Prevalence, genetic diversity, and drug-resistance of Listeria monocytogenes ST8 in enoki mushrooms: Comparative genomic and phenotypic analysis with meat and clinical ST8 isolates.

Influence of different media and incubation times for determining the minimum inhibitory concentrations of gepotidacin, ciprofloxacin and ceftriaxone against Neisseria gonorrhoeae.

Newer methicillin-resistant antimicrobials are needed to address the rising prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative (MRCONS) infections. We describe two contrasting, recalcitrant staphylococcal infections successfully managed using early transition to the oral benzoquinolizine antibiotic alalevonadifloxacin, highlighting its utility in complex clinical settings. Two high-severitycases of staphylococcal infections are presented. Patient 1, a 58-year-old metastatic lung and orthopedic implant infectionon hemodialysis, developed catheter-associated MRSA sepsis with bacteremia, endocarditis, and metastatic lung and orthopedic implant infection. Patient 2, a 41-year-old male with a prior craniotomy, presented with a chronic cranial wound infection due to methicillin-resistant Staphylococcus hominis (MRCONS) originating from an infected ex vivo bone flap. Both patients initially received intravenous therapy and were transitioned to oral alalevonadifloxacin upon availability of susceptibility data. Levonadifloxacin susceptibility testing showed an MIC of 2 µg/mL for MRSA and 0.047 µg/mL for MRCONS-SCV. Patient 1 received 7 weeks of oral therapy aligned with POET recommendation for endocarditis, while Patient 2 completed 8 weeks of oral therapy consistent with OVIVA-based management of osteomyelitis. Despite significant challenges, both patients demonstrated rapid clinical improvement, resolution of infection, and no relapse during follow-up. These cases support oral alalevonadifloxacin as an effective and safe step-down option for complex MRSA and MRCONS infections, including endocarditis, osteomyelitis and meningitis. Alalevonadifloxacin (prodrug of levonadifloxacin) offers a promising oral treatment option when conventional agents are not suitable.

Genotypic diversity and zoonotic potential of Salmonella enterica from multiple hosts: implications for One Health.

Integrated genomic and phenotypic profiling of clinical Klebsiella pneumoniae reveals an ESBL-dominated, lineage-diverse hospital population.

The clinical challenge of Elizabethkingia infections: multidrug resistance, epidemiology, and management strategies.

Antibiotics are essential chemotherapeutic agents that inhibit or destroy pathogenic microorganisms, and their development from ancient natural remedies to the discovery of penicillin in 1928 revolutionized modern medicine. Multiple major classes, including β-lactam, macrolide, tetracycline, quinolone, aminoglycoside, sulfonamide, glycopeptide, and oxazolidinone, remain central to treating bacterial infections, making accurate assessment of their quality crucial. This review summarizes key analytical methods used for determining antibiotic potency and quantifying drug levels in pharmaceutical and biological matrices. Spectroscopic techniques provide simple and cost-effective evaluation, while chromatographic methods such as RP-HPLC, UPLC, TLC and HPTLC offer high sensitivity and specificity. Because chemical assays measure potency but not biological activity, critical microbiological parameters minimum inhibitory and bactericidal concentration, mutation-prevention concentration, and related indicators provide deeper insight into bacterial susceptibility and resistance mechanisms. The review also addresses the growing challenge of antimicrobial resistance, driven by misuse and overuse of antibiotics, and outlines current methodologies such as MIC, MBC, and susceptibility testing for detecting resistance across bacterial strains. Overall, the article emphasizes the need for integrated analytical and microbiological approaches to ensure accurate antibiotic evaluation and support effective therapeutic outcomes.

Early-life acquisition of antimicrobial resistance genes and strain-level genomic concordance across maternal-infant compartments.

Clinical characteristics, susceptibility profiles and treatment outcomes of pulmonary disease caused by Mycobacterium paraense.

Molecular epidemiology and genomic characterization of postpandemic macrolide-resistant Mycoplasma pneumoniae in hospitalized children.

Experimental evolution of enrofloxacin resistance and cross-resistance in Escherichia coli using a MEGA-plate system.

Co-occurrence and genetic basis of carbapenem and colistin resistance in multidrug-resistant gram-negative Bacilli.

