Publications by authors named "Frederick Nolte"

Unlabelled: Sequencing of plasma microbial cell-free DNA (mcfDNA) has gained increased acceptance as a valuable adjunct to standard-of-care testing for diagnosis of infections throughout the body. Here, we report the analytical and clinical validation of a novel application of mcfDNA sequencing, the non-invasive detection of seven common antimicrobial resistance (AMR) genetic markers in 18 important pathogens. The AMR markers include SCC, , , , and .

View Article and Find Full Text PDF

Introduction: Immunocompromised host pneumonia (ICHP) is an important cause of morbidity and mortality, yet usual care (UC) diagnostic tests often fail to identify an infectious etiology. A US-based, multicenter study (PICKUP) among ICHP patients with hematological malignancies, including hematological cell transplant recipients, showed that plasma microbial cell-free DNA (mcfDNA) sequencing provided significant additive diagnostic value.

Aim: The objective of this study was to perform a cost-effectiveness analysis (CEA) of adding mcfDNA sequencing to UC diagnostic testing for hospitalized ICHP patients.

View Article and Find Full Text PDF

Background: The 2022 global outbreak of Monkeypox virus (MPXV) highlighted challenges with polymerase chain reaction detection as divergent strains emerged and atypical presentations limited the applicability of swab sampling. Recommended testing in the United States requires a swab of lesions, which arise late in infection and may be unrecognized. We present MPXV detections using plasma microbial cell-free DNA (mcfDNA) sequencing.

View Article and Find Full Text PDF

The use of clinical molecular diagnostic methods for detecting microbial pathogens continues to expand and, in some cases, supplant conventional identification methods in various scenarios. Analytical and clinical benefits of multiplex molecular panels for the detection of respiratory pathogens have been demonstrated in various studies. The use of these panels in managing different patient populations has been incorporated into clinical guidance documents.

View Article and Find Full Text PDF

Microbial cell-free DNA (mcfDNA) sequencing is an emerging infectious disease diagnostic tool which enables unbiased pathogen detection and quantification from plasma. The Karius Test, a commercial mcfDNA sequencing assay developed by and available since 2017 from Karius, Inc. (Redwood City, CA), detects and quantifies mcfDNA as molecules/μL in plasma.

View Article and Find Full Text PDF

Clinical Microbiology Open (CMO), a meeting supported by the American Society for Microbiology's Clinical and Public Health Microbiology Committee (CPHMC) and Corporate Council, provides a unique interactive platform for leaders from diagnostic microbiology laboratories, industry, and federal agencies to discuss the current and future state of the clinical microbiology laboratory. The purpose is to leverage the group's diverse views and expertise to address critical challenges, and discuss potential collaborative opportunities for diagnostic microbiology, through the utilization of varied resources. The first and second CMO meetings were held in 2018 and 2019, respectively.

View Article and Find Full Text PDF
Article Synopsis
  • The Abbott Global Surveillance program is monitoring the ability of various diagnostic tests to detect different circulating variants of SARS-CoV-2, including major variants of concern like alpha, beta, gamma, and delta.
  • A study was conducted using live virus cultures and clinical samples, testing numerous Abbott assays for their effectiveness in identifying these variants.
  • Results showed that all molecular assays successfully detected 100% of variant patient specimens, while antigen tests also performed well, confirming the reliability of Abbott's diagnostics against ongoing viral diversity.
View Article and Find Full Text PDF

The U.S. Food & Drug Administration (FDA) regulates the marketing of manufacturers' diagnostic tests (IVDs), including assays for the detection of SARS-CoV-2.

View Article and Find Full Text PDF
Article Synopsis
  • The SARS-CoV-2 pandemic has highlighted the need for deeper research into immune responses for better treatments and vaccines.
  • A study screened over 60,000 asymptomatic people in the Southeastern U.S., finding about 3% had positive IgG antibodies against the viral Spike protein, with higher levels linked to better inhibition of ACE2 binding.
  • Compared to asymptomatic individuals, SARS-CoV-2 symptomatic patients showed lower antibody responses and less effective inhibition of ACE2, suggesting that healthy individuals can generate strong immune responses without showing symptoms.
View Article and Find Full Text PDF

We verified the analytical performance of the Abbott RealTie SARS-CoV-2 assay on the 2000 system and compared its clinical performance to the CDC 2019-nCoV real-time PCR diagnostic panel and the Thermo Fisher TaqPath RT-PCR COVID-19 kit. We also performed a bridging study comparing the RealTie SARS-CoV-2 assay with the new Abbott Alinity SARS-CoV-2 assay. A number of standards, reference materials, and commercially available controls were used for the analytical verification to confirm the limit of detection, linearity, and reproducibility.

View Article and Find Full Text PDF

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody testing is an important tool in assessment of pandemic progress, contact tracing, and identification of recovered coronavirus disease 2019 (COVID-19) patients. We evaluated an orthogonal testing algorithm (OTA) to improve test specificity in these use cases.

