Journal of Clinical Microbiology最新文献

{"title":"Paradoxical carbapenemase activity detected by modified carbapenemase inactivation (mCIM) method in <i>Citrobacter sedlakii</i>.","authors":"D Garrett Brown, Matthew Surette, Sreejana Ray, Kevin Guo, Reagan Chan, Liusheng Huang, Sanchita Das","doi":"10.1128/jcm.00589-25","DOIUrl":"https://doi.org/10.1128/jcm.00589-25","url":null,"abstract":"<p><p>Screening for carbapenemase-producing Enterobacterales is a necessity for hospitals serving high-risk patient populations. Detection methods often incorporate the modified carbapenemase inactivation method (mCIM) test to verify carbapenemase production in suspect isolates. Here, we demonstrate the case of a <i>Citrobacter sedlakii</i> isolate recovered from carbapenemase-surveillance culture that was strongly mCIM positive for carbapenemase production, but phenotypically nonresistant to carbapenems. The modified carbapenemase inactivation method with EDTA (eCIM) test, which suggests the presence of a metallo-β-lactamase, was positive as well. Liquid chromatography mass spectrometry additionally confirmed the loss of meropenem during the mCIM test. Whole-genome sequencing detected only the presence of the chromosomal class A serine β-lactamase SED-1 but did not identify any known carbapenemase or additional β-lactamases. Further characterization suggested that the large inoculum utilized in mCIM tests can give the impression of carbapenemase production in non-resistant isolates. Additionally, the large inoculum, combined with weak carbapenemase activity, can mimic the phenotype expected for metallo-β-lactamase in the eCIM test. These results suggest that utilization of the mCIM and eCIM tests without appropriate susceptibility testing can lead to erroneous detection of carbapenemase production.IMPORTANCEPhenotypic tests including the mCIM are often used for detection of carbapenemase production in Enterobacterales. The presence of a carbapenemase gene is confirmed by PCR assays and, while rarely seen, a positive mCIM assay and negative PCR can alert the laboratory to the presence of rare carbapenemases (such as GES and IMI). We report a false-positive mCIM test, which we demonstrate is due to the heavy inoculum of the organism used in the assay. Whole-genome sequencing showed that a class A β-lactamase (<i>bla_SED-1</i>) was present, and mass spectrometry demonstrated degradation of meropenem during the mCIM assay. The inoculum effect should be considered when interpreting mCIM and eCIM assays where a carbapenemase gene is not detected.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0058925"},"PeriodicalIF":5.4,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxford Nanopore Technologies R10 sequencing enables accurate cgMLST-based bacterial outbreak investigation of <i>Neisseria meningitidis</i> and <i>Salmonella enterica</i> when accounting for methylation-related errors.","authors":"Bert Bogaerts, Margo Maex, Florian Commans, Nathalie Goeders, An Van den Bossche, Sigrid C J De Keersmaecker, Nancy H C Roosens, Pieter-Jan Ceyssens, Wesley Mattheus, Kevin Vanneste","doi":"10.1128/jcm.00410-25","DOIUrl":"https://doi.org/10.1128/jcm.00410-25","url":null,"abstract":"<p><p>Core-genome multi-locus sequence typing (cgMLST) is a well-established and standardized method for genomics-based cluster detection and phylogenomic analysis of bacteria. The reduced error rate of Oxford Nanopore Technologies (ONT) R10 sequencing has prompted many laboratories to explore incorporating this technology into their activities. However, conflicting reports exist on the performance of ONT R10 sequencing for cgMLST analysis. This study evaluates the suitability of ONT R10 data for cgMLST allele calling and cluster detection for bacterial outbreak investigation. ONT and Illumina sequencing data were generated for 24 <i>Neisseria meningitidis</i> and 24 <i>Salmonella enterica</i> isolates. For ONT, both the rapid barcoding kit (RBK) and the rapid PCR barcoding kit (RPB) were used. The percentage of loci called in the ONT-only assemblies was very high for both species. However, the proportion of mismatched alleles to the hybrid assemblies was substantially higher for the <i>Neisseria</i> ONT-only assemblies with the RBK kit, resulting in incorrect cluster assignments. The large majority of these mismatched alleles were due to incorrect base calls at methylated positions, which did not affect the ONT data generated using the RPB kit or any of the <i>Salmonella</i> ONT-only assemblies. In conclusion, ONT R10 sequencing shows great potential as a viable method for cgMLST analysis, but methylation-related errors can affect performance for certain species and strains. When properly corrected for, ONT R10 had the same performance for cgMLST analysis as Illumina, and both could be used interchangeably. These results support the integration of ONT R10 sequencing into routine public health and clinical workflows.