Other specific DSP article suggested by Editorial Board
Evaluation of EUCAST Rapid Antimicrobial Susceptibility Testing for Gram-Negative Bacteria Directly from Positive Blood Cultures.
DOI: 10.2147/IDR.S514981
Authors: Tian PP et al
Abstract
Purpose: This study aims to evaluate the accuracy of EUCAST rapid antimicrobial susceptibility testing (RAST) for Gram-negative bacteria directly from positive blood cultures, comparing it with short-term incubation (5-7 hours) and conventional broth microdilution methods.
Methods: A total of 139 Gram-negative isolates were tested. RAST results were assessed at 4 h, 6 h against minimal inhibitory concentration results using the short-term incubation (5-7 h) method, while at 16-20 h, the RAST results were compared to conventional method. For those with interpretable results, CLSI M52 was used to define cutoffs for equivalence in antimicrobial susceptibility testing.
Results: Among all isolates, 80.6% (112/139) were successfully interpreted based on EUCAST RAST breakpoints, including Escherichia coli (81), Klebsiella pneumoniae complex (17), Pseudomonas aeruginosa (10) and Acinetobacter baumannii (4). The overall category agreements for all tested antibiotics were 98.9%, 99.5%, and 99.7% at 4, 6, and 16-20 hours, respectively, for E. coli, and 100% for K. pneumoniae, P. aeruginosa, and A. baumannii. The area of technical uncertainty rate significantly decreased over time, from 9.1% at 4 hours to 3.1% at 16-20 hours (p < 0.05). The method effectively identified extended-spectrum beta-lactamase (ESBL)-producing and carbapenem-resistant bacteria, demonstrating performance comparable to the BD system. Additionally, results for other Enterobacterales could be interpreted using the RAST breakpoints for E. coli. The integration of RAST into routine workflows provides rapid and accurate results without incurring additional costs or labor.
Conclusion: RAST is a reliable and cost-effective method for testing Gram-negative bacteria directly from blood cultures, significantly reducing turnaround time. Utilizing RAST at various reading times (6 hours and 16-20 hours) optimizes clinical workflows, enhances antimicrobial stewardship, and improves patient outcomes.
Other specific DSP article suggested by Editorial Board
Comparative Epidemiology and Resistance Mechanisms of Carbapenem-, Tigecycline-, and Polymyxin-Resistant Enterobacteriaceae in Pediatric Diarrhea, 2017 and 2023.
Authors: Zhang J et al
Abstract
The increasing prevalence of antimicrobial resistance (AMR) infections in children is becoming a growing global concern. AMR poses a significant challenge in pediatric diarrhea, where multidrug-resistant Enterobacteriaceae threaten treatment efficacy. This study investigates the prevalence, resistance mechanisms, and genetic characteristics of carbapenem-, tigecycline-, and polymyxin-resistant Enterobacteriaceae isolated from pediatric diarrhea cases , in 2017 (n=1059) and 2023 (n=367). The prevalence of mcr-1-positive strains declined significantly from 2.36% (25/1059) in 2017 to 0.82% (3/367) in 2023, while tet(X4)-positive strains rose from 0% to 1.91% (7/367). Carbapenemase-producers remained rare (0.28% in 2017; 1.63% in 2023), with blaNDM as the dominant carbapenemase gene. Whole genome sequencing revealed diverse antimicrobial resistance genes (ARGs) and evolving plasmid types. Notably, by 2023 all mcr-1 were carried on IncI2 plasmids. Conjugation experiments confirmed plasmids carrying mcr-1, blaNDM-5, and tet(X4) are transferable to a recipient strain, highlighting the potential for horizontal gene transfer. Our findings demonstrate a significant shift in pediatric diarrhea-associated Enterobacteriaceae resistance profiles from 2017 to 2023. The decline in mcr-1 mirrors the impact of reduced polymyxin use, whereas the rise of tet(X4) signals a new challenge. These findings underscore the dynamic nature of AMR in pediatric Enterobacteriaceae and emphasize the need for stringent antimicrobial stewardship and surveillance. A One Health approach, integrating clinical, agricultural, and environmental efforts, is crucial to mitigating AMR spread and protecting pediatric health globally.
Other specific DSP article suggested by Editorial Board
Beyond guidelines: what do I need to know when dealing with fungal diagnostics?
Authors: Lass- Florl C et al
Abstract
Background: Diagnosing invasive fungal infections (IFIs) is notoriously challenging. Test sensitivity and specificity vary with fungal burden, overlapping microscopic fungal appearances, lack of quantitative culture thresholds and, above all, the patient’s immune status, specimen quality and prior antifungal exposure. These variables can mask or mimic disease, leading to delayed or erroneous treatment decisions.
Objective: To distil the practical, “”beyond-guideline”” insights that clinicians and laboratorians need for reliable IFI diagnosis, and to outline a context-driven approach that complements existing recommendations.
Sources: Narrative synthesis of PubMed-indexed literature on fungal diagnostics published chiefly between 2020 – 2025, augmented by current global guidelines from ECMM/ISHAM/ASM and selected landmark papers outside this window when foundational.
Content: The review explains how (i) host immune state (neutropenia, AIDS, corticosteroid use) skews antigen-versus-antibody performance; (ii) specimen choice (BAL, blood, CSF, tissue) and site of disease dictate test yield; (iii) pre-emptive or empiric antifungals suppress culture and antigen signals yet may leave PCR positive (iv) cross-reactivity (e.g., β-D-glucan with bacteremia, galactomannan with Fusarium); and mixed infections cloud interpretation; and (v) colonisation must be separated from invasion through combined microbiology, and clinical risk assessment. Traditional microscopy/culture, antigen assays, PCR and emerging next-generation sequencing are compared across major pathogen groups, with tables summarising sensitivities, specificities and pitfalls.
