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[In vitro activity of various antibiotics against Shigella strains]
A Willke1, G Altay, N Ertuğrul
1Ankara Universitesi, Tip Fakültesi, Klinik Bakteriyoloji ve Infeksiyon Hastaliklari Anabilim Dali.
Abstract:
The in-vitro activity of ampicillin, chloramphenicol, oxytetracycline, trimethoprim-sulfamethaxazole (TMP-SMX), cefoperazone, ceftriaxone, cefotaxime, ceftizoxime, ofloxacin, pefloxacin, ciprofloxacin and fleroxacin against clinically isolated strains of Shigella spp. (n 42) have been determined in this study. The minimum inhibitory concentrations (MICs) were established using the microtube dilution technique. In shigella strains relatively high percentage of resistance was found against ampicillin (% 36.5), chloramphenicol (% 34), oxytetracycline (% 35), and TMP-SMX (% 25.6). The antibiotic therapy proposals reviewed according to these results.
Insights
This study assessed antibiotic resistance in Shigella strains, finding significant resistance to ampicillin, chloramphenicol, oxytetracycline, and trimethoprim-sulfamethoxazole (TMP-SMX). These findings necessitate a review of current antibiotic treatment strategies for Shigella infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Context:
- Shigella spp. are a leading cause of bacterial dysentery worldwide.
- Antimicrobial resistance poses a significant threat to effective treatment of Shigella infections.
- Monitoring antibiotic susceptibility patterns is crucial for guiding clinical practice.
Purpose:
- To determine the in-vitro antimicrobial activity of twelve commonly used antibiotics against clinically isolated Shigella strains.
- To identify the prevalence of antibiotic resistance among Shigella isolates.
- To inform evidence-based antibiotic therapy recommendations for Shigella infections.
Summary:
- The study evaluated twelve antibiotics against 42 Shigella strains using microtube dilution.
- High resistance rates were observed for ampicillin (36.5%), chloramphenicol (34%), oxytetracycline (35%), and trimethoprim-sulfamethoxazole (TMP-SMX) (25.6%).
- Cefoperazone, ceftriaxone, cefotaxime, ceftizoxime, ofloxacin, pefloxacin, ciprofloxacin, and fleroxacin showed varying degrees of activity, with some isolates remaining susceptible.
Impact:
- The findings highlight the diminishing efficacy of older antibiotics like ampicillin and chloramphenicol against Shigella.
- Results provide critical data for updating treatment guidelines and combating antimicrobial resistance in Shigella infections.
- This research supports the judicious selection of antibiotics for treating shigellosis, potentially reducing treatment failures and spread of resistant strains.
