Antimicrobial Resistance Rates Research Articles

Isolation and characterisation of Pseudomonas aeruginosa bacteriophage isolated from Batu Pahat, Johor, Malaysia

The World Health Organization has classified Pseudomonas aeruginosa as a 'Priority One and Critical Pathogen' for which research and design of new antibiotics are urgently needed due to its high rate of antimicrobial resistance. Phage therapy, which uses bacteriophages (phages), has been proposed as an antibacterial agent and shows potential for combating this issue. This study aimed to isolate and characterise bacteriophages from different environmental samples that act specifically against P. aeruginosa. The phages were tested to determine their ability to lyse P. aeruginosa using a spot test. Transmission electron microscopy (TEM) was employed to determine the structure, size and phage family, while specificity and sensitivity tests were conducted using six different bacterial species and 20 clinical multi-drug resistant P. aeruginosa isolates, respectively. Phage PA1 was isolated from Batu Pahat, Johor and using a spot test, PA1 could form clear plaques against P. aeruginosa. PA1 was present in a high titer of 1.06 (± 32.2) x 1010 PFUs/ml. Based on TEM analysis, PA1 was classified as a member of the Myoviridae family. Host-range analysis displayed that PA1 had 100% specificity towards P. aeruginosa and only 45% sensitivity towards different P. aeruginosa clinical isolates. Phage PA1 demonstrated lysis of P. aeruginosa but exhibited a narrow host range, presenting a challenge for phage therapy. A promising approach to overcome this limitation involves using phage cocktails containing multiple strains of phages to broaden the host range and enhance the overall efficacy of phage therapy.

Chemical-mediated virulence: the effects of host chemicals on microbial virulence and potential new antivirulence strategies.

The rising antimicrobial resistance rates and declining antimicrobial discovery necessitate alternative strategies to combat multidrug-resistant pathogens. Targeting microbial virulence is an emerging area of interest. Traditionally, virulence factors were largely restricted to bacteria-derived toxins, adhesins, capsules, quorum sensing systems, secretion systems, factors required to sense, respond to, acquire, or synthesize, and utilize trace elements (such as iron and other metals) and micronutrients (such as vitamins), and other factors bacteria use to establish infection, form biofilms, or damage the host tissues and regulatory elements thereof. However, this traditional definition overlooks bacterial virulence that may be induced or influenced by host-produced metabolites or other chemicals that bacteria may encounter at the infection site. This review will discuss virulence from a non-traditional perspective, shedding light on chemical-mediated host-pathogen interactions and outlining currently available mechanistic insight into increased bacterial virulence in response to host factors. This review aims to define a possibly underestimated theme of chemically mediated host-pathogen interactions and encourage future validation and characterization of the contribution of host chemicals to microbial virulence in vivo. From this perspective, we discuss proposed antivirulence compounds and suggest new potential targets for antimicrobials that prevent chemical-mediated virulence. We also explore proposed host-targeting therapeutics reducing the level of host chemicals that induce microbial virulence, serving as virulence attenuators. Understanding the host chemical-mediated virulence may enable new antimicrobial solutions to fight multidrug-resistant pathogens.

Culture-based susceptibility-guided tailored versus empirical concomitant therapy as first-line Helicobacter pylori treatment: A randomized clinical trial.

With the increasing resistance to antimicrobial agents, susceptibility-guided tailored therapy has been emerging as an ideal strategy for Helicobacter pylori treatment. However, susceptibility-guided tailored therapy requires additional cost, time consumption, and invasive procedure (endoscopy) and its superiority over empirical quadruple therapy as the first-line H. pylori treatment remains unclear. To compare the efficacy of culture-based susceptibility-guided tailored versus empirical concomitant therapy as the first-line Helicobacter pylori treatment. This open-label, randomized trial was performed in four Korean institutions. A total of 312 Patients with H. pylori-positive culture test and naïve to treatment were randomly assigned in a 3:1 ratio to either culture-based susceptibility-guided tailored therapy (clarithromycin-based or metronidazole-based triple therapy for susceptible strains or bismuth quadruple therapy for dual-resistant strains, n=234) or empirical concomitant therapy (n=78) for 10 days. Eradication success was evaluated by 13C-urea breath test at least 4weeks after treatment. Prevalence of dual resistance to both clarithromycin and metronidazole was 8%. H. pylori eradication rates for tailored and concomitant groups were 84.2% and 83.3% by intention-to-treat analysis (p=0.859), respectively, and 92.9% and 91.5% by per-protocol analysis, respectively (p=0.702), which were comparable between the two groups. However, eradication rates for dual-resistant strains were significantly higher in the tailored group than in the concomitant group. All adverse events were grade 1 or 2 based on the Common Terminology Criteria for Adverse Events and the incidence was significantly lower in the tailored group. The proportion of patients discontinuing treatment for adverse events was comparable between the two groups (2.1% vs. 2.6%). The culture-based susceptibility-guided tailored therapy failed to show superiority over the empirical concomitant therapy in terms of eradication rate. Based on these findings, the treatment choice in clinical practice would depend on the background rate of antimicrobial resistance, availability of resources and costs associated with culture and susceptibility testing.

