDR; neither of these STs has been reported in Mexico. The strains analyzed were from different hospitals and locations; thus, it is important to maintain antibiotic surveillance and avoid clone dissemination to prevent outbreaks, adaptation to antibiotics, and the transmission of antibiotic resistance.

Comparison of the relative efficacy of β-lactam/β-lactamase inhibitors and carbapenems in the treatment of complicated urinary tract infections caused by ceftriaxone-non-susceptible Enterobacterales: a multicentre retrospective observational cohort study

BACKGROUND

Treating complicated urinary tract infections (cUTIs) caused by ESBL-producing Enterobacterales represents a significant clinical challenge. The present study was thus developed to explore the relative efficacy of β-lactam/β-lactamase inhibitors (BLBLIs) and carbapenems for the treatment of hospitalized patients suffering from cUTIs caused by BLBLI-susceptible ceftriaxone-non-susceptible Enterobacterales.

METHODS

Data from 557 patients from four Chinese teaching hospitals diagnosed with cUTIs caused by ceftriaxone-non-susceptible Enterobacterales from January 2017 to May 2022 were retrospectively assessed.

RESULT

The 30 day rate of treatment failure, defined by unresolved symptoms or mortality, was 10.4% (58/557). Independent predictors of 30 day treatment failure included immunocompromised status, bacteraemia, septic shock, lack of infection source control and appropriate empirical treatment. When data were controlled for potential confounding variables, BLBLI treatment exhibited a comparable risk of 14 day (OR 1.61, 95% CI 0.86-3.00, P = 0.133) and 30 day treatment failure (OR 1.45, 95% CI 0.66-3.15, P = 0.354) relative to carbapenem treatment for the overall cohort of patients. In contrast, BLBLI treatment in immunocompromised patients was associated with an elevated risk of both 14 day (OR 3.18, 95% CI 1.43-7.10, P = 0.005) and 30 day treatment failure (OR 3.06, 95% CI 1.07-8.80, P = 0.038) relative to carbapenem treatment.

CONCLUSIONS

These results suggested that carbapenem treatment may be superior to BLBLI treatment for immunocompromised patients suffering from cUTIs caused by ceftriaxone-non-susceptible Enterobacterales species. However, these results will need to be validated in appropriately constructed randomized controlled trials to ensure appropriate patient treatment.

Antimicrobial resistance prevalence of Escherichia coli and Staphylococcus aureus amongst bacteremic patients in Africa: a systematic review

OBJECTIVES

Antimicrobial resistance (AMR) is a global concern among infectious diseases. Bloodstream infections can potentially become life-threatening if they become untreatable with conventional antimicrobials. This review aims to provide an understanding of the AMR prevalence and trends of common bacteremic pathogens, namely Escherichia coli and Staphylococcus aureus in the World Health Organization (WHO) Africa region.

METHODS

PubMed and Google Scholar were searched using relevant keywords for published human studies (excluding case reports and reviews) reporting bacteremic AMR data on the pathogens of interest between 2008 and 2019. Two reviewers independently screened the articles against a pre-defined eligibility criterion. Data extraction and analysis were achieved with different platforms: Covidence, Excel, R version 3.6.3, and QGIS v3.4.5. The pooled prevalence, 95% confidence intervals, and I² index (a measure of heterogeneity) were calculated for the various pathogen-antibiotic combinations.

RESULTS

Five hundred sixty-two papers were retrieved, with 27 papers included in the final analysis. Only 23.4% (11/47) of member states of the WHO African region had reports on AMR in bacteremia. The Clinical and Laboratory Standards Institute (CLSI) (78.5%) was the most common standard used in the region. For E. coli, the pooled resistance was: cefotaxime (42%), imipenem (4%), meropenem (0%), and colistin (0%). For S. aureus, the calculated pooled resistance was cloxacillin (34%), oxacillin (12%), and vancomycin (0%). There was a high degree of variation across studies (I² > 90%).

CONCLUSION

The pooled resistance rates indicate a concerning degree of methicillin-resistant and Extended Spectrum-ß-lactamase-producing pathogens. The paucity of AMR data also presents challenges for a comprehensive understanding of the situation in the region. Continent-wide and standardized surveillance efforts therefore need strengthening.