Candida auris is an emerging yeast that is frequently resistant to antifungal drugs. C. auris can cause invasive infections associated with high mortality and can colonize patients asymptomatically, which facilitates transmission in health care settings. Since it was first reported in the United States in 2016, C. auris has been identified in multiple states, with increasing numbers of cases reported annually. Monitoring national trends in cases identified through clinical testing and screening for colonization is critical to guide infection prevention and control efforts. 2022-2024. State and jurisdictional health departments voluntarily report clinical and screening C. auris cases to CDC using standardized case definitions of the Council of State and Territorial Epidemiologists. Clinical cases are defined as detection of C. auris from specimens collected for diagnostic purposes; screening cases are defined as detection from colonization screening swabs. Cases were reported to CDC through the Research Electronic Data Capture (REDCap) or Data Collation and Integration for Public Health Event Response (DCIPHER) platforms. Data included patient age and sex, case type, specimen type (for clinical cases), health care facility type, Antimicrobial Resistance Laboratory Network geographic region, and specimen collection date. Analyses were descriptive and limited to cases with specimens collected during 2022-2024. During 2022-2024, a total of 13,507 clinical C. auris cases were reported to CDC, increasing from 2,882 in 2022 to 4,428 in 2023 and 6,197 in 2024, with smaller annual percentage increases over time (53.7% from 2022 to 2023 and 39.9% from 2023 to 2024). Most clinical cases occurred among adults aged ≥45 years (87.8%) and among males (61.0%). The most common specimen types among all clinical cases were urine (31.5%) and blood (30.2%); by year, the proportion of blood as the specimen type was 34.4% in 2022, 30.2% in 2023, and 25.6% in 2024. Most clinical cases were identified through specimens collected in acute care hospitals (76.6%) and long-term acute care hospitals (17.8%).During the same period, a total of 27,853 screening cases were reported to CDC, increasing from 6,226 in 2022 to 9,195 in 2023 and 12,432 in 2024. Screening cases most frequently occurred among adults aged ≥45 years (90.0%) and males (57.9%). Among cases with known facility type, the proportion of specimens collected in acute care hospitals increased from 24.7% in 2022 to 50.7% in 2024, whereas the proportion of specimens collected in long-term acute care hospitals decreased from 56.1% to 35.7% during the same period. The number of clinical and screening C. auris cases reported to CDC increased during 2022-2024, indicating ongoing transmission in U.S. health care settings. Although annual percentage increases in clinical cases declined over time, absolute case counts reported to CDC continued to rise. The increasing proportion of screening cases with specimens collected in acute care hospitals might reflect increased use of screening in acute care hospitals, including screening at admission. Because of increases in the number of reported C. auris cases, sustained infection prevention and control efforts in health care facilities, including adherence to transmission-based precautions, environmental disinfection with agents effective against C. auris, and communication of C. auris status during patient transfers remain essential to preventing clinical infections and colonization. Because this pathogen is frequently resistant to antifungal drugs, continued investment in laboratory capacity and surveillance, including antifungal susceptibility testing and screening of patients at high risk for C. auris infection, can support timely detection and guide prevention strategies. Ongoing public health coordination at federal, state, and local levels is critical to limit further spread and to address emerging antifungal drug resistance.

Metallo-β-lactamase (MBL)-producing Gram-negative bacteria pose a significant problem to antibiotic treatment due to their ability to inactivate most β-lactam antibiotics and resist inhibition by conventional β-lactamase inhibitors. While aztreonam-avibactam (ATM-AVI) has proven to be an effective treatment for these bacteria, previous reviews have been largely narrative, either from a microbiological perspective or a clinical perspective in isolation. This review seeks to provide a mechanism-based and translational synthesis of ATM-AVI by combining molecular antibiotic science, pharmacokinetic/pharmacodynamic (PK/PD) concepts, antimicrobial susceptibility testing, and clinical data. The mechanism of action of ATM-AVI is based on the natural stability of aztreonam to MBLs, resistance to co-produced serine β-lactamases by avibactam, and appropriate exposure strategies to ensure target attainment. There is consistent activity against MBL-producing Enterobacterales and Pseudomonas aeruginosa in surveillance and clinical trials, but emerging resistance due to PBP3 insertions, porin mutations, and efflux pump overexpression identifies important biological targets. The future clinical utility of ATM-AVI will depend on mechanism-based susceptibility testing, rapid diagnostic integration, and stewardship-driven use, particularly in high-prevalence settings. Beyond its current clinical utility, ATM-AVI provides insight into principles for the rational development and responsible use of next-generation antibiotics in the face of complex resistance.