The Etiologic Organisms, Risk Factors, and Outcomes of Nosocomial Bloodstream Infections in Pediatric Patients

Background Much of the knowledge regarding pediatric healthcare-associated infections is based on studies conducted in adults. Here, we investigated clinical risk factors and etiologic organisms, focusing on antibiotic and antifungal resistance in pediatric patients with nosocomial bloodstream infections (nBSIs) in pediatric intensive care units (PICUs). Methods A retrospective evaluation was conducted on pediatric patients with nBSI in the PICUs of a tertiary referral hospital. Results A total of 69 nBSI episodes in 65 patients were observed during the study period. Of these, a total of 40 (57.97%) were caused by Gram-negative bacteria, 6 (8.7%) by Gram-positive bacteria, and 23 (33.33%) by Candida species. The rankings of Gram-negative bacteria were Klebsiella pneumoniae (37.5%), Acinetobacter baumannii (22.5%), and Serratia marcescens (12.5%). Carbapenem resistance was found to be common among K. pneumoniae (40%) and all Acinetobacter species. Most children (54.41%) had spent >28 days in the PICU at the time of diagnosis of nBSI. The presence of central venous catheters was significantly associated with fungal nBSI (P = 0.047). Conclusions A high rate of antimicrobial resistance was observed among pathogens. A central venous catheter was associated with fungemia in children hospitalized in PICUs. Prolonged hospital stay before the diagnosis of BSI and the use of medical devices were found to be common in fungal infections.

Current trends in antimicrobial resistance of ESKAPEEc pathogens from bloodstream infections – Experience of a tertiary care centre in North India

IntroductionBloodstream infections (BSI) due to ESKAPEEc pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanni, Pseudomonas aeruginosa, Enterobacter spp. and Escherichia coli), cause significant mobility and mortality worldwide and are among the most common healthcare associated infections. Rising rates of antimicrobial resistance (AMR) in India are alarming, because of the high infection rates and poor control of antibiotic use. This single-centre, retrospective study was undertaken to identify the patterns of distribution and antimicrobial resistance of ESKAPEEc pathogens in bloodstream infections. MethodologyBlood samples from patients with suspected BSI were cultured and antimicrobial susceptibility testing was performed on automated systems (BD Bactec Fx/BactAlert 3D and Vitek2). The microbiological data on bacterial BSI was retrieved from the laboratory records and antimicrobial resistance profiles were analysed. Results10.7% of the blood culture samples showed bacterial growth during the study period (adult > paediatric and intensive care unit (ICU) > ward > outpatient department (OPD)). E. coli (24%) and K. pneumoniae (20.5%) were the predominant species isolated, followed by S. aureus (9.5%) and A. baumanni (9%). High rates of resistance to third generation cephalosporins, β-lactam-β-lactamase inhibitor combinations (BL-BLI) and carbapenems was observed, in Gram-negative isolates, especially from ICU patients. Methicillin-resistant S. aureus (MRSA) isolates increased from 67% to 88% over the five-year period. Vancomycin-resistance among Enterococcus isolates also escalated to 40% in 2022 with 11% linezolid resistance. ConclusionThe study revealed that more than 77% of bloodstream infections were caused by ESKAPEEc pathogens, with high rates of resistance to most antimicrobials. This reinforces the importance of monitoring the frequency of bacteria and antibiograms in individual treatment and hospital infection control programs.

Current and Future Perspectives on the Management of Helicobacter pylori: A Narrative Review.

