BACKGROUND: Bacteroides fragilis is the most frequent cause of anaerobic bacteraemia. Although recent data suggest a rise in antimicrobial resistance (AMR) of this and other anaerobic bacteria, surveillance remains limited due to a lack of both data availability and comparability. However, a newly introduced standardised method for antimicrobial susceptibility testing (AST) of anaerobic bacteria has made larger scale surveillance possible for the first time.
OBJECTIVE: To investigate phenotypic AMR of Bacteroides fragilis isolates from bacteraemia across Europe in 2022.
METHODS: In a multicentre approach, clinical microbiology laboratories in Europe were invited to contribute results of AST for Bacteroides fragilis blood culture isolates (including only the first isolate per patient and year). AST of a selection of four antibiotics was performed locally by participating laboratories in a prospective or retrospective manner, using the new EUCAST disc diffusion method on fastidious anaerobe agar (FAA-HB).
RESULTS: A total of 16 European countries reported antimicrobial susceptibilities in 449 unique isolates of Bacteroides fragilis from blood cultures in 2022. Clindamycin demonstrated the highest resistance rates (20.9%, range 0 - 63.6%), followed by piperacillin-tazobactam (11.1%, 0 - 54.5%), meropenem (13.4%, 0 - 45.5%), and metronidazole (1.8%, 0 - 20.0%), all with wide variation between countries.
CONCLUSIONS: Considering that the mean resistance rates across Europe were higher than expected for three of the four anti-anaerobic antibiotics under surveillance, both local AST of clinically relevant isolates of Bacteroides fragilis and continued surveillance on an international level is warranted.

BACKGROUND: Helicobacter pylori infection and its associated diseases represent a significant global health concern. Patients who cannot use amoxicillin pose a therapeutic challenge and necessitate alternative medications. Preliminary research indicates that cefuroxime demonstrates promising potential for eradicating H. pylori infection, and there is a lack of comprehensive review articles on the use of cefuroxime.
METHODS: This study conducts a thorough systematic literature review and synthesis. A comprehensive systematic search was conducted in PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure, China Biology Medicine disc, and Wanfang Data up to January 13, 2024. The search strategy utilized the following keywords: (Cefuroxime) AND (Helicobacter pylori OR Helicobacter nemestrinae OR Campylobacter pylori OR Campylobacter pylori subsp. pylori OR Campylobacter pyloridis OR H. pylori OR Hp) for both English and Chinese language publications. Sixteen studies from five different countries or regions were included in final literature review.
RESULTS: Analysis results indicate that H. pylori is sensitive to cefuroxime, with resistance rates similar to amoxicillin being relatively low. Regimens containing cefuroxime have shown favorable eradication rates, which were comparable to those of the regimens containing amoxicillin. Regarding safety, the incidence of adverse reactions in cefuroxime-containing eradication regimens was comparable to that of amoxicillin-containing regimens or other bismuth quadruple regimens, with no significant increase in allergic reactions in penicillin-allergic patients. Regarding compliance, studies consistently report high compliance rates for regimens containing cefuroxime.
CONCLUSIONS: Cefuroxime can serve as an alternative to amoxicillin for the patients allergic to penicillin with satisfactory efficacies, safety, and compliance.

Patients with brain injuries are at a heightened susceptibility to bacterial pneumonia, and the timely initiation of empiric antibiotic treatment has been shown to substantially reduce mortality rates. Nevertheless, there is a need for knowledge regarding the resistance and prevalence of pulmonary bacterial infections in this patient population. To address this gap, a retrospective study was conducted at a neurosurgical emergency center, focusing on patients with brain injuries. Among the entire patient population, a total of 739 individuals (18.23%) were identified as having bacterial pneumonia, consisting of 1489 strains of Gram-negative bacteria and 205 strains of Gram-positive bacteria. The resistance of Klebsiella pneumoniae to imipenem exhibited a significant increase, rising from 21.74% in 2009 to 96.67% in 2018, and subsequently reaching 48.47% in 2021. Acinetobacter baumannii displayed resistance rates exceeding 80.0% against multiple antibiotics. The resistance profile of Pseudomonas aeruginosa was relatively low. The proportion of Staphylococcus aureus reached its peak at 18.70% in 2016, but experienced a decline to 7.83% in 2021. The abundance of Gram-negative bacteria exceeded that of Gram-positive bacteria by a factor of 5.96. Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus are prominent pathogens characterized by limited antibiotic choices and scarce treatment alternatives for the isolated strains.

