Journal of Clinical Microbiology最新文献

{"title":"Toward diagnostic preparedness: detection of highly pathogenic avian influenza A(H5N1) in contrived nasal swab specimens using rapid antigen and point-of-care molecular tests.","authors":"Leda Bassit, Gregory L Damhorst, Heather B Bowers, Courtney Sabino, Julie Sullivan, Emily B Kennedy, Jacob Khouri, Pamela Miller, Eric Lai, Raymond F Schinazi, Wilbur A Lam, Nira R Pollock, Anuradha Rao","doi":"10.1128/jcm.00548-25","DOIUrl":"10.1128/jcm.00548-25","url":null,"abstract":"<p><p>Highly pathogenic avian influenza (HPAI) A(H5N1) clade 2.3.4.4b was first detected in birds in 2021 in the United States (U.S.). An ongoing outbreak in dairy cattle began in early 2024 involving genotype B3.13. At least 70 U.S. cases have been identified in humans with exposure to infected cattle, poultry, and wild birds. No human-to-human transmission has yet been documented. However, for diagnostic preparedness, we evaluated the ability of currently available influenza tests to detect 2024 U.S. H5N1 genotypes, B3.13 and D1.1, predominant in wild birds and poultry. Contrived nasal swab samples were prepared using live or inactivated virus and used to test 12 rapid antigen tests (lateral flow assays, [LFA]), including 10 commercially available influenza A and two H5-specific LFAs. Five point-of-care (POC) molecular assays were also tested. An inclusivity testing protocol utilizing a predetermined dilution series was used to evaluate each assay, enabling a head-to-head comparison of performances. All LFAs and POC molecular tests were able to detect bovine 2024 H5N1 genotype B3.13. Sensitivity for the POC molecular tests (heat-inactivated B3.13) ranged from 1.55 to 7.75 TCID<sub>50</sub>/swab. For 11/12 LFAs, 10 commercial influenza A, and an RUO H5 assay, the sensitivity (live B3.13) ranged from 78 to 1550 TCID<sub>50</sub>/swab. The 12th LFA detected 77,500 TCID<sub>50</sub>/mL transport media. Testing of four LFAs confirmed inclusivity for genotype D1.1. Available influenza tests can detect 2024 U.S. H5N1 strains in contrived samples with a wide range of analytical sensitivity. In the event of human-to-human transmission, clinical performance and optimal sample types would need to be established.IMPORTANCETo date, at least 70 human cases of highly pathogenic avian influenza A (HPAI) H5N1 have been reported. Human-to-human transmission has not yet been reported, but there is ongoing HPAI H5N1 spread within animal and bird populations. As part of pandemic preparedness, it is critical to know whether available tests capable of detecting seasonal influenza A can also detect HPAI H5N1. Our paper describes results from the first study to assess and compare the ability of 10 commercially available influenza A lateral flow assays (LFAs), two LFAs specific for H5 influenza, and five POC molecular tests from three manufacturers to detect the H5N1 virus circulating in U.S. cattle (genotype B3.13). We found that all tests detect HPAI H5N1 in contrived nasal swab specimens, with varying degrees of analytical sensitivity. We also tested a subset of LFAs (three 510k-cleared COVID/flu multiplex tests and an RUO H5-specific LFA) to confirm that they were able to detect a D1.1 genotype (the predominant genotype in wild birds and poultry) strain isolated from a human case of H5N1 in Washington State. Given the persistent circulation of HPAI H5N1 cases, it is critical to know that available tests can analytically detect H5N1. Clinical performance and optimal ","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0054825"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421893/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873440","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":"Detection, quantitation, and genotyping of human papillomavirus circulating tumor DNA by droplet digital PCR.","authors":"Emily C Fernholz, David M Routman, Kathryn M Van Abel, Eric J Moore, Daniel J Ma, Danielle E Hunter, Kathleen R Bartemes, James S Lewis, Erik B Wendlandt, Matthew J Binnicker","doi":"10.1128/jcm.00585-25","DOIUrl":"10.1128/jcm.00585-25","url":null,"abstract":"<p><p>Human papillomavirus (HPV) is comprised of >200 genotypes and has an ~8 kb, circular, double-stranded DNA genome. Transmission of HPV occurs through skin-to-skin contact and infection of squamous epithelial cells of cutaneous and mucosal surfaces. HPV genotypes are categorized as low- or high-risk (hrHPV) based on oncogenic potential. There are approximately 14 types of hrHPV that can cause several types of cancer, including HPV-associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC). Detection of HPV(+)OPSCC is traditionally accomplished using p16 immunohistochemistry (IHC) and