Wendy A Szymczak, Anne Line Engsbro, Jan Gorm Lisby, Juan José González-López, Paul Granato, Nathan Ledeboer, Donna M Wolk, Stephen Young, Daniel D Rhoads, Yvan Caspar, Lisa Steed, Romney Humphries, Christopher Bielefeldt, Markus Hermanowski, Juana L de Diego, Hendrik Leibhan, Pau Boher, Carla Camprubí, Maria Orthodoxou, Ester Sala, Sarah Johnson, Martí Juanola-Falgarona, Davide Manissero, Johanna Bialas
{"title":"Multicenter evaluation of the QIAstat-Dx Gastrointestinal Panel 2, a multiplex PCR platform for the diagnosis of acute gastroenteritis.","authors":"Wendy A Szymczak, Anne Line Engsbro, Jan Gorm Lisby, Juan José González-López, Paul Granato, Nathan Ledeboer, Donna M Wolk, Stephen Young, Daniel D Rhoads, Yvan Caspar, Lisa Steed, Romney Humphries, Christopher Bielefeldt, Markus Hermanowski, Juana L de Diego, Hendrik Leibhan, Pau Boher, Carla Camprubí, Maria Orthodoxou, Ester Sala, Sarah Johnson, Martí Juanola-Falgarona, Davide Manissero, Johanna Bialas","doi":"10.1128/jcm.01983-24","DOIUrl":"10.1128/jcm.01983-24","url":null,"abstract":"<p><p>The QIAstat-Dx Gastrointestinal Panel 2 (GI2 Panel) is a sample-to-answer multiplex PCR instrument that can detect 17 targets in a run time of about 80 minutes. The performance of the QIAstat-Dx GI2 Panel was evaluated by testing 1,939 prospective, 119 prospectively collected and then archived positive clinical samples and 750 retrospective clinical specimens across 13 sites in Europe and the United States. Specimens tested included bulk stool samples preserved in modified Cary-Blair transport medium. For most targets, results were compared to those of the FilmArray GI panel (13/17), and discordant results were adjudicated with a third assay. For the remaining targets (4/17), a composite comparator method was used, which included three comparator assays for each target. Before discordant resolution, the QIAstat-Dx GI2 Panel positive percent agreement (PPA) was 95% or greater for 5/17 targets (<i>Campylobacter</i>, <i>E. coli</i> O157, <i>Cryptosporidium, Cyclospora cayetanensis,</i> and <i>Giardia lamblia</i>) and 90% or greater for 11/17 targets: adenovirus F40/F41, astrovirus, norovirus GI/GII, rotavirus A, <i>Plesiomonas shigelloides</i>, enteropathogenic <i>Escherichia coli</i>, enterotoxigenic <i>E. coli</i>, <i>Salmonella</i>, <i>Yersinia enterocolitica,</i> Shiga-like toxin <i>E. coli</i> (STEC) <i>stx1/stx2</i>, and <i>Shigella</i>/enteroinvasive <i>E. coli</i>. No cases of <i>Entamoeba histolytica</i> were encountered during the clinical study. The negative percent agreement (NPA) was >98.9% for all QIAstat-Dx GI2 Panel targets. The three most common pathogens identified in single and co-infections were enteropathogenic <i>E. coli</i> (9.9%), <i>Campylobacter</i> (5.2%), and norovirus GI/GII (3.1%). In summary, this clinical study examined more than 2,800 samples from Europe and the U.S. using the QIAstat-Dx GI2 Panel and identified 90%-100% PPA and 99% NPA for its 17 targets.IMPORTANCEThe manuscript highlights the significance and impact of the QIAstat-Dx GI2 Panel, a sample-to-answer multiplex PCR instrument capable of detecting 17 targets in approximately 80 minutes. This comprehensive clinical study, conducted across 13 sites in Europe and the United States, evaluated the performance of the panel using over 2,800 clinical samples. The results demonstrate a high accuracy of the QIAstat-Dx GI2 panel, with a PPA equal to or higher than 90% for all targets and an NPA greater than 98.9% for all targets. These findings underscore the reliability and effectiveness of the GI2 panel in the rapid and precise detection of gastrointestinal pathogens, which is crucial for timely diagnosis and treatment of infections.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0198324"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345276/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144608539","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}
Nisha Nair, Adriana Marques, Elizabeth J Horn, Grant Brown, Maria Gomes-Solecki
