scholarly journals Antibiotic Susceptibility Testing of the Gram-Negative Bacteria Based on Flow Cytometry

2016 ◽  
Vol 7 ◽  
Author(s):  
Claude Saint-Ruf ◽  
Steve Crussard ◽  
Christine Franceschi ◽  
Sylvain Orenga ◽  
Jasmine Ouattara ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Antibiotic Susceptibility ◽  
Susceptibility Testing ◽  
Gram Negative Bacteria ◽  
Antibiotic Susceptibility Testing ◽  
Gram Negative

scholarly journals Rapid diagnosis and reduced workload for urinary tract infection using flowcytometry combined with direct antibiotic susceptibility testing

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254064
Author(s):  
Hanne Margrethe Gilboe ◽  
Olaug Marie Reiakvam ◽  
Linda Aasen ◽  
Trygve Tjade ◽  
Johan Bjerner ◽  
...  
Keyword(s):  
Urinary Tract ◽  
Response Time ◽  
Antibiotic Susceptibility ◽  
Susceptibility Testing ◽  
Urine Samples ◽  
Gram Negative Bacteria ◽  
Antibiotic Susceptibility Testing ◽  
Gram Positive ◽  
Gram Negative ◽  
Tract Infections

Background We evaluated if flowcytometry, using Sysmex UF-5000, could improve diagnosis of urinary tract infections by rapid identification of culture negative and contaminated samples prior to culture plating, thus reducing culture plating workload and response time. We also evaluated if it is possible to reduce the response time for antibiotic susceptibility profiles using the bacteria information flag on Sysmex UF-5000 to differentiate between Gram positive and negative bacteria, followed by direct Antibiotic Susceptibility Testing (dAST) on the positive urine samples. Methods One thousand urine samples were analyzed for bacteria, white blood cells and squamous cells by flowcytometry before culture plating. Results from flowcytometric analysis at different cut-off values were compared to results of culture plating. We evaluated dAST on 100 urine samples that were analyzed as positive by flowcytometry, containing either Gram positive or Gram negative bacteria. Results Using a cut-off value with bacterial count ≥100.000/mL and WBCs ≥10/μL, flowcytometry predicted 42,1% of samples with non-significant growth. We found that most contaminated samples contain few squamous cells. For 52/56 positive samples containing Gram negative bacteria dAST was identical to routine testing. Overall, there was concordance in 555/560 tested antibiotic combinations. Conclusion Flowcytometry offers advantages for diagnosis of urinary tract infections. Screening for negative urine samples on the day of arrival reduces culture plating and workload, and results in shorter response time for the negative samples. The bacteria information flag predicts positive samples containing Gram negative bacteria for dAST with high accuracy, thus Antibiotic Susceptibility Profile can be reported the day after arrival. For the positive samples containing Gram negative bacteria the concordance was very good between dAST and Antibiotic Susceptibility Testing in routine. For positive samples containing Gram positive bacteria the results were not convincing. We did not find any correlation between epithelial cells and contamination.

Querying Automated Antibiotic Susceptibility Testing Instruments: A Novel Population-Based Active Surveillance Method for Multidrug-Resistant Gram-Negative Bacilli

2014 ◽  
Vol 35 (4) ◽  
pp. 336-341 ◽  
Author(s):  
Jessica Reno ◽  
Calista Schenck ◽  
Janine Scott ◽  
Leigh Ann Clark ◽  
Yun F. (Wayne) Wang ◽  
...  
Keyword(s):  
Active Surveillance ◽  
Antibiotic Susceptibility ◽  
Susceptibility Testing ◽  
Multidrug Resistant ◽  
Population Based ◽  
Antibiotic Susceptibility Testing ◽  
Emerging Infections ◽  
Gram Negative ◽  
Ongoing Surveillance ◽  
Testing Instruments

Objective.To describe the implementation of a population-based surveillance system for multidrug-resistant gram-negative bacilli (MDR-GNB).Design.Population-based active surveillance by the Georgia Emerging Infections Program.Setting.Metropolitan Atlanta, starting November 2010.Patients.Residents with MDR-GNB isolated from urine or a normally sterile site culture.Methods.Surveillance was implemented in 3 phases: (1) surveying laboratory antibiotic susceptibility testing practices, (2) piloting surveillance to estimate the proportion of GNB that were MDR, and (3) maintaining ongoing active surveillance for carbapenem-nonsusceptible Enterobacteriaceae and Acinetobacter baumannii using the 2010 Clinical and Laboratory Standards Institute (CLSI) breakpoints. Pilot surveillance required developing and installing queries for GNB on the 3 types of automated testing instruments (ATIs), such as MicroScan, in Atlanta's clinical laboratories. Ongoing surveillance included establishing a process to extract data from ATIs consistently, review charts, manage data, and provide feedback to laboratories.Results.Output from laboratory information systems typically used for surveillance would not reliably capture the CLSI breakpoints, but queries developed for the 3 ATIs did. In November 2010, 0.9% of Enterobacteriaceae isolates and 35.7% of A. baumannii isolates from 21 laboratories were carbapenem nonsusceptible. Over a 5-month period, 82 Enterobacteriaceae and 59 A. baumannii were identified as carbapenem nonsusceptible.Conclusions.Directly querying ATIs, a novel method of active surveillance for MDR-GNB, proved to be a reliable, sustainable, and accurate method that required moderate initial investment and modest maintenance. Ongoing surveillance is critical to assess the burden of and changes in MDR-GNB to inform prevention efforts.

Sign in / Sign up

Export Citation Format

Share Document