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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Proposed amendments regarding the definitions of multidrug-resistant and extensively drug-resistant bacteria
Petros I Rafailidis1, Diamantis Kofteridis2
12ndDepartment of Internal Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
Introduction:
It is fortunate that an international panel of experts proposed definitions for multidrug-resistant (MDR) and extensively drug-resistant (XDR) in the past.
Areas Covered:
In our opinion, these definitions need amendments in order to be semantically more accurate.
Expert Opinion:
We suggest for the MDR definition to add to 'MDR is defined as non-susceptibility to at least one agent in three or more antimicrobial categories' that this non-susceptibility is at most to the total number of all antimicrobial categories minus two, so that the definition reads: MDR is defined as non-susceptibility to at least one agent in three or more antimicrobial categories and up to (and including) the total number of all antimicrobial categories minus two. We suggest that the experts' definition of XDR as 'non-susceptibility to at least one agent in all but two or fewer antimicrobial categories (i.e. bacterial isolates remain susceptible to only one or two categories)' has to be modified regarding the content of the parenthesis to: (i.e. bacterial isolates remain susceptible to only one or two or even none antimicrobial category [in this latter setting bacterial isolates are resistant to at least one antimicrobial agent in all antimicrobial categories and concurrently there is at least one antimicrobial agent to which the isolate is susceptible to]).
Insights
Definitions for multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria require refinement for semantic accuracy. Proposed amendments enhance clarity for classifying antimicrobial resistance patterns in clinical and research settings.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- International experts previously established definitions for multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria.
- These definitions are crucial for standardizing the classification of antimicrobial resistance globally.
Purpose of the Study:
- To propose amendments to the existing definitions of MDR and XDR for improved semantic accuracy.
- To enhance the precision of classifying bacterial isolates based on their resistance profiles.
Main Methods:
- The study involves a critical review and rephrasing of the established MDR and XDR definitions.
- Proposed modifications focus on clarifying the scope of non-susceptibility within antimicrobial categories.
Main Results:
- The suggested amendment for MDR includes non-susceptibility to agents across a defined range of antimicrobial categories (at least three, up to total categories minus two).
- The proposed revision for XDR clarifies that susceptibility may be retained for one, two, or even zero antimicrobial categories.
Conclusions:
- The refined definitions offer greater semantic accuracy for classifying MDR and XDR bacterial isolates.
- These enhanced definitions will aid in more precise communication and data interpretation in antimicrobial resistance research.
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