{"title":"Class and isotype of VlsE-specific antibody differentiates Lyme disease stage.","authors":"Nisha Nair, Adriana Marques, Elizabeth J Horn, Grant Brown, Maria Gomes-Solecki","doi":"10.1128/jcm.00347-25","DOIUrl":"10.1128/jcm.00347-25","url":null,"abstract":"<p><p>Establishment of immunoglobulin diversity is contingent on recombination that occurs both at the Fab and at the Fc regions of the immunoglobulin, and this process is time dependent. Based on this principle, we questioned whether Lyme disease stage can be distinguished by quantification of immunoglobulin class and IgG isotype specific to VlsE in serum from clinically characterized patients. We used an enzyme immunoassay to categorize serologic antibodies to VlsE antigen as well as machine-learning techniques to train and integrate multiple predictors to identify likely disease stage. We found that IgM/IgG3/IgG1/IgA1 was enriched in serum obtained in the earliest stages, whereas IgG3/IgG1/IgG4 was enriched in Lyme arthritis. IgG2 detection was unremarkable across all disease stages. Post-Treatment Lyme Disease Syndrome (PTLDS) serum was enriched in IgG3/IgG1/IgA1 but lacked IgM. The multivariable models showed better predictive accuracy than any single immunoglobulin model, with more than half of panels perfectly identified by random forest under cross validation (56%) vs a maximum of 38% for a model using IgG1 alone. The findings suggest a characteristic succession of VlsE-specific antibody switching between immunoglobulin class and IgG isotype as Lyme disease progresses from early to late stages. The data also suggest that immunoglobulin class and IgG isotyping are likely more helpful to distinguish early Lyme disease cases. Comprehensive evaluation of immunoglobulin class (M, G, A) and IgG isotypes (1/2/3/4) provides time-dependent pathogen-induced host response information to current Lyme disease antibody detection and may be useful for differentiation of disease stage.</p><p><strong>Importance: </strong>The order of switching between the immunoglobulin heavy chain (Fc) is time dependent, progressing from IgM/D to IgG3/IgG1/IgA1/IgG2/IgG4 and later to IgE/IgA2. In this study, we show that <i>B. burgdorferi</i>-VlsE-specific antibody switching proceeds in a predictable sequence between class (Ig M/G/A) and IgG isotype (IgG 1/2/3/4) as Lyme disease progresses from early to late stage and that antibody class and isotype may be more helpful to distinguish the early stages of Lyme disease. This study advances our understanding of the tempo and structure of the humoral immune response to <i>B. burgdorferi</i> and is applicable to the development of new diagnostic assays for Lyme disease.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0034725"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345165/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637101","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}
Konrad M Wesselmann, Cécile Baronti, Antoine Nougairède, Laurence Thirion, Xavier de Lamballerie, Remi Charrel, Laura Pezzi
{"title":"Development and evaluation of a duplex RT-qPCR assay for the detection and identification of Mayaro and chikungunya viruses.","authors":"Konrad M Wesselmann, Cécile Baronti, Antoine Nougairède, Laurence Thirion, Xavier de Lamballerie, Remi Charrel, Laura Pezzi","doi":"10.1128/jcm.00420-25","DOIUrl":"10.1128/jcm.00420-25","url":null,"abstract":"<p><p>Mayaro virus (MAYV) is a mosquito-borne alphavirus that is widespread in the Amazon basin, where it co-circulates with the closely related chikungunya virus (CHIKV). Due to the limited surveillance and technical limitations of diagnostic assays (scarcity of commercial assays, serology cross-reactivity), the true burden of MAYV is uncertain. We designed a new RT-qPCR assay targeting the nsp1 gene for MAYV detection, which can be used in monoplex or duplex format. In the duplex format, the new MAYV assay is combined with a CHIKV assay and a second MAYV assay, both previously published. The lower limit of detection with a 95% positivity rate was determined to be <10 RNA copies/μL in monoplex and duplex formats for both MAYV and CHIKV. Monoplex and duplex assays proved to be linear within the tested