The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions

Background. Direct disk diffusion susceptibility testing provides faster results than standard microtitre susceptibility. The direct result may impact patient outcome in sepsis if it is accurate and if physicians use the information to promptly and appropriately change antibiotic treatment. Objecti...

Full description

Saved in:
Bibliographic Details
Main Authors: Peter Daley, Adam Comerford, Jurgienne Umali, Carla Penney
Format: Article
Language:English
Published: Wiley 2016-01-01
Series:Canadian Journal of Infectious Diseases and Medical Microbiology
Online Access:http://dx.doi.org/10.1155/2016/5493675
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832550837755314176
author Peter Daley
Adam Comerford
Jurgienne Umali
Carla Penney
author_facet Peter Daley
Adam Comerford
Jurgienne Umali
Carla Penney
author_sort Peter Daley
collection DOAJ
description Background. Direct disk diffusion susceptibility testing provides faster results than standard microtitre susceptibility. The direct result may impact patient outcome in sepsis if it is accurate and if physicians use the information to promptly and appropriately change antibiotic treatment. Objective. To compare the performance of direct disk diffusion with standard susceptibility and to consider physician decisions in response to these early results, for community acquired bacteremia with Gram-negative Bacilli. Methods. Retrospective observational study of all positive blood cultures with Gram-negative Bacilli, collected over one year. Physician antibiotic treatment decisions were assessed by an infectious diseases physician based on information available to the physician at the time of the decision. Results. 89 bottles growing Gram-negative Bacilli were included in the analysis. Direct disk diffusion agreement with standard susceptibility varied widely. In 47 cases (52.8%), the physician should have changed to a narrower spectrum but did not, in 18 cases (20.2%), the physician correctly narrowed from appropriate broad coverage, and in 8 cases (9.0%), the empiric therapy was correct. Discussion. Because inoculum is not standardized, direct susceptibility results do not agree with standard susceptibility results for all drugs. Physicians do not act on direct susceptibility results. Conclusion. Direct susceptibility should be discontinued in clinical microbiology laboratories.
format Article
id doaj-art-6d677d089d234c259b1b12d35271e56d
institution Kabale University
issn 1712-9532
1918-1493
language English
publishDate 2016-01-01
publisher Wiley
record_format Article
series Canadian Journal of Infectious Diseases and Medical Microbiology
spelling doaj-art-6d677d089d234c259b1b12d35271e56d2025-02-03T06:05:46ZengWileyCanadian Journal of Infectious Diseases and Medical Microbiology1712-95321918-14932016-01-01201610.1155/2016/54936755493675The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment DecisionsPeter Daley0Adam Comerford1Jurgienne Umali2Carla Penney3Faculty of Medicine, Memorial University of Newfoundland and Labrador, Room 1J421, 300 Prince Philip Drive, St. John’s, NL, A1B 3V6, CanadaFaculty of Medicine, Memorial University of Newfoundland and Labrador, St. John’s, NL, A1B 3V6, CanadaFaculty of Medicine, Memorial University of Newfoundland and Labrador, St. John’s, NL, A1B 3V6, CanadaFaculty of Medicine, Memorial University of Newfoundland and Labrador, St. John’s, NL, A1B 3V6, CanadaBackground. Direct disk diffusion susceptibility testing provides faster results than standard microtitre susceptibility. The direct result may impact patient outcome in sepsis if it is accurate and if physicians use the information to promptly and appropriately change antibiotic treatment. Objective. To compare the performance of direct disk diffusion with standard susceptibility and to consider physician decisions in response to these early results, for community acquired bacteremia with Gram-negative Bacilli. Methods. Retrospective observational study of all positive blood cultures with Gram-negative Bacilli, collected over one year. Physician antibiotic treatment decisions were assessed by an infectious diseases physician based on information available to the physician at the time of the decision. Results. 89 bottles growing Gram-negative Bacilli were included in the analysis. Direct disk diffusion agreement with standard susceptibility varied widely. In 47 cases (52.8%), the physician should have changed to a narrower spectrum but did not, in 18 cases (20.2%), the physician correctly narrowed from appropriate broad coverage, and in 8 cases (9.0%), the empiric therapy was correct. Discussion. Because inoculum is not standardized, direct susceptibility results do not agree with standard susceptibility results for all drugs. Physicians do not act on direct susceptibility results. Conclusion. Direct susceptibility should be discontinued in clinical microbiology laboratories.http://dx.doi.org/10.1155/2016/5493675
spellingShingle Peter Daley
Adam Comerford
Jurgienne Umali
Carla Penney
The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
Canadian Journal of Infectious Diseases and Medical Microbiology
title The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
title_full The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
title_fullStr The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
title_full_unstemmed The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
title_short The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions
title_sort performance of direct disk diffusion for community acquired bacteremia due to gram negative bacilli and its impact on physician treatment decisions
url http://dx.doi.org/10.1155/2016/5493675
work_keys_str_mv AT peterdaley theperformanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT adamcomerford theperformanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT jurgienneumali theperformanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT carlapenney theperformanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT peterdaley performanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT adamcomerford performanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT jurgienneumali performanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions
AT carlapenney performanceofdirectdiskdiffusionforcommunityacquiredbacteremiaduetogramnegativebacillianditsimpactonphysiciantreatmentdecisions