FAST: Rapid determinations of antibiotic susceptibility phenotypes using label-free cytometry

• Type of Material: Article
• Authors: Tzu-Hsueh Huang, Georgia Institute of Technology; Yih-Ling Tzeng, Emory University; Robert M. Dickson, Georgia Institute of Technology
• Language: English
• Date: 2018-06-01
• Publisher: Wiley: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2018 International Society for Advancement of Cytometry.
• Final Published Version (URL): http://dx.doi.org/10.1002/cyto.a.23370
• Title of Journal or Parent Work: Cytometry Part A
• ISSN: 1552-4922
• Volume: 93A
• Issue: 6
• Start Page: 639
• End Page: 648
• Grant/Funding Information: The authors gratefully acknowledge support of these studies from the National Institutes of Health, Award number R01AI107116 and the Vasser-Woolley Foundation.
• Keywords: FLOW-CYTOMETRY; IDENTIFICATION; Life Sciences & Biomedicine; multidrug-resistant bacteria; ASSAY; Biochemical Research Methods; multidimensional statistics; OUTCOMES; Biochemistry & Molecular Biology; antibiotic susceptibility test; Cell Biology; BACTERIAL; flow cytometry; Science & Technology; ESCHERICHIA-COLI; pre-blood culture; BLOOD-STREAM INFECTIONS; RESISTANCE
• Research Categories: Biology, Cell; Health Sciences, Medicine and Surgery; Chemistry, Biochemistry

Abstract

Sepsis, a life-threatening immune response to blood infections (bacteremia), has a ∼30% mortality rate and is the 10th leading cause of US hospital deaths. The typical bacterial loads in adult septic patients are ≤100 bacterial cells (colony forming units, CFU) per ml blood, while pediatric patients exhibit only ∼1000 CFU/ml. Due to the low numbers, bacteria must be propagated through ∼24-hours blood cultures to generate sufficient CFUs for diagnosis and further analyses. Herein, we demonstrate that, unlike other rapid post-blood culture antibiotic susceptibility tests (ASTs), our phenotypic approach can drastically accelerate ASTs for the most common sepsis-causing gram-negative pathogens by circumventing long blood culture-based amplification. For all blood isolates of multi-drug resistant pathogens investigated (Escherichia coli, Klebsiella pneumoniae, and Acinetobacter nosocomialis), effective antibiotic(s) were readily identified within the equivalent of 8 hours from initial blood draw using <0.5 mL of adult blood per antibiotic. These methods should drastically improve patient outcomes by significantly reducing time to actionable treatment information and reduce the incidence of antibiotic resistance.