UNASSIGNED: To analyze the detection rate, in vitro susceptibility to antibiotics, and carbapenemase types of carbapenem-resistant Enterobacteriaceae (CRE) strains in the clinical samples of a hospital and to provide support for the prevention, control and treatment of CRE-related infections.
UNASSIGNED: Clinical specimens were examined according to the operating procedures of bacteriological tests. Species identification and in vitro drug susceptibility testing were performed on the isolated strains. Carbapenemase inhibitor enhancement testing, which combined the use of 3-aminobenzeneboronic acid and ethylenediaminetetraacetic acid, was conducted to identify the types of carbapenemase in the CRE strains.
UNASSIGNED: In 2021, 2215 CRE strains were isolated from 157196 clinical samples collected in this hospital, presenting a detection rate of 1.4% (2215/157196). A total of 1134 non-repetitive strains of CRE were isolated from 903 patients. The main sources of samples were respiratory tract (494/1134, 43.6%), secretion (191/1134, 16.8%) and blood (173/1134, 15.3%) samples. The cases with the same CRE strain isolated from the samples of two, three and four sites accounted for 12.5%, 4.9%, and 1.1%, respectively. The most common species was Klebsiella pneumoniae (883/1134, 77.9%), followed by Enterobacter cloacae complex (107/1134, 9.4%) and Escherichia coli (96/1134, 8.5%). The rates of resistance to polymyxin B and tigecycline of different species of CRE strains were not significantly different ( P<0.05). Serine carbapenemase-producing strains, metallo-β-lactamase-producing strains, and those producing both enzymes accounted for 82.6% (809/979), 17.2% (168/979), and 0.2% (2/979), respectively.
UNASSIGNED: CRE strains are frequently isolated from samples collected from the respiratory tract, secretion, and blood. The most common strain is serine carbapenemase-producing K. pneumoniae, which has a high resistance rate to various antimicrobial drugs, and risk factors of its associated infections deserve more attention.

BACKGROUND: In the present study, we aimed to describe the proportion of carbapenem-resistant Klebsiella pneumoniae bloodstream infection (CRKP-BSI) in KP-BSI in one Chinese tertiary hospital over 10 years and determine the risk factors and outcomes of CRKP-BSI.
METHODS: We retrospectively analyzed clinical and microbiological data of patients with KP-BSI from January 2010 to December 2019 to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis. KP-BSI only included monomicrobial BSI and health care-acquired BSI.
RESULTS: Among the total 687 isolates of KP-BSI in this study, the rate of CRKP was 39.0% (268/687); this rate in the intensive care unit (ICU) was 65.6% and that in seven high-risk departments (including four ICUs, respiratory medicine, gastroenterology medicine, and hepatobiliary surgery) was 74.6%. The annual rate of CRKP in KP-BSI ranged from 0.0% in 2010 to 54.5% in 2019. The 28-day mortality was 36.2% in patients with CRKP-BSI and 11.7% in those with carbapenem-susceptible K. pneumoniae (CSKP) BSI. Multivariable logistic regression analysis showed that prior ICU stay (odds ratio [OR] 2.485, P < 0.001), hospital stay ≥ 30 days prior to BSI (OR 1.815, P = 0.007), prior mechanical ventilation (OR 2.020, P = 0.014), prior urinary catheter (OR 1.999, P = 0.003), prior carbapenem use (OR 3.840, P < 0.001), hepatobiliary disease (OR 2.943, P < 0.001), pancreatitis (OR 2.700, P = 0.026), and respiratory disease (OR 2.493, P = 0.009) were risk factors of CRKP-BSI. Patients with a first admission (OR 0.662, P = 0.046) had a lower percentage of CRKP-BSI.
CONCLUSIONS: The rapidly rising rate of CRKP-BSI in KP with high mortality requires increased attention. Exposure to carbapenems, ICU stay, invasive mechanical ventilation or urinary catheter, prolonged hospital stay, hepatobiliary disease, pancreatitis, and respiratory disease were found to be risk factors for CRKP-BSI. Strict control measures should be implemented to prevent the emergence and spread of CRKP, especially in high-risk departments.

Purpose: By analyzing the clinical characteristics, etiological characteristics and commonly used antibiotics of patients with ventilator-associated pneumonia (VAP) in intensive care units (ICUs) in the intensive care database. This study aims to provide guidance information for the clinical rational use of drugs for patients with VAP. Method: Patients with VAP information were collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, including their sociodemographic characteristics, vital signs, laboratory measurements, complications, microbiology, and antibiotic use. After data processing, the characteristics of the medications used by patients with VAP in ICUs were described using statistical graphs and tables, and experiences were summarized and the reasons were analyzed. Results: This study included 2,068 patients with VAP. Forty-eight patient characteristics, including demographic indicators, vital signs, biochemical indicators, scores, and comorbidities, were compared between the survival and death groups of VAP patients. Cephalosporins and vancomycin were the most commonly used. Among them, fourth-generation cephalosporin (ForGC) combined with vancomycin was used the most, by 540 patients. First-generati49n cephalosporin (FirGC) combined with vancomycin was associated with the highest survival rate (86.7%). More than 55% of patients were infected with Gram-negative bacteria. However, patients with VAP had fewer resistant strains (<25%). FirGC or ForGC combined with vancomycin had many inflammation-related features that differed significantly from those in patients who did not receive medication. Conclusion: Understanding antibiotic use, pathogenic bacteria compositions, and the drug resistance rates of patients with VAP can help prevent the occurrence of diseases, contain infections as soon as possible, and promote the recovery of patients.