Implications: Applying an approach that layers multiple modalities according to patient risk and specimen type can shorten time-to-diagnosis, reduce false negatives/positives and enable earlier targeted therapy. Integrating these context-aware steps into routine practice and future guideline updates is likely to improve IFI outcomes and optimise antifungal stewardship.”
Other specific DSP article suggested by Editorial Board
First Report from Colombia of a Urinary Tract Infection Caused by Kluyvera ascorbata Exhibiting an AmpC Resistance Pattern: A Case Report.
Authors: Artunduaga-Canas E et al
Abstract
Background: Urinary tract infections represent a significant healthcare burden, particularly among vulnerable patients with chronic comorbidities. In this case report, we describe a UTI caused by Kluyvera ascorbata exhibiting an AmpC resistance pattern in an 85-year-old male with stage IV chronic kidney disease and a history of ESBL-positive infection.
Methods: A comprehensive diagnostic workup was performed, including clinical evaluation, laboratory tests (urinalysis, complete blood count, renal function tests), and microbiological cultures with antibiogram analysis using the MicroScan WalkAway (Beckman Coulter, Brea, United States) and VITEK2 Compact systems (bioMérieux, Marcy L’Étoile or Craponne, France).
Results: The initial urine culture revealed a Gram-negative bacillus and subsequent identification confirmed K. ascorbata, which demonstrated resistance to ampicillin and cefazolin while remaining susceptible to meropenem. The patient received intravenous meropenem therapy for 10 days, resulting in clinical improvement and a subsequent negative urine culture.
Conclusions: This case reports a complicated urinary tract infection caused by K. ascorbata with an AmpC resistance pattern, highlighting the importance of considering this infrequently reported pathogen and its resistance profile in vulnerable patients. Its multidrug-resistant profile underscores the necessity for vigilant antimicrobial stewardship and further research to develop standardized treatment protocols for managing infections caused by this organism.
Other specific DSP article suggested by Editorial Board
A Nomogram to Predict Bloodstream Infections Caused by Third-Generation Cephalosporin-Resistant Enterobacteriaceae.
Authors: Liu CL et al
Abstract
Background: Third-generation cephalosporin resistance (3GCR) in Enterobacteriaceae bloodstream infections (BSIs) challenges clinical management in China. This study aimed to develop a predictive tool to guide antibiotic stewardship.
Methods: A retrospective cohort of 459 patients with Enterobacteriaceae BSIs (185 3GCR, 274 third-generation cephalosporin-sensitive [3GCS]) from a tertiary hospital (2021-2023) was analyzed. Multivariate logistic regression with backward selection identified predictors, integrated into a nomogram.
Results: Independent 3GCR predictors included advanced age ( (Odds Ratio (OR)=1.02, 95% Confidence Interval (CI):1.01-1.04), liver cirrhosis (OR=2.18, 1.26-3.77), solid tumors (OR=2.04, 1.19-3.50), prior third-generation cephalosporin use (OR=2.44 1.47-4.08), and elevated procalcitonin (OR=1.01, 1.01-1.02). The nomogram showed moderate discrimination (Area Under Curve (AUC)=0.751, 95%CI:0.67-0.83) and good calibration (Hosmer-Lemeshow P=0.757).
Conclusions: This nomogram, incorporating readily available clinical variables, facilitates rapid 3GCR risk stratification. Its implementation may optimize empirical antibiotic selection, improve outcomes, and mitigate resistance escalation in Enterobacteriaceae BSIs.
Other specific DSP article suggested by Editorial Board
The Global Challenge of Antimicrobial Resistance: Mechanisms, Case Studies, and Mitigation Approaches
DOI: 10.1002/hsr2.71077
Authors: Nazir A et al
Abstract
Background and aims: Antimicrobial resistance (AMR) is projected to cause 10 million deaths annually by 2050 if left unaddressed, posing a severe threat to global health and modern medicine. This review analyzes the molecular and ecological mechanisms underlying antibiotic resistance and evaluates global efforts aimed at containment to identify actionable strategies to mitigate AMR’s escalating impact.
Methods: A systematic literature review was performed using databases including PubMed, ScienceDirect, Scopus, Google Scholar, and Web of Science, focusing on peer-reviewed studies from 2000 to 2024. Search terms included “”antibiotic resistance,”” “”resistance mechanisms,”” “”horizontal gene transfer,”” and “”AMR epidemiology.”” A total of 152 articles were selected based on predefined inclusion criteria relevant to resistance mechanisms, epidemiological data, clinical outcomes, and public health interventions.
Results: Findings underscore three dominant resistance pathways: target site modification, enzymatic degradation (e.g., β-lactamases), and horizontal gene transfer via plasmids and transposons. Notably, resistance to last-resort antibiotics (e.g., colistin, carbapenems) is rising in pathogens such as Klebsiella pneumoniae and Acinetobacter baumannii, with treatment failure rates exceeding 50% in some regions. Surveillance gaps and unregulated antibiotic use, especially in LMICs, further accelerate resistance spread. Only a limited number of new antibiotic classes have been approved since 2010, underscoring the innovation gap.
Conclusion: AMR is a quantifiable, escalating crisis that undermines decades of progress in infectious disease control. Tackling it requires coordinated action: strengthening antimicrobial stewardship, incentivizing antibiotic R&D, integrating environmental and clinical surveillance under One Health frameworks, and implementing global policy reforms. Without prompt action, AMR could surpass cancer in annual mortality by mid-century.”