</p><p><strong>Importance: </strong>This study evaluates the suitability of Oxford Nanopore Technologies R10 sequencing for core-genome multi-locus sequence typing (cgMLST), a widely used method in (clinical) outbreak investigation and bacterial strain tracking. We have sequenced 24 <i>Neisseria meningitidis</i> and 24 <i>Salmonella enterica</i> strains, including confirmed outbreak cases, using Illumina and ONT R10 sequencing to evaluate the performance for cgMLST analysis. We used a PCR-based and native barcoding protocol for the ONT sequencing, which enabled us to demonstrate a substantial species-dependent impact of methylation-related errors on the performance. However, we demonstrate that when these errors are properly addressed, ONT R10 can be used for accurate cgMLST-based clustering, including integration with strains sequenced using Illumina. Our findings support the use of ONT R10 as an alternative to Illumina sequencing for cgMLST analysis in routine public health practice.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0041025"},"PeriodicalIF":5.4,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An underestimated pathogen: <i>Corynebacterium</i> species.","authors":"Brooks I Mitchell, John E Markantonis","doi":"10.1128/jcm.01552-24","DOIUrl":"https://doi.org/10.1128/jcm.01552-24","url":null,"abstract":"<p><p><i>Corynebacterium</i> species are a diverse group of organisms historically considered to be non-pathogenic, outside of the <i>C. diphtheriae</i> complex. Over the last few decades, this belief has been disproven with many notable non-diphtheriae <i>Corynebacterium</i> species being found to be pathogenic, often in certain clinical scenarios and/or anatomical sites. <i>C. striatum</i> and <i>C. jeikeium</i> are responsible for a large portion of bloodstream infections and orthopedic infections related to coryneform Gram-positive rods (GPRs). Eye and ear infections have commonly been attributed to <i>C. macginleyi</i> and <i>C. otitidis</i>, respectively. Pneumonia in critically ill and immunosuppressed individuals has been frequently reported by the <i>C. propinquum</i>/<i>pseudodiphtheriticum</i> group and occasionally in <i>C. striatum. C. urealyticum</i> is the primary pathogen associated with encrusted cystitis. Granulomatous lobular mastitis and breast abscesses have a strong association with <i>C. kroppenstedtii</i>. Erythrasma (<i>C. aurimucosum</i>/<i>minutissimum</i> group), trichobacteriosis (<i>C. flavescens</i>), and hidradenitis suppurativa are cutaneous disorders caused by or associated with <i>Corynebacterium</i> species. Biofilm formation by these bacteria leads to hardware/medical device-associated infections involving endovascular catheters, cerebrospinal fluid shunts, peritoneal dialysis catheters, and prosthetic joints. Clinical microbiology laboratories must be aware of this and optimize laboratory identification and reporting of these organisms when appropriate. Matrix-associated laser/adsorption ionization time-of-flight mass spectrometry, currently available in most large clinical microbiology laboratories, offers laboratories the ability to rapidly, accurately, and affordably accomplish this task.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0155224"},"PeriodicalIF":5.4,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144955957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance and workflow comparison of the VITEK MS PRIME and Bruker Biotyper MALDI-TOF MS systems.","authors":"Rachel E Bosserman, Nicole J Tarlton, Kelly Alvarado, Brittany Roemmich, Melanie L Yarbrough","doi":"10.1128/jcm.00211-25","DOIUrl":"10.1128/jcm.00211-25","url":null,"abstract":"<p><p>Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is widely used for rapid identification of bacteria and yeast in clinical labs. The VITEK MS PRIME (\"PRIME\") is the latest MALDI-TOF MS system from bioMérieux. This study evaluated PRIME's performance and workflow timing against the MALDI Biotyper CA System by Bruker (\"Biotyper\"). We compared a collection of 154 bacteria and yeast clinical isolates from various specimen types using three methods: Biotyper target with a toothpick, PRIME target with the PICKME nib, and PRIME target with a loop. Positive blood culture isolates were also analyzed using these methods, with high-experience (HEU, <i>n</i> = 300) and low-experience users (LEU, <i>n</i> = 50) after short (6-8 h) and routine (18-24 h) incubation on agar plates. Workflow timing, from sample processing to organism identification, was assessed to identify time savings. PRIME identified 96% (PICKME) and 95% (Loop) of challenge isolates to genus level, compared with Biotyper at 99%. Short incubation of positive blood culture isolates demonstrated similar species-level identification rates across all methods (Biotyper: 84%, PRIME PICKME: 80%, PRIME Loop: 81%), although more repeats were needed compared with routine incubation. No difference in species identification occurred between users for any method at short incubation (89%-91%, HEU, vs 