range of approximately 10<sup>8</sup> to 10<sup>2</sup> RNA copies/μL and showed 100% specificity against a wide panel of arboviruses as well as several other pathogens in clinical samples. The testing of CHIKV-positive sera and MAYV-spiked plasma samples confirmed the suitability of the assays in a clinical setting. These assays offer a reliable tool for detection and differentiation of MAYV and CHIKV in endemic settings.IMPORTANCEMolecular diagnostic capabilities for detecting alphaviruses other than chikungunya virus (CHIKV) remain limited. Mayaro virus (MAYV), an emerging mosquito-borne alphavirus, co-circulates with CHIKV in the Americas, making clinical differentiation between the two viruses challenging. To address this, we developed a novel RT-qPCR assay specifically for the detection of MAYV, which can also be used in a duplex format to simultaneously detect and distinguish CHIKV. The assay was thoroughly evaluated in both monoplex and duplex formats and demonstrated high sensitivity and specificity. This new tool is particularly valuable for the detection of MAYV, especially in resource-limited settings, where its duplex format offers efficient and accurate differentiation of acute infections.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0042025"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345196/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144553625","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":"Update on North American tick-borne diseases and how to diagnose them.","authors":"Kyle G Rodino, Elitza S Theel, Bobbi S Pritt","doi":"10.1128/jcm.00807-23","DOIUrl":"10.1128/jcm.00807-23","url":null,"abstract":"<p><p>Recent decades have seen a rise in the incidence of tick-borne diseases in the US, along with an increased number of pathogens transmitted by ticks, and geographic expansion of tick populations. A variety of laboratory testing methodologies are available for the diagnosis of tick-borne diseases, including serology, microscopy, and molecular-based methods. The preferred approach varies by the specific disease, locally available test options, and the stage of illness at patient presentation. This mini-review focuses on updates in our understanding of the epidemiology of tick-borne diseases in the US and advances in the field of laboratory diagnostics.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0080723"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345162/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144608541","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}
Yuan Chao Xue, Jennifer Bertsch, Kaylin Monacy, Carter Haynes, Natalie Williams-Bouyer, Barbara M Judy, Patrick C Newman, Thomas G Ksiazek, Lyudmyla V Marushchak, Gregory C Gray, Ping Ren
{"title":"Enhancing diagnostic preparedness for H5N1: a validation study of H5 single-plex assay and detection across multiple platforms.","authors":"Yuan Chao Xue, Jennifer Bertsch, Kaylin Monacy, Carter Haynes, Natalie Williams-Bouyer, Barbara M Judy, Patrick C Newman, Thomas G Ksiazek, Lyudmyla V Marushchak, Gregory C Gray, Ping Ren","doi":"10.1128/jcm.00681-25","DOIUrl":"10.1128/jcm.00681-25","url":null,"abstract":"<p><p>The increasing transmission of highly pathogenic avian influenza (HPAI) H5N1 from animals to humans underscores the urgent need for enhanced diagnostic capabilities in clinical microbiology laboratories. Although <i>in silico</i> analysis suggests that commercial multiplex respiratory panels can detect H5N1, these assays lack subtyping H5N1 capabilities, and their real-world performance remains largely unverified. In this study, we evaluated the limit of detection (LoD) for H5N1 using three commercial molecular diagnostic assays routinely employed at our institution: bioMérieux BioFire Respiratory 2.1 Panel, Cepheid Xpert Xpress CoV-2/Flu/RSV Plus, and Hologic Panther Fusion SARS-CoV-2/Flu A/B/RSV assays. All three reliably detected H5N1 were at low viral concentrations. To enable H5N1 detection, we also developed a real-time RT-PCR H5 single-plex assay on the Hologic Panther Fusion Open Access platform for reflex testing of