The abuse of antibiotics in aquaculture has led to the increasing rate of antibiotic resistance of aquatic bacteria including Aeromonas, which is an increasing threat to environmental and human health. To date, no epidemiological cut-off values (COWT) for Aeromonas spp. have been established by the Clinical and Laboratory Standards Institute nor the European Commission on Antimicrobial Susceptibility Testing. In this study, commercially prepared minimum inhibitory concentration (MIC) test 96-well plates (dry-form plates) were used to determine the MIC of eight antimicrobial agents against 556 Aeromonas strains. The obtained MIC distributions were simulated and analyzed by NRI and ECOFFinder to obtain tentative COWT values for Aeromonas spp. The COWT values of eight kinds of representative antimicrobial agents including trimethoprim-sulfamethoxazole, erythromycin, doxycycline, neomycin, colistin, florfenicol, enrofloxacin, and ceftazidime for Aeromonas spp. were established and were 0.25, 64/32, 4/2, 8, 4, 1, 0.062/0.125, and 0.5 μg/mL, respectively. Results showed that Aeromonas spp. had a very high proportion of non-wild-type strains to enrofloxacin, florfenicol, and doxycycline, which are the most widely used antimicrobials in aquaculture. The COWT values for Aeromonas spp. obtained in this study can contribute to the final establishment of COWT for Aeromonas spp. internationally.

In the last years, there has been an increase of antimicrobial resistance rates around the world with the misuse and overuse of antimicrobials as one of the main leading drivers. In response to this threat, a variety of initiatives have arisen to promote the efficient use of antimicrobials. These initiatives rely on antimicrobial surveillance systems to promote appropriate prescription practices and are provided by national or global health care institutions with limited consideration of the variations within hospitals. As a consequence, physicians\' adherence to these generic guidelines is still limited. To fill this gap, this work presents an automated approach to performing local antimicrobial surveillance from microbiology data. Moreover, in addition to the commonly reported resistance rates, this work estimates secular resistance trends through regression analysis to provide a single value that effectively communicates the resistance trend to a wider audience. The methods considered for trend estimation were ordinary least squares regression, weighted least squares regression with weights inversely proportional to the number of microbiology records available and autoregressive integrated moving average. Among these, weighted least squares regression was found to be the most robust against changes in the granularity of the time series and presented the best performance. To validate the results, three case studies have been thoroughly compared with the existing literature: (i) Escherichia coli in urine cultures; (ii) Escherichia coli in blood cultures; and (iii) Staphylococcus aureus in wound cultures. The benefits of providing local rather than general antimicrobial surveillance data of a higher quality is two fold. Firstly, it has the potential to stimulate engagement among physicians to strengthen their knowledge and awareness on antimicrobial resistance which might encourage prescribers to change their prescription habits more willingly. Moreover, it provides fundamental knowledge to the wide range of stakeholders to revise and potentially tailor existing guidelines to the specific needs of each hospital.

OBJECTIVE: The aim was to identify the clinical characteristics, outcome, and antimicrobial susceptibility of healthcare-associated bloodstream infections (BSIs) in hematological patients.
METHODS: This retrospectively collected laboratory-based surveillance data include 3404 healthcare-associated BSIs in 2296 patients with a hematological malignancy in hospitals participating in the Finnish Hospital Infection Program from January 1, 2006, to December 31, 2016.
RESULTS: The most common underlying diseases were acute myelogenous leukemia (35%) and non-Hodgkin lymphoma (22%). Gram-positive organisms accounted for 60%-46% and gram-negative organisms for 24%-36% of BSIs in 2006-2016. The most common causative organism was coagulase-negative staphylococci (CoNS) (n = 731). The 7- and 28-day case fatality rates were 5.2% and 11.4%, respectively, and was highest in BSIs caused by Candida species (10.8% and 30.8%). The median age of patients increased from 59 years in 2006-2008 to 62 years in 2015-2016 (P < .01). Five percent of S aureus isolates were resistant to methicillin and five percent of Pseudomonas aeruginosa isolates were multidrug-resistant. Four percent of Klebsiella and seven percent of E coli isolates were resistant to ceftazidime.
CONCLUSIONS: The proportion of gram-positive bacteria decreased and gram-negative bacteria increased over time. The case fatality rate was low and the median age of patients increased during the study.

This study investigated the antimicrobial resistance of isolates from patients with refractory Helicobacter pylori. The resistance rate was 34.1% for amoxicillin, 92.7% for clarithromycin, 65.9% for metronidazole, 85.4% for levofloxacin, and 29.3% for rifabutin. Dual resistance to both clarithromycin and levofloxacin was found in 73.2%. The antimicrobial resistance rate of refractory H. pylori was extremely high, which had become a major consideration in therapeutic challenge.