The prevalence of Helicobacter pylori (H. pylori), a pathogen, has decreased globally in the last decade. To date, the management of H. pylori has focused on a reactive approach, whereby those diagnosed are treated with antimicrobials and acid suppression in combination. This review article provides an overview of the shift in the management of H. pylori from a reactive approach towards a proactive 'screen and treat' approach; the article reflects the current pharmacological landscape for H. pylori treatment by exploring similarities such as the first-line prescription of quadruple therapy in most countries and provides a summary table of the best practice guidance from Europe, Asia, and North America. It explores significant ongoing challenges in management, such as rising antimicrobial resistance rates, and explores a potential 'work smart' approach to antimicrobial susceptibility testing. We explore the role of registry databases in providing data on treatment efficacy and safety and how they can support a strategic approach to H. pylori treatment. We question if such a database's availability, update, and regular audit should serve as a key quality indicator in a population screening programme. Despite a call for vaccination against H. pylori and decades of research, not many have made it to a phase-three clinical trial. We explore the challenges that have complicated the development of such a vaccine, such as the genetic diversity of H. pylori, immunotolerance, and limitations of mouse models in research; we reflect on how these challenges are contributing to a low likelihood of having a vaccine in the short-medium term. Lastly, it explores the heterogeneity in research on probiotics and their role as an adjunct in the management of H. pylori.

Aligning antimicrobial resistance surveillance with schistosomiasis research: an interlinked One Health approach.

One Health surveillance involves the analysis of human, animal and environmental samples, recognising their interconnectedness in health systems. Such considerations are crucial to investigate the transmission of many pathogens, including drug-resistant bacteria and parasites. The highest rates of antimicrobial resistance (AMR)-associated deaths are observed in sub-Saharan Africa, where concurrently the waterborne parasitic disease schistosomiasis can be highly endemic in both humans and animals. Although there is growing acknowledgment of significant interactions between bacteria and parasites, knowledge of relationships between schistosomes, microbes and AMR remains inadequate. In addition, newly emergent research has revealed the previously underappreciated roles of animals and the environment in both AMR and schistosomiasis transmission. We consider shared environmental drivers and colonisation linkage in this narrative review, with a focus on extended-spectrum beta-lactamase-mediated resistance among bacteria from the Enterobacteriaceae family, which is exceedingly prevalent and responsible for a high burden of AMR-associated deaths. Then we examine novel findings from Malawi, where the landscapes of AMR and schistosomiasis are rapidly evolving, and make comparisons to other geographic areas with similar co-infection epidemiology. We identify several knowledge gaps that could be addressed in future research, including the need to characterise the impact of intestinal schistosomiasis and freshwater contact on intestinal AMR colonisation, before proposing a rationale for connecting AMR surveillance and schistosomiasis research within a One Health framework.

Opportunities to Enhance Diagnostic Testing and Antimicrobial Stewardship: A Qualitative Multinational Survey of Healthcare Professionals.

Antimicrobial resistance (AMR) is a global public health challenge. Global efforts to decrease AMR through antimicrobial stewardship (AMS) initiatives include education and optimising the use of diagnostic technologies and antibiotics. Despite this, economic and societal challenges hinder AMS efforts. The objective of this study was to obtain insights from healthcare professionals (HCPs) on current challenges and identify opportunities for optimising diagnostic test utilisation and AMS efforts. Three hundred HCPs from six countries (representing varied gross national incomes per capita, healthcare system structure, and AMR rates) were surveyed between November 2022 through January 2023. A targeted literature review and expert interviews were conducted to inform survey development. Descriptive statistics were used to summarise survey responses. These findings suggest that the greatest challenges to diagnostic test utilisation were economic in nature; many HCPs reported that AMS initiatives were lacking investment (32.3%) and resourcing (40.3%). High resistance rates were considered the greatest barriers to appropriate antimicrobial use (52.0%). Most HCPs found local and national guidelines to be very useful (≥ 51.0%), but areas for improvement were noted. The importance of AMS initiatives was confirmed; diagnostic practices were acknowledged to have a positive impact on decreasing AMR (70.3%) and improving patient outcomes (81.0%). AMS initiatives, including diagnostic technology utilisation, are pivotal to decreasing AMR rates. Interpretation of these survey results suggests that while HCPs consider diagnostic practices to be important in AMS efforts, several barriers to successful implementation still exist including patient/institutional costs, turnaround time of test results, resourcing, AMR burden, and education. While some barriers differ by country, these survey results highlight areas of opportunities in all countries for improved use of diagnostic technologies and broader AMS efforts, as perceived by HCPs. Greater investment, resourcing, education, and updated guidelines offer opportunities to further strengthen global AMS efforts.