influenza A-positive specimens. In conclusion, although current commercial assays lack influenza A H5 subtype differentiation, our validation data provide critical performance information. When integrated with a targeted H5 assay, these tools can enhance clinical decision-making and public health surveillance by reducing the risk of missed H5N1 infection cases.IMPORTANCEThis study addresses a growing public health concern: the spread of bird flu (H5N1) from animals to humans. Most hospital laboratories use commercial tests to detect respiratory viruses like the flu, but these tests cannot tell if someone has the specific and more dangerous H5N1 strain. To help solve this, we tested three commonly used diagnostic tools and found that they can detect H5N1 even at low levels. However, since they cannot identify the specific H5 subtype, we also developed and validated a follow-up test that runs on one of the existing laboratory high-throughput equipment. This test can confirm whether a patient infected with the flu has the H5N1 strain. By combining these tools, hospital laboratories can improve early detection of H5N1, support better patient care, and help public health officials respond more effectively to outbreaks.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0068125"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345207/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144659366","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}
Jianqiang Zhang, Liying Tian, Jaime Dittman, Baoqing Guo, Kay Kimpston-Burkgren, Erin Kalkwarf, Eman Gadu, Phillip Gauger, Mohamed El-Gazzar, Yuko Sato
{"title":"Isolation and characterization of avian metapneumovirus subtypes A and B associated with the 2024 disease outbreaks among poultry in the USA.","authors":"Jianqiang Zhang, Liying Tian, Jaime Dittman, Baoqing Guo, Kay Kimpston-Burkgren, Erin Kalkwarf, Eman Gadu, Phillip Gauger, Mohamed El-Gazzar, Yuko Sato","doi":"10.1128/jcm.00333-25","DOIUrl":"10.1128/jcm.00333-25","url":null,"abstract":"<p><p>Avian metapneumovirus (aMPV) is currently classified into four subtypes (aMPV-A, -B, -C, and -D). In late 2023 and early 2024, aMPV-A and aMPV-B were detected in US poultry for the first time, causing significant economic losses. This study analyzed aMPV RT-PCR data from 2,204 samples (1,158 turkey, 936 chicken, and 110 other breeds) submitted to a US veterinary diagnostic laboratory between January and November 2024. A higher percentage of turkey samples (51.04%) tested PCR-positive for aMPV-A and/or aMPV-B compared to chicken samples (15.6%), with aMPV-A showing an overall higher positive rate than aMPV-B, although the positive rates varied by state. Additionally, four aMPV-A and three aMPV-B isolates were successfully recovered from clinical samples using primary chicken embryo lung and/or fibroblast cells. Two aMPV-A isolates (USA/IA55601-6/2024 and USA/IA56509-5/2024) and two aMPV-B isolates (USA/NC20487-GA/2024 and USA/NC23734-GA/2024) were adapted to grow efficiently in a Vero cell line, reaching titers of ~10<sup>4</sup>-10<sup>6</sup> TCID<sub>50</sub>/mL between passages 4 and 10 for aMPV-A and between passages 1 and 10 for aMPV-B. Whole genome sequencing of the two aMPV-A and two aMPV-B isolates at different passages revealed that the viruses progressively acquired several nucleotide changes, some of which led to amino acid substitutions in different viral proteins during 10 passages in cell culture. Comparative analysis with 46 aMPV-A, -B, -C, and -D GenBank sequences showed that US aMPV-A and aMPV-B strains were genetically closely related within their subtypes. These cell culture-adapted US aMPV-A and aMPV-B isolates provide valuable tools for further characterization of aMPV and vaccine development.