HPV-specific testing, either DNA or RNA <i>in situ</i> hybridization (ISH) staining or DNA-based PCR of suspected tumor biopsy tissue. More recently, platelet-poor plasma (PPP) samples from patients with HPV(+)OPSCC have proven useful for detection and quantitation of fragments of HPV circulating tumor DNA (ctDNA). ctDNA has been shown to be useful in determining treatment response and monitoring for disease recurrence. In this study, a novel droplet digital PCR assay (ddPCR) was developed and validated for the detection and quantitation of ctDNA from 5 hrHPV genotypes in PPP. Analytical sensitivity ranged from 7.71 to 19.45 fragments of HPV ctDNA per milliliter of PPP across five hrHPV genotypes. In patients with confirmed primary or recurrent HPV(+)OPSCC or HPV(-)OPSCC, testing of corresponding PPP samples (<i>n</i> = 32) by ddPCR demonstrated 90.63% (29/32) overall agreement with p16/HPV-ISH biopsy results. Compared with reference ddPCR assays performed at outside laboratories, our ddPCR assay yielded 90% (9/10) overall agreement. This assay may provide clinicians with a tool for monitoring HPV ctDNA prior to, during, and after treatment of an HPV-associated cancer.</p><p><strong>Importance: </strong>At least 14 genotypes of human papillomavirus (HPV) have been identified to have high oncogenic potential. While molecular diagnostic testing for HPV is widely available for liquid cytologic cervical samples, testing is limited for other sample types, including liquid biopsy samples, such as platelet-poor plasma (PPP). With the rising incidence of HPV-associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC), laboratory testing is an essential part of patient diagnosis, management, and surveillance. Here, we summarize the development and analytical performance validation of a multiplexed, droplet digital PCR (ddPCR) assay for the detection and quantitation of HPV circulating tumor DNA (ctDNA) in PPP. This assay may provide clinicians with a tool to address minimal residual disease for patients with an HPV-associated cancer.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0058525"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421868/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873437","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":"The impact of commercially available media on cefiderocol susceptibility testing by broth microdilution method.","authors":"Boudewijn L M DeJonge, Christine Slover, Sean T Nguyen, Christopher Longshaw, Miki Takemura, Naomi Anan, Hidenori Yamashiro, Yoshinori Yamano","doi":"10.1128/jcm.00471-25","DOIUrl":"10.1128/jcm.00471-25","url":null,"abstract":"<p><p>The reference method for determining cefiderocol MIC is broth microdilution (BMD) using iron-depleted cation-adjusted Mueller-Hinton broth (ID-CAMHB). However, laboratories have reported variable MIC findings and difficulties in determining MIC endpoints. To investigate this, the BMD method was re-evaluated by examining the chelation time for iron depletion of the media and by testing reproducibility using four MHB sources (BD-BBL, BD-Difco, Oxoid, and Merck) and 85 Gram-negative isolates (<i>Escherichia coli</i>, <i>Klebsiella pneumoniae</i>, <i>Pseudomonas aeruginosa</i>, and <i>Acinetobacter baumannii</i>), of which 63 were previously evaluated <i>in vivo</i>. Extending chelation time to 6 h provided optimal iron reduction to ≤0.03 µg/mL for all media. MIC reproducibility was high for each medium source and varied by species (93.3%-99.0% of MIC values within one dilution of modal MIC values); however, different sources of ID-CAMHB produced (reproducible) different modal MIC values for isolates. ID-CAMHB from BD-BBL and BD-Difco showed the best correlation with 96.5% of isolates showing modal MIC values within one dilution between media. MIC values generated with these two media were the most predictive of efficacy <i>in vivo</i>. When trailing was observed, it was seen across all media, and refined reading guidelines were applied to enhance reproducibility of determining the MIC endpoint. The 6-h chelation and the refined reading guidelines for trailing are now incorporated into the Clinical and Laboratory Standards Institute M100 document. When using the BMD method to determine cefiderocol susceptibility, the impact of media should be considered, and based on these results, ID-CAMHB prepared with BD-BBL or BD-Difco is recommended.IMPORTANCEThe reference antibiotic susceptibility testing method for cefiderocol is the broth microdilution method approved by the Clinical and Laboratory Standards Institute in 2016, using iron-depleted cation-adjusted Mueller-Hinton broth. A few manual devices have come to the market replicating this method, but inconsistent results with these devices have been reported. The current study identified the source of Mueller-Hinton broth as a variable in cefiderocol MIC determinations and provides detailed description of the preparation of iron-depleted cation-adjusted Mueller-Hinton broth, and revised reading guidance to improve reproducibility of cefiderocol MIC determinations for <i>Escherichia coli</i>, <i>Klebsiella pneumoniae</i>, <i>Pseudomonas aeruginosa</i>, and <i>Acinetobacter baumannii</i>. The recommendations made in this study should enhance the reproducibility of cefiderocol broth microdilution susceptibility testing.