Prevalence and antimicrobial resistance patterns of diarrheagenic and uropathogenic Escherichia coli in Odisha, India

Objective: The aim of this study was to determine the prevalence and antibiotic susceptibility patterns of pathogenic Escherichia (E.) coli causing diarrhea and urinary tract infection (UTI) in patients admitted for treatment in selected health care facilities in Odisha, an eastern Indian State. Methods: A total of 189 rectal swabs from patients with diarrhea and 297 urine samples from patients with UTI were collected from selected health care facilities. E. coli isolates were phenotypically confirmed using MacConkey agar, MacConkey sorbitol agar and blood agar along with biochemical tests. These phenotypically confirmed E. coli isolates were investigated genotypically for known pathogenic E. coli via multiplex PCR. Finally, the pathogenic E. coli was subjected to antibiotic sensitivity test. Results: Culture of 189 rectal swabs and 297 urine samples revealed 46 (24.3%) diarrheagenic E. coli (DEC) and 36 (12.1%) uropathogenic E. coli (UPEC). PCR analysis of DEC identified 27 (14.3%) enterotoxigenic E. coli (ETEC), 8 (4.2%) enteropathogenic E. coli, 10 (5.3%) enteroaggregative E. coli and 1 (0.5%) Enterohemorrhagic E. coli (EHEC) in diarrhea patients and 5 (1.7%) ETEC, 7 (2.4%) enteroaggregative E. coli, 11 (3.7%) EHEC O157:H7 and 1 (0.3%) EHEC non-O157:H7 in UTI patients. DEC and UPEC exhibited multidrug resistance with a high rate of resistance to commonly prescribed antibiotics. A high frequency of ETEC causing diarrhea, atypical enteropathogenic E. coli harboring the eae gene was found among children with acute diarrhea, and ETEC (est+ ) and EHEC O157:H7 were detected in UTI patients along with high antibiotic resistance among DEC and UPEC were important findings. Conclusions: To the best of our knowledge, this is the first study to report the prevalence of DEC and UPEC in patients admitted to hospital in Odisha, India, revealing a high rate of antimicrobial resistance.

Distribution of sequence types and antimicrobial resistance of clinical Pseudomonas aeruginosa isolates from dogs and cats visiting a veterinary teaching hospital in Thailand

BackgroundPseudomonas aeruginosa is an important opportunistic pathogen in dogs and cats and is resistant to several antimicrobial drugs; however, data on the clonal distribution of P. aeruginosa in veterinary hospital are limited. This study aimed to investigate the clonal dissemination and antimicrobial resistance of clinical P. aeruginosa in a veterinary teaching hospital in Thailand within a 1-year period. Minimum inhibitory concentration determination and whole genome sequencing were used for antimicrobial susceptibility analysis and genetic determination, respectively.ResultsForty-nine P. aeruginosa were isolated mostly from the skin, urinary tract, and ear canal of 39 dogs and 10 cats. These isolates belonged to 39 sequence types (STs) that included 9 strains of high-risk clones of ST235 (n = 2), ST244 (n = 2), ST274 (n = 2), ST277 (n = 1), ST308 (n = 1), and ST357 (n = 1). Overall antimicrobial resistance rate was low (< 25%), and no colistin-resistant strains were found. Two carbapenem-resistant strains belonging to ST235 and ST3405 were identified.ConclusionsClinical P. aeruginosa in dogs and cats represent STs diversity. High-risk clones and carbapenem-resistant strains are a public health concern. Nevertheless, this study was limited by a small number of isolates. Continuous monitoring is needed, particularly in large-scale settings with high numbers of P. aeruginosa, to restrict bacterial transfer from companion animal to humans in a veterinary hospital.

Invasive group A streptococcal disease surveillance in Canada, 2021-2022.

