Browsing by Author "Faron, Matthew L."

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    Cepheid Xpert Xpress Flu/RSV evaluation performed by minimally trained non-laboratory operators in a CLIA-waived environment
    (Elsevier, 2022) Shihabuddin, Bashar S.; Faron, Matthew L.; Relich, Ryan F.; Van Heukelom, Paul; Mayne, Donna; Staat, Mary Allen; Selvarangan, Rangaraj; Hueschen, Leslie A.; Wolk, Donna M.; House, Stacey; Harnett, Glenn; McGann, Kevin; Steele, Mark T.; Romero, Jose R.; Arms, Joe; Lander, Owen; Loeffelholz, Michael; Strouts, Fiona; Cohen, Daniel; Pathology and Laboratory Medicine, School of Medicine
    The COVID-19 pandemic highlighted the significance of readily available and easily performed viral testing for surveillance during future infectious pandemics. The objectives of this study were: to assess the performance of the Xpert Xpress Flu and/or RSV test, a multiplex PCR assay for detecting influenza A and B virus and respiratory syncytial virus nucleic acids in respiratory tract specimens, relative to the Quidel Lyra Influenza A+B assay and the Prodesse ProFlu+ assay, and the system's ease of use by minimally trained operators. Overall, the Xpert Xpress Flu/RSV test demonstrated a high positive and negative percent agreement with the comparator assays, and was easy to use and interpret results, based on the operators' feedback. We concluded that the Xpert Xpress Flu/RSV test is sensitive, specific, and easy to use for the diagnosis of influenza and RSV by minimally trained operators and can be a valuable tool in future infectious clusters or pandemics.
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    Multicenter Clinical Evaluation of the Xpert GBS LB Assay for Detection of Group B Streptococcus in Prenatal Screening Specimens
    (American Society for Microbiology, 2015-02) Buchan, Blake W.; Faron, Matthew L.; Fuller, DeAnna; Davis, Thomas E.; Mayne, Donna; Ledeboer, Nathan A.; Department of Microbiology and Immunology, IU School of Medicine
    Neonatal infection with Streptococcus agalactiae (group B Streptococcus [GBS]) is a leading cause of sepsis and meningitis in newborns. Recent guidelines have recommended universal screening of all pregnant women to identify those colonized with GBS and administration of peripartum prophylaxis to those identified as carriers to reduce the risk of early-onset GBS disease in neonates. Enriched culture methods are the current standard for prenatal GBS screening; however, the implementation of more sensitive molecular diagnostic tests may be able to further reduce the risk of early-onset GBS infection. We report a clinical evaluation of the Xpert GBS LB assay, a molecular diagnostic test for the identification of GBS from broth-enriched vaginal/rectal specimens obtained during routine prenatal screening. A total of 826 specimens were collected from women undergoing prenatal screening (35 to 37 weeks' gestation) and tested at one of three clinical centers. Each swab specimen was tested directly prior to enrichment using the Xpert GBS assay. Following 18 to 24 h of broth enrichment, each specimen was tested using the Xpert GBS LB assay and the FDA-cleared Smart GBS assay as a molecular diagnostic comparator. Results obtained using all three molecular tests were compared to those for broth-enriched culture as the gold standard. The sensitivity and specificity of the Xpert GBS LB assay were 99.0% and 92.4%, respectively, compared to those for the gold standard culture. The Smart GBS molecular test demonstrated sensitivity and specificity of 96.8% and 95.5%, respectively. The sensitivities of the two broth-enriched molecular methods were superior to those for direct testing of specimens using the Xpert GBS assay, which demonstrated sensitivity and specificity of 85.7% and 96.2%, respectively.
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    Multicenter Evaluation of the Portrait Staph ID/R Blood Culture Panel for Rapid Identification of Staphylococci and Detection of the mecA Gene
    (American Society for Microbiology, 2017-04) Denys, Gerald A.; Collazo-Velez, Vanessa; Young, Stephen; Daly, Judy A.; Couturier, Marc Roger; Faron, Matthew L.; Buchan, Blake W.; Ledeboer, Nathan; Pathology and Laboratory Medicine, School of Medicine
    Bloodstream infections are a leading cause of morbidity and mortality in the United States and are associated with increased health care costs. We evaluated the Portrait Staph ID/R blood culture panel (BCP) multiplex PCR assay (Great Basin Scientific, Salt Lake City, UT) for the rapid and simultaneous identification (ID) of Staphylococcus aureus, Staphylococcus lugdunensis, and Staphylococcus species to the genus level and the detection of the mecA gene directly from a positive blood culture bottle. A total of 765 Bactec bottles demonstrating Gram-positive cocci in singles or clusters were tested during the prospective trial at 3 clinical sites. The Portrait Staph ID/R BCP results were compared with results from conventional biochemical and cefoxitin disk methods performed at an independent laboratory. Discordant ID and mecA results were resolved by rpoB gene sequencing and mecA gene sequencing, respectively. A total of 658 Staphylococcus species isolates (S. aureus, 211 isolates; S. lugdunensis, 3 isolates; and Staphylococcus spp., 444 isolates) were recovered from monomicrobial and 33 polymicrobial blood cultures. After discrepant analysis, the overall ratios of Portrait Staph ID/R BCP positive percent agreement and negative percent agreement were 99.4%/99.9% for Staphylococcus ID and 99.7%/99.2% for mecA detection.