</p><p><strong>Importance: </strong>Avian metapneumovirus (aMPV) subtypes A and B were first detected in US poultry in late 2023 and early 2024, rapidly spreading nationwide and posing a significant threat to the industry. This study analyzed RT-PCR data from 2,204 clinical samples (January to November 2024) to determine aMPV-A and aMPV-B detection rates across poultry species, age groups, and states, providing insights into their epidemiology in the USA. Modified live vaccines are urgently needed to control aMPV but are hindered by the lack of US isolates growing efficiently in cell culture. We successfully isolated aMPV-A and aMPV-B in primary chicken embryo cells and adapted them to a Vero cell line. Their infectious titers and genetic stability were characterized over serial passages. These US aMPV-A and aMPV-B cell culture isolates provide valuable tools for studying pathogenesis, determining virus infectious doses, evaluating disinfectants and antivirals, and developing vaccines.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0033325"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345154/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144600612","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}
Petra Drzewnioková, Irene Brian, Marzia Mancin, Andrea Fortin, Morgane Gourlaouen, Angélique Angot, Mamadou Niang, Isaac Dah, Kouramoudou Berete, Adama Diakite, Fatou Tall Lo, Clement Meseko, Emilie Go-Maro, Valeria D'Amico, Viviana Valastro, Baba Soumare, Paola De Benedictis, Isabella Monne, Valentina Panzarin
{"title":"Validation and multi-site deployment of a lyophilized qRT-PCR reagent for the molecular diagnosis of avian influenza and rabies in Sub-Saharan African regions.","authors":"Petra Drzewnioková, Irene Brian, Marzia Mancin, Andrea Fortin, Morgane Gourlaouen, Angélique Angot, Mamadou Niang, Isaac Dah, Kouramoudou Berete, Adama Diakite, Fatou Tall Lo, Clement Meseko, Emilie Go-Maro, Valeria D'Amico, Viviana Valastro, Baba Soumare, Paola De Benedictis, Isabella Monne, Valentina Panzarin","doi":"10.1128/jcm.00080-25","DOIUrl":"10.1128/jcm.00080-25","url":null,"abstract":"<p><p>Molecular methods are widely accepted as gold-standard techniques for the laboratory diagnosis of most human and animal pathogens. However, most molecular protocols rely on reagents that need to be transported and stored at a freezing temperature, a requirement that might affect their reliability in areas where the cold chain cannot be guaranteed. Over the years, several lyophilized molecular products have been marketed to circumvent this issue. We therefore evaluated the feasibility of replacing liquid reagents with freeze-dried formulations for the molecular diagnosis of avian influenza (AIV) and rabies (RABV) viruses, two priority zoonotic pathogens widely spread in Sub-Saharan Africa. Among six different commercial freeze-dried kits, we selected one reagent due to its easy-to-use features, single-reaction format, and preliminary performance assessment. Through a more in-depth evaluation, we determined its analytical and diagnostic performance and formulation stability and obtained results comparable to those of standard liquid master mixes. However, for the detection of divergent lyssaviruses, the lyophilized reagent's sensitivity was affected by suboptimal complementarity between the oligonucleotides and target sequences. Finally, a multi-site evaluation in four veterinary diagnostic laboratories located in Sub-Saharan Africa demonstrated the successful deployment of AIV and RABV assays utilizing the freeze-dried reagent, which can interchangeably replace liquid qRT-PCR/RT-PCR kits. Altogether, our results indicate that the investigated lyophilized master mix represents a valid alternative to liquid reagents for the molecular diagnosis of avian influenza and rabies and has the potential for broader applications to other relevant infectious diseases upon proper validation.IMPORTANCEMolecular diagnostic protocols rely on reagents that need to be transported and stored at freezing temperatures. Meeting this requirement can be challenging in areas where the maintenance of the cold chain is not guaranteed, such as in Sub-Saharan Africa. Our study aimed to assess the feasibility of using lyophilized reagents as a replacement for liquid reagents in the molecular diagnosis of two widespread zoonotic pathogens in Sub-Saharan Africa, namely, avian influenza and rabies. To accomplish this, we selected a commercially available lyophilized reagent based on its format and performance characteristics. We conducted a laboratory validation to assess the use of the lyophilized reagent throughout the entire diagnostic process. We also conducted a reproducibility test involving African laboratories as potential end-users. Our findings confirm that the lyophilized reagent can replace traditional liquid reagents to diagnose rabies and avian influenza and suggest its possible use for a wider range of infectious diseases after undergoing appropriate validation.