Invasive group A streptococcal (iGAS, Streptococcus pyogenes) disease has been a nationally notifiable disease in Canada since 2000. This report summarizes the demographics, emm types, and antimicrobial resistance of iGAS isolates collected in Canada in 2021 and 2022. The Public Health Agency of Canada's National Microbiology Laboratory collaborates with provincial and territorial public health laboratories to conduct national surveillance of invasive S. pyogenes. Emm typing was performed using the Centers for Disease Control and Prevention emm sequencing protocol or extracted from whole-genome sequencing data. Antimicrobial susceptibilities were determined using Kirby-Bauer disk diffusion according to Clinical and Laboratory Standards Institute guidelines or predicted from whole-genome sequencing data based on the presence of resistance determinants. Overall, the incidence of iGAS disease in Canada was 5.56 cases per 100,000 population in 2021, decreasing from the peak of 8.6 cases per 100,000 population in 2018. A total of 2,630 iGAS isolates were collected during 2022, representing an increase from 2021 (n=2,179). In particular, there was a large increase in isolates collected from October to December 2022. The most predominant emm type overall in 2021 and 2022 was emm49, at 21.5% (n=468) and 16.9% (n=444), respectively, representing a significant increase in prevalence since 2018 (p<0.0001). The former most prevalent type, emm1, increased from 0.5% (n=10) in 2021 to 4.8% (n=125) in 2022; similarly, emm12 increased from 1.0% (n=22) in 2021 to 5.8% (n=151) in 2022. These two types together accounted for almost 25% of isolates collected in late 2022 (October to December). Antimicrobial resistance rates in 2021 and 2022 included: 14.9%/14.1% erythromycin resistance, 4.8%/3.0% clindamycin resistance, and <1% chloramphenicol resistance. The increase of iGAS isolates collected in Canada is an important public health concern. Continued surveillance of iGAS is critical to monitor expanding emm types and antimicrobial resistance patterns.

Invasive pneumococcal disease surveillance in Canada, 2021-2022.

Invasive pneumococcal disease (IPD, Streptococcus pneumoniae) has been a nationally notifiable disease in Canada since 2000. The use of conjugate vaccines has caused a shift in the distribution of serotypes over time. This report is a summary of the demographics, serotypes and antimicrobial resistance of IPD isolates collected in Canada in 2021 and 2022. The National Microbiology Laboratory (NML) of the Public Health Agency of Canada in Winnipeg, Manitoba collaborates with provincial and territorial public health laboratories to conduct national surveillance of IPD. There were 1,999 isolates reported in 2021 and 3,775 isolates in 2022. Serotype was determined by the Quellung reaction or whole-genome sequencing (WGS). Antimicrobial susceptibilities were determined by WGS methods, broth microdilution, or data shared by collaborators in the Canadian Antimicrobial Resistance Alliance program at the University of Manitoba. Population-based IPD incidence rates were obtained through the Canadian Notifiable Disease Surveillance System. The incidence of IPD in Canada was 5.62 cases per 100,000 population in 2021, decreasing from the peak of 10.86 cases per 100,000 population in 2018. Serotypes with increasing trends (p<0.05) between 2018 and 2022 included: 4 (6.1%-12.4%), 9V (1.0%-5.1%) and 12F (4.8%-5.4%). The overall prevalence of PCV13 serotypes increased over the same period (31.2%-41.5%, p<0.05) while the prevalence of non-vaccine types decreased significantly (27.3%-21.5%, p<0.0001). The highest rates of antimicrobial resistance in 2021 and 2022 were seen with clarithromycin (21%, 2021; 24%, 2022) and erythromycin (22%, 2021; 24%, 2022). Multidrug-resistant IPD continued to increase from 2018 to 2022 (6.7%-12.6%, p<0.05). The number of cases of IPD continued to decrease in 2021 in comparison to previous years, however, 2022 saw a return to pre-COVID-19 levels. Disease due to PCV13 serotypes 3, 4, 9V and 19F, as well as non-PCV13 serotypes 12F and 20, is increasing in prevalence. Surveillance of IPD to monitor changing serotype distribution and antimicrobial resistance is essential.

Emergence of extensive drug resistance and high prevalence of multidrug resistance among clinical Proteus mirabilis isolates in Egypt