We present a rare case of a 7-month-old infant with a complex invasive Streptococcus pneumoniae infection involving rib osteomyelitis, a pulmonary abscess, and a chest wall abscess. The patient presented with persistent fever and no respiratory symptoms. On day 9, chest radiography was performed because of persistent fever and marked leukocytosis, consistent with the American College of Radiology Appropriateness Criteria that recommend imaging in febrile infants with high fever (≥39°C) or elevated white blood cell counts (≥20 000/mm3). On day 14, the emergence of a chest wall mass prompted escalation to ultrasonography, which provided noninvasive assessment of soft tissue involvement. Subsequent contrast-enhanced computed tomography scans were undertaken to delineate the extent of contiguous spread, evaluate rib destruction, and exclude alternative diagnoses. Microbiological cultures of sputum and aspirated pus, along with metagenomic sequencing, confirmed the presence of macrolide-resistant S. pneumoniae. Because of benzylpenicillin and cephalosporin allergy, intravenous linezolid was selected, resulting in rapid clinical improvement. A 6-week course (intravenous infusion followed by oral) led to complete resolution on imaging, with no recurrence over 5years. This case underscores the importance of appropriate imaging modalities in febrile infants without respiratory symptoms and the need to consider extrapulmonary spread in chest wall masses. It highlights the diagnostic value of metagenomic sequencing and susceptibility testing in guiding individualized antimicrobial therapy, particularly in macrolide-resistant settings.

Antimicrobial resistance (AMR) in Enterobacteriaceae poses a critical threat to global health, particularly in regions where antibiotic misuse and limited surveillance prevail. Intensive care units (ICUs) act as focal points for resistance emergence and dissemination. This study aimed to evaluate long-term resistance trends among clinically significant Enterobacteriaceae isolated from two hospitals in North Lebanon (2016-2024). A retrospective analysis was conducted on 14,013 Enterobacteriaceae isolates obtained from Al Monla and Dar Al Shifa hospitals between 2016 and 2024. Identification was achieved using biochemical testing or MALDI-TOF mass spectrometry, and susceptibility testing followed EUCAST standards. No molecular characterization of resistance genes was performed. Data were analyzed using SPSS v23.0, applying Chi-square or Fisher's exact tests (p < 0.05). Among 14,013 isolates, Escherichia coli (E. coli) was predominant (66.4%), followed by Klebsiella pneumoniae (K. pneumoniae) (12.4%), Proteus mirabilis (P. mirabilis) (5.5%), and Enterobacter cloacae (E. cloacae) (3.7%). Overall, β-lactam resistance remained widespread across species. In E. coli, carbapenem non-susceptibility increased from 2.7% to 4.8% (p < 0.001). P. mirabilis and E. cloacae exhibited significant increases in ESBL production (p = 0.006 and p = 0.007, respectively). K. pneumoniae showed fluctuating resistance trends with a mild decline in carbapenem resistance (p = 0.029). ICU isolates demonstrated higher ESBL and MDR rates than non-ICU isolates (p < 0.01), and hospital-acquired infections showed significantly higher resistance across most drug classes compared to community-acquired cases (p < 0.05). Over the 9-year study period, Enterobacteriaceae isolates in North Lebanon demonstrated persistently high β-lactam resistance and increasing carbapenem non-susceptibility, particularly in E. coli. These findings underscore the importance of ongoing AMR surveillance and provide regional data that may support future evidence-based clinical and public health decision-making.

Diagnostic accuracy of short-incubation cultures versus standard protocols for bacterial identification and susceptibility testing via VITEK® MS and VITEK®2 XL.

Culture-proven osteoarticular mycoses: An eight-year single-center descriptive study of fungal distribution and antifungal susceptibility trends.

Background: Certain bacteria present in beverage can lead to foodborne and waterborne disease. Therefore, the development of a low-cost, portable, and user-friendly bacterial detection tool is essential. Objectives: This study aimed to evaluate the sensitivity and specificity of the simplified miniaturized MPN (mMPN) method compared to standard procedures, including MPN and TPC. Methodology: In this study, we developed a simplified kit for bacterial enumeration in beverage, and tested the sensitivity and specificity using 28 samples. Results: The kit demonstrated a sensitivity of 84.6%, specificity of 100%, and a Cohen’s Kappa coefficient of 0.845 when compared with the Total Plate Count method, indicating an almost perfect agreement. When compared to the Total coliform method using Most Probable Number (MPN), the kit showed a sensitivity of 69.2%, specificity of 93.3%, and a Cohen’s Kappa coefficient of 0.635, indicating substantial agreement. Bacterial growth in broth medium was further confirmed using MacConkey agar. Biochemichal identification through the VITEK® 2 Compact system revealed that 5 out of 7 isolates were identified as Acinetobacter baumannii, and 2 out of 7 were identified as Moraxella species. It has been reported that some beverages contain pathogenic bacteria, also antimicrobial resistant feature. Antimicrobial susceptibility testing indicated that none of the isolates were resistant. Furthermore, all isolates exhibited low virulence in Omphisa fuscidentalis, used as an in vivo animal model. Conclusion: According to the results, we concluded that this modified detection kit is reliable enough in terms of specificity and sensitivity compared to standard method, in particular for low-cost testing.

Whole-genome characteristics, antimicrobial resistance and virulence of pathogenic Aeromonas veronii from diseased Macrobrachium rosenbergii.