Geographic patterns of global isolates of carbapenem-resistant Klebsiella pneumoniae and the activity of ceftazidime/avibactam, meropenem/vaborbactam, and comparators against these isolates: Results from the Antimicrobial Testing Leadership and Surveillance (ATLAS) program, 2020

Carbapenem-resistant Enterobacterales (CRE) are a growing threat to public health. This study was conducted to determine the prevalence of carbapenem-resistant Klebsiella pneumoniae (CR-KP) and the associated carbapenemase genes using data from the Antimicrobial Testing Leadership and Surveillance (ATLAS) program, 2020. Minimum inhibitory concentrations (MICs) were determined using the broth microdilution method, and carbapenemase genes were detected using multiplex polymerase chain reaction (PCR). Clinical and Laboratory Standards Institute breakpoints were used for interpretation of susceptibility. A total of 6753 K. pneumoniae isolates were collected from 57 countries in six regions worldwide. Of these, 1118 (16.6%) were CR-KP isolates. Among 1079 of the tested CR-KP isolates, 1017 (94.3%) had at least one of the class A (41.0%, 417/1017), B (39.3%, 400/1017), and D (38.8%, 395/1017) carbapenemase genes. The resistance patterns and associated genes differed significantly between the participating countries. India, Greece, and Argentina had the highest rates of carbapenem resistance. Susceptibility to the β-lactamase inhibitor combination, ceftazidime/avibactam was greater than that to meropenem/vaborbactam in all K. pneumoniae (93.7% vs. 90.3%, P < 0.05), CR-KP (63.3% vs. 41.5%, P < 0.05), CR-KP with genes for Klebsiella pneumoniae carbapenemase-like carbapenemase (99.5% vs. 96.0%, P < 0.05), oxacillinase-like carbapenemase (98.7% vs. 4.6%, P < 0.05), and CR-KP without carbapenemase genes (93.5% vs. 79.0%, P < 0.05). CR-KP was the only exception with class B carbapenemase, with susceptibility rates of 1.4% and 9.4% to ceftazidime/avibactam and meropenem/vaborbactam, respectively (P < 0.05). Overall, surveillance results are important for guiding empirical antimicrobial therapy in different regions and for monitoring the global transmission of CR-KP with varying resistance mechanisms.

Clinical prediction models for multidrug-resistant organism colonisation or infection in critically ill patients: a systematic review protocol

INTRODUCTION

Multidrug-resistant organisms (MDROs) are pathogenic bacteria that are the leading cause of hospital-acquired infection which is associated with high morbidity and mortality rates in intensive care units, increasing hospitalisation duration and cost. Predicting the risk of MDRO colonisation or infection for critically ill patients supports clinical decision-making. Several models predicting MDRO colonisation or infection have been developed; however, owing to different disease scenarios, bacterial species and few externally validated cohorts in different prediction models; the stability and applicability of these models for MDRO colonisation or infection in critically ill patients are controversial. In addition, there are currently no standardised risk scoring systems to predict MDRO colonisation or infection in critically ill patients. The aim of this systematic review is to summarise and assess models predicting MDRO colonisation or infection in critically ill patients and to compare their predictive performance.

METHODS AND ANALYSIS

We will perform a systematic search of PubMed, Cochrane Library, CINAHL, Embase, Web of science, China National Knowledge Infrastructure and Wanfang databases to identify all studies describing the development and/or external validation of models predicting MDRO colonisation or infection in critically ill patients. Two reviewers will independently extract and review the data using the Data Extraction for Systematic Reviews of Prediction Modelling Studies checklist; they will also assess the risk of bias using the Prediction Model Risk of Bias Assessment Tool. Quantitative data on model predictive performance will be synthesised in meta-analyses, as applicable.

ETHICS AND DISSEMINATION

Ethical permissions will not be required because all data will be extracted from published studies. We intend to publish our results in peer-reviewed scientific journals and to present them at international conferences on critical care.

PROSPERO REGISTRATION NUMBER

CRD42022274175.