BackgroundProteus mirabilis is an opportunistic pathogen that has been held responsible for numerous nosocomial and community-acquired infections which are difficult to be controlled because of its diverse antimicrobial resistance mechanisms.MethodsAntimicrobial susceptibility patterns of P. mirabilis isolates collected from different clinical sources in Mansoura University Hospitals, Egypt was determined. Moreover, the underlying resistance mechanisms and genetic relatedness between isolates were investigated.ResultsAntimicrobial susceptibility testing indicated elevated levels of resistance to different classes of antimicrobials among the tested P. mirabilis clinical isolates (n = 66). ERIC-PCR showed great diversity among the tested isolates. Six isolates (9.1%) were XDR while all the remaining isolates were MDR. ESBLs and AmpCs were detected in 57.6% and 21.2% of the isolates, respectively, where blaTEM, blaSHV, blaCTX−M, blaCIT−M and blaAmpC were detected. Carbapenemases and MBLs were detected in 10.6 and 9.1% of the isolates, respectively, where blaOXA−48 and blaNDM−1 genes were detected. Quinolone resistant isolates (75.8%) harbored acc(6')-Ib-cr, qnrD, qnrA, and qnrS genes. Resistance to aminoglycosides, trimethoprim-sulfamethoxazole and chloramphenicol exceeded 80%. Fosfomycin was the most active drug against the tested isolates as only 22.7% were resistant. Class I or II integrons were detected in 86.4% of the isolates. Among class I integron positive isolates, four different gene cassette arrays (dfrA17- aadA5, aadB-aadA2, aadA2-lnuF, and dfrA14-arr-3-blaOXA−10-aadA15) and two gene cassettes (dfrA7 and aadA1) were detected. While class II integron positive isolates carried four different gene cassette arrays (dfrA1-sat1-aadA1, estXVr-sat2-aadA1, lnuF- dfrA1-aadA1, and dfrA1-sat2).ConclusionP. Mirabilis ability to acquire resistance determinants via integrons may be held responsible for the elevated rates of antimicrobial resistance and emergence of XDR or even PDR strains limiting the available therapeutic options for management of infections caused by those strains.

The Impact of Urinary Catheterization on the Antibiotic Susceptibility of ESBL-Producing Enterobacterales: A Challenging Duo.

Antimicrobial resistance (AMR) is currently a growing concern among healthcare providers, underscoring the importance of describing the regional susceptibility profile for common microorganisms that are associated with urinary tract infections (UTIs). This knowledge serves as the foundation for proper empirical therapeutic recommendations tailored to local susceptibility patterns. We found a high prevalence of ESBL-producing strains (36.9%), with Escherichia coli and Klebsiella spp. being the most prevalent isolated bacteria. Among the catheterized patients, Klebsiella spp. emerged as the primary etiology, with a significant correlation between catheterization and Proteus spp. (p = 0.02) and Providencia stuartii (p < 0.0001). We observed significant correlations between urinary catheterization and older age (68.9 ± 13.7 years vs. 64.2 ± 18.1 years in non-catheterized patients, p = 0.026) and with the presence of an isolate with extensive drug resistance (p < 0.0001) or even pandrug resistance (p < 0.0001). Susceptibility rates significantly decreased for almost all the tested antibiotics during the study period. Notably, susceptibility was markedly lower among catheterized patients, with the most pronounced differences observed for carbapenems (59.6% versus 83.4%, p < 0.0001) and aminoglycosides (37.1% versus 46.9%, p = 0.0001). We conducted a retrospective study analyzing the susceptibility profiles of 724 extended-spectrum beta-lactamases (ESBL)-producing Enterobacterales isolated from urine cultures. Our focus was on highlighting susceptibility profiles among isolates associated with urinary catheterization and assessing the shifts in the susceptibility rates over time. The constant rise in AMR rates among Enterobacterales presents significant challenges in treating severe infections, particularly among urinary catheterized patients. This trend leaves clinicians with limited or no effective treatment options. Consequently, the development and implementation of personalized treatment protocols are imperative to ensure efficient empirical therapies.

Clinical presentation, antimicrobial resistance, and treatment outcomes of Aeromonas human infections: A 14-year retrospective study and comparative genomics of two isolates from fatal cases.

Aeromonas virulence may not be entirely dependent on the host immune status. Pathophysiologic determinants of disease progression and severity remain unclear. One hundred five patients with Aeromonas infections and 112 isolates were identified, their clinical presentations and outcomes analyzed, and their antimicrobial resistance (AMR) patterns assessed. Two isolates (A and B) from fatal cases of Aeromonas dhakensis bacteremia were characterized using whole genome sequence analysis. Virulence factor- and AMR-encoding genes from these isolates were compared with a well-characterized diarrheal isolate A. dhakensis SSU, and environmental isolate A. hydrophila ATCC_7966T. Skin and soft tissue infections, traumatic wound infections, sepsis, burns, and intraabdominal infections were common. Diabetes, malignancy, and cirrhosis were frequent comorbidities. Male sex, age ≥ 65 years, hospitalization, burns, and intensive care were associated with complicated disease. High rates of AMR to carbapenems and piperacillin-tazobactam were found. Treatment failure was observed in 25.7% of cases. Septic shock and hospital-acquired infections were predictors of treatment failure. All four isolates harbored assorted broad-spectrum AMR genes including blaOXA, ampC, cphA, and efflux pumps. Only clinical isolates possessed both polar and lateral flagellar genes, genes for various surface adhesion proteins, type 3- and -6 secretion systems and their effectors, and toxin genes, including exotoxin A. Both isolates A and B were resistant to colistin and harbored the mobile colistin resistance-3 (mcr-3) gene. Empirical therapy tailored to local Aeromonas antibiograms may facilitate more favorable outcomes, while advanced diagnostic methods may aid in identifying correct Aeromonas spp. of significant clinical importance.