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0008025"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345159/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144540377","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}
Lucas J Osborn, Lindsay Osborn, Irvin Ibarra-Flores, Marisol Garcia, Kaitlyn Perez, Ali Farhadiayoubloo, Melissa Mitrou, Cristina Costales, Jennifer Dien Bard
{"title":"Performance evaluation of early growth isolates for automated and manual broth microdilution antimicrobial-susceptibility testing.","authors":"Lucas J Osborn, Lindsay Osborn, Irvin Ibarra-Flores, Marisol Garcia, Kaitlyn Perez, Ali Farhadiayoubloo, Melissa Mitrou, Cristina Costales, Jennifer Dien Bard","doi":"10.1128/jcm.00236-25","DOIUrl":"10.1128/jcm.00236-25","url":null,"abstract":"<p><p>Prolonged turnaround times (TAT) represent a major limitation to current automated susceptibility testing systems and manual susceptibility-testing methods such as broth microdilution. As a result, targeted therapy for patients may be delayed, portending suboptimal clinical outcomes. One contributing factor is the 18-24 h of incubation prior to antimicrobial-susceptibility testing (AST) recommended by the Clinical Laboratory Standards Institute (CLSI) and some automated AST manufacturers. This study evaluates the performance of AST by manual broth microdilution (Thermo Fisher Sensititre) and an automated AST system (BD Phoenix) on isolates incubated for 6 h (early growth AST, egAST) compared with 18-24 h (standard growth AST, sgAST). An initial proof-of-concept study conducted on gram-negative (<i>n</i> = 5) and gram-positive (<i>n</i> = 2) quality control strains incubated for 6 or 24 h prior to Sensititre and Phoenix demonstrated 100% essential agreement. Subsequently, we evaluated the performance of egAST on gram-positive (<i>n</i> = 49, Phoenix; <i>n</i> = 46 Sensititre) and gram-negative (<i>n</i> = 81 Phoenix; <i>n</i> = 61 Sensititre) patient-derived isolates with diverse resistance profiles compared with sgAST. In total, 1,666 organism-drug combinations were tested by Sensititre (560 gram-positive and 1,106 gram-negative) and 1,927 by Phoenix (409 gram-positive and 1,518 gram-negative). For <i>Enterobacterales</i>, egAST using Phoenix revealed 1.3% minor errors (MiE), 0.17% major errors (ME), and 1.1% very major errors (VME) compared with sgAST. Phoenix egAST performance for <i>Pseudomonas aeruginosa</i> revealed 0.18% MiE and no ME or VME. Similarly, egAST of <i>Enterobacterales</i> by Sensititre revealed 1.5% MiE and no ME or VME, whereas 2.8% MiE, 6.6% ME, and no VME were observed for <i>P. aeruginosa</i>. For <i>Staphylococcus</i> spp. and <i>Enterococcus</i> spp., there were no MiE, ME, or VME on the Phoenix system, whereas early growth Sensititre showed 3.14% MiE, 0.3% ME, and 2.99% VME for <i>Staphylococcus</i> spp. and 6.8% MiE, 0.09% ME, and no VME for <i>Enterococcus</i> spp. Taken together, these data suggest that egAST represents a viable strategy to reduce the prolonged incubation period currently recommended by CLSI and select automated AST manufacturer guidelines without incurring any additional costs while simultaneously maintaining high concordance with reference standard methods.IMPORTANCETraditional antimicrobial-susceptibility testing (AST) methods typically span several days from the time of organism isolation. The majority of this time is spent waiting for a cultured isolate to incubate up to 1 day prior to AST. There exists an unmet need to provide more rapid AST as various rapid methods have been shown to reduce exposure to broad-spectrum antibiotics that select for antimicrobial resistance, shorten hospital stays, and improve clinical outcomes. Simultaneously, there is a need to ensure that rapid AST approac","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0023625"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345138/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528222","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}
