The in vitro effects of EDTA-tris, EDTA-tris-lysozyme, and antimicrobial agents on equine genital isolants of Pseudomonas aeruginosa.

This research investigates how a combination of substances, namely EDTA and tris buffer, and optional lysozyme, impact the growth and antimicrobial resistance of a type of bacteria, Pseudomonas aeruginosa, which can cause genital infections in horses. The study concludes that the combination of EDTA and tris buffer may be a promising treatment method for these infections.

Study Design and Approach

• The study began by collecting five different strains of Pseudomonas aeruginosa from equine genital infection cases and procuring one standard strain of the same bacteria for research purposes.
• The bacteria were then exposed to varying levels of ethylene-diaminetetraacetic acid (EDTA) and tris (hydroxymethyl) aminomethane (also known as tris buffer with pH 8), and EDTA-tris mixed with lysozyme.
• Researchers measured colony forming units of the bacteria and the minimal inhibitory concentrations for 11 antimicrobial agents before and after exposure to the EDTA solutions.

Findings and Observations

• All six strains of bacteria displayed decreased cellular viability after exposure to the EDTA and tris solutions, indicating that this mixture has the potential to kill or inhibit the growth of Pseudomonas aeruginosa.
• The influence on antimicrobial resistance amongst the bacteria was inconsistent and could not be predicted, revealing that while the EDTA-tris mixture could potentially hamper the bacterial response to certain drugs, this outcome is not guaranteed.
• The additional inclusion of lysozyme did not noticeably enhance the effects of the EDTA-tris mixture, suggesting its addition may not be necessary for therapeutic applications.

Implications and Conclusion

• The results of this study suggest that the use of a combination of EDTA and tris buffer could assist in the treatment of equine genital infections caused by Pseudomonas aeruginosa.
• Further research would be needed to clarify the variable outcomes in antimicrobial resistance and to determine the optimal doses and treatment methods for using the EDTA-tris solution in a real-world, clinical context.