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Updated: Jul 17, 2026
04:56
Epithelial Cell Infection Analyses with Shigella
Published on: February 9, 2024
Extended-spectrum beta-lactamase-producing Shigella strains in Israel, 2000-2004
Summary
Seven Shigella isolates resistant to ceftriaxone were identified, all producing extended-spectrum beta-lactamases (ESBLs). Molecular analysis revealed CTX-M-type enzymes as the primary cause of resistance in these Shigella strains.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Shigella is a significant cause of bacterial dysentery worldwide.
- Antimicrobial resistance in Shigella poses a growing public health threat.
- Extended-spectrum beta-lactamases (ESBLs) confer resistance to key antibiotics.
Purpose of the Study:
- To investigate the prevalence and characteristics of ESBL-producing Shigella isolates in Israel.
- To identify the specific types of ESBL enzymes present in resistant strains.
- To understand the molecular basis of ceftriaxone resistance in Shigella.
Main Methods:
- Susceptibility testing of 5,616 Shigella isolates from 2000-2004.
- Confirmation of ESBL production using phenotypic methods (combination disk, Vitek 1, double-disk synergy).
- Molecular characterization of ESBL genes using genetic analysis.
Main Results:
- Seven Shigella isolates (S. boydii 2, S. flexneri 2a, S. flexneri 6, S. sonnei) exhibited ceftriaxone resistance.
- All resistant isolates were confirmed ESBL producers.
- CTX-M-type enzymes (CTX-M-9, CTX-M-3, CTX-M-39, CTX-M-2 groups) were identified.
- bla-(OXA) and bla-(TEM) genes were also detected in some strains.
Conclusions:
- The prevalence of ESBL-producing Shigella was low during the study period.
- CTX-M-type enzymes are responsible for ceftriaxone resistance in these isolates.
- Continued surveillance and research into resistance gene spread are crucial.
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