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Case-by-case study using antibiotic-EDTA combination to control pseudomonas aeruginosa
Mohamed Z Hussein1, Amro A Amara
1Department of Microbiology and Immunology, Faculty of Medicine, Tanta University, Tanta, Egypt.
Abstract:
Ps. aeruginosa a well-known opportunistic bacterium infects various tissues and organs causing sever problems. In tropical and semitropical countries and because of environmental and sanitizations reasons Ps. aeruginosa acquiring more virulent factors, gained multi-resistant genes, adapt resistant mechanisms for antibiotics, drugs, disinfectants and in general for any toxic compound. Six multidrugs resistant strains out of 260 different bacteria isolated from patients at Tanta University hospital, Tanta, Egypt, used in this study. To evaluate the role of divalent cations in antibiotic resistance we used a medium containing Ca(2+) and Mg(2+). Various antibiotics tested with or without the LC(10) and LC(50) equivalent amount of EDTA against each strain. We found that after adding EDTA, 70% of the strains turned from resistant to sensitive, especially considering those antibiotics, which inhibit protein synthesis, such, as tetracycline. Simple experiment for testing the effect of Antibiotic-EDTA combination on Rabbits skin artificial ulcer(s) infected by Ps. aeruginosa significantly improve the efficiency of using such combination in superficial treatment. We propose using media other than Muller-Hinton agar in antibiotic sensitivity test to select the best antibiotics could be used in vivo or in superficial treatment. A combination between a proper amount of EDTA and antibiotics especially protein inhibitors will improve the control of Ps. aeruginosa.
Insights
Adding EDTA to antibiotic sensitivity tests can reverse multidrug resistance in Pseudomonas aeruginosa (Ps. aeruginosa). This combination therapy shows promise for treating superficial infections, improving antibiotic efficacy.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Pseudomonas aeruginosa (Ps. aeruginosa) is an opportunistic pathogen causing severe infections.
- Multidrug resistance in Ps. aeruginosa is a growing concern, particularly in tropical regions, due to environmental and sanitation factors.
- Ps. aeruginosa exhibits resistance to various antibiotics, drugs, and disinfectants.
Purpose of the Study:
- To investigate the role of divalent cations in antibiotic resistance of Ps. aeruginosa.
- To evaluate the effectiveness of combining antibiotics with EDTA (ethylenediaminetetraacetic acid) against multidrug-resistant Ps. aeruginosa strains.
- To assess the in vivo efficacy of antibiotic-EDTA combinations for superficial wound treatment.
Main Methods:
- Six multidrug-resistant Ps. aeruginosa strains were isolated from patients at Tanta University hospital.
- Antibiotic susceptibility testing was performed using media supplemented with divalent cations (Ca2+ and Mg2+) and varying concentrations of EDTA.
- An in vivo experiment tested the efficacy of antibiotic-EDTA combinations on experimentally infected rabbit skin ulcers.
Main Results:
- Supplementing the culture medium with EDTA reversed antibiotic resistance in 70% of the tested Ps. aeruginosa strains.
- The most significant reversal of resistance was observed with antibiotics targeting protein synthesis, such as tetracycline.
- The antibiotic-EDTA combination demonstrated improved efficacy in treating superficial Ps. aeruginosa-infected rabbit skin ulcers.
Conclusions:
- Divalent cations play a crucial role in the antibiotic resistance mechanisms of Ps. aeruginosa.
- EDTA, particularly in combination with protein synthesis inhibitors, can enhance antibiotic effectiveness against multidrug-resistant Ps. aeruginosa.
- Alternative culture media for antibiotic sensitivity testing may be necessary to accurately predict in vivo treatment outcomes for Ps. aeruginosa infections.
