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Antibiotic Efficacy Testing in an Ex vivo Model of Pseudomonas aeruginosa and Staphylococcus aureus Biofilms in the Cystic Fibrosis Lung
Published on: January 22, 2021
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.
Pakistan Journal of Pharmaceutical Sciences
|August 29, 2006
Summary
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.