Methods: A two-step OTA was applied where individuals who initially tested positive were tested with a second test.

View Article and Find Full Text PDF

Clinical molecular laboratory professionals are at the frontline of the response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, providing accurate, high-quality laboratory results to aid in diagnosis, treatment, and epidemiology. In this role, we have encountered numerous regulatory, reimbursement, supply-chain, logistical, and systems challenges that we have struggled to overcome to fulfill our calling to provide patient care. In this Perspective from the Association for Molecular Pathology Infectious Disease Subdivision Leadership team, we review how our members have risen to these challenges, provide recommendations for managing the current pandemic, and outline the steps we can take as a community to better prepare for future pandemics.

View Article and Find Full Text PDF

Routine identification of fungal pathogens from positive blood cultures by culture-based methods can be time-consuming, delaying treatment with appropriate antifungal agents. The GenMark Dx ePlex investigational use only blood culture identification fungal pathogen panel (BCID-FP) rapidly detects 15 fungal targets simultaneously in blood culture samples positive for fungi by Gram staining. We aimed to determine the performance of the BCID-FP in a multicenter clinical study.

View Article and Find Full Text PDF

Rapid identification from positive blood cultures is standard of care (SOC) in many clinical microbiology laboratories. The GenMark Dx ePlex Blood Culture Identification Gram-Positive (BCID-GP) Panel is a multiplex nucleic acid amplification assay based on competitive DNA hybridization and electrochemical detection using eSensor technology. This multicenter study compared the investigational-use-only (IUO) BCID-GP Panel to other methods of identification of 20 Gram-positive bacteria, four antimicrobial resistance genes, and both Pan and Pan Gram-Negative targets that are unique to the BCID-GP Panel.

View Article and Find Full Text PDF

Background: Procalcitonin (PCT) is a well-established marker for bacterial infection. Recently the US Food and Drug Administration approved the expanded use of this biomarker to guide clinical decisions for antibiotic treatment in patients with lower respiratory tract infections. Both the Architect BRAHMS PCT (PCT-A) and Vidas BRAHMS PCT (PCT-V) are approved for this indication.

View Article and Find Full Text PDF

Background: Health care and public health professionals rely on accurate, real-time monitoring of infectious diseases for outbreak preparedness and response. Early detection of outbreaks is improved by systems that are comprehensive and specific with respect to the pathogen but are rapid in reporting the data. It has proven difficult to implement these requirements on a large scale while maintaining patient privacy.

View Article and Find Full Text PDF

Respiratory pathogens have been detected in forensic investigations using multiple techniques; however, no study has examined the use of automated, nested, multiplex polymerase chain reaction (ANM-PCR), commonly used in living patients, in the forensic setting. This retrospective study assessed the utility of ANM-PCR in detecting respiratory pathogens in the pediatric forensic setting. Respiratory samples from 35 cases were tested for up to 20 respiratory pathogens.

View Article and Find Full Text PDF

Objectives: With the recent introduction of automated treponemal tests, a new reverse syphilis algorithm has been proposed and now used by many clinical laboratories. We analyzed the impact of instituting the reverse screening syphilis algorithm in a laboratory that serves a geographic area with a moderately high prevalence of syphilis infection.

Methods: Serum samples sent for syphilis testing were tested using a treponemal enzyme immunoassay (EIA) as the screening assay.

View Article and Find Full Text PDF

We compared two rapid, point-of care nucleic acid amplification tests for detection of influenza A and B viruses (Alere i [Alere] and cobas Liat [Roche Diagnostics]) with the influenza A and B virus test components of the FilmArray respiratory panel (BioFire Diagnostics) using 129 respiratory specimens collected in universal viral transport medium (80 influenza A virus and 16 influenza B virus positive) from both adult and pediatric patients. The sensitivities of the Alere test were 71.3% for influenza A virus and 93.

View Article and Find Full Text PDF

Studies have demonstrated that the combination of antimicrobial stewardship programs (ASP) and rapid organism identification improves outcomes in bloodstream infections (BSI) but have not controlled for the incremental contribution of the individual components. Hospitalized adult patients with blood culture pathogens on a rapid, multiplex PCR-based blood culture identification panel (BCID) that included 19 bacterial species, 5 Candida spp., and 4 antimicrobial resistance genes were studied over sequential time periods in a pre-post quasiexperimental study in 3 groups in the following categories: conventional organism identification (controls), conventional organism identification with ASP (AS), and BCID with ASP (BCID).

View Article and Find Full Text PDF

Background.  To improve clinical and public health outcomes through early human immunodeficiency virus (HIV) detection, fourth-generation antigen/antibody immunoassay (4IA) and supplemental testing results must be returned rapidly. Methods.

View Article and Find Full Text PDF