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0047125"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421808/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956126","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":"Clinical development and performance of the First to Know Syphilis Self-Test for over-the-counter usage: a <i>de novo</i> rapid test for treponemal antibody.","authors":"Kevin Clark, Antony George Joyee, Diane Biddison, Sharon Rabine, Jianghong Qian, Sydney Spradlin, Vicki Thompson, Qinwei Shi, Jing Xu, Lu Zhang, Alicia Brown, Lisa Nibauer, Raji Pillai, Jody D Berry","doi":"10.1128/jcm.00244-25","DOIUrl":"10.1128/jcm.00244-25","url":null,"abstract":"<p><p>The resurgence of syphilis in the USA and globally has hastened the need for widely available syphilis testing. Early detection of syphilis is crucial for avoiding serious clinical complications and preventing the spread of infection. Self-tests enhance access to testing and promote timely treatment for positive cases. Herein, we describe the performance of First to Know Syphilis Test (FTK), the first over-the-counter (OTC) treponemal test. A prospective multi-site clinical study with 1,270 subjects was conducted, where subjects self-collected fingerstick capillary blood and self-tested without assistance. FTK test results were compared with a composite reference standard to evaluate the diagnostic performance. The FTK test exhibited an overall sensitivity of 93.4% (95% CI, 87.0% to 96.8%) and specificity of 99.5% (95% CI, 98.9% to 99.8%) and accuracy of 99%. The overall agreement was 98.9%, with Cohen's Kappa (ⱪ) value 0.93 (95% CI, 0.90 to 0.97) showing excellent agreement between the reference standard and FTK results. In addition, the test was validated in a panel of 125 clinically staged syphilis patient samples, and the results showed 100% agreement in detecting anti-treponemal antibodies in all the samples. These data show excellent performance of the FTK Test, demonstrating its utility in the screening and diagnosis of syphilis. The availability of this OTC test and its excellent performance will have a profound impact on syphilis detection and prevention strategies and could reduce comorbidities such as HIV and transmission of other STIs.</p><p><strong>Importance: </strong>The resurgence of syphilis in the USA and globally underscores the urgent need for rapid, accessible testing. The First To Know Syphilis Test, as the first at-home, over-the-counter (OTC) test for syphilis, represents a significant breakthrough in rapid diagnostics for increased access to testing and support early diagnosis and treatment. The FTK test demonstrated excellent overall clinical performance, with 93.4% sensitivity and 99.5% specificity, confirming its reliability for syphilis detection. This novel, easy-to-use OTC syphilis test allows individuals to privately test at home and can promote testing among those hesitant or unable to seek traditional healthcare, reducing barriers like stigma and limited access. The availability of this OTC test will have a significant impact on syphilis detection and prevention strategies and reduction of comorbidities such as HIV.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0024425"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421861/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144784395","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 fully automated chemiluminescent enzyme immunoassays for hepatitis B core-related antigen components, phosphorylated and non-phosphorylated hepatitis B core antigens: clinical significance and dynamics during hepatitis B e antigen seroconversion.","authors":"Takanori Suzuki, Chiharu Ohue, Osamu Arai, Yuka Inose, Katsuya Nagaoka, Shintaro Ogawa, Takako Inoue, Kentaro Matsuura, Katsumi Aoyagi, Shintaro Yagi, Yasuhito Tanaka","doi":"10.1128/jcm.00385-25","DOIUrl":"10.1128/jcm.00385-25","url":null,"abstract":"<p><p>To assess the performance and clinical relevance of three assays-hepatitis B core-related antigen (HBcrAg), hepatitis B core antigen (HBcAg), and phosphorylated HBcAg (pHBcAg)-in quantifying HBcrAg, a critical biomarker of hepatitis B virus (HBV) infection, fully automated chemiluminescent enzyme immunoassays (CLEIA) for two HBcAg variants were developed. Cutoff values for HBcAg and pHBcAg assays were established at 2.50 and 2.10 LogU/mL, respectively. The strong correlations among components (<i>r</i> = 0.896-0.970) were observed by using purchased 100 plasma samples. When the dynamics of HBcrAg components were analyzed by using a series of hepatitis B e antigen (HBeAg) seroconversion panel, alongside correlations with HBV markers, distinct dynamics and molecular profiles were observed. For the assessment of the clinical relevance of these assays, serum samples were obtained from 102 HBV-infected patients treated with nucleos(t)ide analog (NA). Both HBcAg and pHBcAg levels were significantly reduced during NA therapy, but in different patterns, suggesting HBV activity independent of HBV DNA and persistent HBcrAg components derived from pc-mRNA. OptiPrep density gradient ultracentrifugation analysis identified pHBcAg as the dominant component in high-density fractions. Immunoprecipitation and Western blotting confirmed that HBcAg components were predominantly enveloped by hepatitis B surface antigen (HBsAg), with pHBcAg identified as the major component of empty viral particles. Although the limitation in sample size in this study, the revealed distinct dynamics of HBcAg, pHBcAg, and HBcrAg during seroconversion and treatment suggest these assays could serve as independent biomarkers for monitoring intrahepatic HBV activity and treatment efficacy.IMPORTANCEThis study evaluates novel fully automated chemiluminescent enzyme immunoassay (CLEIA) systems for hepatitis B core antigen (HBcAg) and phosphorylated HBcAg (pHBcAg) and identifies pHBcAg as the predominant component of hepatitis B virus (HBV)-derived empty viral particles, challenging previous assumptions and providing new insights into HBV biomarkers. HBcAg and pHBcAg show distinct dynamics in hepatitis B e seroconversion and nucleos(t)ide treatment from the other biomarkers including hepatitis B core-related antigen (HBcrAg), HBV RNA, and HBV DNA. The developed CLEIA systems for HBcAg and pHBcAg show promise as tools for monitoring intrahepatic HBV activity, immune clearance, and noninfectious viral replication. Incorporating these biomarkers into clinical practice could refine HBV management strategies, improve reactivation risk prediction, and advance precision medicine approaches.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0038525"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421862/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873439","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":"Correction for Brown-Elliott et al., \"Utility of Sequencing the <i>erm</i>(41) Gene in Isolates of <i>Mycobacterium abscessus</i> subsp. <i>abscessus</i> with Low and Intermediate Clarithromycin MICs\".","authors":"Barbara A Brown-Elliott, Sruthi Vasireddy, Ravikiran Vasireddy, Elena Iakhiaeva, Susan T Howard, Kevin Nash, Nicholas Parodi, Anita Strong, Martha Gee, Terry Smith, Richard J Wallace","doi":"10.1128/jcm.00887-25","DOIUrl":"10.1128/jcm.00887-25","url":null,"abstract":"","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0088725"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421867/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956114","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":"A novel single-tier serologic test to diagnose all stages of Lyme disease.","authors":"Andrew E Levin, Gary P Wormser, Elizabeth J Horn, Nadezhda Karaseva, Drew Miller, Hunter Kellogg","doi":"10.1128/jcm.00483-25","DOIUrl":"10.1128/jcm.00483-25","url":null,"abstract":"<p><p>Lyme disease, a bacterial zoonosis, is the most commonly reported vector-borne disease in the United States. Laboratory diagnosis has relied on a two-tier serologic approach, originally comprising an ELISA, or another first-tier assay, followed by separate IgG and IgM immunoblots to confirm a positive first-tier result. This standard two-tier testing (STTT) approach provides high specificity, but at the cost of low sensitivity in early Lyme disease. Recent studies have shown that a modified two-tier (MTTT) testing approach, in which a second ELISA replaces the immunoblot, can provide an increase in test sensitivity without a loss of specificity. Nevertheless, neither STTT nor MTTT is considered sensitive enough for diagnosing patients with erythema migrans, the most common clinical manifestation of early Lyme disease. We have developed a novel ELISA methodology termed \"Hybrid Lyme ELISA\" for single-tier Lyme antibody detection, which relies on the simultaneous binding