Annie Sanchez, Michael Rauch, Sherry Buechner, Brittney Jung-Hynes, Eric Beck, Allen Bateman
{"title":"Percentage of culture confirmation and melting curve analysis reveals false-positive <i>Campylobacter</i> detection in a molecular syndromic panel.","authors":"Annie Sanchez, Michael Rauch, Sherry Buechner, Brittney Jung-Hynes, Eric Beck, Allen Bateman","doi":"10.1128/jcm.00028-25","DOIUrl":"10.1128/jcm.00028-25","url":null,"abstract":"<p><p>Surveillance of enteric organisms can identify outbreaks and support control measures. The BIOFIRE FilmArray Gastrointestinal Panel (FilmArray GI) is the most common culture-independent diagnostic test (CIDT) used in Wisconsin to diagnose enteric infections. State clinical laboratories have raised concerns about inaccurate <i>Campylobacter</i> detection with the FilmArray GI. The Wisconsin State Laboratory of Hygiene (WSLH) evaluated the percentage of positivity and culture confirmations stratified by CIDT for <i>Campylobacter</i>, <i>Salmonella</i>, and STEC from 2018 to 2024. We further analyzed the transport time of <i>Campylobacter</i> specimens and the melt curves of specimens that tested positive by FilmArray GI. <i>Campylobacter</i>, <i>Salmonella</i>, and STEC specimens tested on the FilmArray GI had increases in percentage of positivity compared to those tested on other CIDTs. <i>Salmonella</i> and STEC specimens positive by FilmArray GI, compared to other CIDTs, had no significant culture confirmation differences. However, <i>Campylobacter</i> specimens positive by FilmArray GI had significantly lower culture confirmations than positive specimens from other CIDTs (62% vs. 78%; <i>P</i> < 0.05). <i>Campylobacter c</i>ulture confirmations were lower for FilmArray GI specimens, compared to other CIDTs, regardless of how many days the specimen spent in transport in 2023. Additionally, we found atypical melt curves among specimens positive by FilmArray GI with cultures that did not grow <i>Campylobacter</i>. Taken together, the higher percentage of positivity, the lower percentage of culture confirmation, and the atypical melt curves suggest that the FilmArray GI might yield false-positive <i>Campylobacter</i> results. These findings emphasize the importance of public health surveillance to identify potential issues with commercially available diagnostic tests.IMPORTANCEEnteric pathogens cause ~9.4 million illnesses annually in the United States. Clinical laboratories rely on culture-independent diagnostic testing platforms (CIDTs) for rapid and accurate diagnosis of enteric pathogens. <i>Campylobacter</i>, <i>Salmonella</i>, and Shiga-toxin-producing <i>Escherichia coli</i> (STEC) are three of the most identified enteric bacterial infections in Wisconsin. The BioFire FilmArray Gastrointestinal panel (FilmArray GI) is currently the most common CIDT used by Wisconsin clinical laboratories to diagnose <i>Campylobacter</i>, <i>Salmonella</i>, and STEC infections. However, the FilmArray GI has had notable issues and recalls in the past. Here, we used public health surveillance data to assess platform performance for these organisms. We analyzed percent positivity and culture confirmations based on testing platforms. Through our analysis, we identified potential false-positive <i>Campylobacter</i> results from the FilmArray GI, which were associated with atypical melt curve profiles on the BioFire platform. Public health surveillance can he","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0002825"},"PeriodicalIF":5.4,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12345244/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144626430","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}