Molecular epidemiology and antimicrobial resistance profiles of Klebsiella pneumoniae isolates from hospitalized patients in different regions of China.

The increasing incidence of Klebsiella pneumoniae and carbapenem-resistant Klebsiella pneumoniae (CRKP) has posed great challenges for the clinical anti-infective treatment. Here, we describe the molecular epidemiology and antimicrobial resistance profiles of K. pneumoniae and CRKP isolates from hospitalized patients in different regions of China. A total of 219 K. pneumoniae isolates from 26 hospitals in 19 provinces of China were collected during 2019-2020. Antimicrobial susceptibility tests, multilocus sequence typing were performed, antimicrobial resistance genes were detected by polymerase chain reaction (PCR). Antimicrobial resistance profiles were compared between different groups. The resistance rates of K. pneumoniae isolates to imipenem, meropenem, and ertapenem were 20.1%, 20.1%, and 22.4%, respectively. A total of 45 CRKP isolates were identified. There was a significant difference in antimicrobial resistance between 45 CRKP and 174 carbapenem-sensitive Klebsiella pneumoniae (CSKP) strains, and the CRKP isolates were characterized by the multiple-drug resistance phenotype.There were regional differences among antimicrobial resistance rates of K. pneumoniae to cefazolin, chloramphenicol, and sulfamethoxazole,which were lower in the northwest than those in north and south of China.The mostcommon sequence type (ST) was ST11 (66.7% of the strains). In addition, we detected 13 other STs. There were differences between ST11 and non-ST11 isolates in the resistance rate to amikacin, gentamicin, latamoxef, ciprofloxacin, levofloxacin, aztreonam, nitrofurantoin, fosfomycin, and ceftazidime/avibactam. In terms of molecular resistance mechanisms, the majority of the CRKP strains (71.1%, 32/45) harbored blaKPC-2, followed by blaNDM (22.2%, 10/45). Strains harboring blaKPC or blaNDM genes showed different sensitivities to some antibiotics. Our analysis emphasizes the importance of surveilling carbapenem-resistant determinants and analyzing their molecular characteristics for better management of antimicrobial agents in clinical use.

Implementation of the EUCAST rapid antimicrobial susceptibility test (RAST) for carbapenemase/ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates, and its effect on mortality.

With the rise in antimicrobial resistance, there is a growing demand for rapid antimicrobial susceptibility testing (RAST). In this study, we applied the EUCAST RAST method to ESBL/carbapenemase-producing Escherichia coli and Klebsiella pneumoniae isolates without using advanced identification systems and analysed the effect of this method on mortality rates Also the clinical impact of this method on patients infected with these bacteria and its effect on mortality rates were investigated. RAST was used for clinical blood cultures containing carbapenemase/ESBL-producing E. coli and K. pneumoniae without advanced identification systems (e.g. MALDI TOF), with preliminary identification by simple diagnostic tests (predicted RAST, or p-RAST), and its categorical agreement was investigated. The impact of the method on mortality was analysed by comparing the clinical data of patients whose blood cultures were subject to p-RAST (p-RAST group, n = 49) and those who were not subject to p-RAST (non-RAST group, n = 145). p-RAST results were analysed based on 539 antibiotic-bacteria combinations. Total error rates at 4, 6 and 8 h of incubation were 2.9%, 3.9% and 3.8%, respectively. In the p-RAST group, patients who did not receive appropriate antibiotics (29/45, 59.1%) were switched to appropriate treatment within 8 h at the latest. In contrast, in the non-RAST group, treatment of patients who received inappropriate antibiotics (79/145, 54.5%) could be changed after at least 24 h. Mortality rates were lower in the p-RAST group than in the non-RAST group (28.6% versus 51.7%, P = 0.005). p-RAST can be used safely in hospital laboratories with high rates of antimicrobial resistance and can reduce mortality rates by shortening the transition time to appropriate treatment.

Evolution of Antimicrobial Resistance in Klebsiella pneumoniae over 3 Years (2019-2021) in a Tertiary Hospital in Bucharest, Romania.