of individual antibody molecules to the <i>Borrelia burgdorferi</i> surface protein VlsE and to the C6 peptide derived from it. This dual binding requirement builds exceptionally high specificity into the assay, eliminating the majority of non-specific antibody interactions. In this study, the single-tier Hybrid Lyme ELISA was shown to provide greater sensitivity, but with equivalent specificity, to both STTT and MTTT. In addition, given the >90% sensitivity of the Hybrid Lyme ELISA in patients with erythema migrans, this assay may not only transform serologic testing from two-step to single-step testing, but may also provide a means for the first time to diagnose patients with erythema migrans.IMPORTANCEThe diagnosis of Lyme disease, a tick-borne spirochetal infection caused by <i>Borrelia burgdorferi</i> sensu lato, is subject to two major limitations: the need for a two-tier serologic testing algorithm to provide adequate specificity, and the low sensitivity of this algorithm in practice for detection of early Lyme disease manifesting with the erythema migrans skin lesion, the most common clinical manifestation. This study presents the first description of a new assay, the Hybrid Lyme ELISA, which demonstrates sensitivity high enough to potentially diagnose over 90% of patients with erythema migrans, and specificity high enough to preclude the need for a second-tier test. These test characteristics suggest the potential for the Hybrid Lyme ELISA to be the first single-tier serologic test suitable for laboratory diagnosis of all stages of Lyme disease.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0048325"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421848/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144955951","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":"Establishing the reference broth microdilution MIC method for cefepime-taniborbactam.","authors":"Adam Belley, Susan M Cusick, Dan C Pevear, Laura Koeth, Jeanna DiFranco-Fisher, Nimmi Kothari, Stephen Hawser, Greg Moeck","doi":"10.1128/jcm.00661-25","DOIUrl":"10.1128/jcm.00661-25","url":null,"abstract":"<p><p>The investigational β-lactam/β-lactamase inhibitor combination cefepime-taniborbactam is intended as therapy for serious infections caused by Gram-negative pathogens resistant to third-generation cephalosporins and carbapenems. Establishing a susceptibility testing reference method for cefepime-taniborbactam that conforms to the Clinical Laboratory Standards Institute (CLSI) M07 and International Standards Organization 20776-1:2019 standards is necessary to inform patient care. This study describes the reference broth microdilution MIC method for cefepime-taniborbactam (taniborbactam fixed at 4 µg/mL). In a CLSI M23 Tier 2 study that included nine clinical microbiology laboratories, the CTX-M-15-producer <i>Escherichia coli</i> NCTCC 13353 was determined to be appropriate for routine quality control (QC) as ranges for cefepime (≥64 µg/mL) and cefepime-taniborbactam (0.12 to 1 µg/mL) were non-overlapping, thereby simultaneously controlling for cefepime antibacterial activity and taniborbactam β-lactamase inhibition. Of the cefepime-taniborbactam MIC results obtained, 99.6% (269/270) were within the identified QC range; similarly, 100% (79/79) and 98.0% (98/100) of the QC values from a surveillance study and from the two central microbiology laboratories of the CERTAIN-1 Phase 3 clinical study (clintrials.gov identifier NCT03840148) were in range, respectively. Modifications to the standard medium (pH, cation content, or supplementation with human serum, albumin, polysorbate-80, or pulmonary surfactant) or assay parameters (inoculum density, incubation duration, and atmosphere) revealed that only inoculum titers (e.g., ≥5 × 10⁶ CFU/mL) exceeding the CLSI M07 standard (2-8 × 10⁵ CFU/mL) increased MIC values above the QC range. These results demonstrate the robustness and reliability of the cefepime-taniborbactam broth microdilution MIC reference method when performed following the approved standards.</p><p><strong>Importance: </strong>This study focuses on a new antibiotic combination called cefepime-taniborbactam that is being developed to treat serious infections caused by bacteria that are often resistant to current treatments. To make sure this new antibiotic combination can be used safely and effectively once it has been approved for clinical use, we developed a standardized laboratory method to measure its activity against certain bacteria that are widely used during quality control testing. The method was assessed in multiple labs and proved to be reliable, accurate, and consistent. It also held up well under different testing conditions, showing that it is a dependable tool for guiding treatment decisions. This is an important step in meeting the challenge of antibiotic-resistant infections since it will help clinicians evaluate cefepime-taniborbactam as a potential treatment option as they strive to improve the care of patients suffering from serious infections.