79%-85% LEU). Single-target process times were comparable for all methods (55-59 min), whereas PRIME methods had shorter hands-on times for analysis of multiple targets (Biotyper: 53 min, PRIME PICKME: 39 min, PRIME Loop: 40 min). These findings highlight the comparable performance of the PRIME and Biotyper systems while demonstrating the potential for time savings with PRIME workflows, particularly in high-throughput settings.IMPORTANCEThis study provides a critical evaluation of the new VITEK MS PRIME MALDI-TOF MS system, comparing its performance and workflow efficiency against the Bruker MALDI Biotyper. The study investigates the success rate of isolate identification from short incubation of positive blood cultures, illustrating the utility of this technique for downstream workflows such as faster reporting of results for patient management and isolate identification for interpretation of rapid phenotypic AST. Analysis of different workflows demonstrated areas for potential time savings, particularly in high-throughput settings. These findings highlight the importance of optimizing MALDI-TOF MS workflows in the era of workforce shortages and lab centralization to enhance rapid pathogen identification and improve patient care.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0021125"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345239/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144333166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Re-evaluation of penicillin and ceftriaxone MIC results to predict susceptibility to the oral cephalosporin, cefpodoxime, in <i>Streptococcus pneumoniae</i> clinical isolates from the United States according to CLSI guidelines (2019-2021).","authors":"Rodrigo E Mendes, Jessica V Pierce, Kelly Wright, Michael D Huband, Mariana Castanheira","doi":"10.1128/jcm.00027-25","DOIUrl":"10.1128/jcm.00027-25","url":null,"abstract":"<p><p>Clinical and Laboratory Standards Institute (CLSI) M100Ed24 (2024) states that <i>Streptococcus pneumoniae</i> susceptible to oral penicillin can be considered susceptible to various β-lactams, including oral cephalosporins. However, surrogacy guidance is not available for isolates nonsusceptible to oral penicillin. Instead, such isolates require specific MIC testing and interpretations for reporting susceptibility to oral cephalosporins, for which susceptibility testing is limited in most automated systems, and consequently restricts information pertaining to oral cephalosporins at an individual institution. This study evaluated the ability of the penicillin breakpoints to predict cefpodoxime and ceftriaxone susceptibilities against a recent collection of <i>S. pneumoniae</i> from United States hospitals according to CLSI guidelines. The susceptible breakpoint for oral penicillin (≤0.06 mg/L) predicted susceptibility to cefpodoxime and ceftriaxone. However, when isolates were nonsusceptible to oral penicillin (MIC, >0.06 mg/L), susceptibility to cefpodoxime could not be predicted due to a low categorical agreement (CA) (78.4%). Parenteral penicillin breakpoints also could not predict cefpodoxime susceptibility due to the elevated number of very major errors and a CA of 76.8%; however, these breakpoints could still be used as a surrogate marker to predict ceftriaxone susceptibility. Finally, ceftriaxone could be used for surrogate testing of cefpodoxime by applying breakpoints (≤0.25 mg/L for susceptible; 0.5 mg/L for intermediate; ≥1 mg/L for resistant) lower than the current clinical cutoffs. These analyses showed that isolates nonsusceptible to oral penicillin cannot be considered susceptible to cefpodoxime, and caution should be used when prescribing oral cephalosporins for the empiric treatment of community-acquired bacterial pneumonia.IMPORTANCESusceptibility results to oral cephalosporins are rarely available to guide therapy due to the limited number of drugs evaluated on common automated antimicrobial susceptibility testing (AST) systems (i.e., Vitek 2, MicroScan, and Phoenix). In addition, disk diffusion methods for determining <i>Streptococcus pneumoniae</i> susceptibility to β-lactam agents are not reliable, and a quantitative method, such as broth microdilution or gradient strips, is required. In addition, the epidemiology and serotypes of <i>S. pneumoniae</i> are constantly evolving; therefore, this work provides a re-evaluation of surrogacy testing for β-lactam agents against <i>S. pneumoniae</i> recently recovered from United States laboratories. The data provide the possible use of ceftriaxone MIC for determining cefpodoxime susceptibility. This should be of interest to microbiology laboratories and the scientific community.