The antimicrobial resistance (AMR) of Klebsiella pneumoniae recorded a steep upward trend over the last two decades, among which carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the most concerning strains considering the development and spread of AMR. The aim of this study was to analyze the evolution of AMR for Klebsiella pneumoniae and to describe the risk factors of AMR for Klebsiella pneumoniae, including the COVID-19 pandemic. We conducted a retrospective study on Klebsiella pneumoniae non-duplicative isolates collected from patients admitted to a tertiary hospital in Bucharest, Romania, from January 2019 to December 2021. We evaluated AMR changes by comparing resistance between 2019 and the mean of 2020-2021. The rates of AMR increased for third-generation cephalosporins, carbapenems, aminoglycosides, fluoroquinolones, and colistin and decreased for trimethoprim/sulfamethoxazole (TMP/SMX), 45.7% in 2019 vs. 28.3% in 2021. A longer length of hospital stay (ꭓ2 = 49.68, p < 0.01); recent antibiotic consumption, RR = 1.38, 95% CI [1.21, 1.57]; and recent contact with hospital settings, RR = 1.54, 95% CI [1.32, 1.8] were risk factors for multidrug-resistant (MDR) Klebsiella pneumoniae. The AMR of Klebsiella pneumoniae increased during 2020-2021 for most of the potential active antibiotics; only TMP/SMX resistance decreased, and it may represent a treatment option for CRKP or MDR Klebsiella pneumoniae infections. Decreasing the excessive use of antibiotics and the implementation of prevention and control measures in healthcare settings are mandatory for avoiding further increases in the AMR rate of Klebsiella pneumoniae.

Characteristics and Evolution of Microbial Drug Resistance in Burned Patients.

Wound infection is a serious complication in burn injury, which is a common form of trauma and an important public health issue. We investigated samples from burn and nonburn wounds for microbial characteristics and temporal trends of antibiotic resistance. Wound samples were collected from 369 burned patients and 927 non-burned individuals admitted from 2007 to 2017. Higher frequency of Acinetobacter baumannii, Klebsiella pneumonia, and Pseudomonas aeruginosa was observed in samples from burned individuals when compared to those from non-burned. The prevalence of different groups of bacteria varied when the samples were stratified according to age and sex. The antimicrobial resistance profiles showed a significant difference between burned and non-burned patients. The different temporal trends of antimicrobial resistance rates were also found, which may be critical for the proper selection of antibiotics in burn treatment. The present study suggested that frequent pathogens and antibacterial resistance evolution could differ between burn wounds and other wounds. Therefore, periodic surveillance of antibiotic resistance patterns in the burn unit might help physicians properly select antibiotics for treatment.

Antimicrobial resistance and ESBL production in uropathogenic Escherichia coli: a systematic review and meta-analysis in Ethiopia.

Antimicrobial resistance (AMR) is a serious threat to global health systems. Escherichia coli is a major cause of urinary tract infections (UTIs). Understanding the AMR patterns of uropathogenic E. coli (UPEC) is crucial for effective public health interventions worldwide. This systematic review and meta-analysis aimed to consolidate existing research and provide a comprehensive information on AMR UPEC in Ethiopia. We systematically searched databases such as PubMed, Web of Science, and Science Direct, along with including articles from Google Scholar. Data were extracted into Microsoft Excel and analysed using STATA 17.0. Cohen's kappa was computed to assess reviewer agreement, while the I2 statistic evaluated heterogeneity. Egger's tests were conducted to detect publication bias, and random-effects models were utilized to estimate the pooled resistance, with AMR rates for each antibiotic pooled separately. UPEC showed resistance rates, ranging from 3.64% (95% CI: -4.38% to 11.67%) for amikacin to 85.32% (95% CI: 78.6%-92.04%) for ampicillin. Highest resistance was to ampicillin (85.32%), followed by amoxicillin at 82.52% (95% CI: 74.3%-90.74%), tetracycline at 60.67% (95% CI: 51.53%-69.81%) and trimethoprim/sulfamethoxazole at 57.17% (95% CI: 49.93%-64.42%). Conversely, resistance rates were lower for amikacin at 3.64% and meropenem at 5.26% (95% CI: 2.64%-7.88%). UPEC demonstrated a pooled MDR rate of 79.17% (95% CI: 70.32%-88.01%) and a pooled ESBL production rate of 29.16% (95% CI: 22.36%-38.55%). High levels of AMR were observed in UPEC strains, highlighting a critical public health issue requiring urgent action through robust antimicrobial stewardship and surveillance to preserve effective UTI treatment options.