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0066125"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421830/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873438","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":"Will we miss specific IgA detection for the diagnosis of congenital toxoplasmosis? A French retrospective monocenter study on 483 infants.","authors":"Lya Hamet, Hélène Guegan, Sorya Belaz, Jean-Pierre Gangneux, Florence Robert-Gangneux","doi":"10.1128/jcm.00379-25","DOIUrl":"10.1128/jcm.00379-25","url":null,"abstract":"<p><p>To estimate the performance of anti-<i>Toxoplasma</i> IgA assay for the diagnosis of congenital toxoplasmosis, a retrospective monocenter study was conducted comparing serological results obtained in the framework of routine diagnosis workup. All infants born to mothers infected with <i>Toxoplasma gondii</i> during pregnancy from 2010 to 2023 with at least 6 months of serological follow-up were included. Four hundred and eighty-three cases (1,171 sera) were included, of which 56 infants (11.6%) were infected. Twenty out of 60 infants (33.3%) with positive IgA were not infected. The sensitivity to detect IgA antibodies in infected neonates was 71.4%. The specificity was 97.3%. The mean time to detect IgA was 7.7 ± 13.0 days in infected neonates. Anti-<i>Toxoplasma</i> IgA was the earliest positive serological test in only two cases (5.0%) but turned negative at 1 month in the absence of specific treatment, suggesting non-specific detection. IgA was associated with anti-<i>Toxoplasma</i> IgM, neosynthetized IgG or IgM on comparative Western blotting (WB), or both IgM and neosynthetized IgG or IgM on WB, in 12 cases (30.0%), 2 cases (5.0%), and 19 cases (47.5%), respectively. Sixteen infants with no IgA after birth were diagnosed via neosynthetized IgG or IgM on comparative WB and/or IgM (<i>n</i> = 10), or via PCR on amniotic fluid (<i>n</i> = 5), or persistent IgG (<i>n</i> = 1). Our study suggests that anti-<i>Toxoplasma</i> IgA is not a critical serological parameter for the diagnosis of congenital toxoplasmosis, and the recent withdrawal of commercialized reference anti-<i>Toxoplasma</i> IgA assays should not affect patient care.IMPORTANCEThis study will help clinical microbiologists estimate the impact of the withdrawal of anti-<i>Toxoplasma</i> IgA reference assays for the diagnosis of congenital toxoplasmosis and will contribute to actualize the recommendations for laboratory diagnosis.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0037925"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421870/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144816829","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":"Overview of changes in the Clinical and Laboratory Standards Institute Performance Standards for Antimicrobial Susceptibility Testing: M100 32nd and 33rd editions.","authors":"Audrey N Schuetz, Andrea Ferrell, Janet A Hindler, Romney Humphries, April M Bobenchik","doi":"10.1128/jcm.01623-23","DOIUrl":"10.1128/jcm.01623-23","url":null,"abstract":"<p><p>The Clinical and Laboratory Standards Institute Subcommittee on Antimicrobial Susceptibility Testing (AST) publishes annual updates to the M100 <i>Performance Standards for Antimicrobial Susceptibility Testing</i>. This important document contains key information critical to the laboratory's performance of accurate and current AST. This minireview will highlight and provide supporting data for major changes in the M100 32nd and 33rd editions published in February 2022 and March 2023, respectively. New and revised breakpoints for gram-negative and gram-positive organisms are explained. Proper use of the restructured M100 Table 1 guidance for antimicrobial agents to be considered for testing and reporting is outlined. Reporting guidance for multidrug-resistant gram-negative bacilli is discussed. Other topics within this minireview include additional agents to test and report for direct blood disk diffusion of gram-negative bacilli and quality control range changes and troubleshooting. The minireview concludes with other issues under consideration by the AST Subcommittee.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0162323"},"PeriodicalIF":5.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12421849/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144794553","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}