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0002725"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345151/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144475472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of plasma cell-free DNA PCR for non-invasive diagnosis of mucormycosis.","authors":"Jordan Mah, Anthony Lieu, Veronica Nicholas, Angel Moreno, Kanagavel Murugesan, Indre Budvytiene, Niaz Banaei","doi":"10.1128/jcm.00796-25","DOIUrl":"10.1128/jcm.00796-25","url":null,"abstract":"<p><p>Diagnosis of mucormycosis poses a substantial challenge due to the lack of a non-invasive biomarker and limitations of conventional diagnostics using invasive specimens. The aim of this study was to characterize the performance of Mucorales plasma cell-free DNA (cfDNA) PCR in immunosuppressed and non-immunosuppressed patients with pulmonary, disseminated, and localized mucormycosis. Patients with Mucorales plasma cfDNA test results were retrospectively categorized as proven or probable for sensitivity analysis and as no Mucorales infection for specificity analysis. In total, 85 positive and 212 negative Mucorales plasma cfDNA test results in unique patients were included in this study. Per the expert definitions, 47 patients had proven or probable mucormycosis, and 171 did not have invasive Mucorales infection. The Mucorales plasma cfDNA PCR had an overall sensitivity and specificity of 85.1% (40/47, 95% CI, 71.7-93.8) and 92.9% (158/170, 95% CI, 88.0-96.3), respectively. The sensitivity was 92.1% (35/38, 95% CI, 78.6-98.3) and 55.6% (5/9, 95% CI, 21.2-86.3) in patients with and without immunosuppression, respectively, and 100% (14/14, 95% CI, 76.8-100), 89.5% (17/19, 95% CI, 66.9-98.7), and 64.3% (9/14, 95% CI, 35.1-87.2) in patients with disseminated, pulmonary, and localized mucormycosis, respectively. Mucorales plasma cfDNA PCR is a sensitive and specific non-invasive testing modality for the diagnosis of mucormycosis in immunosuppressed patients and those with pulmonary and disseminated infection.IMPORTANCEMucormycosis is an invasive mold infection associated with high morbidity and mortality. Early diagnosis and effective antifungal treatment are critical for improving clinical outcomes. However, diagnosis of mucormycosis is often delayed due to the lack of a non-invasive biomarker and insensitivity of culture and non-specificity of histopathology performed on invasive specimens. Mucorales plasma cell-free DNA (cfDNA) PCR is a novel testing modality that allows non-invasive diagnosis of mucormycosis. In the current study, we evaluated the clinical performance of a pre-analytically optimized Mucorales plasma cfDNA PCR in immunosuppressed and non-immunosuppressed patients with pulmonary, disseminated, and localized infections. We show that Mucorales plasma cfDNA PCR is highly sensitive and specific in immunosuppressed patients with pulmonary and disseminated infections. Thus, the Mucorales plasma cfDNA PCR represents an accurate diagnostic tool for non-invasive diagnosis of mucormycosis, which may enable early treatment and improved outcomes in immunosuppressed patients with mucormycosis.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0079625"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345248/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144591308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First description of the performance of the VITEK MITUBE device used with MALDI-TOF mass spectrometry to achieve identification of gram-negative bacteria directly from positive blood culture broth.","authors":"Daniel D Rhoads, Nancy D Hanson, Kaley Reedy, Johanne Gafsi, Yun X Ying, Dwight J Hardy","doi":"10.1128/jcm.00122-25","DOIUrl":"10.1128/jcm.00122-25","url":null,"abstract":"<p><p>Improving the rapidity of identification of bacteria causing bacteremia continues to be a focus for quality improvement within the discipline of clinical microbiology. This multicenter study was used to obtain In Vitro Diagnostic Regulation Conformite Europeenne (CE) mark in Europe and describes the performance of the VITEK MITUBE to matrix-assisted laser desorption/ionization (MALDI) workflow for identification of 10 species of gram-negative bacteria directly from positive blood culture broth without subculture. One hundred twenty-five (125) prospective clinical samples, including <i>Escherichia coli</i> (69), <i>Klebsiella aerogenes</i> (4), <i>Klebsiella oxytoca</i> (3), <i>Klebsiella pneumoniae</i> (29), <i>Proteus mirabilis</i> (9), <i>Pseudomonas aeruginosa</i> (10), and <i>Serratia marcescens</i> (1), were included; and 123 (98.4%) were accurately identified using the VITEK MITUBE workflow. None were misidentified, and two (1.6%) <i>K. pneumoniae</i> were not identified. Contrived samples were also tested and reported in this study. When considering both the prospective clinical samples and the contrived samples, the workflow was able to identify the species 95% of the time. <i>Proteus vulgaris</i> accounted for 81% (13/16) of the samples that were unable to achieve an identification. A single misidentification error is reported in the contrived sample testing. The VITEK MITUBE to MALDI workflow enables accurate and reliable identification of commonly encountered gram-negative bacteria directly from positive blood culture broth.IMPORTANCEMITUBE is a new <i>in vitro</i> diagnostic device designed to meet a need in the clinical microbiology community for a simple, rapid, accurate, and inexpensive system to identify bacteria detected in blood cultures using MALDI-TOF and without the need for subculture.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0012225"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345195/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144659367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CDC dengue typing kit fails to detect dengue virus 2 sylvatic genotype.","authors":"Diamilatou Balde, Mignane Ndiaye, Agathe Shella Efire, Ousmane Faye, Amadou Alpha Sall, Manfred Weidmann, Oumar Faye, Idrissa Dieng","doi":"10.1128/jcm.01741-24","DOIUrl":"10.1128/jcm.01741-24","url":null,"abstract":"","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0174124"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345212/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144659364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the MIC test strips for antifungal susceptibility testing of <i>Candidozyma auris</i> (<i>Candida auris</i>) using a representative international collection of isolates.","authors":"Maria Siopi, Sevasti Leventaki, Ioannis Pachoulis, Bram Spruijtenburg, Jacques F Meis, Spyros Pournaras, Georgia Vrioni, Athanasios Tsakris, Joseph Meletiadis","doi":"10.1128/jcm.00399-25","DOIUrl":"10.1128/jcm.00399-25","url":null,"abstract":"<p><p>We compared MIC test strips (MTS) with the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution method using an international panel of 100 <i>Candidozyma auris</i> (<i>Candida auris</i>) isolates belonging to different clades. The agreement (±1 twofold dilution) between the methods and the categorical agreement (CA) based on the Centers for Disease Control and Prevention's (CDC's) tentative resistance breakpoints and MTS-specific wild-type upper limit values (WT-ULVs) were determined. The MTS-CLSI agreement was poor to weak for posaconazole (3%), itraconazole (20%), voriconazole (31%), and 5-flucytosine (37%), and moderate to strong for isavuconazole (58%), anidulafungin (68%), caspofungin (72%), micafungin (77%), and amphotericin B (85%). Most fluconazole MICs were off-scale, precluding a corresponding estimation. Significant interpretation discrepancies were recorded using the CDC's breakpoints for amphotericin B (66% CA, 34% major errors; MaEs), but not for fluconazole (98% CA, 1% MaEs, 1% very major errors; VmEs), anidulafungin (97% CA, 3% MaEs, 0% VmEs), micafungin (99% CA, 1% MaEs, 0% VmEs), and caspofungin (95% CA, 5% MaEs, 0% VmEs). Discrepancies were minimized using the amphotericin B method-specific WT-ULV of 4 mg/L (98% CA, 2% MaEs). The MTS-specific WT-ULVs of echinocandins could help to detect 100% of <i>FKS1</i> mutants. MTS generated higher MICs than the CLSI for azoles and 5-flucytosine. MTS could accurately detect fluconazole and echinocandin resistance among <i>C. auris</i> isolates. Nevertheless, it overestimated amphotericin B resistance as per the CDC's breakpoint of 2 mg/L. This can be improved by using the MTS-specific WT-ULV of 4 mg/L.IMPORTANCE<i>Candidozyma auris</i> (<i>Candida auris</i>) may exhibit resistance to multiple and sometimes even all currently available classes of antifungals. Hence, antifungal susceptibility testing (AFST) is of key importance to guide the clinician in therapeutic decision-making and to detect novel patterns of resistance. Gradient diffusion strips, referred to both Etest and MIC test strip (MTS), are broadly used in laboratory routine for AFST of yeasts. We therefore compared MTS with the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution method using an international panel of 100 <i>C</i>. <i>auris</i> isolates belonging to different clades. Significant interpretation discrepancies were recorded for amphotericin B (66% categorical agreement, 34% major errors), which could be minimized using the amphotericin B method-specific wild-type upper limit value of 4 mg/L. MTS generated higher MICs than the CLSI for azoles and 5-flucytosine. MTS could accurately detect fluconazole and echinocandin resistance.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0039925"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345157/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144553626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sulbactam-durlobactam in combination with aztreonam and carbapenems against carbapenem-resistant <i>Acinetobacter baumannii</i>: an assessment using the MIC-based broth disk elution.","authors":"C Koenig, D P Nicolau, T E Asempa","doi":"10.1128/jcm.00709-25","DOIUrl":"10.1128/jcm.00709-25","url":null,"abstract":"","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0070925"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345227/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144698697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}